sys/netgraph/pppoe/ng_pppoe.c

   1
   2 /*
   3  * ng_pppoe.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_pppoe.c,v 1.23.2.17 2002/07/02 22:17:18 archie Exp $
  40  * $DragonFly: src/sys/netgraph/pppoe/ng_pppoe.c,v 1.8 2005/06/02 22:11:46 swildner Exp $
  41  * $Whistle: ng_pppoe.c,v 1.10 1999/11/01 09:24:52 julian Exp $
  42  */
  43 #if 0
  44 #define AAA printf("pppoe: %s\n", __func__ );
  45 #define BBB printf("-%d-", __LINE__ );
  46 #else
  47 #define AAA
  48 #define BBB
  49 #endif
  50
  51 #include <sys/param.h>
  52 #include <sys/systm.h>
  53 #include <sys/kernel.h>
  54 #include <sys/mbuf.h>
  55 #include <sys/malloc.h>
  56 #include <sys/errno.h>
  57 #include <sys/sysctl.h>
  58 #include <sys/syslog.h>
  59 #include <sys/thread2.h>
  60 #include <net/ethernet.h>
  61
  62 #include <netgraph/ng_message.h>
  63 #include <netgraph/netgraph.h>
  64 #include "ng_pppoe.h"
  65
  66 #define SIGNOFF "session closed"
  67
  68 /*
  69  * This section contains the netgraph method declarations for the
  70  * pppoe node. These methods define the netgraph pppoe 'type'.
  71  */
  72
  73 static ng_constructor_t ng_pppoe_constructor;
  74 static ng_rcvmsg_t      ng_pppoe_rcvmsg;
  75 static ng_shutdown_t    ng_pppoe_rmnode;
  76 static ng_newhook_t     ng_pppoe_newhook;
  77 static ng_connect_t     ng_pppoe_connect;
  78 static ng_rcvdata_t     ng_pppoe_rcvdata;
  79 static ng_disconnect_t  ng_pppoe_disconnect;
  80
  81 /* Netgraph node type descriptor */
  82 static struct ng_type typestruct = {
  83         NG_VERSION,
  84         NG_PPPOE_NODE_TYPE,
  85         NULL,
  86         ng_pppoe_constructor,
  87         ng_pppoe_rcvmsg,
  88         ng_pppoe_rmnode,
  89         ng_pppoe_newhook,
  90         NULL,
  91         ng_pppoe_connect,
  92         ng_pppoe_rcvdata,
  93         ng_pppoe_rcvdata,
  94         ng_pppoe_disconnect,
  95         NULL
  96 };
  97 NETGRAPH_INIT(pppoe, &typestruct);
  98
  99 /*
 100  * States for the session state machine.
 101  * These have no meaning if there is no hook attached yet.
 102  */
 103 enum state {
 104     PPPOE_SNONE=0,      /* [both] Initial state */
 105     PPPOE_LISTENING,    /* [Daemon] Listening for discover initiation pkt */
 106     PPPOE_SINIT,        /* [Client] Sent discovery initiation */
 107     PPPOE_PRIMED,       /* [Server] Awaiting PADI from daemon */
 108     PPPOE_SOFFER,       /* [Server] Sent offer message  (got PADI)*/
 109     PPPOE_SREQ,         /* [Client] Sent a Request */
 110     PPPOE_NEWCONNECTED, /* [Server] Connection established, No data received */
 111     PPPOE_CONNECTED,    /* [Both] Connection established, Data received */
 112     PPPOE_DEAD          /* [Both] */
 113 };
 114
 115 #define NUMTAGS 20 /* number of tags we are set up to work with */
 116
 117 /*
 118  * Information we store for each hook on each node for negotiating the
 119  * session. The mbuf and cluster are freed once negotiation has completed.
 120  * The whole negotiation block is then discarded.
 121  */
 122
 123 struct sess_neg {
 124         struct mbuf             *m; /* holds cluster with last sent packet */
 125         union   packet          *pkt; /* points within the above cluster */
 126         struct callout          timeout_ch;
 127         u_int                   timeout; /* 0,1,2,4,8,16 etc. seconds */
 128         u_int                   numtags;
 129         const struct pppoe_tag  *tags[NUMTAGS];
 130         u_int                   service_len;
 131         u_int                   ac_name_len;
 132
 133         struct datatag          service;
 134         struct datatag          ac_name;
 135 };
 136 typedef struct sess_neg *negp;
 137
 138 /*
 139  * Session information that is needed after connection.
 140  */
 141 struct sess_con {
 142         hook_p                  hook;
 143         u_int16_t               Session_ID;
 144         enum state              state;
 145         char                    creator[NG_NODELEN + 1]; /* who to notify */
 146         struct pppoe_full_hdr   pkt_hdr;        /* used when connected */
 147         negp                    neg;            /* used when negotiating */
 148         /*struct sess_con       *hash_next;*/   /* not yet used */
 149 };
 150 typedef struct sess_con *sessp;
 151
 152 /*
 153  * Information we store for each node
 154  */
 155 struct PPPOE {
 156         node_p          node;           /* back pointer to node */
 157         hook_p          ethernet_hook;
 158         hook_p          debug_hook;
 159         u_int           packets_in;     /* packets in from ethernet */
 160         u_int           packets_out;    /* packets out towards ethernet */
 161         u_int32_t       flags;
 162         /*struct sess_con *buckets[HASH_SIZE];*/        /* not yet used */
 163 };
 164 typedef struct PPPOE *priv_p;
 165
 166 struct ether_header eh_prototype =
 167         {{0xff,0xff,0xff,0xff,0xff,0xff},
 168          {0x00,0x00,0x00,0x00,0x00,0x00},
 169          ETHERTYPE_PPPOE_DISC};
 170
 171 #define PPPOE_KEEPSTANDARD      -1      /* never switch to nonstandard mode */
 172 #define PPPOE_STANDARD          0       /* try standard mode (dangerous!) */
 173 #define PPPOE_NONSTANDARD       1       /* just be in nonstandard mode */
 174 static int pppoe_mode = PPPOE_KEEPSTANDARD;
 175
 176 static int
 177 ngpppoe_set_ethertype(SYSCTL_HANDLER_ARGS)
 178 {
 179         int error;
 180         int val;
 181
 182         val = pppoe_mode;
 183         error = sysctl_handle_int(oidp, &val, sizeof(int), req);
 184         if (error != 0 || req->newptr == NULL)
 185                 return (error);
 186         switch (val) {
 187         case PPPOE_NONSTANDARD:
 188                 pppoe_mode = PPPOE_NONSTANDARD;
 189                 eh_prototype.ether_type = ETHERTYPE_PPPOE_STUPID_DISC;
 190                 break;
 191         case PPPOE_STANDARD:
 192                 pppoe_mode = PPPOE_STANDARD;
 193                 eh_prototype.ether_type = ETHERTYPE_PPPOE_DISC;
 194                 break;
 195         case PPPOE_KEEPSTANDARD:
 196                 pppoe_mode = PPPOE_KEEPSTANDARD;
 197                 eh_prototype.ether_type = ETHERTYPE_PPPOE_DISC;
 198                 break;
 199         default:
 200                 return (EINVAL);
 201         }
 202         return (0);
 203 }
 204
 205 SYSCTL_PROC(_net_graph, OID_AUTO, nonstandard_pppoe, CTLTYPE_INT | CTLFLAG_RW,
 206     0, sizeof(int), ngpppoe_set_ethertype, "I", "nonstandard ethertype");
 207
 208 union uniq {
 209         char bytes[sizeof(void *)];
 210         void * pointer;
 211         };
 212
 213 #define LEAVE(x) do { error = x; goto quit; } while(0)
 214 static void     pppoe_start(sessp sp);
 215 static void     sendpacket(sessp sp);
 216 static void     pppoe_ticker(void *arg);
 217 static const    struct pppoe_tag *scan_tags(sessp sp,
 218                         const struct pppoe_hdr* ph);
 219 static  int     pppoe_send_event(sessp sp, enum cmd cmdid);
 220
 221 /*************************************************************************
 222  * Some basic utilities  from the Linux version with author's permission.*
 223  * Author:      Michal Ostrowski <mostrows@styx.uwaterloo.ca>            *
 224  ************************************************************************/
 225
 226 /*
 227  * Generate a new session id
 228  * XXX find out the FreeBSD locking scheme.
 229  */
 230 static u_int16_t
 231 get_new_sid(node_p node)
 232 {
 233         static int pppoe_sid = 10;
 234         sessp sp;
 235         hook_p  hook;
 236         u_int16_t val;
 237         priv_p privp = node->private;
 238
 239 AAA
 240 restart:
 241         val = pppoe_sid++;
 242         /*
 243          * Spec says 0xFFFF is reserved.
 244          * Also don't use 0x0000
 245          */
 246         if (val == 0xffff) {
 247                 pppoe_sid = 20;
 248                 goto restart;
 249         }
 250
 251         /* Check it isn't already in use */
 252         LIST_FOREACH(hook, &node->hooks, hooks) {
 253                 /* don't check special hooks */
 254                 if ((hook->private == &privp->debug_hook)
 255                 ||  (hook->private == &privp->ethernet_hook))
 256                         continue;
 257                 sp = hook->private;
 258                 if (sp->Session_ID == val)
 259                         goto restart;
 260         }
 261
 262         return val;
 263 }
 264
 265
 266 /*
 267  * Return the location where the next tag can be put
 268  */
 269 static __inline const struct pppoe_tag*
 270 next_tag(const struct pppoe_hdr* ph)
 271 {
 272         return (const struct pppoe_tag*)(((const char*)&ph->tag[0])
 273             + ntohs(ph->length));
 274 }
 275
 276 /*
 277  * Look for a tag of a specific type
 278  * Don't trust any length the other end says.
 279  * but assume we already sanity checked ph->length.
 280  */
 281 static const struct pppoe_tag*
 282 get_tag(const struct pppoe_hdr* ph, u_int16_t idx)
 283 {
 284         const char *const end = (const char *)next_tag(ph);
 285         const char *ptn;
 286         const struct pppoe_tag *pt = &ph->tag[0];
 287         /*
 288          * Keep processing tags while a tag header will still fit.
 289          */
 290 AAA
 291         while((const char*)(pt + 1) <= end) {
 292             /*
 293              * If the tag data would go past the end of the packet, abort.
 294              */
 295             ptn = (((const char *)(pt + 1)) + ntohs(pt->tag_len));
 296             if(ptn > end)
 297                 return NULL;
 298
 299             if(pt->tag_type == idx)
 300                 return pt;
 301
 302             pt = (const struct pppoe_tag*)ptn;
 303         }
 304         return NULL;
 305 }
 306
 307 /**************************************************************************
 308  * inlines to initialise or add tags to a session's tag list,
 309  **************************************************************************/
 310 /*
 311  * Initialise the session's tag list
 312  */
 313 static void
 314 init_tags(sessp sp)
 315 {
 316 AAA
 317         if(sp->neg == NULL) {
 318                 printf("pppoe: asked to init NULL neg pointer\n");
 319                 return;
 320         }
 321         sp->neg->numtags = 0;
 322 }
 323
 324 static void
 325 insert_tag(sessp sp, const struct pppoe_tag *tp)
 326 {
 327         int     i;
 328         negp neg;
 329
 330 AAA
 331         if((neg = sp->neg) == NULL) {
 332                 printf("pppoe: asked to use NULL neg pointer\n");
 333                 return;
 334         }
 335         if ((i = neg->numtags++) < NUMTAGS) {
 336                 neg->tags[i] = tp;
 337         } else {
 338                 printf("pppoe: asked to add too many tags to packet\n");
 339                 neg->numtags--;
 340         }
 341 }
 342
 343 /*
 344  * Make up a packet, using the tags filled out for the session.
 345  *
 346  * Assume that the actual pppoe header and ethernet header
 347  * are filled out externally to this routine.
 348  * Also assume that neg->wh points to the correct
 349  * location at the front of the buffer space.
 350  */
 351 static void
 352 make_packet(sessp sp) {
 353         struct pppoe_full_hdr *wh = &sp->neg->pkt->pkt_header;
 354         const struct pppoe_tag **tag;
 355         char *dp;
 356         int count;
 357         int tlen;
 358         u_int16_t length = 0;
 359
 360 AAA
 361         if ((sp->neg == NULL) || (sp->neg->m == NULL)) {
 362                 printf("pppoe: make_packet called from wrong state\n");
 363         }
 364         dp = (char *)wh->ph.tag;
 365         for (count = 0, tag = sp->neg->tags;
 366             ((count < sp->neg->numtags) && (count < NUMTAGS));
 367             tag++, count++) {
 368                 tlen = ntohs((*tag)->tag_len) + sizeof(**tag);
 369                 if ((length + tlen) > (ETHER_MAX_LEN - 4 - sizeof(*wh))) {
 370                         printf("pppoe: tags too long\n");
 371                         sp->neg->numtags = count;
 372                         break;  /* XXX chop off what's too long */
 373                 }
 374                 bcopy(*tag, (char *)dp, tlen);
 375                 length += tlen;
 376                 dp += tlen;
 377         }
 378         wh->ph.length = htons(length);
 379         sp->neg->m->m_len = length + sizeof(*wh);
 380         sp->neg->m->m_pkthdr.len = length + sizeof(*wh);
 381 }
 382
 383 /**************************************************************************
 384  * Routine to match a service offered                                     *
 385  **************************************************************************/
 386 /*
 387  * Find a hook that has a service string that matches that
 388  * we are seeking. for now use a simple string.
 389  * In the future we may need something like regexp().
 390  * for testing allow a null string to match 1st found and a null service
 391  * to match all requests. Also make '*' do the same.
 392  */
 393
 394 #define NG_MATCH_EXACT  1
 395 #define NG_MATCH_ANY    2
 396
 397 static hook_p
 398 pppoe_match_svc(node_p node, const char *svc_name, int svc_len, int match)
 399 {
 400         sessp   sp      = NULL;
 401         negp    neg     = NULL;
 402         priv_p  privp   = node->private;
 403         hook_p  allhook = NULL;
 404         hook_p  hook;
 405
 406 AAA
 407         LIST_FOREACH(hook, &node->hooks, hooks) {
 408
 409                 /* skip any hook that is debug or ethernet */
 410                 if ((hook->private == &privp->debug_hook)
 411                 ||  (hook->private == &privp->ethernet_hook))
 412                         continue;
 413                 sp = hook->private;
 414
 415                 /* Skip any sessions which are not in LISTEN mode. */
 416                 if ( sp->state != PPPOE_LISTENING)
 417                         continue;
 418
 419                 neg = sp->neg;
 420
 421                 /* Special case for a blank or "*" service name (wildcard) */
 422                 if (match == NG_MATCH_ANY && neg->service_len == 1 &&
 423                     neg->service.data[0] == '*') {
 424                         allhook = hook;
 425                         continue;
 426                 }
 427
 428                 /* If the lengths don't match, that aint it. */
 429                 if (neg->service_len != svc_len)
 430                         continue;
 431
 432                 /* An exact match? */
 433                 if (svc_len == 0)
 434                         break;
 435
 436                 if (strncmp(svc_name, neg->service.data, svc_len) == 0)
 437                         break;
 438         }
 439         return (hook ? hook : allhook);
 440 }
 441 /**************************************************************************
 442  * Routine to find a particular session that matches an incoming packet   *
 443  **************************************************************************/
 444 static hook_p
 445 pppoe_findsession(node_p node, const struct pppoe_full_hdr *wh)
 446 {
 447         sessp   sp = NULL;
 448         hook_p hook = NULL;
 449         priv_p  privp = node->private;
 450         u_int16_t       session = ntohs(wh->ph.sid);
 451
 452         /*
 453          * find matching peer/session combination.
 454          */
 455 AAA
 456         LIST_FOREACH(hook, &node->hooks, hooks) {
 457                 /* don't check special hooks */
 458                 if ((hook->private == &privp->debug_hook)
 459                 ||  (hook->private == &privp->ethernet_hook)) {
 460                         continue;
 461                 }
 462                 sp = hook->private;
 463                 if ( ( (sp->state == PPPOE_CONNECTED)
 464                     || (sp->state == PPPOE_NEWCONNECTED) )
 465                 && (sp->Session_ID == session)
 466                 && (bcmp(sp->pkt_hdr.eh.ether_dhost,
 467                     wh->eh.ether_shost,
 468                     ETHER_ADDR_LEN)) == 0) {
 469                         break;
 470                 }
 471         }
 472         return (hook);
 473 }
 474
 475 static hook_p
 476 pppoe_finduniq(node_p node, const struct pppoe_tag *tag)
 477 {
 478         hook_p hook = NULL;
 479         priv_p  privp = node->private;
 480         union uniq              uniq;
 481
 482 AAA
 483         bcopy(tag->tag_data, uniq.bytes, sizeof(void *));
 484         /* cycle through all known hooks */
 485         LIST_FOREACH(hook, &node->hooks, hooks) {
 486                 /* don't check special hooks */
 487                 if ((hook->private == &privp->debug_hook)
 488                 ||  (hook->private == &privp->ethernet_hook))
 489                         continue;
 490                 if (uniq.pointer == hook->private)
 491                         break;
 492         }
 493         return (hook);
 494 }
 495
 496 /**************************************************************************
 497  * start of Netgraph entrypoints                                          *
 498  **************************************************************************/
 499
 500 /*
 501  * Allocate the private data structure and the generic node
 502  * and link them together.
 503  *
 504  * ng_make_node_common() returns with a generic node struct
 505  * with a single reference for us.. we transfer it to the
 506  * private structure.. when we free the private struct we must
 507  * unref the node so it gets freed too.
 508  */
 509 static int
 510 ng_pppoe_constructor(node_p *nodep)
 511 {
 512         priv_p privdata;
 513         int error;
 514
 515 AAA
 516         /* Initialize private descriptor */
 517         MALLOC(privdata, priv_p, sizeof(*privdata), M_NETGRAPH, M_NOWAIT);
 518         if (privdata == NULL)
 519                 return (ENOMEM);
 520         bzero(privdata, sizeof(*privdata));
 521
 522         /* Call the 'generic' (ie, superclass) node constructor */
 523         if ((error = ng_make_node_common(&typestruct, nodep))) {
 524                 FREE(privdata, M_NETGRAPH);
 525                 return (error);
 526         }
 527
 528         /* Link structs together; this counts as our one reference to *nodep */
 529         (*nodep)->private = privdata;
 530         privdata->node = *nodep;
 531         return (0);
 532 }
 533
 534 /*
 535  * Give our ok for a hook to be added...
 536  * point the hook's private info to the hook structure.
 537  *
 538  * The following hook names are special:
 539  *  Ethernet:  the hook that should be connected to a NIC.
 540  *  debug:      copies of data sent out here  (when I write the code).
 541  * All other hook names need only be unique. (the framework checks this).
 542  */
 543 static int
 544 ng_pppoe_newhook(node_p node, hook_p hook, const char *name)
 545 {
 546         const priv_p privp = node->private;
 547         sessp sp;
 548
 549 AAA
 550         if (strcmp(name, NG_PPPOE_HOOK_ETHERNET) == 0) {
 551                 privp->ethernet_hook = hook;
 552                 hook->private = &privp->ethernet_hook;
 553         } else if (strcmp(name, NG_PPPOE_HOOK_DEBUG) == 0) {
 554                 privp->debug_hook = hook;
 555                 hook->private = &privp->debug_hook;
 556         } else {
 557                 /*
 558                  * Any other unique name is OK.
 559                  * The infrastructure has already checked that it's unique,
 560                  * so just allocate it and hook it in.
 561                  */
 562                 MALLOC(sp, sessp, sizeof(*sp), M_NETGRAPH, M_NOWAIT);
 563                 if (sp == NULL) {
 564                                 return (ENOMEM);
 565                 }
 566                 bzero(sp, sizeof(*sp));
 567
 568                 hook->private = sp;
 569                 sp->hook = hook;
 570         }
 571         return(0);
 572 }
 573
 574 /*
 575  * Get a netgraph control message.
 576  * Check it is one we understand. If needed, send a response.
 577  * We sometimes save the address for an async action later.
 578  * Always free the message.
 579  */
 580 static int
 581 ng_pppoe_rcvmsg(node_p node,
 582            struct ng_mesg *msg, const char *retaddr, struct ng_mesg **rptr)
 583 {
 584         priv_p privp = node->private;
 585         struct ngpppoe_init_data *ourmsg = NULL;
 586         struct ng_mesg *resp = NULL;
 587         int error = 0;
 588         hook_p hook = NULL;
 589         sessp sp = NULL;
 590         negp neg = NULL;
 591
 592 AAA
 593         /* Deal with message according to cookie and command */
 594         switch (msg->header.typecookie) {
 595         case NGM_PPPOE_COOKIE:
 596                 switch (msg->header.cmd) {
 597                 case NGM_PPPOE_CONNECT:
 598                 case NGM_PPPOE_LISTEN:
 599                 case NGM_PPPOE_OFFER:
 600                 case NGM_PPPOE_SERVICE:
 601                         ourmsg = (struct ngpppoe_init_data *)msg->data;
 602                         if (( sizeof(*ourmsg) > msg->header.arglen)
 603                         || ((sizeof(*ourmsg) + ourmsg->data_len)
 604                             > msg->header.arglen)) {
 605                                 printf("pppoe_rcvmsg: bad arg size");
 606                                 LEAVE(EMSGSIZE);
 607                         }
 608                         if (ourmsg->data_len > PPPOE_SERVICE_NAME_SIZE) {
 609                                 printf("pppoe: init data too long (%d)\n",
 610                                                         ourmsg->data_len);
 611                                 LEAVE(EMSGSIZE);
 612                         }
 613                         /* make sure strcmp will terminate safely */
 614                         ourmsg->hook[sizeof(ourmsg->hook) - 1] = '\0';
 615
 616                         /* cycle through all known hooks */
 617                         LIST_FOREACH(hook, &node->hooks, hooks) {
 618                                 if (hook->name
 619                                 && strcmp(hook->name, ourmsg->hook) == 0)
 620                                         break;
 621                         }
 622                         if (hook == NULL) {
 623                                 LEAVE(ENOENT);
 624                         }
 625                         if ((hook->private == &privp->debug_hook)
 626                         ||  (hook->private == &privp->ethernet_hook)) {
 627                                 LEAVE(EINVAL);
 628                         }
 629                         sp = hook->private;
 630
 631                         if (msg->header.cmd == NGM_PPPOE_LISTEN) {
 632                                 /*
 633                                  * Ensure we aren't already listening for this
 634                                  * service.
 635                                  */
 636                                 if (pppoe_match_svc(node, ourmsg->data,
 637                                     ourmsg->data_len, NG_MATCH_EXACT) != NULL) {
 638                                         LEAVE(EEXIST);
 639                                 }
 640                         }
 641
 642                         /*
 643                          * PPPOE_SERVICE advertisments are set up
 644                          * on sessions that are in PRIMED state.
 645                          */
 646                         if (msg->header.cmd == NGM_PPPOE_SERVICE) {
 647                                 break;
 648                         }
 649                         if (sp->state |= PPPOE_SNONE) {
 650                                 printf("pppoe: Session already active\n");
 651                                 LEAVE(EISCONN);
 652                         }
 653
 654                         /*
 655                          * set up prototype header
 656                          */
 657                         MALLOC(neg, negp, sizeof(*neg), M_NETGRAPH, M_NOWAIT);
 658
 659                         if (neg == NULL) {
 660                                 printf("pppoe: Session out of memory\n");
 661                                 LEAVE(ENOMEM);
 662                         }
 663                         bzero(neg, sizeof(*neg));
 664                         MGETHDR(neg->m, MB_DONTWAIT, MT_DATA);
 665                         if(neg->m == NULL) {
 666                                 printf("pppoe: Session out of mbufs\n");
 667                                 FREE(neg, M_NETGRAPH);
 668                                 LEAVE(ENOBUFS);
 669                         }
 670                         neg->m->m_pkthdr.rcvif = NULL;
 671                         MCLGET(neg->m, MB_DONTWAIT);
 672                         if ((neg->m->m_flags & M_EXT) == 0) {
 673                                 printf("pppoe: Session out of mcls\n");
 674                                 m_freem(neg->m);
 675                                 FREE(neg, M_NETGRAPH);
 676                                 LEAVE(ENOBUFS);
 677                         }
 678                         sp->neg = neg;
 679                         callout_init(&neg->timeout_ch);
 680                         neg->m->m_len = sizeof(struct pppoe_full_hdr);
 681                         neg->pkt = mtod(neg->m, union packet*);
 682                         neg->pkt->pkt_header.eh = eh_prototype;
 683                         neg->pkt->pkt_header.ph.ver = 0x1;
 684                         neg->pkt->pkt_header.ph.type = 0x1;
 685                         neg->pkt->pkt_header.ph.sid = 0x0000;
 686                         neg->timeout = 0;
 687
 688                         strncpy(sp->creator, retaddr, NG_NODELEN);
 689                         sp->creator[NG_NODELEN] = '\0';
 690                 }
 691                 switch (msg->header.cmd) {
 692                 case NGM_PPPOE_GET_STATUS:
 693                     {
 694                         struct ngpppoestat *stats;
 695
 696                         NG_MKRESPONSE(resp, msg, sizeof(*stats), M_NOWAIT);
 697                         if (!resp) {
 698                                 LEAVE(ENOMEM);
 699                         }
 700                         stats = (struct ngpppoestat *) resp->data;
 701                         stats->packets_in = privp->packets_in;
 702                         stats->packets_out = privp->packets_out;
 703                         break;
 704                     }
 705                 case NGM_PPPOE_CONNECT:
 706                         /*
 707                          * Check the hook exists and is Uninitialised.
 708                          * Send a PADI request, and start the timeout logic.
 709                          * Store the originator of this message so we can send
 710                          * a success of fail message to them later.
 711                          * Move the session to SINIT
 712                          * Set up the session to the correct state and
 713                          * start it.
 714                          */
 715                         neg->service.hdr.tag_type = PTT_SRV_NAME;
 716                         neg->service.hdr.tag_len =
 717                                         htons((u_int16_t)ourmsg->data_len);
 718                         if (ourmsg->data_len) {
 719                                 bcopy(ourmsg->data,
 720                                         neg->service.data, ourmsg->data_len);
 721                         }
 722                         neg->service_len = ourmsg->data_len;
 723                         pppoe_start(sp);
 724                         break;
 725                 case NGM_PPPOE_LISTEN:
 726                         /*
 727                          * Check the hook exists and is Uninitialised.
 728                          * Install the service matching string.
 729                          * Store the originator of this message so we can send
 730                          * a success of fail message to them later.
 731                          * Move the hook to 'LISTENING'
 732                          */
 733                         neg->service.hdr.tag_type = PTT_SRV_NAME;
 734                         neg->service.hdr.tag_len =
 735                                         htons((u_int16_t)ourmsg->data_len);
 736
 737                         if (ourmsg->data_len) {
 738                                 bcopy(ourmsg->data,
 739                                         neg->service.data, ourmsg->data_len);
 740                         }
 741                         neg->service_len = ourmsg->data_len;
 742                         neg->pkt->pkt_header.ph.code = PADT_CODE;
 743                         /*
 744                          * wait for PADI packet coming from ethernet
 745                          */
 746                         sp->state = PPPOE_LISTENING;
 747                         break;
 748                 case NGM_PPPOE_OFFER:
 749                         /*
 750                          * Check the hook exists and is Uninitialised.
 751                          * Store the originator of this message so we can send
 752                          * a success of fail message to them later.
 753                          * Store the AC-Name given and go to PRIMED.
 754                          */
 755                         neg->ac_name.hdr.tag_type = PTT_AC_NAME;
 756                         neg->ac_name.hdr.tag_len =
 757                                         htons((u_int16_t)ourmsg->data_len);
 758                         if (ourmsg->data_len) {
 759                                 bcopy(ourmsg->data,
 760                                         neg->ac_name.data, ourmsg->data_len);
 761                         }
 762                         neg->ac_name_len = ourmsg->data_len;
 763                         neg->pkt->pkt_header.ph.code = PADO_CODE;
 764                         /*
 765                          * Wait for PADI packet coming from hook
 766                          */
 767                         sp->state = PPPOE_PRIMED;
 768                         break;
 769                 case NGM_PPPOE_SERVICE:
 770                         /*
 771                          * Check the session is primed.
 772                          * for now just allow ONE service to be advertised.
 773                          * If you do it twice you just overwrite.
 774                          */
 775                         if (sp->state != PPPOE_PRIMED) {
 776                                 printf("pppoe: Session not primed\n");
 777                                 LEAVE(EISCONN);
 778                         }
 779                         neg = sp->neg;
 780                         neg->service.hdr.tag_type = PTT_SRV_NAME;
 781                         neg->service.hdr.tag_len =
 782                             htons((u_int16_t)ourmsg->data_len);
 783
 784                         if (ourmsg->data_len)
 785                                 bcopy(ourmsg->data, neg->service.data,
 786                                     ourmsg->data_len);
 787                         neg->service_len = ourmsg->data_len;
 788                         break;
 789                 default:
 790                         LEAVE(EINVAL);
 791                 }
 792                 break;
 793         default:
 794                 LEAVE(EINVAL);
 795         }
 796
 797         /* Take care of synchronous response, if any */
 798         if (rptr)
 799                 *rptr = resp;
 800         else if (resp)
 801                 FREE(resp, M_NETGRAPH);
 802
 803         /* Free the message and return */
 804 quit:
 805         FREE(msg, M_NETGRAPH);
 806         return(error);
 807 }
 808
 809 /*
 810  * Start a client into the first state. A separate function because
 811  * it can be needed if the negotiation times out.
 812  */
 813 static void
 814 pppoe_start(sessp sp)
 815 {
 816         struct {
 817                 struct pppoe_tag hdr;
 818                 union   uniq    data;
 819         } __attribute ((packed)) uniqtag;
 820
 821         /*
 822          * kick the state machine into starting up
 823          */
 824 AAA
 825         sp->state = PPPOE_SINIT;
 826         /* reset the packet header to broadcast */
 827         sp->neg->pkt->pkt_header.eh = eh_prototype;
 828         sp->neg->pkt->pkt_header.ph.code = PADI_CODE;
 829         uniqtag.hdr.tag_type = PTT_HOST_UNIQ;
 830         uniqtag.hdr.tag_len = htons((u_int16_t)sizeof(uniqtag.data));
 831         uniqtag.data.pointer = sp;
 832         init_tags(sp);
 833         insert_tag(sp, &uniqtag.hdr);
 834         insert_tag(sp, &sp->neg->service.hdr);
 835         make_packet(sp);
 836         sendpacket(sp);
 837 }
 838
 839 static int
 840 send_acname(sessp sp, const struct pppoe_tag *tag)
 841 {
 842         int error, tlen;
 843         struct ng_mesg *msg;
 844         struct ngpppoe_sts *sts;
 845
 846         NG_MKMESSAGE(msg, NGM_PPPOE_COOKIE, NGM_PPPOE_ACNAME,
 847             sizeof(struct ngpppoe_sts), M_NOWAIT);
 848         if (msg == NULL)
 849                 return (ENOMEM);
 850
 851         sts = (struct ngpppoe_sts *)msg->data;
 852         tlen = min(NG_HOOKLEN, ntohs(tag->tag_len));
 853         strncpy(sts->hook, tag->tag_data, tlen);
 854         sts->hook[tlen] = '\0';
 855         error = ng_send_msg(sp->hook->node, msg, sp->creator, NULL);
 856
 857         return (error);
 858 }
 859
 860 static int
 861 send_sessionid(sessp sp)
 862 {
 863         int error;
 864         struct ng_mesg *msg;
 865
 866         NG_MKMESSAGE(msg, NGM_PPPOE_COOKIE, NGM_PPPOE_SESSIONID,
 867             sizeof(u_int16_t), M_NOWAIT);
 868         if (msg == NULL)
 869                 return (ENOMEM);
 870
 871         *(u_int16_t *)msg->data = sp->Session_ID;
 872         error = ng_send_msg(sp->hook->node, msg, sp->creator, NULL);
 873
 874         return (error);
 875 }
 876
 877 /*
 878  * Receive data, and do something with it.
 879  * The caller will never free m or meta, so
 880  * if we use up this data or abort we must free BOTH of these.
 881  */
 882 static int
 883 ng_pppoe_rcvdata(hook_p hook, struct mbuf *m, meta_p meta)
 884 {
 885         node_p                  node = hook->node;
 886         const priv_p            privp = node->private;
 887         sessp                   sp = hook->private;
 888         const struct pppoe_full_hdr *wh;
 889         const struct pppoe_hdr  *ph;
 890         int                     error = 0;
 891         u_int16_t               session;
 892         u_int16_t               length;
 893         u_int8_t                code;
 894         const struct pppoe_tag  *utag = NULL, *tag = NULL;
 895         hook_p                  sendhook;
 896         struct {
 897                 struct pppoe_tag hdr;
 898                 union   uniq    data;
 899         } __attribute ((packed)) uniqtag;
 900         negp                    neg = NULL;
 901
 902 AAA
 903         if (hook->private == &privp->debug_hook) {
 904                 /*
 905                  * Data from the debug hook gets sent without modification
 906                  * straight to the ethernet.
 907                  */
 908                 NG_SEND_DATA( error, privp->ethernet_hook, m, meta);
 909                 privp->packets_out++;
 910         } else if (hook->private == &privp->ethernet_hook) {
 911                 /*
 912                  * Incoming data.
 913                  * Dig out various fields from the packet.
 914                  * use them to decide where to send it.
 915                  */
 916
 917                 privp->packets_in++;
 918                 if( m->m_len < sizeof(*wh)) {
 919                         m = m_pullup(m, sizeof(*wh)); /* Checks length */
 920                         if (m == NULL) {
 921                                 printf("couldn't m_pullup\n");
 922                                 LEAVE(ENOBUFS);
 923                         }
 924                 }
 925                 wh = mtod(m, struct pppoe_full_hdr *);
 926                 ph = &wh->ph;
 927                 session = ntohs(wh->ph.sid);
 928                 length = ntohs(wh->ph.length);
 929                 code = wh->ph.code;
 930                 switch(wh->eh.ether_type) {
 931                 case    ETHERTYPE_PPPOE_STUPID_DISC:
 932                         if (pppoe_mode == PPPOE_STANDARD) {
 933                                 pppoe_mode = PPPOE_NONSTANDARD;
 934                                 eh_prototype.ether_type =
 935                                     ETHERTYPE_PPPOE_STUPID_DISC;
 936                                 log(LOG_NOTICE,
 937                                     "Switched to nonstandard PPPoE mode due to "
 938                                     "packet from %*D\n",
 939                                     ETHER_ADDR_LEN,
 940                                     wh->eh.ether_shost, ":");
 941                         } else if (pppoe_mode == PPPOE_KEEPSTANDARD)
 942                                 log(LOG_NOTICE,
 943                                     "Ignored nonstandard PPPoE packet "
 944                                     "from %*D\n",
 945                                     ETHER_ADDR_LEN,
 946                                     wh->eh.ether_shost, ":");
 947                         /* fall through */
 948                 case    ETHERTYPE_PPPOE_DISC:
 949                         /*
 950                          * We need to try to make sure that the tag area
 951                          * is contiguous, or we could wander off the end
 952                          * of a buffer and make a mess.
 953                          * (Linux wouldn't have this problem).
 954                          */
 955 /*XXX fix this mess */
 956
 957                         if (m->m_pkthdr.len <= MHLEN) {
 958                                 if( m->m_len < m->m_pkthdr.len) {
 959                                         m = m_pullup(m, m->m_pkthdr.len);
 960                                         if (m == NULL) {
 961                                                 printf("couldn't m_pullup\n");
 962                                                 LEAVE(ENOBUFS);
 963                                         }
 964                                 }
 965                         }
 966                         if (m->m_len != m->m_pkthdr.len) {
 967                                 /*
 968                                  * It's not all in one piece.
 969                                  * We need to do extra work.
 970                                  */
 971                                 printf("packet fragmented\n");
 972                                 LEAVE(EMSGSIZE);
 973                         }
 974
 975                         switch(code) {
 976                         case    PADI_CODE:
 977                                 /*
 978                                  * We are a server:
 979                                  * Look for a hook with the required service
 980                                  * and send the ENTIRE packet up there.
 981                                  * It should come back to a new hook in
 982                                  * PRIMED state. Look there for further
 983                                  * processing.
 984                                  */
 985                                 tag = get_tag(ph, PTT_SRV_NAME);
 986                                 if (tag == NULL) {
 987                                         printf("no service tag\n");
 988                                         LEAVE(ENETUNREACH);
 989                                 }
 990                                 sendhook = pppoe_match_svc(hook->node,
 991                                         tag->tag_data, ntohs(tag->tag_len),
 992                                         NG_MATCH_ANY);
 993                                 if (sendhook) {
 994                                         NG_SEND_DATA(error, sendhook, m, meta);
 995                                 } else {
 996                                         LEAVE(ENETUNREACH);
 997                                 }
 998                                 break;
 999                         case    PADO_CODE:
1000                                 /*
1001                                  * We are a client:
1002                                  * Use the host_uniq tag to find the
1003                                  * hook this is in response to.
1004                                  * Received #2, now send #3
1005                                  * For now simply accept the first we receive.
1006                                  */
1007                                 utag = get_tag(ph, PTT_HOST_UNIQ);
1008                                 if ((utag == NULL)
1009                                 || (ntohs(utag->tag_len) != sizeof(sp))) {
1010                                         printf("no host unique field\n");
1011                                         LEAVE(ENETUNREACH);
1012                                 }
1013
1014                                 sendhook = pppoe_finduniq(node, utag);
1015                                 if (sendhook == NULL) {
1016                                         printf("no matching session\n");
1017                                         LEAVE(ENETUNREACH);
1018                                 }
1019
1020                                 /*
1021                                  * Check the session is in the right state.
1022                                  * It needs to be in PPPOE_SINIT.
1023                                  */
1024                                 sp = sendhook->private;
1025                                 if (sp->state != PPPOE_SINIT) {
1026                                         printf("session in wrong state\n");
1027                                         LEAVE(ENETUNREACH);
1028                                 }
1029                                 neg = sp->neg;
1030                                 callout_stop(&neg->timeout_ch);
1031
1032                                 /*
1033                                  * This is the first time we hear
1034                                  * from the server, so note it's
1035                                  * unicast address, replacing the
1036                                  * broadcast address .
1037                                  */
1038                                 bcopy(wh->eh.ether_shost,
1039                                         neg->pkt->pkt_header.eh.ether_dhost,
1040                                         ETHER_ADDR_LEN);
1041                                 neg->timeout = 0;
1042                                 neg->pkt->pkt_header.ph.code = PADR_CODE;
1043                                 init_tags(sp);
1044                                 insert_tag(sp, utag);      /* Host Unique */
1045                                 if ((tag = get_tag(ph, PTT_AC_COOKIE)))
1046                                         insert_tag(sp, tag); /* return cookie */
1047                                 if ((tag = get_tag(ph, PTT_AC_NAME))) {
1048                                         insert_tag(sp, tag); /* return it */
1049                                         send_acname(sp, tag);
1050                                 }
1051                                 insert_tag(sp, &neg->service.hdr); /* Service */
1052                                 scan_tags(sp, ph);
1053                                 make_packet(sp);
1054                                 sp->state = PPPOE_SREQ;
1055                                 sendpacket(sp);
1056                                 break;
1057                         case    PADR_CODE:
1058
1059                                 /*
1060                                  * We are a server:
1061                                  * Use the ac_cookie tag to find the
1062                                  * hook this is in response to.
1063                                  */
1064                                 utag = get_tag(ph, PTT_AC_COOKIE);
1065                                 if ((utag == NULL)
1066                                 || (ntohs(utag->tag_len) != sizeof(sp))) {
1067                                         LEAVE(ENETUNREACH);
1068                                 }
1069
1070                                 sendhook = pppoe_finduniq(node, utag);
1071                                 if (sendhook == NULL) {
1072                                         LEAVE(ENETUNREACH);
1073                                 }
1074
1075                                 /*
1076                                  * Check the session is in the right state.
1077                                  * It needs to be in PPPOE_SOFFER
1078                                  * or PPPOE_NEWCONNECTED. If the latter,
1079                                  * then this is a retry by the client.
1080                                  * so be nice, and resend.
1081                                  */
1082                                 sp = sendhook->private;
1083                                 if (sp->state == PPPOE_NEWCONNECTED) {
1084                                         /*
1085                                          * Whoa! drop back to resend that
1086                                          * PADS packet.
1087                                          * We should still have a copy of it.
1088                                          */
1089                                         sp->state = PPPOE_SOFFER;
1090                                 }
1091                                 if (sp->state != PPPOE_SOFFER) {
1092                                         LEAVE (ENETUNREACH);
1093                                         break;
1094                                 }
1095                                 neg = sp->neg;
1096                                 callout_stop(&neg->timeout_ch);
1097                                 neg->pkt->pkt_header.ph.code = PADS_CODE;
1098                                 if (sp->Session_ID == 0)
1099                                         neg->pkt->pkt_header.ph.sid =
1100                                             htons(sp->Session_ID
1101                                                 = get_new_sid(node));
1102                                 send_sessionid(sp);
1103                                 neg->timeout = 0;
1104                                 /*
1105                                  * start working out the tags to respond with.
1106                                  */
1107                                 init_tags(sp);
1108                                 insert_tag(sp, &neg->ac_name.hdr); /* AC_NAME */
1109                                 if ((tag = get_tag(ph, PTT_SRV_NAME)))
1110                                         insert_tag(sp, tag);/* return service */
1111                                 if ((tag = get_tag(ph, PTT_HOST_UNIQ)))
1112                                         insert_tag(sp, tag); /* return it */
1113                                 insert_tag(sp, utag);   /* ac_cookie */
1114                                 scan_tags(sp, ph);
1115                                 make_packet(sp);
1116                                 sp->state = PPPOE_NEWCONNECTED;
1117                                 sendpacket(sp);
1118                                 /*
1119                                  * Having sent the last Negotiation header,
1120                                  * Set up the stored packet header to
1121                                  * be correct for the actual session.
1122                                  * But keep the negotialtion stuff
1123                                  * around in case we need to resend this last
1124                                  * packet. We'll discard it when we move
1125                                  * from NEWCONNECTED to CONNECTED
1126                                  */
1127                                 sp->pkt_hdr = neg->pkt->pkt_header;
1128                                 if (pppoe_mode == PPPOE_NONSTANDARD)
1129                                         sp->pkt_hdr.eh.ether_type
1130                                                 = ETHERTYPE_PPPOE_STUPID_SESS;
1131                                 else
1132                                         sp->pkt_hdr.eh.ether_type
1133                                                 = ETHERTYPE_PPPOE_SESS;
1134                                 sp->pkt_hdr.ph.code = 0;
1135                                 pppoe_send_event(sp, NGM_PPPOE_SUCCESS);
1136                                 break;
1137                         case    PADS_CODE:
1138                                 /*
1139                                  * We are a client:
1140                                  * Use the host_uniq tag to find the
1141                                  * hook this is in response to.
1142                                  * take the session ID and store it away.
1143                                  * Also make sure the pre-made header is
1144                                  * correct and set us into Session mode.
1145                                  */
1146                                 utag = get_tag(ph, PTT_HOST_UNIQ);
1147                                 if ((utag == NULL)
1148                                 || (ntohs(utag->tag_len) != sizeof(sp))) {
1149                                         LEAVE (ENETUNREACH);
1150                                         break;
1151                                 }
1152                                 sendhook = pppoe_finduniq(node, utag);
1153                                 if (sendhook == NULL) {
1154                                         LEAVE(ENETUNREACH);
1155                                 }
1156
1157                                 /*
1158                                  * Check the session is in the right state.
1159                                  * It needs to be in PPPOE_SREQ.
1160                                  */
1161                                 sp = sendhook->private;
1162                                 if (sp->state != PPPOE_SREQ) {
1163                                         LEAVE(ENETUNREACH);
1164                                 }
1165                                 neg = sp->neg;
1166                                 callout_stop(&neg->timeout_ch);
1167                                 neg->pkt->pkt_header.ph.sid = wh->ph.sid;
1168                                 sp->Session_ID = ntohs(wh->ph.sid);
1169                                 send_sessionid(sp);
1170                                 neg->timeout = 0;
1171                                 sp->state = PPPOE_CONNECTED;
1172                                 /*
1173                                  * Now we have gone to Connected mode,
1174                                  * Free all resources needed for
1175                                  * negotiation.
1176                                  * Keep a copy of the header we will be using.
1177                                  */
1178                                 sp->pkt_hdr = neg->pkt->pkt_header;
1179                                 if (pppoe_mode == PPPOE_NONSTANDARD)
1180                                         sp->pkt_hdr.eh.ether_type
1181                                                 = ETHERTYPE_PPPOE_STUPID_SESS;
1182                                 else
1183                                         sp->pkt_hdr.eh.ether_type
1184                                                 = ETHERTYPE_PPPOE_SESS;
1185                                 sp->pkt_hdr.ph.code = 0;
1186                                 m_freem(neg->m);
1187                                 FREE(sp->neg, M_NETGRAPH);
1188                                 sp->neg = NULL;
1189                                 pppoe_send_event(sp, NGM_PPPOE_SUCCESS);
1190                                 break;
1191                         case    PADT_CODE:
1192                                 /*
1193                                  * Send a 'close' message to the controlling
1194                                  * process (the one that set us up);
1195                                  * And then tear everything down.
1196                                  *
1197                                  * Find matching peer/session combination.
1198                                  */
1199                                 sendhook = pppoe_findsession(node, wh);
1200                                 NG_FREE_DATA(m, meta); /* no longer needed */
1201                                 if (sendhook == NULL) {
1202                                         LEAVE(ENETUNREACH);
1203                                 }
1204                                 /* send message to creator */
1205                                 /* close hook */
1206                                 if (sendhook) {
1207                                         ng_destroy_hook(sendhook);
1208                                 }
1209                                 break;
1210                         default:
1211                                 LEAVE(EPFNOSUPPORT);
1212                         }
1213                         break;
1214                 case    ETHERTYPE_PPPOE_STUPID_SESS:
1215                 case    ETHERTYPE_PPPOE_SESS:
1216                         /*
1217                          * find matching peer/session combination.
1218                          */
1219                         sendhook = pppoe_findsession(node, wh);
1220                         if (sendhook == NULL) {
1221                                 LEAVE (ENETUNREACH);
1222                                 break;
1223                         }
1224                         sp = sendhook->private;
1225                         m_adj(m, sizeof(*wh));
1226                         if (m->m_pkthdr.len < length) {
1227                                 /* Packet too short, dump it */
1228                                 LEAVE(EMSGSIZE);
1229                         }
1230
1231                         /* Also need to trim excess at the end */
1232                         if (m->m_pkthdr.len > length) {
1233                                 m_adj(m, -((int)(m->m_pkthdr.len - length)));
1234                         }
1235                         if ( sp->state != PPPOE_CONNECTED) {
1236                                 if (sp->state == PPPOE_NEWCONNECTED) {
1237                                         sp->state = PPPOE_CONNECTED;
1238                                         /*
1239                                          * Now we have gone to Connected mode,
1240                                          * Free all resources needed for
1241                                          * negotiation. Be paranoid about
1242                                          * whether there may be a timeout.
1243                                          */
1244                                         m_freem(sp->neg->m);
1245                                         callout_stop(&sp->neg->timeout_ch);
1246                                         FREE(sp->neg, M_NETGRAPH);
1247                                         sp->neg = NULL;
1248                                 } else {
1249                                         LEAVE (ENETUNREACH);
1250                                         break;
1251                                 }
1252                         }
1253                         NG_SEND_DATA( error, sendhook, m, meta);
1254                         break;
1255                 default:
1256                         LEAVE(EPFNOSUPPORT);
1257                 }
1258         } else {
1259                 /*
1260                  *      Not ethernet or debug hook..
1261                  *
1262                  * The packet has come in on a normal hook.
1263                  * We need to find out what kind of hook,
1264                  * So we can decide how to handle it.
1265                  * Check the hook's state.
1266                  */
1267                 sp = hook->private;
1268                 switch (sp->state) {
1269                 case    PPPOE_NEWCONNECTED:
1270                 case    PPPOE_CONNECTED: {
1271                         static const u_char addrctrl[] = { 0xff, 0x03 };
1272                         struct pppoe_full_hdr *wh;
1273
1274                         /*
1275                          * Remove PPP address and control fields, if any.
1276                          * For example, ng_ppp(4) always sends LCP packets
1277                          * with address and control fields as required by
1278                          * generic PPP. PPPoE is an exception to the rule.
1279                          */
1280                         if (m->m_pkthdr.len >= 2) {
1281                                 if (m->m_len < 2 && !(m = m_pullup(m, 2)))
1282                                         LEAVE(ENOBUFS);
1283                                 if (bcmp(mtod(m, u_char *), addrctrl, 2) == 0)
1284                                         m_adj(m, 2);
1285                         }
1286                         /*
1287                          * Bang in a pre-made header, and set the length up
1288                          * to be correct. Then send it to the ethernet driver.
1289                          * But first correct the length.
1290                          */
1291                         sp->pkt_hdr.ph.length = htons((short)(m->m_pkthdr.len));
1292                         M_PREPEND(m, sizeof(*wh), MB_DONTWAIT);
1293                         if (m == NULL) {
1294                                 LEAVE(ENOBUFS);
1295                         }
1296                         wh = mtod(m, struct pppoe_full_hdr *);
1297                         bcopy(&sp->pkt_hdr, wh, sizeof(*wh));
1298                         NG_SEND_DATA( error, privp->ethernet_hook, m, meta);
1299                         privp->packets_out++;
1300                         break;
1301                         }
1302                 case    PPPOE_PRIMED:
1303                         /*
1304                          * A PADI packet is being returned by the application
1305                          * that has set up this hook. This indicates that it
1306                          * wants us to offer service.
1307                          */
1308                         neg = sp->neg;
1309                         if (m->m_len < sizeof(*wh)) {
1310                                 m = m_pullup(m, sizeof(*wh));
1311                                 if (m == NULL) {
1312                                         LEAVE(ENOBUFS);
1313                                 }
1314                         }
1315                         wh = mtod(m, struct pppoe_full_hdr *);
1316                         ph = &wh->ph;
1317                         session = ntohs(wh->ph.sid);
1318                         length = ntohs(wh->ph.length);
1319                         code = wh->ph.code;
1320                         if ( code != PADI_CODE) {
1321                                 LEAVE(EINVAL);
1322                         };
1323                         callout_stop(&neg->timeout_ch);
1324
1325                         /*
1326                          * This is the first time we hear
1327                          * from the client, so note it's
1328                          * unicast address, replacing the
1329                          * broadcast address.
1330                          */
1331                         bcopy(wh->eh.ether_shost,
1332                                 neg->pkt->pkt_header.eh.ether_dhost,
1333                                 ETHER_ADDR_LEN);
1334                         sp->state = PPPOE_SOFFER;
1335                         neg->timeout = 0;
1336                         neg->pkt->pkt_header.ph.code = PADO_CODE;
1337
1338                         /*
1339                          * start working out the tags to respond with.
1340                          */
1341                         uniqtag.hdr.tag_type = PTT_AC_COOKIE;
1342                         uniqtag.hdr.tag_len = htons((u_int16_t)sizeof(sp));
1343                         uniqtag.data.pointer = sp;
1344                         init_tags(sp);
1345                         insert_tag(sp, &neg->ac_name.hdr); /* AC_NAME */
1346                         if ((tag = get_tag(ph, PTT_SRV_NAME)))
1347                                 insert_tag(sp, tag);      /* return service */
1348                         /*
1349                          * If we have a NULL service request
1350                          * and have an extra service defined in this hook,
1351                          * then also add a tag for the extra service.
1352                          * XXX this is a hack. eventually we should be able
1353                          * to support advertising many services, not just one
1354                          */
1355                         if (((tag == NULL) || (tag->tag_len == 0))
1356                         && (neg->service.hdr.tag_len != 0)) {
1357                                 insert_tag(sp, &neg->service.hdr); /* SERVICE */
1358                         }
1359                         if ((tag = get_tag(ph, PTT_HOST_UNIQ)))
1360                                 insert_tag(sp, tag); /* returned hostunique */
1361                         insert_tag(sp, &uniqtag.hdr);
1362                         scan_tags(sp, ph);
1363                         make_packet(sp);
1364                         sendpacket(sp);
1365                         break;
1366
1367                 /*
1368                  * Packets coming from the hook make no sense
1369                  * to sessions in these states. Throw them away.
1370                  */
1371                 case    PPPOE_SINIT:
1372                 case    PPPOE_SREQ:
1373                 case    PPPOE_SOFFER:
1374                 case    PPPOE_SNONE:
1375                 case    PPPOE_LISTENING:
1376                 case    PPPOE_DEAD:
1377                 default:
1378                         LEAVE(ENETUNREACH);
1379                 }
1380         }
1381 quit:
1382         NG_FREE_DATA(m, meta);
1383         return error;
1384 }
1385
1386 /*
1387  * Do local shutdown processing..
1388  * If we are a persistant device, we might refuse to go away, and
1389  * we'd only remove our links and reset ourself.
1390  */
1391 static int
1392 ng_pppoe_rmnode(node_p node)
1393 {
1394         const priv_p privdata = node->private;
1395
1396 AAA
1397         node->flags |= NG_INVALID;
1398         ng_cutlinks(node);
1399         ng_unname(node);
1400         node->private = NULL;
1401         ng_unref(privdata->node);
1402         FREE(privdata, M_NETGRAPH);
1403         return (0);
1404 }
1405
1406 /*
1407  * This is called once we've already connected a new hook to the other node.
1408  * It gives us a chance to balk at the last minute.
1409  */
1410 static int
1411 ng_pppoe_connect(hook_p hook)
1412 {
1413         /* be really amiable and just say "YUP that's OK by me! " */
1414         return (0);
1415 }
1416
1417 /*
1418  * Hook disconnection
1419  *
1420  * Clean up all dangling links and information about the session/hook.
1421  * For this type, removal of the last link destroys the node
1422  */
1423 static int
1424 ng_pppoe_disconnect(hook_p hook)
1425 {
1426         node_p node = hook->node;
1427         priv_p privp = node->private;
1428         sessp   sp;
1429         int     hooks;
1430
1431 AAA
1432         hooks = node->numhooks; /* this one already not counted */
1433         if (hook->private == &privp->debug_hook) {
1434                 privp->debug_hook = NULL;
1435         } else if (hook->private == &privp->ethernet_hook) {
1436                 privp->ethernet_hook = NULL;
1437                 ng_rmnode(node);
1438         } else {
1439                 sp = hook->private;
1440                 if (sp->state != PPPOE_SNONE ) {
1441                         pppoe_send_event(sp, NGM_PPPOE_CLOSE);
1442                 }
1443                 /*
1444                  * According to the spec, if we are connected,
1445                  * we should send a DISC packet if we are shutting down
1446                  * a session.
1447                  */
1448                 if ((privp->ethernet_hook)
1449                 && ((sp->state == PPPOE_CONNECTED)
1450                  || (sp->state == PPPOE_NEWCONNECTED))) {
1451                         struct mbuf *m;
1452                         struct pppoe_full_hdr *wh;
1453                         struct pppoe_tag *tag;
1454                         int     msglen = strlen(SIGNOFF);
1455                         void *dummy = NULL;
1456                         int error = 0;
1457
1458                         /* revert the stored header to DISC/PADT mode */
1459                         wh = &sp->pkt_hdr;
1460                         wh->ph.code = PADT_CODE;
1461                         if (pppoe_mode == PPPOE_NONSTANDARD)
1462                                 wh->eh.ether_type = ETHERTYPE_PPPOE_STUPID_DISC;
1463                         else
1464                                 wh->eh.ether_type = ETHERTYPE_PPPOE_DISC;
1465
1466                         /* generate a packet of that type */
1467                         MGETHDR(m, MB_DONTWAIT, MT_DATA);
1468                         if(m == NULL)
1469                                 printf("pppoe: Session out of mbufs\n");
1470                         else {
1471                                 m->m_pkthdr.rcvif = NULL;
1472                                 m->m_pkthdr.len = m->m_len = sizeof(*wh);
1473                                 bcopy((caddr_t)wh, mtod(m, caddr_t),
1474                                     sizeof(*wh));
1475                                 /*
1476                                  * Add a General error message and adjust
1477                                  * sizes
1478                                  */
1479                                 wh = mtod(m, struct pppoe_full_hdr *);
1480                                 tag = wh->ph.tag;
1481                                 tag->tag_type = PTT_GEN_ERR;
1482                                 tag->tag_len = htons((u_int16_t)msglen);
1483                                 strncpy(tag->tag_data, SIGNOFF, msglen);
1484                                 m->m_pkthdr.len = (m->m_len += sizeof(*tag) +
1485                                     msglen);
1486                                 wh->ph.length = htons(sizeof(*tag) + msglen);
1487                                 NG_SEND_DATA(error, privp->ethernet_hook, m,
1488                                     dummy);
1489                         }
1490                 }
1491                 /*
1492                  * As long as we have somewhere to store the timeout handle,
1493                  * we may have a timeout pending.. get rid of it.
1494                  */
1495                 if (sp->neg) {
1496                         callout_stop(&sp->neg->timeout_ch);
1497                         if (sp->neg->m)
1498                                 m_freem(sp->neg->m);
1499                         FREE(sp->neg, M_NETGRAPH);
1500                 }
1501                 FREE(sp, M_NETGRAPH);
1502                 hook->private = NULL;
1503                 /* work out how many session hooks there are */
1504                 /* Node goes away on last session hook removal */
1505                 if (privp->ethernet_hook) hooks -= 1;
1506                 if (privp->debug_hook) hooks -= 1;
1507         }
1508         if (node->numhooks == 0)
1509                 ng_rmnode(node);
1510         return (0);
1511 }
1512
1513 /*
1514  * timeouts come here.
1515  */
1516 static void
1517 pppoe_ticker(void *arg)
1518 {
1519         hook_p hook = arg;
1520         sessp   sp = hook->private;
1521         negp    neg = sp->neg;
1522         int     error = 0;
1523         struct mbuf *m0 = NULL;
1524         priv_p privp = hook->node->private;
1525         meta_p dummy = NULL;
1526
1527         crit_enter();
1528 AAA
1529         switch(sp->state) {
1530                 /*
1531                  * resend the last packet, using an exponential backoff.
1532                  * After a period of time, stop growing the backoff,
1533                  * and either leave it, or revert to the start.
1534                  */
1535         case    PPPOE_SINIT:
1536         case    PPPOE_SREQ:
1537                 /* timeouts on these produce resends */
1538                 m0 = m_copypacket(sp->neg->m, MB_DONTWAIT);
1539                 NG_SEND_DATA( error, privp->ethernet_hook, m0, dummy);
1540                 callout_reset(&neg->timeout_ch, neg->timeout * hz,
1541                                 pppoe_ticker, hook);
1542                 if ((neg->timeout <<= 1) > PPPOE_TIMEOUT_LIMIT) {
1543                         if (sp->state == PPPOE_SREQ) {
1544                                 /* revert to SINIT mode */
1545                                 pppoe_start(sp);
1546                         } else {
1547                                 neg->timeout = PPPOE_TIMEOUT_LIMIT;
1548                         }
1549                 }
1550                 break;
1551         case    PPPOE_PRIMED:
1552         case    PPPOE_SOFFER:
1553                 /* a timeout on these says "give up" */
1554                 ng_destroy_hook(hook);
1555                 break;
1556         default:
1557                 /* timeouts have no meaning in other states */
1558                 printf("pppoe: unexpected timeout\n");
1559         }
1560         crit_exit();
1561 }
1562
1563
1564 static void
1565 sendpacket(sessp sp)
1566 {
1567         int     error = 0;
1568         struct mbuf *m0 = NULL;
1569         hook_p hook = sp->hook;
1570         negp    neg = sp->neg;
1571         priv_p  privp = hook->node->private;
1572         meta_p dummy = NULL;
1573
1574 AAA
1575         switch(sp->state) {
1576         case    PPPOE_LISTENING:
1577         case    PPPOE_DEAD:
1578         case    PPPOE_SNONE:
1579         case    PPPOE_CONNECTED:
1580                 printf("pppoe: sendpacket: unexpected state\n");
1581                 break;
1582
1583         case    PPPOE_NEWCONNECTED:
1584                 /* send the PADS without a timeout - we're now connected */
1585                 m0 = m_copypacket(sp->neg->m, MB_DONTWAIT);
1586                 NG_SEND_DATA( error, privp->ethernet_hook, m0, dummy);
1587                 break;
1588
1589         case    PPPOE_PRIMED:
1590                 /* No packet to send, but set up the timeout */
1591                 callout_reset(&neg->timeout_ch, PPPOE_OFFER_TIMEOUT * hz,
1592                                 pppoe_ticker, hook);
1593                 break;
1594
1595         case    PPPOE_SOFFER:
1596                 /*
1597                  * send the offer but if they don't respond
1598                  * in PPPOE_OFFER_TIMEOUT seconds, forget about it.
1599                  */
1600                 m0 = m_copypacket(sp->neg->m, MB_DONTWAIT);
1601                 NG_SEND_DATA( error, privp->ethernet_hook, m0, dummy);
1602                 callout_reset(&neg->timeout_ch, PPPOE_OFFER_TIMEOUT * hz,
1603                                 pppoe_ticker, hook);
1604                 break;
1605
1606         case    PPPOE_SINIT:
1607         case    PPPOE_SREQ:
1608                 m0 = m_copypacket(sp->neg->m, MB_DONTWAIT);
1609                 NG_SEND_DATA( error, privp->ethernet_hook, m0, dummy);
1610                 callout_reset(&neg->timeout_ch, PPPOE_INITIAL_TIMEOUT * hz,
1611                                 pppoe_ticker, hook);
1612                 neg->timeout = PPPOE_INITIAL_TIMEOUT * 2;
1613                 break;
1614
1615         default:
1616                 error = EINVAL;
1617                 printf("pppoe: timeout: bad state\n");
1618         }
1619         /* return (error); */
1620 }
1621
1622 /*
1623  * Parse an incoming packet to see if any tags should be copied to the
1624  * output packet. Don't do any tags that have been handled in the main
1625  * state machine.
1626  */
1627 static const struct pppoe_tag*
1628 scan_tags(sessp sp, const struct pppoe_hdr* ph)
1629 {
1630         const char *const end = (const char *)next_tag(ph);
1631         const char *ptn;
1632         const struct pppoe_tag *pt = &ph->tag[0];
1633         /*
1634          * Keep processing tags while a tag header will still fit.
1635          */
1636 AAA
1637         while((const char*)(pt + 1) <= end) {
1638                 /*
1639                  * If the tag data would go past the end of the packet, abort.
1640                  */
1641                 ptn = (((const char *)(pt + 1)) + ntohs(pt->tag_len));
1642                 if(ptn > end)
1643                         return NULL;
1644
1645                 switch (pt->tag_type) {
1646                 case    PTT_RELAY_SID:
1647                         insert_tag(sp, pt);
1648                         break;
1649                 case    PTT_EOL:
1650                         return NULL;
1651                 case    PTT_SRV_NAME:
1652                 case    PTT_AC_NAME:
1653                 case    PTT_HOST_UNIQ:
1654                 case    PTT_AC_COOKIE:
1655                 case    PTT_VENDOR:
1656                 case    PTT_SRV_ERR:
1657                 case    PTT_SYS_ERR:
1658                 case    PTT_GEN_ERR:
1659                         break;
1660                 }
1661                 pt = (const struct pppoe_tag*)ptn;
1662         }
1663         return NULL;
1664 }
1665
1666 static  int
1667 pppoe_send_event(sessp sp, enum cmd cmdid)
1668 {
1669         int error;
1670         struct ng_mesg *msg;
1671         struct ngpppoe_sts *sts;
1672
1673 AAA
1674         NG_MKMESSAGE(msg, NGM_PPPOE_COOKIE, cmdid,
1675                         sizeof(struct ngpppoe_sts), M_NOWAIT);
1676         if (msg == NULL)
1677                 return (ENOMEM);
1678         sts = (struct ngpppoe_sts *)msg->data;
1679         strncpy(sts->hook, sp->hook->name, NG_HOOKLEN + 1);
1680         error = ng_send_msg(sp->hook->node, msg, sp->creator, NULL);
1681         return (error);
1682 }