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 1.5 2004/06/02 14:43:00 eirikn 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", __FUNCTION__ );
  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 <net/ethernet.h>
  60
  61 #include <netgraph/ng_message.h>
  62 #include <netgraph/netgraph.h>
  63 #include "ng_pppoe.h"
  64
  65 #define SIGNOFF "session closed"
  66
  67 /*
  68  * This section contains the netgraph method declarations for the
  69  * pppoe node. These methods define the netgraph pppoe 'type'.
  70  */
  71
  72 static ng_constructor_t ng_pppoe_constructor;
  73 static ng_rcvmsg_t      ng_pppoe_rcvmsg;
  74 static ng_shutdown_t    ng_pppoe_rmnode;
  75 static ng_newhook_t     ng_pppoe_newhook;
  76 static ng_connect_t     ng_pppoe_connect;
  77 static ng_rcvdata_t     ng_pppoe_rcvdata;
  78 static ng_disconnect_t  ng_pppoe_disconnect;
  79
  80 /* Netgraph node type descriptor */
  81 static struct ng_type typestruct = {
  82         NG_VERSION,
  83         NG_PPPOE_NODE_TYPE,
  84         NULL,
  85         ng_pppoe_constructor,
  86         ng_pppoe_rcvmsg,
  87         ng_pppoe_rmnode,
  88         ng_pppoe_newhook,
  89         NULL,
  90         ng_pppoe_connect,
  91         ng_pppoe_rcvdata,
  92         ng_pppoe_rcvdata,
  93         ng_pppoe_disconnect,
  94         NULL
  95 };
  96 NETGRAPH_INIT(pppoe, &typestruct);
  97
  98 /*
  99  * States for the session state machine.
 100  * These have no meaning if there is no hook attached yet.
 101  */
 102 enum state {
 103     PPPOE_SNONE=0,      /* [both] Initial state */
 104     PPPOE_LISTENING,    /* [Daemon] Listening for discover initiation pkt */
 105     PPPOE_SINIT,        /* [Client] Sent discovery initiation */
 106     PPPOE_PRIMED,       /* [Server] Awaiting PADI from daemon */
 107     PPPOE_SOFFER,       /* [Server] Sent offer message  (got PADI)*/
 108     PPPOE_SREQ,         /* [Client] Sent a Request */
 109     PPPOE_NEWCONNECTED, /* [Server] Connection established, No data received */
 110     PPPOE_CONNECTED,    /* [Both] Connection established, Data received */
 111     PPPOE_DEAD          /* [Both] */
 112 };
 113
 114 #define NUMTAGS 20 /* number of tags we are set up to work with */
 115
 116 /*
 117  * Information we store for each hook on each node for negotiating the
 118  * session. The mbuf and cluster are freed once negotiation has completed.
 119  * The whole negotiation block is then discarded.
 120  */
 121
 122 struct sess_neg {
 123         struct mbuf             *m; /* holds cluster with last sent packet */
 124         union   packet          *pkt; /* points within the above cluster */
 125         struct callout_handle   timeout_handle;   /* see timeout(9) */
 126         u_int                   timeout; /* 0,1,2,4,8,16 etc. seconds */
 127         u_int                   numtags;
 128         const struct pppoe_tag  *tags[NUMTAGS];
 129         u_int                   service_len;
 130         u_int                   ac_name_len;
 131
 132         struct datatag          service;
 133         struct datatag          ac_name;
 134 };
 135 typedef struct sess_neg *negp;
 136
 137 /*
 138  * Session information that is needed after connection.
 139  */
 140 struct sess_con {
 141         hook_p                  hook;
 142         u_int16_t               Session_ID;
 143         enum state              state;
 144         char                    creator[NG_NODELEN + 1]; /* who to notify */
 145         struct pppoe_full_hdr   pkt_hdr;        /* used when connected */
 146         negp                    neg;            /* used when negotiating */
 147         /*struct sess_con       *hash_next;*/   /* not yet used */
 148 };
 149 typedef struct sess_con *sessp;
 150
 151 /*
 152  * Information we store for each node
 153  */
 154 struct PPPOE {
 155         node_p          node;           /* back pointer to node */
 156         hook_p          ethernet_hook;
 157         hook_p          debug_hook;
 158         u_int           packets_in;     /* packets in from ethernet */
 159         u_int           packets_out;    /* packets out towards ethernet */
 160         u_int32_t       flags;
 161         /*struct sess_con *buckets[HASH_SIZE];*/        /* not yet used */
 162 };
 163 typedef struct PPPOE *priv_p;
 164
 165 struct ether_header eh_prototype =
 166         {{0xff,0xff,0xff,0xff,0xff,0xff},
 167          {0x00,0x00,0x00,0x00,0x00,0x00},
 168          ETHERTYPE_PPPOE_DISC};
 169
 170 #define PPPOE_KEEPSTANDARD      -1      /* never switch to nonstandard mode */
 171 #define PPPOE_STANDARD          0       /* try standard mode (dangerous!) */
 172 #define PPPOE_NONSTANDARD       1       /* just be in nonstandard mode */
 173 static int pppoe_mode = PPPOE_KEEPSTANDARD;
 174
 175 static int
 176 ngpppoe_set_ethertype(SYSCTL_HANDLER_ARGS)
 177 {
 178         int error;
 179         int val;
 180
 181         val = pppoe_mode;
 182         error = sysctl_handle_int(oidp, &val, sizeof(int), req);
 183         if (error != 0 || req->newptr == NULL)
 184                 return (error);
 185         switch (val) {
 186         case PPPOE_NONSTANDARD:
 187                 pppoe_mode = PPPOE_NONSTANDARD;
 188                 eh_prototype.ether_type = ETHERTYPE_PPPOE_STUPID_DISC;
 189                 break;
 190         case PPPOE_STANDARD:
 191                 pppoe_mode = PPPOE_STANDARD;
 192                 eh_prototype.ether_type = ETHERTYPE_PPPOE_DISC;
 193                 break;
 194         case PPPOE_KEEPSTANDARD:
 195                 pppoe_mode = PPPOE_KEEPSTANDARD;
 196                 eh_prototype.ether_type = ETHERTYPE_PPPOE_DISC;
 197                 break;
 198         default:
 199                 return (EINVAL);
 200         }
 201         return (0);
 202 }
 203
 204 SYSCTL_PROC(_net_graph, OID_AUTO, nonstandard_pppoe, CTLTYPE_INT | CTLFLAG_RW,
 205     0, sizeof(int), ngpppoe_set_ethertype, "I", "nonstandard ethertype");
 206
 207 union uniq {
 208         char bytes[sizeof(void *)];
 209         void * pointer;
 210         };
 211
 212 #define LEAVE(x) do { error = x; goto quit; } while(0)
 213 static void     pppoe_start(sessp sp);
 214 static void     sendpacket(sessp sp);
 215 static void     pppoe_ticker(void *arg);
 216 static const    struct pppoe_tag *scan_tags(sessp sp,
 217                         const struct pppoe_hdr* ph);
 218 static  int     pppoe_send_event(sessp sp, enum cmd cmdid);
 219
 220 /*************************************************************************
 221  * Some basic utilities  from the Linux version with author's permission.*
 222  * Author:      Michal Ostrowski <mostrows@styx.uwaterloo.ca>            *
 223  ************************************************************************/
 224
 225 /*
 226  * Generate a new session id
 227  * XXX find out the FreeBSD locking scheme.
 228  */
 229 static u_int16_t
 230 get_new_sid(node_p node)
 231 {
 232         static int pppoe_sid = 10;
 233         sessp sp;
 234         hook_p  hook;
 235         u_int16_t val;
 236         priv_p privp = node->private;
 237
 238 AAA
 239 restart:
 240         val = pppoe_sid++;
 241         /*
 242          * Spec says 0xFFFF is reserved.
 243          * Also don't use 0x0000
 244          */
 245         if (val == 0xffff) {
 246                 pppoe_sid = 20;
 247                 goto restart;
 248         }
 249
 250         /* Check it isn't already in use */
 251         LIST_FOREACH(hook, &node->hooks, hooks) {
 252                 /* don't check special hooks */
 253                 if ((hook->private == &privp->debug_hook)
 254                 ||  (hook->private == &privp->ethernet_hook))
 255                         continue;
 256                 sp = hook->private;
 257                 if (sp->Session_ID == val)
 258                         goto restart;
 259         }
 260
 261         return val;
 262 }
 263
 264
 265 /*
 266  * Return the location where the next tag can be put
 267  */
 268 static __inline const struct pppoe_tag*
 269 next_tag(const struct pppoe_hdr* ph)
 270 {
 271         return (const struct pppoe_tag*)(((const char*)&ph->tag[0])
 272             + ntohs(ph->length));
 273 }
 274
 275 /*
 276  * Look for a tag of a specific type
 277  * Don't trust any length the other end says.
 278  * but assume we already sanity checked ph->length.
 279  */
 280 static const struct pppoe_tag*
 281 get_tag(const struct pppoe_hdr* ph, u_int16_t idx)
 282 {
 283         const char *const end = (const char *)next_tag(ph);
 284         const char *ptn;
 285         const struct pppoe_tag *pt = &ph->tag[0];
 286         /*
 287          * Keep processing tags while a tag header will still fit.
 288          */
 289 AAA
 290         while((const char*)(pt + 1) <= end) {
 291             /*
 292              * If the tag data would go past the end of the packet, abort.
 293              */
 294             ptn = (((const char *)(pt + 1)) + ntohs(pt->tag_len));
 295             if(ptn > end)
 296                 return NULL;
 297
 298             if(pt->tag_type == idx)
 299                 return pt;
 300
 301             pt = (const struct pppoe_tag*)ptn;
 302         }
 303         return NULL;
 304 }
 305
 306 /**************************************************************************
 307  * inlines to initialise or add tags to a session's tag list,
 308  **************************************************************************/
 309 /*
 310  * Initialise the session's tag list
 311  */
 312 static void
 313 init_tags(sessp sp)
 314 {
 315 AAA
 316         if(sp->neg == NULL) {
 317                 printf("pppoe: asked to init NULL neg pointer\n");
 318                 return;
 319         }
 320         sp->neg->numtags = 0;
 321 }
 322
 323 static void
 324 insert_tag(sessp sp, const struct pppoe_tag *tp)
 325 {
 326         int     i;
 327         negp neg;
 328
 329 AAA
 330         if((neg = sp->neg) == NULL) {
 331                 printf("pppoe: asked to use NULL neg pointer\n");
 332                 return;
 333         }
 334         if ((i = neg->numtags++) < NUMTAGS) {
 335                 neg->tags[i] = tp;
 336         } else {
 337                 printf("pppoe: asked to add too many tags to packet\n");
 338                 neg->numtags--;
 339         }
 340 }
 341
 342 /*
 343  * Make up a packet, using the tags filled out for the session.
 344  *
 345  * Assume that the actual pppoe header and ethernet header
 346  * are filled out externally to this routine.
 347  * Also assume that neg->wh points to the correct
 348  * location at the front of the buffer space.
 349  */
 350 static void
 351 make_packet(sessp sp) {
 352         struct pppoe_full_hdr *wh = &sp->neg->pkt->pkt_header;
 353         const struct pppoe_tag **tag;
 354         char *dp;
 355         int count;
 356         int tlen;
 357         u_int16_t length = 0;
 358
 359 AAA
 360         if ((sp->neg == NULL) || (sp->neg->m == NULL)) {
 361                 printf("pppoe: make_packet called from wrong state\n");
 362         }
 363         dp = (char *)wh->ph.tag;
 364         for (count = 0, tag = sp->neg->tags;
 365             ((count < sp->neg->numtags) && (count < NUMTAGS));
 366             tag++, count++) {
 367                 tlen = ntohs((*tag)->tag_len) + sizeof(**tag);
 368                 if ((length + tlen) > (ETHER_MAX_LEN - 4 - sizeof(*wh))) {
 369                         printf("pppoe: tags too long\n");
 370                         sp->neg->numtags = count;
 371                         break;  /* XXX chop off what's too long */
 372                 }
 373                 bcopy(*tag, (char *)dp, tlen);
 374                 length += tlen;
 375                 dp += tlen;
 376         }
 377         wh->ph.length = htons(length);
 378         sp->neg->m->m_len = length + sizeof(*wh);
 379         sp->neg->m->m_pkthdr.len = length + sizeof(*wh);
 380 }
 381
 382 /**************************************************************************
 383  * Routine to match a service offered                                     *
 384  **************************************************************************/
 385 /*
 386  * Find a hook that has a service string that matches that
 387  * we are seeking. for now use a simple string.
 388  * In the future we may need something like regexp().
 389  * for testing allow a null string to match 1st found and a null service
 390  * to match all requests. Also make '*' do the same.
 391  */
 392
 393 #define NG_MATCH_EXACT  1
 394 #define NG_MATCH_ANY    2
 395
 396 static hook_p
 397 pppoe_match_svc(node_p node, const char *svc_name, int svc_len, int match)
 398 {
 399         sessp   sp      = NULL;
 400         negp    neg     = NULL;
 401         priv_p  privp   = node->private;
 402         hook_p  allhook = NULL;
 403         hook_p  hook;
 404
 405 AAA
 406         LIST_FOREACH(hook, &node->hooks, hooks) {
 407
 408                 /* skip any hook that is debug or ethernet */
 409                 if ((hook->private == &privp->debug_hook)
 410                 ||  (hook->private == &privp->ethernet_hook))
 411                         continue;
 412                 sp = hook->private;
 413
 414                 /* Skip any sessions which are not in LISTEN mode. */
 415                 if ( sp->state != PPPOE_LISTENING)
 416                         continue;
 417
 418                 neg = sp->neg;
 419
 420                 /* Special case for a blank or "*" service name (wildcard) */
 421                 if (match == NG_MATCH_ANY && neg->service_len == 1 &&
 422                     neg->service.data[0] == '*') {
 423                         allhook = hook;
 424                         continue;
 425                 }
 426
 427                 /* If the lengths don't match, that aint it. */
 428                 if (neg->service_len != svc_len)
 429                         continue;
 430
 431                 /* An exact match? */
 432                 if (svc_len == 0)
 433                         break;
 434
 435                 if (strncmp(svc_name, neg->service.data, svc_len) == 0)
 436                         break;
 437         }
 438         return (hook ? hook : allhook);
 439 }
 440 /**************************************************************************
 441  * Routine to find a particular session that matches an incoming packet   *
 442  **************************************************************************/
 443 static hook_p
 444 pppoe_findsession(node_p node, const struct pppoe_full_hdr *wh)
 445 {
 446         sessp   sp = NULL;
 447         hook_p hook = NULL;
 448         priv_p  privp = node->private;
 449         u_int16_t       session = ntohs(wh->ph.sid);
 450
 451         /*
 452          * find matching peer/session combination.
 453          */
 454 AAA
 455         LIST_FOREACH(hook, &node->hooks, hooks) {
 456                 /* don't check special hooks */
 457                 if ((hook->private == &privp->debug_hook)
 458                 ||  (hook->private == &privp->ethernet_hook)) {
 459                         continue;
 460                 }
 461                 sp = hook->private;
 462                 if ( ( (sp->state == PPPOE_CONNECTED)
 463                     || (sp->state == PPPOE_NEWCONNECTED) )
 464                 && (sp->Session_ID == session)
 465                 && (bcmp(sp->pkt_hdr.eh.ether_dhost,
 466                     wh->eh.ether_shost,
 467                     ETHER_ADDR_LEN)) == 0) {
 468                         break;
 469                 }
 470         }
 471         return (hook);
 472 }
 473
 474 static hook_p
 475 pppoe_finduniq(node_p node, const struct pppoe_tag *tag)
 476 {
 477         hook_p hook = NULL;
 478         priv_p  privp = node->private;
 479         union uniq              uniq;
 480
 481 AAA
 482         bcopy(tag->tag_data, uniq.bytes, sizeof(void *));
 483         /* cycle through all known hooks */
 484         LIST_FOREACH(hook, &node->hooks, hooks) {
 485                 /* don't check special hooks */
 486                 if ((hook->private == &privp->debug_hook)
 487                 ||  (hook->private == &privp->ethernet_hook))
 488                         continue;
 489                 if (uniq.pointer == hook->private)
 490                         break;
 491         }
 492         return (hook);
 493 }
 494
 495 /**************************************************************************
 496  * start of Netgraph entrypoints                                          *
 497  **************************************************************************/
 498
 499 /*
 500  * Allocate the private data structure and the generic node
 501  * and link them together.
 502  *
 503  * ng_make_node_common() returns with a generic node struct
 504  * with a single reference for us.. we transfer it to the
 505  * private structure.. when we free the private struct we must
 506  * unref the node so it gets freed too.
 507  */
 508 static int
 509 ng_pppoe_constructor(node_p *nodep)
 510 {
 511         priv_p privdata;
 512         int error;
 513
 514 AAA
 515         /* Initialize private descriptor */
 516         MALLOC(privdata, priv_p, sizeof(*privdata), M_NETGRAPH, M_NOWAIT);
 517         if (privdata == NULL)
 518                 return (ENOMEM);
 519         bzero(privdata, sizeof(*privdata));
 520
 521         /* Call the 'generic' (ie, superclass) node constructor */
 522         if ((error = ng_make_node_common(&typestruct, nodep))) {
 523                 FREE(privdata, M_NETGRAPH);
 524                 return (error);
 525         }
 526
 527         /* Link structs together; this counts as our one reference to *nodep */
 528         (*nodep)->private = privdata;
 529         privdata->node = *nodep;
 530         return (0);
 531 }
 532
 533 /*
 534  * Give our ok for a hook to be added...
 535  * point the hook's private info to the hook structure.
 536  *
 537  * The following hook names are special:
 538  *  Ethernet:  the hook that should be connected to a NIC.
 539  *  debug:      copies of data sent out here  (when I write the code).
 540  * All other hook names need only be unique. (the framework checks this).
 541  */
 542 static int
 543 ng_pppoe_newhook(node_p node, hook_p hook, const char *name)
 544 {
 545         const priv_p privp = node->private;
 546         sessp sp;
 547
 548 AAA
 549         if (strcmp(name, NG_PPPOE_HOOK_ETHERNET) == 0) {
 550                 privp->ethernet_hook = hook;
 551                 hook->private = &privp->ethernet_hook;
 552         } else if (strcmp(name, NG_PPPOE_HOOK_DEBUG) == 0) {
 553                 privp->debug_hook = hook;
 554                 hook->private = &privp->debug_hook;
 555         } else {
 556                 /*
 557                  * Any other unique name is OK.
 558                  * The infrastructure has already checked that it's unique,
 559                  * so just allocate it and hook it in.
 560                  */
 561                 MALLOC(sp, sessp, sizeof(*sp), M_NETGRAPH, M_NOWAIT);
 562                 if (sp == NULL) {
 563                                 return (ENOMEM);
 564                 }
 565                 bzero(sp, sizeof(*sp));
 566
 567                 hook->private = sp;
 568                 sp->hook = hook;
 569         }
 570         return(0);
 571 }
 572
 573 /*
 574  * Get a netgraph control message.
 575  * Check it is one we understand. If needed, send a response.
 576  * We sometimes save the address for an async action later.
 577  * Always free the message.
 578  */
 579 static int
 580 ng_pppoe_rcvmsg(node_p node,
 581            struct ng_mesg *msg, const char *retaddr, struct ng_mesg **rptr)
 582 {
 583         priv_p privp = node->private;
 584         struct ngpppoe_init_data *ourmsg = NULL;
 585         struct ng_mesg *resp = NULL;
 586         int error = 0;
 587         hook_p hook = NULL;
 588         sessp sp = NULL;
 589         negp neg = NULL;
 590
 591 AAA
 592         /* Deal with message according to cookie and command */
 593         switch (msg->header.typecookie) {
 594         case NGM_PPPOE_COOKIE:
 595                 switch (msg->header.cmd) {
 596                 case NGM_PPPOE_CONNECT:
 597                 case NGM_PPPOE_LISTEN:
 598                 case NGM_PPPOE_OFFER:
 599                 case NGM_PPPOE_SERVICE:
 600                         ourmsg = (struct ngpppoe_init_data *)msg->data;
 601                         if (( sizeof(*ourmsg) > msg->header.arglen)
 602                         || ((sizeof(*ourmsg) + ourmsg->data_len)
 603                             > msg->header.arglen)) {
 604                                 printf("pppoe_rcvmsg: bad arg size");
 605                                 LEAVE(EMSGSIZE);
 606                         }
 607                         if (ourmsg->data_len > PPPOE_SERVICE_NAME_SIZE) {
 608                                 printf("pppoe: init data too long (%d)\n",
 609                                                         ourmsg->data_len);
 610                                 LEAVE(EMSGSIZE);
 611                         }
 612                         /* make sure strcmp will terminate safely */
 613                         ourmsg->hook[sizeof(ourmsg->hook) - 1] = '\0';
 614
 615                         /* cycle through all known hooks */
 616                         LIST_FOREACH(hook, &node->hooks, hooks) {
 617                                 if (hook->name
 618                                 && strcmp(hook->name, ourmsg->hook) == 0)
 619                                         break;
 620                         }
 621                         if (hook == NULL) {
 622                                 LEAVE(ENOENT);
 623                         }
 624                         if ((hook->private == &privp->debug_hook)
 625                         ||  (hook->private == &privp->ethernet_hook)) {
 626                                 LEAVE(EINVAL);
 627                         }
 628                         sp = hook->private;
 629
 630                         if (msg->header.cmd == NGM_PPPOE_LISTEN) {
 631                                 /*
 632                                  * Ensure we aren't already listening for this
 633                                  * service.
 634                                  */
 635                                 if (pppoe_match_svc(node, ourmsg->data,
 636                                     ourmsg->data_len, NG_MATCH_EXACT) != NULL) {
 637                                         LEAVE(EEXIST);
 638                                 }
 639                         }
 640
 641                         /*
 642                          * PPPOE_SERVICE advertisments are set up
 643                          * on sessions that are in PRIMED state.
 644                          */
 645                         if (msg->header.cmd == NGM_PPPOE_SERVICE) {
 646                                 break;
 647                         }
 648                         if (sp->state |= PPPOE_SNONE) {
 649                                 printf("pppoe: Session already active\n");
 650                                 LEAVE(EISCONN);
 651                         }
 652
 653                         /*
 654                          * set up prototype header
 655                          */
 656                         MALLOC(neg, negp, sizeof(*neg), M_NETGRAPH, M_NOWAIT);
 657
 658                         if (neg == NULL) {
 659                                 printf("pppoe: Session out of memory\n");
 660                                 LEAVE(ENOMEM);
 661                         }
 662                         bzero(neg, sizeof(*neg));
 663                         MGETHDR(neg->m, MB_DONTWAIT, MT_DATA);
 664                         if(neg->m == NULL) {
 665                                 printf("pppoe: Session out of mbufs\n");
 666                                 FREE(neg, M_NETGRAPH);
 667                                 LEAVE(ENOBUFS);
 668                         }
 669                         neg->m->m_pkthdr.rcvif = NULL;
 670                         MCLGET(neg->m, MB_DONTWAIT);
 671                         if ((neg->m->m_flags & M_EXT) == 0) {
 672                                 printf("pppoe: Session out of mcls\n");
 673                                 m_freem(neg->m);
 674                                 FREE(neg, M_NETGRAPH);
 675                                 LEAVE(ENOBUFS);
 676                         }
 677                         sp->neg = neg;
 678                         callout_handle_init( &neg->timeout_handle);
 679                         neg->m->m_len = sizeof(struct pppoe_full_hdr);
 680                         neg->pkt = mtod(neg->m, union packet*);
 681                         neg->pkt->pkt_header.eh = eh_prototype;
 682                         neg->pkt->pkt_header.ph.ver = 0x1;
 683                         neg->pkt->pkt_header.ph.type = 0x1;
 684                         neg->pkt->pkt_header.ph.sid = 0x0000;
 685                         neg->timeout = 0;
 686
 687                         strncpy(sp->creator, retaddr, NG_NODELEN);
 688                         sp->creator[NG_NODELEN] = '\0';
 689                 }
 690                 switch (msg->header.cmd) {
 691                 case NGM_PPPOE_GET_STATUS:
 692                     {
 693                         struct ngpppoestat *stats;
 694
 695                         NG_MKRESPONSE(resp, msg, sizeof(*stats), M_NOWAIT);
 696                         if (!resp) {
 697                                 LEAVE(ENOMEM);
 698                         }
 699                         stats = (struct ngpppoestat *) resp->data;
 700                         stats->packets_in = privp->packets_in;
 701                         stats->packets_out = privp->packets_out;
 702                         break;
 703                     }
 704                 case NGM_PPPOE_CONNECT:
 705                         /*
 706                          * Check the hook exists and is Uninitialised.
 707                          * Send a PADI request, and start the timeout logic.
 708                          * Store the originator of this message so we can send
 709                          * a success of fail message to them later.
 710                          * Move the session to SINIT
 711                          * Set up the session to the correct state and
 712                          * start it.
 713                          */
 714                         neg->service.hdr.tag_type = PTT_SRV_NAME;
 715                         neg->service.hdr.tag_len =
 716                                         htons((u_int16_t)ourmsg->data_len);
 717                         if (ourmsg->data_len) {
 718                                 bcopy(ourmsg->data,
 719                                         neg->service.data, ourmsg->data_len);
 720                         }
 721                         neg->service_len = ourmsg->data_len;
 722                         pppoe_start(sp);
 723                         break;
 724                 case NGM_PPPOE_LISTEN:
 725                         /*
 726                          * Check the hook exists and is Uninitialised.
 727                          * Install the service matching string.
 728                          * Store the originator of this message so we can send
 729                          * a success of fail message to them later.
 730                          * Move the hook to 'LISTENING'
 731                          */
 732                         neg->service.hdr.tag_type = PTT_SRV_NAME;
 733                         neg->service.hdr.tag_len =
 734                                         htons((u_int16_t)ourmsg->data_len);
 735
 736                         if (ourmsg->data_len) {
 737                                 bcopy(ourmsg->data,
 738                                         neg->service.data, ourmsg->data_len);
 739                         }
 740                         neg->service_len = ourmsg->data_len;
 741                         neg->pkt->pkt_header.ph.code = PADT_CODE;
 742                         /*
 743                          * wait for PADI packet coming from ethernet
 744                          */
 745                         sp->state = PPPOE_LISTENING;
 746                         break;
 747                 case NGM_PPPOE_OFFER:
 748                         /*
 749                          * Check the hook exists and is Uninitialised.
 750                          * Store the originator of this message so we can send
 751                          * a success of fail message to them later.
 752                          * Store the AC-Name given and go to PRIMED.
 753                          */
 754                         neg->ac_name.hdr.tag_type = PTT_AC_NAME;
 755                         neg->ac_name.hdr.tag_len =
 756                                         htons((u_int16_t)ourmsg->data_len);
 757                         if (ourmsg->data_len) {
 758                                 bcopy(ourmsg->data,
 759                                         neg->ac_name.data, ourmsg->data_len);
 760                         }
 761                         neg->ac_name_len = ourmsg->data_len;
 762                         neg->pkt->pkt_header.ph.code = PADO_CODE;
 763                         /*
 764                          * Wait for PADI packet coming from hook
 765                          */
 766                         sp->state = PPPOE_PRIMED;
 767                         break;
 768                 case NGM_PPPOE_SERVICE:
 769                         /*
 770                          * Check the session is primed.
 771                          * for now just allow ONE service to be advertised.
 772                          * If you do it twice you just overwrite.
 773                          */
 774                         if (sp->state != PPPOE_PRIMED) {
 775                                 printf("pppoe: Session not primed\n");
 776                                 LEAVE(EISCONN);
 777                         }
 778                         neg = sp->neg;
 779                         neg->service.hdr.tag_type = PTT_SRV_NAME;
 780                         neg->service.hdr.tag_len =
 781                             htons((u_int16_t)ourmsg->data_len);
 782
 783                         if (ourmsg->data_len)
 784                                 bcopy(ourmsg->data, neg->service.data,
 785                                     ourmsg->data_len);
 786                         neg->service_len = ourmsg->data_len;
 787                         break;
 788                 default:
 789                         LEAVE(EINVAL);
 790                 }
 791                 break;
 792         default:
 793                 LEAVE(EINVAL);
 794         }
 795
 796         /* Take care of synchronous response, if any */
 797         if (rptr)
 798                 *rptr = resp;
 799         else if (resp)
 800                 FREE(resp, M_NETGRAPH);
 801
 802         /* Free the message and return */
 803 quit:
 804         FREE(msg, M_NETGRAPH);
 805         return(error);
 806 }
 807
 808 /*
 809  * Start a client into the first state. A separate function because
 810  * it can be needed if the negotiation times out.
 811  */
 812 static void
 813 pppoe_start(sessp sp)
 814 {
 815         struct {
 816                 struct pppoe_tag hdr;
 817                 union   uniq    data;
 818         } __attribute ((packed)) uniqtag;
 819
 820         /*
 821          * kick the state machine into starting up
 822          */
 823 AAA
 824         sp->state = PPPOE_SINIT;
 825         /* reset the packet header to broadcast */
 826         sp->neg->pkt->pkt_header.eh = eh_prototype;
 827         sp->neg->pkt->pkt_header.ph.code = PADI_CODE;
 828         uniqtag.hdr.tag_type = PTT_HOST_UNIQ;
 829         uniqtag.hdr.tag_len = htons((u_int16_t)sizeof(uniqtag.data));
 830         uniqtag.data.pointer = sp;
 831         init_tags(sp);
 832         insert_tag(sp, &uniqtag.hdr);
 833         insert_tag(sp, &sp->neg->service.hdr);
 834         make_packet(sp);
 835         sendpacket(sp);
 836 }
 837
 838 static int
 839 send_acname(sessp sp, const struct pppoe_tag *tag)
 840 {
 841         int error, tlen;
 842         struct ng_mesg *msg;
 843         struct ngpppoe_sts *sts;
 844
 845         NG_MKMESSAGE(msg, NGM_PPPOE_COOKIE, NGM_PPPOE_ACNAME,
 846             sizeof(struct ngpppoe_sts), M_NOWAIT);
 847         if (msg == NULL)
 848                 return (ENOMEM);
 849
 850         sts = (struct ngpppoe_sts *)msg->data;
 851         tlen = min(NG_HOOKLEN, ntohs(tag->tag_len));
 852         strncpy(sts->hook, tag->tag_data, tlen);
 853         sts->hook[tlen] = '\0';
 854         error = ng_send_msg(sp->hook->node, msg, sp->creator, NULL);
 855
 856         return (error);
 857 }
 858
 859 static int
 860 send_sessionid(sessp sp)
 861 {
 862         int error;
 863         struct ng_mesg *msg;
 864
 865         NG_MKMESSAGE(msg, NGM_PPPOE_COOKIE, NGM_PPPOE_SESSIONID,
 866             sizeof(u_int16_t), M_NOWAIT);
 867         if (msg == NULL)
 868                 return (ENOMEM);
 869
 870         *(u_int16_t *)msg->data = sp->Session_ID;
 871         error = ng_send_msg(sp->hook->node, msg, sp->creator, NULL);
 872
 873         return (error);
 874 }
 875
 876 /*
 877  * Receive data, and do something with it.
 878  * The caller will never free m or meta, so
 879  * if we use up this data or abort we must free BOTH of these.
 880  */
 881 static int
 882 ng_pppoe_rcvdata(hook_p hook, struct mbuf *m, meta_p meta)
 883 {
 884         node_p                  node = hook->node;
 885         const priv_p            privp = node->private;
 886         sessp                   sp = hook->private;
 887         const struct pppoe_full_hdr *wh;
 888         const struct pppoe_hdr  *ph;
 889         int                     error = 0;
 890         u_int16_t               session;
 891         u_int16_t               length;
 892         u_int8_t                code;
 893         const struct pppoe_tag  *utag = NULL, *tag = NULL;
 894         hook_p                  sendhook;
 895         struct {
 896                 struct pppoe_tag hdr;
 897                 union   uniq    data;
 898         } __attribute ((packed)) uniqtag;
 899         negp                    neg = NULL;
 900
 901 AAA
 902         if (hook->private == &privp->debug_hook) {
 903                 /*
 904                  * Data from the debug hook gets sent without modification
 905                  * straight to the ethernet.
 906                  */
 907                 NG_SEND_DATA( error, privp->ethernet_hook, m, meta);
 908                 privp->packets_out++;
 909         } else if (hook->private == &privp->ethernet_hook) {
 910                 /*
 911                  * Incoming data.
 912                  * Dig out various fields from the packet.
 913                  * use them to decide where to send it.
 914                  */
 915
 916                 privp->packets_in++;
 917                 if( m->m_len < sizeof(*wh)) {
 918                         m = m_pullup(m, sizeof(*wh)); /* Checks length */
 919                         if (m == NULL) {
 920                                 printf("couldn't m_pullup\n");
 921                                 LEAVE(ENOBUFS);
 922                         }
 923                 }
 924                 wh = mtod(m, struct pppoe_full_hdr *);
 925                 ph = &wh->ph;
 926                 session = ntohs(wh->ph.sid);
 927                 length = ntohs(wh->ph.length);
 928                 code = wh->ph.code;
 929                 switch(wh->eh.ether_type) {
 930                 case    ETHERTYPE_PPPOE_STUPID_DISC:
 931                         if (pppoe_mode == PPPOE_STANDARD) {
 932                                 pppoe_mode = PPPOE_NONSTANDARD;
 933                                 eh_prototype.ether_type =
 934                                     ETHERTYPE_PPPOE_STUPID_DISC;
 935                                 log(LOG_NOTICE,
 936                                     "Switched to nonstandard PPPoE mode due to "
 937                                     "packet from %*D\n",
 938                                     ETHER_ADDR_LEN,
 939                                     wh->eh.ether_shost, ":");
 940                         } else if (pppoe_mode == PPPOE_KEEPSTANDARD)
 941                                 log(LOG_NOTICE,
 942                                     "Ignored nonstandard PPPoE packet "
 943                                     "from %*D\n",
 944                                     ETHER_ADDR_LEN,
 945                                     wh->eh.ether_shost, ":");
 946                         /* fall through */
 947                 case    ETHERTYPE_PPPOE_DISC:
 948                         /*
 949                          * We need to try to make sure that the tag area
 950                          * is contiguous, or we could wander off the end
 951                          * of a buffer and make a mess.
 952                          * (Linux wouldn't have this problem).
 953                          */
 954 /*XXX fix this mess */
 955
 956                         if (m->m_pkthdr.len <= MHLEN) {
 957                                 if( m->m_len < m->m_pkthdr.len) {
 958                                         m = m_pullup(m, m->m_pkthdr.len);
 959                                         if (m == NULL) {
 960                                                 printf("couldn't m_pullup\n");
 961                                                 LEAVE(ENOBUFS);
 962                                         }
 963                                 }
 964                         }
 965                         if (m->m_len != m->m_pkthdr.len) {
 966                                 /*
 967                                  * It's not all in one piece.
 968                                  * We need to do extra work.
 969                                  */
 970                                 printf("packet fragmented\n");
 971                                 LEAVE(EMSGSIZE);
 972                         }
 973
 974                         switch(code) {
 975                         case    PADI_CODE:
 976                                 /*
 977                                  * We are a server:
 978                                  * Look for a hook with the required service
 979                                  * and send the ENTIRE packet up there.
 980                                  * It should come back to a new hook in
 981                                  * PRIMED state. Look there for further
 982                                  * processing.
 983                                  */
 984                                 tag = get_tag(ph, PTT_SRV_NAME);
 985                                 if (tag == NULL) {
 986                                         printf("no service tag\n");
 987                                         LEAVE(ENETUNREACH);
 988                                 }
 989                                 sendhook = pppoe_match_svc(hook->node,
 990                                         tag->tag_data, ntohs(tag->tag_len),
 991                                         NG_MATCH_ANY);
 992                                 if (sendhook) {
 993                                         NG_SEND_DATA(error, sendhook, m, meta);
 994                                 } else {
 995                                         LEAVE(ENETUNREACH);
 996                                 }
 997                                 break;
 998                         case    PADO_CODE:
 999                                 /*
1000                                  * We are a client:
1001                                  * Use the host_uniq tag to find the
1002                                  * hook this is in response to.
1003                                  * Received #2, now send #3
1004                                  * For now simply accept the first we receive.
1005                                  */
1006                                 utag = get_tag(ph, PTT_HOST_UNIQ);
1007                                 if ((utag == NULL)
1008                                 || (ntohs(utag->tag_len) != sizeof(sp))) {
1009                                         printf("no host unique field\n");
1010                                         LEAVE(ENETUNREACH);
1011                                 }
1012
1013                                 sendhook = pppoe_finduniq(node, utag);
1014                                 if (sendhook == NULL) {
1015                                         printf("no matching session\n");
1016                                         LEAVE(ENETUNREACH);
1017                                 }
1018
1019                                 /*
1020                                  * Check the session is in the right state.
1021                                  * It needs to be in PPPOE_SINIT.
1022                                  */
1023                                 sp = sendhook->private;
1024                                 if (sp->state != PPPOE_SINIT) {
1025                                         printf("session in wrong state\n");
1026                                         LEAVE(ENETUNREACH);
1027                                 }
1028                                 neg = sp->neg;
1029                                 untimeout(pppoe_ticker, sendhook,
1030                                     neg->timeout_handle);
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                                 untimeout(pppoe_ticker, sendhook,
1097                                     neg->timeout_handle);
1098                                 neg->pkt->pkt_header.ph.code = PADS_CODE;
1099                                 if (sp->Session_ID == 0)
1100                                         neg->pkt->pkt_header.ph.sid =
1101                                             htons(sp->Session_ID
1102                                                 = get_new_sid(node));
1103                                 send_sessionid(sp);
1104                                 neg->timeout = 0;
1105                                 /*
1106                                  * start working out the tags to respond with.
1107                                  */
1108                                 init_tags(sp);
1109                                 insert_tag(sp, &neg->ac_name.hdr); /* AC_NAME */
1110                                 if ((tag = get_tag(ph, PTT_SRV_NAME)))
1111                                         insert_tag(sp, tag);/* return service */
1112                                 if ((tag = get_tag(ph, PTT_HOST_UNIQ)))
1113                                         insert_tag(sp, tag); /* return it */
1114                                 insert_tag(sp, utag);   /* ac_cookie */
1115                                 scan_tags(sp, ph);
1116                                 make_packet(sp);
1117                                 sp->state = PPPOE_NEWCONNECTED;
1118                                 sendpacket(sp);
1119                                 /*
1120                                  * Having sent the last Negotiation header,
1121                                  * Set up the stored packet header to
1122                                  * be correct for the actual session.
1123                                  * But keep the negotialtion stuff
1124                                  * around in case we need to resend this last
1125                                  * packet. We'll discard it when we move
1126                                  * from NEWCONNECTED to CONNECTED
1127                                  */
1128                                 sp->pkt_hdr = neg->pkt->pkt_header;
1129                                 if (pppoe_mode == PPPOE_NONSTANDARD)
1130                                         sp->pkt_hdr.eh.ether_type
1131                                                 = ETHERTYPE_PPPOE_STUPID_SESS;
1132                                 else
1133                                         sp->pkt_hdr.eh.ether_type
1134                                                 = ETHERTYPE_PPPOE_SESS;
1135                                 sp->pkt_hdr.ph.code = 0;
1136                                 pppoe_send_event(sp, NGM_PPPOE_SUCCESS);
1137                                 break;
1138                         case    PADS_CODE:
1139                                 /*
1140                                  * We are a client:
1141                                  * Use the host_uniq tag to find the
1142                                  * hook this is in response to.
1143                                  * take the session ID and store it away.
1144                                  * Also make sure the pre-made header is
1145                                  * correct and set us into Session mode.
1146                                  */
1147                                 utag = get_tag(ph, PTT_HOST_UNIQ);
1148                                 if ((utag == NULL)
1149                                 || (ntohs(utag->tag_len) != sizeof(sp))) {
1150                                         LEAVE (ENETUNREACH);
1151                                         break;
1152                                 }
1153                                 sendhook = pppoe_finduniq(node, utag);
1154                                 if (sendhook == NULL) {
1155                                         LEAVE(ENETUNREACH);
1156                                 }
1157
1158                                 /*
1159                                  * Check the session is in the right state.
1160                                  * It needs to be in PPPOE_SREQ.
1161                                  */
1162                                 sp = sendhook->private;
1163                                 if (sp->state != PPPOE_SREQ) {
1164                                         LEAVE(ENETUNREACH);
1165                                 }
1166                                 neg = sp->neg;
1167                                 untimeout(pppoe_ticker, sendhook,
1168                                     neg->timeout_handle);
1169                                 neg->pkt->pkt_header.ph.sid = wh->ph.sid;
1170                                 sp->Session_ID = ntohs(wh->ph.sid);
1171                                 send_sessionid(sp);
1172                                 neg->timeout = 0;
1173                                 sp->state = PPPOE_CONNECTED;
1174                                 /*
1175                                  * Now we have gone to Connected mode,
1176                                  * Free all resources needed for
1177                                  * negotiation.
1178                                  * Keep a copy of the header we will be using.
1179                                  */
1180                                 sp->pkt_hdr = neg->pkt->pkt_header;
1181                                 if (pppoe_mode == PPPOE_NONSTANDARD)
1182                                         sp->pkt_hdr.eh.ether_type
1183                                                 = ETHERTYPE_PPPOE_STUPID_SESS;
1184                                 else
1185                                         sp->pkt_hdr.eh.ether_type
1186                                                 = ETHERTYPE_PPPOE_SESS;
1187                                 sp->pkt_hdr.ph.code = 0;
1188                                 m_freem(neg->m);
1189                                 FREE(sp->neg, M_NETGRAPH);
1190                                 sp->neg = NULL;
1191                                 pppoe_send_event(sp, NGM_PPPOE_SUCCESS);
1192                                 break;
1193                         case    PADT_CODE:
1194                                 /*
1195                                  * Send a 'close' message to the controlling
1196                                  * process (the one that set us up);
1197                                  * And then tear everything down.
1198                                  *
1199                                  * Find matching peer/session combination.
1200                                  */
1201                                 sendhook = pppoe_findsession(node, wh);
1202                                 NG_FREE_DATA(m, meta); /* no longer needed */
1203                                 if (sendhook == NULL) {
1204                                         LEAVE(ENETUNREACH);
1205                                 }
1206                                 /* send message to creator */
1207                                 /* close hook */
1208                                 if (sendhook) {
1209                                         ng_destroy_hook(sendhook);
1210                                 }
1211                                 break;
1212                         default:
1213                                 LEAVE(EPFNOSUPPORT);
1214                         }
1215                         break;
1216                 case    ETHERTYPE_PPPOE_STUPID_SESS:
1217                 case    ETHERTYPE_PPPOE_SESS:
1218                         /*
1219                          * find matching peer/session combination.
1220                          */
1221                         sendhook = pppoe_findsession(node, wh);
1222                         if (sendhook == NULL) {
1223                                 LEAVE (ENETUNREACH);
1224                                 break;
1225                         }
1226                         sp = sendhook->private;
1227                         m_adj(m, sizeof(*wh));
1228                         if (m->m_pkthdr.len < length) {
1229                                 /* Packet too short, dump it */
1230                                 LEAVE(EMSGSIZE);
1231                         }
1232
1233                         /* Also need to trim excess at the end */
1234                         if (m->m_pkthdr.len > length) {
1235                                 m_adj(m, -((int)(m->m_pkthdr.len - length)));
1236                         }
1237                         if ( sp->state != PPPOE_CONNECTED) {
1238                                 if (sp->state == PPPOE_NEWCONNECTED) {
1239                                         sp->state = PPPOE_CONNECTED;
1240                                         /*
1241                                          * Now we have gone to Connected mode,
1242                                          * Free all resources needed for
1243                                          * negotiation. Be paranoid about
1244                                          * whether there may be a timeout.
1245                                          */
1246                                         m_freem(sp->neg->m);
1247                                         untimeout(pppoe_ticker, sendhook,
1248                                                 sp->neg->timeout_handle);
1249                                         FREE(sp->neg, M_NETGRAPH);
1250                                         sp->neg = NULL;
1251                                 } else {
1252                                         LEAVE (ENETUNREACH);
1253                                         break;
1254                                 }
1255                         }
1256                         NG_SEND_DATA( error, sendhook, m, meta);
1257                         break;
1258                 default:
1259                         LEAVE(EPFNOSUPPORT);
1260                 }
1261         } else {
1262                 /*
1263                  *      Not ethernet or debug hook..
1264                  *
1265                  * The packet has come in on a normal hook.
1266                  * We need to find out what kind of hook,
1267                  * So we can decide how to handle it.
1268                  * Check the hook's state.
1269                  */
1270                 sp = hook->private;
1271                 switch (sp->state) {
1272                 case    PPPOE_NEWCONNECTED:
1273                 case    PPPOE_CONNECTED: {
1274                         static const u_char addrctrl[] = { 0xff, 0x03 };
1275                         struct pppoe_full_hdr *wh;
1276
1277                         /*
1278                          * Remove PPP address and control fields, if any.
1279                          * For example, ng_ppp(4) always sends LCP packets
1280                          * with address and control fields as required by
1281                          * generic PPP. PPPoE is an exception to the rule.
1282                          */
1283                         if (m->m_pkthdr.len >= 2) {
1284                                 if (m->m_len < 2 && !(m = m_pullup(m, 2)))
1285                                         LEAVE(ENOBUFS);
1286                                 if (bcmp(mtod(m, u_char *), addrctrl, 2) == 0)
1287                                         m_adj(m, 2);
1288                         }
1289                         /*
1290                          * Bang in a pre-made header, and set the length up
1291                          * to be correct. Then send it to the ethernet driver.
1292                          * But first correct the length.
1293                          */
1294                         sp->pkt_hdr.ph.length = htons((short)(m->m_pkthdr.len));
1295                         M_PREPEND(m, sizeof(*wh), MB_DONTWAIT);
1296                         if (m == NULL) {
1297                                 LEAVE(ENOBUFS);
1298                         }
1299                         wh = mtod(m, struct pppoe_full_hdr *);
1300                         bcopy(&sp->pkt_hdr, wh, sizeof(*wh));
1301                         NG_SEND_DATA( error, privp->ethernet_hook, m, meta);
1302                         privp->packets_out++;
1303                         break;
1304                         }
1305                 case    PPPOE_PRIMED:
1306                         /*
1307                          * A PADI packet is being returned by the application
1308                          * that has set up this hook. This indicates that it
1309                          * wants us to offer service.
1310                          */
1311                         neg = sp->neg;
1312                         if (m->m_len < sizeof(*wh)) {
1313                                 m = m_pullup(m, sizeof(*wh));
1314                                 if (m == NULL) {
1315                                         LEAVE(ENOBUFS);
1316                                 }
1317                         }
1318                         wh = mtod(m, struct pppoe_full_hdr *);
1319                         ph = &wh->ph;
1320                         session = ntohs(wh->ph.sid);
1321                         length = ntohs(wh->ph.length);
1322                         code = wh->ph.code;
1323                         if ( code != PADI_CODE) {
1324                                 LEAVE(EINVAL);
1325                         };
1326                         untimeout(pppoe_ticker, hook,
1327                                     neg->timeout_handle);
1328
1329                         /*
1330                          * This is the first time we hear
1331                          * from the client, so note it's
1332                          * unicast address, replacing the
1333                          * broadcast address.
1334                          */
1335                         bcopy(wh->eh.ether_shost,
1336                                 neg->pkt->pkt_header.eh.ether_dhost,
1337                                 ETHER_ADDR_LEN);
1338                         sp->state = PPPOE_SOFFER;
1339                         neg->timeout = 0;
1340                         neg->pkt->pkt_header.ph.code = PADO_CODE;
1341
1342                         /*
1343                          * start working out the tags to respond with.
1344                          */
1345                         uniqtag.hdr.tag_type = PTT_AC_COOKIE;
1346                         uniqtag.hdr.tag_len = htons((u_int16_t)sizeof(sp));
1347                         uniqtag.data.pointer = sp;
1348                         init_tags(sp);
1349                         insert_tag(sp, &neg->ac_name.hdr); /* AC_NAME */
1350                         if ((tag = get_tag(ph, PTT_SRV_NAME)))
1351                                 insert_tag(sp, tag);      /* return service */
1352                         /*
1353                          * If we have a NULL service request
1354                          * and have an extra service defined in this hook,
1355                          * then also add a tag for the extra service.
1356                          * XXX this is a hack. eventually we should be able
1357                          * to support advertising many services, not just one
1358                          */
1359                         if (((tag == NULL) || (tag->tag_len == 0))
1360                         && (neg->service.hdr.tag_len != 0)) {
1361                                 insert_tag(sp, &neg->service.hdr); /* SERVICE */
1362                         }
1363                         if ((tag = get_tag(ph, PTT_HOST_UNIQ)))
1364                                 insert_tag(sp, tag); /* returned hostunique */
1365                         insert_tag(sp, &uniqtag.hdr);
1366                         scan_tags(sp, ph);
1367                         make_packet(sp);
1368                         sendpacket(sp);
1369                         break;
1370
1371                 /*
1372                  * Packets coming from the hook make no sense
1373                  * to sessions in these states. Throw them away.
1374                  */
1375                 case    PPPOE_SINIT:
1376                 case    PPPOE_SREQ:
1377                 case    PPPOE_SOFFER:
1378                 case    PPPOE_SNONE:
1379                 case    PPPOE_LISTENING:
1380                 case    PPPOE_DEAD:
1381                 default:
1382                         LEAVE(ENETUNREACH);
1383                 }
1384         }
1385 quit:
1386         NG_FREE_DATA(m, meta);
1387         return error;
1388 }
1389
1390 /*
1391  * Do local shutdown processing..
1392  * If we are a persistant device, we might refuse to go away, and
1393  * we'd only remove our links and reset ourself.
1394  */
1395 static int
1396 ng_pppoe_rmnode(node_p node)
1397 {
1398         const priv_p privdata = node->private;
1399
1400 AAA
1401         node->flags |= NG_INVALID;
1402         ng_cutlinks(node);
1403         ng_unname(node);
1404         node->private = NULL;
1405         ng_unref(privdata->node);
1406         FREE(privdata, M_NETGRAPH);
1407         return (0);
1408 }
1409
1410 /*
1411  * This is called once we've already connected a new hook to the other node.
1412  * It gives us a chance to balk at the last minute.
1413  */
1414 static int
1415 ng_pppoe_connect(hook_p hook)
1416 {
1417         /* be really amiable and just say "YUP that's OK by me! " */
1418         return (0);
1419 }
1420
1421 /*
1422  * Hook disconnection
1423  *
1424  * Clean up all dangling links and information about the session/hook.
1425  * For this type, removal of the last link destroys the node
1426  */
1427 static int
1428 ng_pppoe_disconnect(hook_p hook)
1429 {
1430         node_p node = hook->node;
1431         priv_p privp = node->private;
1432         sessp   sp;
1433         int     hooks;
1434
1435 AAA
1436         hooks = node->numhooks; /* this one already not counted */
1437         if (hook->private == &privp->debug_hook) {
1438                 privp->debug_hook = NULL;
1439         } else if (hook->private == &privp->ethernet_hook) {
1440                 privp->ethernet_hook = NULL;
1441                 ng_rmnode(node);
1442         } else {
1443                 sp = hook->private;
1444                 if (sp->state != PPPOE_SNONE ) {
1445                         pppoe_send_event(sp, NGM_PPPOE_CLOSE);
1446                 }
1447                 /*
1448                  * According to the spec, if we are connected,
1449                  * we should send a DISC packet if we are shutting down
1450                  * a session.
1451                  */
1452                 if ((privp->ethernet_hook)
1453                 && ((sp->state == PPPOE_CONNECTED)
1454                  || (sp->state == PPPOE_NEWCONNECTED))) {
1455                         struct mbuf *m;
1456                         struct pppoe_full_hdr *wh;
1457                         struct pppoe_tag *tag;
1458                         int     msglen = strlen(SIGNOFF);
1459                         void *dummy = NULL;
1460                         int error = 0;
1461
1462                         /* revert the stored header to DISC/PADT mode */
1463                         wh = &sp->pkt_hdr;
1464                         wh->ph.code = PADT_CODE;
1465                         if (pppoe_mode == PPPOE_NONSTANDARD)
1466                                 wh->eh.ether_type = ETHERTYPE_PPPOE_STUPID_DISC;
1467                         else
1468                                 wh->eh.ether_type = ETHERTYPE_PPPOE_DISC;
1469
1470                         /* generate a packet of that type */
1471                         MGETHDR(m, MB_DONTWAIT, MT_DATA);
1472                         if(m == NULL)
1473                                 printf("pppoe: Session out of mbufs\n");
1474                         else {
1475                                 m->m_pkthdr.rcvif = NULL;
1476                                 m->m_pkthdr.len = m->m_len = sizeof(*wh);
1477                                 bcopy((caddr_t)wh, mtod(m, caddr_t),
1478                                     sizeof(*wh));
1479                                 /*
1480                                  * Add a General error message and adjust
1481                                  * sizes
1482                                  */
1483                                 wh = mtod(m, struct pppoe_full_hdr *);
1484                                 tag = wh->ph.tag;
1485                                 tag->tag_type = PTT_GEN_ERR;
1486                                 tag->tag_len = htons((u_int16_t)msglen);
1487                                 strncpy(tag->tag_data, SIGNOFF, msglen);
1488                                 m->m_pkthdr.len = (m->m_len += sizeof(*tag) +
1489                                     msglen);
1490                                 wh->ph.length = htons(sizeof(*tag) + msglen);
1491                                 NG_SEND_DATA(error, privp->ethernet_hook, m,
1492                                     dummy);
1493                         }
1494                 }
1495                 /*
1496                  * As long as we have somewhere to store the timeout handle,
1497                  * we may have a timeout pending.. get rid of it.
1498                  */
1499                 if (sp->neg) {
1500                         untimeout(pppoe_ticker, hook, sp->neg->timeout_handle);
1501                         if (sp->neg->m)
1502                                 m_freem(sp->neg->m);
1503                         FREE(sp->neg, M_NETGRAPH);
1504                 }
1505                 FREE(sp, M_NETGRAPH);
1506                 hook->private = NULL;
1507                 /* work out how many session hooks there are */
1508                 /* Node goes away on last session hook removal */
1509                 if (privp->ethernet_hook) hooks -= 1;
1510                 if (privp->debug_hook) hooks -= 1;
1511         }
1512         if (node->numhooks == 0)
1513                 ng_rmnode(node);
1514         return (0);
1515 }
1516
1517 /*
1518  * timeouts come here.
1519  */
1520 static void
1521 pppoe_ticker(void *arg)
1522 {
1523         int s = splnet();
1524         hook_p hook = arg;
1525         sessp   sp = hook->private;
1526         negp    neg = sp->neg;
1527         int     error = 0;
1528         struct mbuf *m0 = NULL;
1529         priv_p privp = hook->node->private;
1530         meta_p dummy = NULL;
1531
1532 AAA
1533         switch(sp->state) {
1534                 /*
1535                  * resend the last packet, using an exponential backoff.
1536                  * After a period of time, stop growing the backoff,
1537                  * and either leave it, or revert to the start.
1538                  */
1539         case    PPPOE_SINIT:
1540         case    PPPOE_SREQ:
1541                 /* timeouts on these produce resends */
1542                 m0 = m_copypacket(sp->neg->m, MB_DONTWAIT);
1543                 NG_SEND_DATA( error, privp->ethernet_hook, m0, dummy);
1544                 neg->timeout_handle = timeout(pppoe_ticker,
1545                                         hook, neg->timeout * hz);
1546                 if ((neg->timeout <<= 1) > PPPOE_TIMEOUT_LIMIT) {
1547                         if (sp->state == PPPOE_SREQ) {
1548                                 /* revert to SINIT mode */
1549                                 pppoe_start(sp);
1550                         } else {
1551                                 neg->timeout = PPPOE_TIMEOUT_LIMIT;
1552                         }
1553                 }
1554                 break;
1555         case    PPPOE_PRIMED:
1556         case    PPPOE_SOFFER:
1557                 /* a timeout on these says "give up" */
1558                 ng_destroy_hook(hook);
1559                 break;
1560         default:
1561                 /* timeouts have no meaning in other states */
1562                 printf("pppoe: unexpected timeout\n");
1563         }
1564         splx(s);
1565 }
1566
1567
1568 static void
1569 sendpacket(sessp sp)
1570 {
1571         int     error = 0;
1572         struct mbuf *m0 = NULL;
1573         hook_p hook = sp->hook;
1574         negp    neg = sp->neg;
1575         priv_p  privp = hook->node->private;
1576         meta_p dummy = NULL;
1577
1578 AAA
1579         switch(sp->state) {
1580         case    PPPOE_LISTENING:
1581         case    PPPOE_DEAD:
1582         case    PPPOE_SNONE:
1583         case    PPPOE_CONNECTED:
1584                 printf("pppoe: sendpacket: unexpected state\n");
1585                 break;
1586
1587         case    PPPOE_NEWCONNECTED:
1588                 /* send the PADS without a timeout - we're now connected */
1589                 m0 = m_copypacket(sp->neg->m, MB_DONTWAIT);
1590                 NG_SEND_DATA( error, privp->ethernet_hook, m0, dummy);
1591                 break;
1592
1593         case    PPPOE_PRIMED:
1594                 /* No packet to send, but set up the timeout */
1595                 neg->timeout_handle = timeout(pppoe_ticker,
1596                                         hook, PPPOE_OFFER_TIMEOUT * hz);
1597                 break;
1598
1599         case    PPPOE_SOFFER:
1600                 /*
1601                  * send the offer but if they don't respond
1602                  * in PPPOE_OFFER_TIMEOUT seconds, forget about it.
1603                  */
1604                 m0 = m_copypacket(sp->neg->m, MB_DONTWAIT);
1605                 NG_SEND_DATA( error, privp->ethernet_hook, m0, dummy);
1606                 neg->timeout_handle = timeout(pppoe_ticker,
1607                                         hook, PPPOE_OFFER_TIMEOUT * hz);
1608                 break;
1609
1610         case    PPPOE_SINIT:
1611         case    PPPOE_SREQ:
1612                 m0 = m_copypacket(sp->neg->m, MB_DONTWAIT);
1613                 NG_SEND_DATA( error, privp->ethernet_hook, m0, dummy);
1614                 neg->timeout_handle = timeout(pppoe_ticker, hook,
1615                                         (hz * PPPOE_INITIAL_TIMEOUT));
1616                 neg->timeout = PPPOE_INITIAL_TIMEOUT * 2;
1617                 break;
1618
1619         default:
1620                 error = EINVAL;
1621                 printf("pppoe: timeout: bad state\n");
1622         }
1623         /* return (error); */
1624 }
1625
1626 /*
1627  * Parse an incoming packet to see if any tags should be copied to the
1628  * output packet. Don't do any tags that have been handled in the main
1629  * state machine.
1630  */
1631 static const struct pppoe_tag*
1632 scan_tags(sessp sp, const struct pppoe_hdr* ph)
1633 {
1634         const char *const end = (const char *)next_tag(ph);
1635         const char *ptn;
1636         const struct pppoe_tag *pt = &ph->tag[0];
1637         /*
1638          * Keep processing tags while a tag header will still fit.
1639          */
1640 AAA
1641         while((const char*)(pt + 1) <= end) {
1642                 /*
1643                  * If the tag data would go past the end of the packet, abort.
1644                  */
1645                 ptn = (((const char *)(pt + 1)) + ntohs(pt->tag_len));
1646                 if(ptn > end)
1647                         return NULL;
1648
1649                 switch (pt->tag_type) {
1650                 case    PTT_RELAY_SID:
1651                         insert_tag(sp, pt);
1652                         break;
1653                 case    PTT_EOL:
1654                         return NULL;
1655                 case    PTT_SRV_NAME:
1656                 case    PTT_AC_NAME:
1657                 case    PTT_HOST_UNIQ:
1658                 case    PTT_AC_COOKIE:
1659                 case    PTT_VENDOR:
1660                 case    PTT_SRV_ERR:
1661                 case    PTT_SYS_ERR:
1662                 case    PTT_GEN_ERR:
1663                         break;
1664                 }
1665                 pt = (const struct pppoe_tag*)ptn;
1666         }
1667         return NULL;
1668 }
1669
1670 static  int
1671 pppoe_send_event(sessp sp, enum cmd cmdid)
1672 {
1673         int error;
1674         struct ng_mesg *msg;
1675         struct ngpppoe_sts *sts;
1676
1677 AAA
1678         NG_MKMESSAGE(msg, NGM_PPPOE_COOKIE, cmdid,
1679                         sizeof(struct ngpppoe_sts), M_NOWAIT);
1680         if (msg == NULL)
1681                 return (ENOMEM);
1682         sts = (struct ngpppoe_sts *)msg->data;
1683         strncpy(sts->hook, sp->hook->name, NG_HOOKLEN + 1);
1684         error = ng_send_msg(sp->hook->node, msg, sp->creator, NULL);
1685         return (error);
1686 }