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 1.11 2008/01/05 14:02:39 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 kprintf("pppoe: %s\n", __func__ );
  45 #define BBB kprintf("-%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_NODESIZ]; /* 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                 kprintf("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                 kprintf("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                 kprintf("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                 kprintf("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                         kprintf("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 | M_ZERO);
 518         if (privdata == NULL)
 519                 return (ENOMEM);
 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 | M_ZERO);
 562                 if (sp == NULL)
 563                         return (ENOMEM);
 564
 565                 hook->private = sp;
 566                 sp->hook = hook;
 567         }
 568         return(0);
 569 }
 570
 571 /*
 572  * Get a netgraph control message.
 573  * Check it is one we understand. If needed, send a response.
 574  * We sometimes save the address for an async action later.
 575  * Always free the message.
 576  */
 577 static int
 578 ng_pppoe_rcvmsg(node_p node,
 579            struct ng_mesg *msg, const char *retaddr, struct ng_mesg **rptr)
 580 {
 581         priv_p privp = node->private;
 582         struct ngpppoe_init_data *ourmsg = NULL;
 583         struct ng_mesg *resp = NULL;
 584         int error = 0;
 585         hook_p hook = NULL;
 586         sessp sp = NULL;
 587         negp neg = NULL;
 588
 589 AAA
 590         /* Deal with message according to cookie and command */
 591         switch (msg->header.typecookie) {
 592         case NGM_PPPOE_COOKIE:
 593                 switch (msg->header.cmd) {
 594                 case NGM_PPPOE_CONNECT:
 595                 case NGM_PPPOE_LISTEN:
 596                 case NGM_PPPOE_OFFER:
 597                 case NGM_PPPOE_SERVICE:
 598                         ourmsg = (struct ngpppoe_init_data *)msg->data;
 599                         if (( sizeof(*ourmsg) > msg->header.arglen)
 600                         || ((sizeof(*ourmsg) + ourmsg->data_len)
 601                             > msg->header.arglen)) {
 602                                 kprintf("pppoe_rcvmsg: bad arg size");
 603                                 LEAVE(EMSGSIZE);
 604                         }
 605                         if (ourmsg->data_len > PPPOE_SERVICE_NAME_SIZE) {
 606                                 kprintf("pppoe: init data too long (%d)\n",
 607                                                         ourmsg->data_len);
 608                                 LEAVE(EMSGSIZE);
 609                         }
 610                         /* make sure strcmp will terminate safely */
 611                         ourmsg->hook[sizeof(ourmsg->hook) - 1] = '\0';
 612
 613                         /* cycle through all known hooks */
 614                         LIST_FOREACH(hook, &node->hooks, hooks) {
 615                                 if (hook->name
 616                                 && strcmp(hook->name, ourmsg->hook) == 0)
 617                                         break;
 618                         }
 619                         if (hook == NULL) {
 620                                 LEAVE(ENOENT);
 621                         }
 622                         if ((hook->private == &privp->debug_hook)
 623                         ||  (hook->private == &privp->ethernet_hook)) {
 624                                 LEAVE(EINVAL);
 625                         }
 626                         sp = hook->private;
 627
 628                         if (msg->header.cmd == NGM_PPPOE_LISTEN) {
 629                                 /*
 630                                  * Ensure we aren't already listening for this
 631                                  * service.
 632                                  */
 633                                 if (pppoe_match_svc(node, ourmsg->data,
 634                                     ourmsg->data_len, NG_MATCH_EXACT) != NULL) {
 635                                         LEAVE(EEXIST);
 636                                 }
 637                         }
 638
 639                         /*
 640                          * PPPOE_SERVICE advertisments are set up
 641                          * on sessions that are in PRIMED state.
 642                          */
 643                         if (msg->header.cmd == NGM_PPPOE_SERVICE) {
 644                                 break;
 645                         }
 646                         if (sp->state |= PPPOE_SNONE) {
 647                                 kprintf("pppoe: Session already active\n");
 648                                 LEAVE(EISCONN);
 649                         }
 650
 651                         /*
 652                          * set up prototype header
 653                          */
 654                         MALLOC(neg, negp, sizeof(*neg), M_NETGRAPH,
 655                             M_NOWAIT | M_ZERO);
 656
 657                         if (neg == NULL) {
 658                                 kprintf("pppoe: Session out of memory\n");
 659                                 LEAVE(ENOMEM);
 660                         }
 661                         MGETHDR(neg->m, MB_DONTWAIT, MT_DATA);
 662                         if(neg->m == NULL) {
 663                                 kprintf("pppoe: Session out of mbufs\n");
 664                                 FREE(neg, M_NETGRAPH);
 665                                 LEAVE(ENOBUFS);
 666                         }
 667                         neg->m->m_pkthdr.rcvif = NULL;
 668                         MCLGET(neg->m, MB_DONTWAIT);
 669                         if ((neg->m->m_flags & M_EXT) == 0) {
 670                                 kprintf("pppoe: Session out of mcls\n");
 671                                 m_freem(neg->m);
 672                                 FREE(neg, M_NETGRAPH);
 673                                 LEAVE(ENOBUFS);
 674                         }
 675                         sp->neg = neg;
 676                         callout_init(&neg->timeout_ch);
 677                         neg->m->m_len = sizeof(struct pppoe_full_hdr);
 678                         neg->pkt = mtod(neg->m, union packet*);
 679                         neg->pkt->pkt_header.eh = eh_prototype;
 680                         neg->pkt->pkt_header.ph.ver = 0x1;
 681                         neg->pkt->pkt_header.ph.type = 0x1;
 682                         neg->pkt->pkt_header.ph.sid = 0x0000;
 683                         neg->timeout = 0;
 684
 685                         strlcpy(sp->creator, retaddr, NG_NODESIZ);
 686                 }
 687                 switch (msg->header.cmd) {
 688                 case NGM_PPPOE_GET_STATUS:
 689                     {
 690                         struct ngpppoestat *stats;
 691
 692                         NG_MKRESPONSE(resp, msg, sizeof(*stats), M_NOWAIT);
 693                         if (!resp) {
 694                                 LEAVE(ENOMEM);
 695                         }
 696                         stats = (struct ngpppoestat *) resp->data;
 697                         stats->packets_in = privp->packets_in;
 698                         stats->packets_out = privp->packets_out;
 699                         break;
 700                     }
 701                 case NGM_PPPOE_CONNECT:
 702                         /*
 703                          * Check the hook exists and is Uninitialised.
 704                          * Send a PADI request, and start the timeout logic.
 705                          * Store the originator of this message so we can send
 706                          * a success of fail message to them later.
 707                          * Move the session to SINIT
 708                          * Set up the session to the correct state and
 709                          * start it.
 710                          */
 711                         neg->service.hdr.tag_type = PTT_SRV_NAME;
 712                         neg->service.hdr.tag_len =
 713                                         htons((u_int16_t)ourmsg->data_len);
 714                         if (ourmsg->data_len) {
 715                                 bcopy(ourmsg->data,
 716                                         neg->service.data, ourmsg->data_len);
 717                         }
 718                         neg->service_len = ourmsg->data_len;
 719                         pppoe_start(sp);
 720                         break;
 721                 case NGM_PPPOE_LISTEN:
 722                         /*
 723                          * Check the hook exists and is Uninitialised.
 724                          * Install the service matching string.
 725                          * Store the originator of this message so we can send
 726                          * a success of fail message to them later.
 727                          * Move the hook to 'LISTENING'
 728                          */
 729                         neg->service.hdr.tag_type = PTT_SRV_NAME;
 730                         neg->service.hdr.tag_len =
 731                                         htons((u_int16_t)ourmsg->data_len);
 732
 733                         if (ourmsg->data_len) {
 734                                 bcopy(ourmsg->data,
 735                                         neg->service.data, ourmsg->data_len);
 736                         }
 737                         neg->service_len = ourmsg->data_len;
 738                         neg->pkt->pkt_header.ph.code = PADT_CODE;
 739                         /*
 740                          * wait for PADI packet coming from ethernet
 741                          */
 742                         sp->state = PPPOE_LISTENING;
 743                         break;
 744                 case NGM_PPPOE_OFFER:
 745                         /*
 746                          * Check the hook exists and is Uninitialised.
 747                          * Store the originator of this message so we can send
 748                          * a success of fail message to them later.
 749                          * Store the AC-Name given and go to PRIMED.
 750                          */
 751                         neg->ac_name.hdr.tag_type = PTT_AC_NAME;
 752                         neg->ac_name.hdr.tag_len =
 753                                         htons((u_int16_t)ourmsg->data_len);
 754                         if (ourmsg->data_len) {
 755                                 bcopy(ourmsg->data,
 756                                         neg->ac_name.data, ourmsg->data_len);
 757                         }
 758                         neg->ac_name_len = ourmsg->data_len;
 759                         neg->pkt->pkt_header.ph.code = PADO_CODE;
 760                         /*
 761                          * Wait for PADI packet coming from hook
 762                          */
 763                         sp->state = PPPOE_PRIMED;
 764                         break;
 765                 case NGM_PPPOE_SERVICE:
 766                         /*
 767                          * Check the session is primed.
 768                          * for now just allow ONE service to be advertised.
 769                          * If you do it twice you just overwrite.
 770                          */
 771                         if (sp->state != PPPOE_PRIMED) {
 772                                 kprintf("pppoe: Session not primed\n");
 773                                 LEAVE(EISCONN);
 774                         }
 775                         neg = sp->neg;
 776                         neg->service.hdr.tag_type = PTT_SRV_NAME;
 777                         neg->service.hdr.tag_len =
 778                             htons((u_int16_t)ourmsg->data_len);
 779
 780                         if (ourmsg->data_len)
 781                                 bcopy(ourmsg->data, neg->service.data,
 782                                     ourmsg->data_len);
 783                         neg->service_len = ourmsg->data_len;
 784                         break;
 785                 default:
 786                         LEAVE(EINVAL);
 787                 }
 788                 break;
 789         default:
 790                 LEAVE(EINVAL);
 791         }
 792
 793         /* Take care of synchronous response, if any */
 794         if (rptr)
 795                 *rptr = resp;
 796         else if (resp)
 797                 FREE(resp, M_NETGRAPH);
 798
 799         /* Free the message and return */
 800 quit:
 801         FREE(msg, M_NETGRAPH);
 802         return(error);
 803 }
 804
 805 /*
 806  * Start a client into the first state. A separate function because
 807  * it can be needed if the negotiation times out.
 808  */
 809 static void
 810 pppoe_start(sessp sp)
 811 {
 812         struct {
 813                 struct pppoe_tag hdr;
 814                 union   uniq    data;
 815         } __attribute ((packed)) uniqtag;
 816
 817         /*
 818          * kick the state machine into starting up
 819          */
 820 AAA
 821         sp->state = PPPOE_SINIT;
 822         /* reset the packet header to broadcast */
 823         sp->neg->pkt->pkt_header.eh = eh_prototype;
 824         sp->neg->pkt->pkt_header.ph.code = PADI_CODE;
 825         uniqtag.hdr.tag_type = PTT_HOST_UNIQ;
 826         uniqtag.hdr.tag_len = htons((u_int16_t)sizeof(uniqtag.data));
 827         uniqtag.data.pointer = sp;
 828         init_tags(sp);
 829         insert_tag(sp, &uniqtag.hdr);
 830         insert_tag(sp, &sp->neg->service.hdr);
 831         make_packet(sp);
 832         sendpacket(sp);
 833 }
 834
 835 static int
 836 send_acname(sessp sp, const struct pppoe_tag *tag)
 837 {
 838         int error, tlen;
 839         struct ng_mesg *msg;
 840         struct ngpppoe_sts *sts;
 841
 842         NG_MKMESSAGE(msg, NGM_PPPOE_COOKIE, NGM_PPPOE_ACNAME,
 843             sizeof(struct ngpppoe_sts), M_NOWAIT);
 844         if (msg == NULL)
 845                 return (ENOMEM);
 846
 847         sts = (struct ngpppoe_sts *)msg->data;
 848         tlen = min(NG_HOOKSIZ - 1, ntohs(tag->tag_len));
 849         strncpy(sts->hook, tag->tag_data, tlen);
 850         sts->hook[tlen] = '\0';
 851         error = ng_send_msg(sp->hook->node, msg, sp->creator, NULL);
 852
 853         return (error);
 854 }
 855
 856 static int
 857 send_sessionid(sessp sp)
 858 {
 859         int error;
 860         struct ng_mesg *msg;
 861
 862         NG_MKMESSAGE(msg, NGM_PPPOE_COOKIE, NGM_PPPOE_SESSIONID,
 863             sizeof(u_int16_t), M_NOWAIT);
 864         if (msg == NULL)
 865                 return (ENOMEM);
 866
 867         *(u_int16_t *)msg->data = sp->Session_ID;
 868         error = ng_send_msg(sp->hook->node, msg, sp->creator, NULL);
 869
 870         return (error);
 871 }
 872
 873 /*
 874  * Receive data, and do something with it.
 875  * The caller will never free m or meta, so
 876  * if we use up this data or abort we must free BOTH of these.
 877  */
 878 static int
 879 ng_pppoe_rcvdata(hook_p hook, struct mbuf *m, meta_p meta)
 880 {
 881         node_p                  node = hook->node;
 882         const priv_p            privp = node->private;
 883         sessp                   sp = hook->private;
 884         const struct pppoe_full_hdr *wh;
 885         const struct pppoe_hdr  *ph;
 886         int                     error = 0;
 887         u_int16_t               session;
 888         u_int16_t               length;
 889         u_int8_t                code;
 890         const struct pppoe_tag  *utag = NULL, *tag = NULL;
 891         hook_p                  sendhook;
 892         struct {
 893                 struct pppoe_tag hdr;
 894                 union   uniq    data;
 895         } __attribute ((packed)) uniqtag;
 896         negp                    neg = NULL;
 897
 898 AAA
 899         if (hook->private == &privp->debug_hook) {
 900                 /*
 901                  * Data from the debug hook gets sent without modification
 902                  * straight to the ethernet.
 903                  */
 904                 NG_SEND_DATA( error, privp->ethernet_hook, m, meta);
 905                 privp->packets_out++;
 906         } else if (hook->private == &privp->ethernet_hook) {
 907                 /*
 908                  * Incoming data.
 909                  * Dig out various fields from the packet.
 910                  * use them to decide where to send it.
 911                  */
 912
 913                 privp->packets_in++;
 914                 if( m->m_len < sizeof(*wh)) {
 915                         m = m_pullup(m, sizeof(*wh)); /* Checks length */
 916                         if (m == NULL) {
 917                                 kprintf("couldn't m_pullup\n");
 918                                 LEAVE(ENOBUFS);
 919                         }
 920                 }
 921                 wh = mtod(m, struct pppoe_full_hdr *);
 922                 ph = &wh->ph;
 923                 session = ntohs(wh->ph.sid);
 924                 length = ntohs(wh->ph.length);
 925                 code = wh->ph.code;
 926                 switch(wh->eh.ether_type) {
 927                 case    ETHERTYPE_PPPOE_STUPID_DISC:
 928                         if (pppoe_mode == PPPOE_STANDARD) {
 929                                 pppoe_mode = PPPOE_NONSTANDARD;
 930                                 eh_prototype.ether_type =
 931                                     ETHERTYPE_PPPOE_STUPID_DISC;
 932                                 log(LOG_NOTICE,
 933                                     "Switched to nonstandard PPPoE mode due to "
 934                                     "packet from %*D\n",
 935                                     ETHER_ADDR_LEN,
 936                                     wh->eh.ether_shost, ":");
 937                         } else if (pppoe_mode == PPPOE_KEEPSTANDARD)
 938                                 log(LOG_NOTICE,
 939                                     "Ignored nonstandard PPPoE packet "
 940                                     "from %*D\n",
 941                                     ETHER_ADDR_LEN,
 942                                     wh->eh.ether_shost, ":");
 943                         /* fall through */
 944                 case    ETHERTYPE_PPPOE_DISC:
 945                         /*
 946                          * We need to try to make sure that the tag area
 947                          * is contiguous, or we could wander off the end
 948                          * of a buffer and make a mess.
 949                          * (Linux wouldn't have this problem).
 950                          */
 951 /*XXX fix this mess */
 952
 953                         if (m->m_pkthdr.len <= MHLEN) {
 954                                 if( m->m_len < m->m_pkthdr.len) {
 955                                         m = m_pullup(m, m->m_pkthdr.len);
 956                                         if (m == NULL) {
 957                                                 kprintf("couldn't m_pullup\n");
 958                                                 LEAVE(ENOBUFS);
 959                                         }
 960                                 }
 961                         }
 962                         if (m->m_len != m->m_pkthdr.len) {
 963                                 /*
 964                                  * It's not all in one piece.
 965                                  * We need to do extra work.
 966                                  */
 967                                 kprintf("packet fragmented\n");
 968                                 LEAVE(EMSGSIZE);
 969                         }
 970
 971                         switch(code) {
 972                         case    PADI_CODE:
 973                                 /*
 974                                  * We are a server:
 975                                  * Look for a hook with the required service
 976                                  * and send the ENTIRE packet up there.
 977                                  * It should come back to a new hook in
 978                                  * PRIMED state. Look there for further
 979                                  * processing.
 980                                  */
 981                                 tag = get_tag(ph, PTT_SRV_NAME);
 982                                 if (tag == NULL) {
 983                                         kprintf("no service tag\n");
 984                                         LEAVE(ENETUNREACH);
 985                                 }
 986                                 sendhook = pppoe_match_svc(hook->node,
 987                                         tag->tag_data, ntohs(tag->tag_len),
 988                                         NG_MATCH_ANY);
 989                                 if (sendhook) {
 990                                         NG_SEND_DATA(error, sendhook, m, meta);
 991                                 } else {
 992                                         LEAVE(ENETUNREACH);
 993                                 }
 994                                 break;
 995                         case    PADO_CODE:
 996                                 /*
 997                                  * We are a client:
 998                                  * Use the host_uniq tag to find the
 999                                  * hook this is in response to.
1000                                  * Received #2, now send #3
1001                                  * For now simply accept the first we receive.
1002                                  */
1003                                 utag = get_tag(ph, PTT_HOST_UNIQ);
1004                                 if ((utag == NULL)
1005                                 || (ntohs(utag->tag_len) != sizeof(sp))) {
1006                                         kprintf("no host unique field\n");
1007                                         LEAVE(ENETUNREACH);
1008                                 }
1009
1010                                 sendhook = pppoe_finduniq(node, utag);
1011                                 if (sendhook == NULL) {
1012                                         kprintf("no matching session\n");
1013                                         LEAVE(ENETUNREACH);
1014                                 }
1015
1016                                 /*
1017                                  * Check the session is in the right state.
1018                                  * It needs to be in PPPOE_SINIT.
1019                                  */
1020                                 sp = sendhook->private;
1021                                 if (sp->state != PPPOE_SINIT) {
1022                                         kprintf("session in wrong state\n");
1023                                         LEAVE(ENETUNREACH);
1024                                 }
1025                                 neg = sp->neg;
1026                                 callout_stop(&neg->timeout_ch);
1027
1028                                 /*
1029                                  * This is the first time we hear
1030                                  * from the server, so note it's
1031                                  * unicast address, replacing the
1032                                  * broadcast address .
1033                                  */
1034                                 bcopy(wh->eh.ether_shost,
1035                                         neg->pkt->pkt_header.eh.ether_dhost,
1036                                         ETHER_ADDR_LEN);
1037                                 neg->timeout = 0;
1038                                 neg->pkt->pkt_header.ph.code = PADR_CODE;
1039                                 init_tags(sp);
1040                                 insert_tag(sp, utag);      /* Host Unique */
1041                                 if ((tag = get_tag(ph, PTT_AC_COOKIE)))
1042                                         insert_tag(sp, tag); /* return cookie */
1043                                 if ((tag = get_tag(ph, PTT_AC_NAME))) {
1044                                         insert_tag(sp, tag); /* return it */
1045                                         send_acname(sp, tag);
1046                                 }
1047                                 insert_tag(sp, &neg->service.hdr); /* Service */
1048                                 scan_tags(sp, ph);
1049                                 make_packet(sp);
1050                                 sp->state = PPPOE_SREQ;
1051                                 sendpacket(sp);
1052                                 break;
1053                         case    PADR_CODE:
1054
1055                                 /*
1056                                  * We are a server:
1057                                  * Use the ac_cookie tag to find the
1058                                  * hook this is in response to.
1059                                  */
1060                                 utag = get_tag(ph, PTT_AC_COOKIE);
1061                                 if ((utag == NULL)
1062                                 || (ntohs(utag->tag_len) != sizeof(sp))) {
1063                                         LEAVE(ENETUNREACH);
1064                                 }
1065
1066                                 sendhook = pppoe_finduniq(node, utag);
1067                                 if (sendhook == NULL) {
1068                                         LEAVE(ENETUNREACH);
1069                                 }
1070
1071                                 /*
1072                                  * Check the session is in the right state.
1073                                  * It needs to be in PPPOE_SOFFER
1074                                  * or PPPOE_NEWCONNECTED. If the latter,
1075                                  * then this is a retry by the client.
1076                                  * so be nice, and resend.
1077                                  */
1078                                 sp = sendhook->private;
1079                                 if (sp->state == PPPOE_NEWCONNECTED) {
1080                                         /*
1081                                          * Whoa! drop back to resend that
1082                                          * PADS packet.
1083                                          * We should still have a copy of it.
1084                                          */
1085                                         sp->state = PPPOE_SOFFER;
1086                                 }
1087                                 if (sp->state != PPPOE_SOFFER) {
1088                                         LEAVE (ENETUNREACH);
1089                                         break;
1090                                 }
1091                                 neg = sp->neg;
1092                                 callout_stop(&neg->timeout_ch);
1093                                 neg->pkt->pkt_header.ph.code = PADS_CODE;
1094                                 if (sp->Session_ID == 0)
1095                                         neg->pkt->pkt_header.ph.sid =
1096                                             htons(sp->Session_ID
1097                                                 = get_new_sid(node));
1098                                 send_sessionid(sp);
1099                                 neg->timeout = 0;
1100                                 /*
1101                                  * start working out the tags to respond with.
1102                                  */
1103                                 init_tags(sp);
1104                                 insert_tag(sp, &neg->ac_name.hdr); /* AC_NAME */
1105                                 if ((tag = get_tag(ph, PTT_SRV_NAME)))
1106                                         insert_tag(sp, tag);/* return service */
1107                                 if ((tag = get_tag(ph, PTT_HOST_UNIQ)))
1108                                         insert_tag(sp, tag); /* return it */
1109                                 insert_tag(sp, utag);   /* ac_cookie */
1110                                 scan_tags(sp, ph);
1111                                 make_packet(sp);
1112                                 sp->state = PPPOE_NEWCONNECTED;
1113                                 sendpacket(sp);
1114                                 /*
1115                                  * Having sent the last Negotiation header,
1116                                  * Set up the stored packet header to
1117                                  * be correct for the actual session.
1118                                  * But keep the negotialtion stuff
1119                                  * around in case we need to resend this last
1120                                  * packet. We'll discard it when we move
1121                                  * from NEWCONNECTED to CONNECTED
1122                                  */
1123                                 sp->pkt_hdr = neg->pkt->pkt_header;
1124                                 if (pppoe_mode == PPPOE_NONSTANDARD)
1125                                         sp->pkt_hdr.eh.ether_type
1126                                                 = ETHERTYPE_PPPOE_STUPID_SESS;
1127                                 else
1128                                         sp->pkt_hdr.eh.ether_type
1129                                                 = ETHERTYPE_PPPOE_SESS;
1130                                 sp->pkt_hdr.ph.code = 0;
1131                                 pppoe_send_event(sp, NGM_PPPOE_SUCCESS);
1132                                 break;
1133                         case    PADS_CODE:
1134                                 /*
1135                                  * We are a client:
1136                                  * Use the host_uniq tag to find the
1137                                  * hook this is in response to.
1138                                  * take the session ID and store it away.
1139                                  * Also make sure the pre-made header is
1140                                  * correct and set us into Session mode.
1141                                  */
1142                                 utag = get_tag(ph, PTT_HOST_UNIQ);
1143                                 if ((utag == NULL)
1144                                 || (ntohs(utag->tag_len) != sizeof(sp))) {
1145                                         LEAVE (ENETUNREACH);
1146                                         break;
1147                                 }
1148                                 sendhook = pppoe_finduniq(node, utag);
1149                                 if (sendhook == NULL) {
1150                                         LEAVE(ENETUNREACH);
1151                                 }
1152
1153                                 /*
1154                                  * Check the session is in the right state.
1155                                  * It needs to be in PPPOE_SREQ.
1156                                  */
1157                                 sp = sendhook->private;
1158                                 if (sp->state != PPPOE_SREQ) {
1159                                         LEAVE(ENETUNREACH);
1160                                 }
1161                                 neg = sp->neg;
1162                                 callout_stop(&neg->timeout_ch);
1163                                 neg->pkt->pkt_header.ph.sid = wh->ph.sid;
1164                                 sp->Session_ID = ntohs(wh->ph.sid);
1165                                 send_sessionid(sp);
1166                                 neg->timeout = 0;
1167                                 sp->state = PPPOE_CONNECTED;
1168                                 /*
1169                                  * Now we have gone to Connected mode,
1170                                  * Free all resources needed for
1171                                  * negotiation.
1172                                  * Keep a copy of the header we will be using.
1173                                  */
1174                                 sp->pkt_hdr = neg->pkt->pkt_header;
1175                                 if (pppoe_mode == PPPOE_NONSTANDARD)
1176                                         sp->pkt_hdr.eh.ether_type
1177                                                 = ETHERTYPE_PPPOE_STUPID_SESS;
1178                                 else
1179                                         sp->pkt_hdr.eh.ether_type
1180                                                 = ETHERTYPE_PPPOE_SESS;
1181                                 sp->pkt_hdr.ph.code = 0;
1182                                 m_freem(neg->m);
1183                                 FREE(sp->neg, M_NETGRAPH);
1184                                 sp->neg = NULL;
1185                                 pppoe_send_event(sp, NGM_PPPOE_SUCCESS);
1186                                 break;
1187                         case    PADT_CODE:
1188                                 /*
1189                                  * Send a 'close' message to the controlling
1190                                  * process (the one that set us up);
1191                                  * And then tear everything down.
1192                                  *
1193                                  * Find matching peer/session combination.
1194                                  */
1195                                 sendhook = pppoe_findsession(node, wh);
1196                                 NG_FREE_DATA(m, meta); /* no longer needed */
1197                                 if (sendhook == NULL) {
1198                                         LEAVE(ENETUNREACH);
1199                                 }
1200                                 /* send message to creator */
1201                                 /* close hook */
1202                                 if (sendhook) {
1203                                         ng_destroy_hook(sendhook);
1204                                 }
1205                                 break;
1206                         default:
1207                                 LEAVE(EPFNOSUPPORT);
1208                         }
1209                         break;
1210                 case    ETHERTYPE_PPPOE_STUPID_SESS:
1211                 case    ETHERTYPE_PPPOE_SESS:
1212                         /*
1213                          * find matching peer/session combination.
1214                          */
1215                         sendhook = pppoe_findsession(node, wh);
1216                         if (sendhook == NULL) {
1217                                 LEAVE (ENETUNREACH);
1218                                 break;
1219                         }
1220                         sp = sendhook->private;
1221                         m_adj(m, sizeof(*wh));
1222                         if (m->m_pkthdr.len < length) {
1223                                 /* Packet too short, dump it */
1224                                 LEAVE(EMSGSIZE);
1225                         }
1226
1227                         /* Also need to trim excess at the end */
1228                         if (m->m_pkthdr.len > length) {
1229                                 m_adj(m, -((int)(m->m_pkthdr.len - length)));
1230                         }
1231                         if ( sp->state != PPPOE_CONNECTED) {
1232                                 if (sp->state == PPPOE_NEWCONNECTED) {
1233                                         sp->state = PPPOE_CONNECTED;
1234                                         /*
1235                                          * Now we have gone to Connected mode,
1236                                          * Free all resources needed for
1237                                          * negotiation. Be paranoid about
1238                                          * whether there may be a timeout.
1239                                          */
1240                                         m_freem(sp->neg->m);
1241                                         callout_stop(&sp->neg->timeout_ch);
1242                                         FREE(sp->neg, M_NETGRAPH);
1243                                         sp->neg = NULL;
1244                                 } else {
1245                                         LEAVE (ENETUNREACH);
1246                                         break;
1247                                 }
1248                         }
1249                         NG_SEND_DATA( error, sendhook, m, meta);
1250                         break;
1251                 default:
1252                         LEAVE(EPFNOSUPPORT);
1253                 }
1254         } else {
1255                 /*
1256                  *      Not ethernet or debug hook..
1257                  *
1258                  * The packet has come in on a normal hook.
1259                  * We need to find out what kind of hook,
1260                  * So we can decide how to handle it.
1261                  * Check the hook's state.
1262                  */
1263                 sp = hook->private;
1264                 switch (sp->state) {
1265                 case    PPPOE_NEWCONNECTED:
1266                 case    PPPOE_CONNECTED: {
1267                         static const u_char addrctrl[] = { 0xff, 0x03 };
1268                         struct pppoe_full_hdr *wh;
1269
1270                         /*
1271                          * Remove PPP address and control fields, if any.
1272                          * For example, ng_ppp(4) always sends LCP packets
1273                          * with address and control fields as required by
1274                          * generic PPP. PPPoE is an exception to the rule.
1275                          */
1276                         if (m->m_pkthdr.len >= 2) {
1277                                 if (m->m_len < 2 && !(m = m_pullup(m, 2)))
1278                                         LEAVE(ENOBUFS);
1279                                 if (bcmp(mtod(m, u_char *), addrctrl, 2) == 0)
1280                                         m_adj(m, 2);
1281                         }
1282                         /*
1283                          * Bang in a pre-made header, and set the length up
1284                          * to be correct. Then send it to the ethernet driver.
1285                          * But first correct the length.
1286                          */
1287                         sp->pkt_hdr.ph.length = htons((short)(m->m_pkthdr.len));
1288                         M_PREPEND(m, sizeof(*wh), MB_DONTWAIT);
1289                         if (m == NULL) {
1290                                 LEAVE(ENOBUFS);
1291                         }
1292                         wh = mtod(m, struct pppoe_full_hdr *);
1293                         bcopy(&sp->pkt_hdr, wh, sizeof(*wh));
1294                         NG_SEND_DATA( error, privp->ethernet_hook, m, meta);
1295                         privp->packets_out++;
1296                         break;
1297                         }
1298                 case    PPPOE_PRIMED:
1299                         /*
1300                          * A PADI packet is being returned by the application
1301                          * that has set up this hook. This indicates that it
1302                          * wants us to offer service.
1303                          */
1304                         neg = sp->neg;
1305                         if (m->m_len < sizeof(*wh)) {
1306                                 m = m_pullup(m, sizeof(*wh));
1307                                 if (m == NULL) {
1308                                         LEAVE(ENOBUFS);
1309                                 }
1310                         }
1311                         wh = mtod(m, struct pppoe_full_hdr *);
1312                         ph = &wh->ph;
1313                         session = ntohs(wh->ph.sid);
1314                         length = ntohs(wh->ph.length);
1315                         code = wh->ph.code;
1316                         if ( code != PADI_CODE) {
1317                                 LEAVE(EINVAL);
1318                         };
1319                         callout_stop(&neg->timeout_ch);
1320
1321                         /*
1322                          * This is the first time we hear
1323                          * from the client, so note it's
1324                          * unicast address, replacing the
1325                          * broadcast address.
1326                          */
1327                         bcopy(wh->eh.ether_shost,
1328                                 neg->pkt->pkt_header.eh.ether_dhost,
1329                                 ETHER_ADDR_LEN);
1330                         sp->state = PPPOE_SOFFER;
1331                         neg->timeout = 0;
1332                         neg->pkt->pkt_header.ph.code = PADO_CODE;
1333
1334                         /*
1335                          * start working out the tags to respond with.
1336                          */
1337                         uniqtag.hdr.tag_type = PTT_AC_COOKIE;
1338                         uniqtag.hdr.tag_len = htons((u_int16_t)sizeof(sp));
1339                         uniqtag.data.pointer = sp;
1340                         init_tags(sp);
1341                         insert_tag(sp, &neg->ac_name.hdr); /* AC_NAME */
1342                         if ((tag = get_tag(ph, PTT_SRV_NAME)))
1343                                 insert_tag(sp, tag);      /* return service */
1344                         /*
1345                          * If we have a NULL service request
1346                          * and have an extra service defined in this hook,
1347                          * then also add a tag for the extra service.
1348                          * XXX this is a hack. eventually we should be able
1349                          * to support advertising many services, not just one
1350                          */
1351                         if (((tag == NULL) || (tag->tag_len == 0))
1352                         && (neg->service.hdr.tag_len != 0)) {
1353                                 insert_tag(sp, &neg->service.hdr); /* SERVICE */
1354                         }
1355                         if ((tag = get_tag(ph, PTT_HOST_UNIQ)))
1356                                 insert_tag(sp, tag); /* returned hostunique */
1357                         insert_tag(sp, &uniqtag.hdr);
1358                         scan_tags(sp, ph);
1359                         make_packet(sp);
1360                         sendpacket(sp);
1361                         break;
1362
1363                 /*
1364                  * Packets coming from the hook make no sense
1365                  * to sessions in these states. Throw them away.
1366                  */
1367                 case    PPPOE_SINIT:
1368                 case    PPPOE_SREQ:
1369                 case    PPPOE_SOFFER:
1370                 case    PPPOE_SNONE:
1371                 case    PPPOE_LISTENING:
1372                 case    PPPOE_DEAD:
1373                 default:
1374                         LEAVE(ENETUNREACH);
1375                 }
1376         }
1377 quit:
1378         NG_FREE_DATA(m, meta);
1379         return error;
1380 }
1381
1382 /*
1383  * Do local shutdown processing..
1384  * If we are a persistant device, we might refuse to go away, and
1385  * we'd only remove our links and reset ourself.
1386  */
1387 static int
1388 ng_pppoe_rmnode(node_p node)
1389 {
1390         const priv_p privdata = node->private;
1391
1392 AAA
1393         node->flags |= NG_INVALID;
1394         ng_cutlinks(node);
1395         ng_unname(node);
1396         node->private = NULL;
1397         ng_unref(privdata->node);
1398         FREE(privdata, M_NETGRAPH);
1399         return (0);
1400 }
1401
1402 /*
1403  * This is called once we've already connected a new hook to the other node.
1404  * It gives us a chance to balk at the last minute.
1405  */
1406 static int
1407 ng_pppoe_connect(hook_p hook)
1408 {
1409         /* be really amiable and just say "YUP that's OK by me! " */
1410         return (0);
1411 }
1412
1413 /*
1414  * Hook disconnection
1415  *
1416  * Clean up all dangling links and information about the session/hook.
1417  * For this type, removal of the last link destroys the node
1418  */
1419 static int
1420 ng_pppoe_disconnect(hook_p hook)
1421 {
1422         node_p node = hook->node;
1423         priv_p privp = node->private;
1424         sessp   sp;
1425         int     hooks;
1426
1427 AAA
1428         hooks = node->numhooks; /* this one already not counted */
1429         if (hook->private == &privp->debug_hook) {
1430                 privp->debug_hook = NULL;
1431         } else if (hook->private == &privp->ethernet_hook) {
1432                 privp->ethernet_hook = NULL;
1433                 ng_rmnode(node);
1434         } else {
1435                 sp = hook->private;
1436                 if (sp->state != PPPOE_SNONE ) {
1437                         pppoe_send_event(sp, NGM_PPPOE_CLOSE);
1438                 }
1439                 /*
1440                  * According to the spec, if we are connected,
1441                  * we should send a DISC packet if we are shutting down
1442                  * a session.
1443                  */
1444                 if ((privp->ethernet_hook)
1445                 && ((sp->state == PPPOE_CONNECTED)
1446                  || (sp->state == PPPOE_NEWCONNECTED))) {
1447                         struct mbuf *m;
1448                         struct pppoe_full_hdr *wh;
1449                         struct pppoe_tag *tag;
1450                         int     msglen = strlen(SIGNOFF);
1451                         void *dummy = NULL;
1452                         int error = 0;
1453
1454                         /* revert the stored header to DISC/PADT mode */
1455                         wh = &sp->pkt_hdr;
1456                         wh->ph.code = PADT_CODE;
1457                         if (pppoe_mode == PPPOE_NONSTANDARD)
1458                                 wh->eh.ether_type = ETHERTYPE_PPPOE_STUPID_DISC;
1459                         else
1460                                 wh->eh.ether_type = ETHERTYPE_PPPOE_DISC;
1461
1462                         /* generate a packet of that type */
1463                         MGETHDR(m, MB_DONTWAIT, MT_DATA);
1464                         if(m == NULL)
1465                                 kprintf("pppoe: Session out of mbufs\n");
1466                         else {
1467                                 m->m_pkthdr.rcvif = NULL;
1468                                 m->m_pkthdr.len = m->m_len = sizeof(*wh);
1469                                 bcopy((caddr_t)wh, mtod(m, caddr_t),
1470                                     sizeof(*wh));
1471                                 /*
1472                                  * Add a General error message and adjust
1473                                  * sizes
1474                                  */
1475                                 wh = mtod(m, struct pppoe_full_hdr *);
1476                                 tag = wh->ph.tag;
1477                                 tag->tag_type = PTT_GEN_ERR;
1478                                 tag->tag_len = htons((u_int16_t)msglen);
1479                                 strncpy(tag->tag_data, SIGNOFF, msglen);
1480                                 m->m_pkthdr.len = (m->m_len += sizeof(*tag) +
1481                                     msglen);
1482                                 wh->ph.length = htons(sizeof(*tag) + msglen);
1483                                 NG_SEND_DATA(error, privp->ethernet_hook, m,
1484                                     dummy);
1485                         }
1486                 }
1487                 /*
1488                  * As long as we have somewhere to store the timeout handle,
1489                  * we may have a timeout pending.. get rid of it.
1490                  */
1491                 if (sp->neg) {
1492                         callout_stop(&sp->neg->timeout_ch);
1493                         if (sp->neg->m)
1494                                 m_freem(sp->neg->m);
1495                         FREE(sp->neg, M_NETGRAPH);
1496                 }
1497                 FREE(sp, M_NETGRAPH);
1498                 hook->private = NULL;
1499                 /* work out how many session hooks there are */
1500                 /* Node goes away on last session hook removal */
1501                 if (privp->ethernet_hook) hooks -= 1;
1502                 if (privp->debug_hook) hooks -= 1;
1503         }
1504         if (node->numhooks == 0)
1505                 ng_rmnode(node);
1506         return (0);
1507 }
1508
1509 /*
1510  * timeouts come here.
1511  */
1512 static void
1513 pppoe_ticker(void *arg)
1514 {
1515         hook_p hook = arg;
1516         sessp   sp = hook->private;
1517         negp    neg = sp->neg;
1518         int     error = 0;
1519         struct mbuf *m0 = NULL;
1520         priv_p privp = hook->node->private;
1521         meta_p dummy = NULL;
1522
1523         crit_enter();
1524 AAA
1525         switch(sp->state) {
1526                 /*
1527                  * resend the last packet, using an exponential backoff.
1528                  * After a period of time, stop growing the backoff,
1529                  * and either leave it, or revert to the start.
1530                  */
1531         case    PPPOE_SINIT:
1532         case    PPPOE_SREQ:
1533                 /* timeouts on these produce resends */
1534                 m0 = m_copypacket(sp->neg->m, MB_DONTWAIT);
1535                 NG_SEND_DATA( error, privp->ethernet_hook, m0, dummy);
1536                 callout_reset(&neg->timeout_ch, neg->timeout * hz,
1537                                 pppoe_ticker, hook);
1538                 if ((neg->timeout <<= 1) > PPPOE_TIMEOUT_LIMIT) {
1539                         if (sp->state == PPPOE_SREQ) {
1540                                 /* revert to SINIT mode */
1541                                 pppoe_start(sp);
1542                         } else {
1543                                 neg->timeout = PPPOE_TIMEOUT_LIMIT;
1544                         }
1545                 }
1546                 break;
1547         case    PPPOE_PRIMED:
1548         case    PPPOE_SOFFER:
1549                 /* a timeout on these says "give up" */
1550                 ng_destroy_hook(hook);
1551                 break;
1552         default:
1553                 /* timeouts have no meaning in other states */
1554                 kprintf("pppoe: unexpected timeout\n");
1555         }
1556         crit_exit();
1557 }
1558
1559
1560 static void
1561 sendpacket(sessp sp)
1562 {
1563         int     error = 0;
1564         struct mbuf *m0 = NULL;
1565         hook_p hook = sp->hook;
1566         negp    neg = sp->neg;
1567         priv_p  privp = hook->node->private;
1568         meta_p dummy = NULL;
1569
1570 AAA
1571         switch(sp->state) {
1572         case    PPPOE_LISTENING:
1573         case    PPPOE_DEAD:
1574         case    PPPOE_SNONE:
1575         case    PPPOE_CONNECTED:
1576                 kprintf("pppoe: sendpacket: unexpected state\n");
1577                 break;
1578
1579         case    PPPOE_NEWCONNECTED:
1580                 /* send the PADS without a timeout - we're now connected */
1581                 m0 = m_copypacket(sp->neg->m, MB_DONTWAIT);
1582                 NG_SEND_DATA( error, privp->ethernet_hook, m0, dummy);
1583                 break;
1584
1585         case    PPPOE_PRIMED:
1586                 /* No packet to send, but set up the timeout */
1587                 callout_reset(&neg->timeout_ch, PPPOE_OFFER_TIMEOUT * hz,
1588                                 pppoe_ticker, hook);
1589                 break;
1590
1591         case    PPPOE_SOFFER:
1592                 /*
1593                  * send the offer but if they don't respond
1594                  * in PPPOE_OFFER_TIMEOUT seconds, forget about it.
1595                  */
1596                 m0 = m_copypacket(sp->neg->m, MB_DONTWAIT);
1597                 NG_SEND_DATA( error, privp->ethernet_hook, m0, dummy);
1598                 callout_reset(&neg->timeout_ch, PPPOE_OFFER_TIMEOUT * hz,
1599                                 pppoe_ticker, hook);
1600                 break;
1601
1602         case    PPPOE_SINIT:
1603         case    PPPOE_SREQ:
1604                 m0 = m_copypacket(sp->neg->m, MB_DONTWAIT);
1605                 NG_SEND_DATA( error, privp->ethernet_hook, m0, dummy);
1606                 callout_reset(&neg->timeout_ch, PPPOE_INITIAL_TIMEOUT * hz,
1607                                 pppoe_ticker, hook);
1608                 neg->timeout = PPPOE_INITIAL_TIMEOUT * 2;
1609                 break;
1610
1611         default:
1612                 error = EINVAL;
1613                 kprintf("pppoe: timeout: bad state\n");
1614         }
1615         /* return (error); */
1616 }
1617
1618 /*
1619  * Parse an incoming packet to see if any tags should be copied to the
1620  * output packet. Don't do any tags that have been handled in the main
1621  * state machine.
1622  */
1623 static const struct pppoe_tag*
1624 scan_tags(sessp sp, const struct pppoe_hdr* ph)
1625 {
1626         const char *const end = (const char *)next_tag(ph);
1627         const char *ptn;
1628         const struct pppoe_tag *pt = &ph->tag[0];
1629         /*
1630          * Keep processing tags while a tag header will still fit.
1631          */
1632 AAA
1633         while((const char*)(pt + 1) <= end) {
1634                 /*
1635                  * If the tag data would go past the end of the packet, abort.
1636                  */
1637                 ptn = (((const char *)(pt + 1)) + ntohs(pt->tag_len));
1638                 if(ptn > end)
1639                         return NULL;
1640
1641                 switch (pt->tag_type) {
1642                 case    PTT_RELAY_SID:
1643                         insert_tag(sp, pt);
1644                         break;
1645                 case    PTT_EOL:
1646                         return NULL;
1647                 case    PTT_SRV_NAME:
1648                 case    PTT_AC_NAME:
1649                 case    PTT_HOST_UNIQ:
1650                 case    PTT_AC_COOKIE:
1651                 case    PTT_VENDOR:
1652                 case    PTT_SRV_ERR:
1653                 case    PTT_SYS_ERR:
1654                 case    PTT_GEN_ERR:
1655                         break;
1656                 }
1657                 pt = (const struct pppoe_tag*)ptn;
1658         }
1659         return NULL;
1660 }
1661
1662 static  int
1663 pppoe_send_event(sessp sp, enum cmd cmdid)
1664 {
1665         int error;
1666         struct ng_mesg *msg;
1667         struct ngpppoe_sts *sts;
1668
1669 AAA
1670         NG_MKMESSAGE(msg, NGM_PPPOE_COOKIE, cmdid,
1671                         sizeof(struct ngpppoe_sts), M_NOWAIT);
1672         if (msg == NULL)
1673                 return (ENOMEM);
1674         sts = (struct ngpppoe_sts *)msg->data;
1675         strlcpy(sts->hook, sp->hook->name, NG_HOOKSIZ);
1676         error = ng_send_msg(sp->hook->node, msg, sp->creator, NULL);
1677         return (error);
1678 }