sys/netgraph/ng_pppoe.c

   1 /*
   2  * ng_pppoe.c
   3  */
   4
   5 /*-
   6  * Copyright (c) 1996-1999 Whistle Communications, Inc.
   7  * All rights reserved.
   8  *
   9  * Subject to the following obligations and disclaimer of warranty, use and
  10  * redistribution of this software, in source or object code forms, with or
  11  * without modifications are expressly permitted by Whistle Communications;
  12  * provided, however, that:
  13  * 1. Any and all reproductions of the source or object code must include the
  14  *    copyright notice above and the following disclaimer of warranties; and
  15  * 2. No rights are granted, in any manner or form, to use Whistle
  16  *    Communications, Inc. trademarks, including the mark "WHISTLE
  17  *    COMMUNICATIONS" on advertising, endorsements, or otherwise except as
  18  *    such appears in the above copyright notice or in the software.
  19  *
  20  * THIS SOFTWARE IS BEING PROVIDED BY WHISTLE COMMUNICATIONS "AS IS", AND
  21  * TO THE MAXIMUM EXTENT PERMITTED BY LAW, WHISTLE COMMUNICATIONS MAKES NO
  22  * REPRESENTATIONS OR WARRANTIES, EXPRESS OR IMPLIED, REGARDING THIS SOFTWARE,
  23  * INCLUDING WITHOUT LIMITATION, ANY AND ALL IMPLIED WARRANTIES OF
  24  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, OR NON-INFRINGEMENT.
  25  * WHISTLE COMMUNICATIONS DOES NOT WARRANT, GUARANTEE, OR MAKE ANY
  26  * REPRESENTATIONS REGARDING THE USE OF, OR THE RESULTS OF THE USE OF THIS
  27  * SOFTWARE IN TERMS OF ITS CORRECTNESS, ACCURACY, RELIABILITY OR OTHERWISE.
  28  * IN NO EVENT SHALL WHISTLE COMMUNICATIONS BE LIABLE FOR ANY DAMAGES
  29  * RESULTING FROM OR ARISING OUT OF ANY USE OF THIS SOFTWARE, INCLUDING
  30  * WITHOUT LIMITATION, ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY,
  31  * PUNITIVE, OR CONSEQUENTIAL DAMAGES, PROCUREMENT OF SUBSTITUTE GOODS OR
  32  * SERVICES, LOSS OF USE, DATA OR PROFITS, HOWEVER CAUSED AND UNDER ANY
  33  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  34  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  35  * THIS SOFTWARE, EVEN IF WHISTLE COMMUNICATIONS IS ADVISED OF THE POSSIBILITY
  36  * OF SUCH DAMAGE.
  37  *
  38  * Author: Julian Elischer <julian@freebsd.org>
  39  *
  40  * $FreeBSD$
  41  * $Whistle: ng_pppoe.c,v 1.10 1999/11/01 09:24:52 julian Exp $
  42  */
  43
  44 #include <sys/param.h>
  45 #include <sys/systm.h>
  46 #include <sys/kernel.h>
  47 #include <sys/ktr.h>
  48 #include <sys/mbuf.h>
  49 #include <sys/malloc.h>
  50 #include <sys/errno.h>
  51 #include <sys/epoch.h>
  52 #include <sys/syslog.h>
  53 #include <net/ethernet.h>
  54
  55 #include <netgraph/ng_message.h>
  56 #include <netgraph/netgraph.h>
  57 #include <netgraph/ng_parse.h>
  58 #include <netgraph/ng_pppoe.h>
  59 #include <netgraph/ng_ether.h>
  60
  61 #ifdef NG_SEPARATE_MALLOC
  62 static MALLOC_DEFINE(M_NETGRAPH_PPPOE, "netgraph_pppoe", "netgraph pppoe node");
  63 #else
  64 #define M_NETGRAPH_PPPOE M_NETGRAPH
  65 #endif
  66
  67 #define SIGNOFF "session closed"
  68
  69 /*
  70  * This section contains the netgraph method declarations for the
  71  * pppoe node. These methods define the netgraph pppoe 'type'.
  72  */
  73
  74 static ng_constructor_t ng_pppoe_constructor;
  75 static ng_rcvmsg_t      ng_pppoe_rcvmsg;
  76 static ng_shutdown_t    ng_pppoe_shutdown;
  77 static ng_newhook_t     ng_pppoe_newhook;
  78 static ng_connect_t     ng_pppoe_connect;
  79 static ng_rcvdata_t     ng_pppoe_rcvdata;
  80 static ng_rcvdata_t     ng_pppoe_rcvdata_ether;
  81 static ng_rcvdata_t     ng_pppoe_rcvdata_debug;
  82 static ng_disconnect_t  ng_pppoe_disconnect;
  83
  84 /* Parse type for struct ngpppoe_init_data */
  85 static const struct ng_parse_struct_field ngpppoe_init_data_type_fields[]
  86         = NG_PPPOE_INIT_DATA_TYPE_INFO;
  87 static const struct ng_parse_type ngpppoe_init_data_state_type = {
  88         &ng_parse_struct_type,
  89         &ngpppoe_init_data_type_fields
  90 };
  91
  92 /* Parse type for struct ngpppoe_sts */
  93 static const struct ng_parse_struct_field ng_pppoe_sts_type_fields[]
  94         = NG_PPPOE_STS_TYPE_INFO;
  95 static const struct ng_parse_type ng_pppoe_sts_state_type = {
  96         &ng_parse_struct_type,
  97         &ng_pppoe_sts_type_fields
  98 };
  99
 100 /* List of commands and how to convert arguments to/from ASCII */
 101 static const struct ng_cmdlist ng_pppoe_cmds[] = {
 102         {
 103           NGM_PPPOE_COOKIE,
 104           NGM_PPPOE_CONNECT,
 105           "pppoe_connect",
 106           &ngpppoe_init_data_state_type,
 107           NULL
 108         },
 109         {
 110           NGM_PPPOE_COOKIE,
 111           NGM_PPPOE_LISTEN,
 112           "pppoe_listen",
 113           &ngpppoe_init_data_state_type,
 114           NULL
 115         },
 116         {
 117           NGM_PPPOE_COOKIE,
 118           NGM_PPPOE_OFFER,
 119           "pppoe_offer",
 120           &ngpppoe_init_data_state_type,
 121           NULL
 122         },
 123         {
 124           NGM_PPPOE_COOKIE,
 125           NGM_PPPOE_SERVICE,
 126           "pppoe_service",
 127           &ngpppoe_init_data_state_type,
 128           NULL
 129         },
 130         {
 131           NGM_PPPOE_COOKIE,
 132           NGM_PPPOE_SUCCESS,
 133           "pppoe_success",
 134           &ng_pppoe_sts_state_type,
 135           NULL
 136         },
 137         {
 138           NGM_PPPOE_COOKIE,
 139           NGM_PPPOE_FAIL,
 140           "pppoe_fail",
 141           &ng_pppoe_sts_state_type,
 142           NULL
 143         },
 144         {
 145           NGM_PPPOE_COOKIE,
 146           NGM_PPPOE_CLOSE,
 147           "pppoe_close",
 148           &ng_pppoe_sts_state_type,
 149           NULL
 150         },
 151         {
 152           NGM_PPPOE_COOKIE,
 153           NGM_PPPOE_SETMODE,
 154           "pppoe_setmode",
 155           &ng_parse_string_type,
 156           NULL
 157         },
 158         {
 159           NGM_PPPOE_COOKIE,
 160           NGM_PPPOE_GETMODE,
 161           "pppoe_getmode",
 162           NULL,
 163           &ng_parse_string_type
 164         },
 165         {
 166           NGM_PPPOE_COOKIE,
 167           NGM_PPPOE_SETENADDR,
 168           "setenaddr",
 169           &ng_parse_enaddr_type,
 170           NULL
 171         },
 172         {
 173           NGM_PPPOE_COOKIE,
 174           NGM_PPPOE_SETMAXP,
 175           "setmaxp",
 176           &ng_parse_uint16_type,
 177           NULL
 178         },
 179         {
 180           NGM_PPPOE_COOKIE,
 181           NGM_PPPOE_SEND_HURL,
 182           "send_hurl",
 183           &ngpppoe_init_data_state_type,
 184           NULL
 185         },
 186         {
 187           NGM_PPPOE_COOKIE,
 188           NGM_PPPOE_SEND_MOTM,
 189           "send_motm",
 190           &ngpppoe_init_data_state_type,
 191           NULL
 192         },
 193         { 0 }
 194 };
 195
 196 /* Netgraph node type descriptor */
 197 static struct ng_type typestruct = {
 198         .version =      NG_ABI_VERSION,
 199         .name =         NG_PPPOE_NODE_TYPE,
 200         .constructor =  ng_pppoe_constructor,
 201         .rcvmsg =       ng_pppoe_rcvmsg,
 202         .shutdown =     ng_pppoe_shutdown,
 203         .newhook =      ng_pppoe_newhook,
 204         .connect =      ng_pppoe_connect,
 205         .rcvdata =      ng_pppoe_rcvdata,
 206         .disconnect =   ng_pppoe_disconnect,
 207         .cmdlist =      ng_pppoe_cmds,
 208 };
 209 NETGRAPH_INIT(pppoe, &typestruct);
 210
 211 /*
 212  * States for the session state machine.
 213  * These have no meaning if there is no hook attached yet.
 214  */
 215 enum state {
 216     PPPOE_SNONE=0,      /* [both] Initial state */
 217     PPPOE_LISTENING,    /* [Daemon] Listening for discover initiation pkt */
 218     PPPOE_SINIT,        /* [Client] Sent discovery initiation */
 219     PPPOE_PRIMED,       /* [Server] Awaiting PADI from daemon */
 220     PPPOE_SOFFER,       /* [Server] Sent offer message  (got PADI)*/
 221     PPPOE_SREQ,         /* [Client] Sent a Request */
 222     PPPOE_NEWCONNECTED, /* [Server] Connection established, No data received */
 223     PPPOE_CONNECTED,    /* [Both] Connection established, Data received */
 224     PPPOE_DEAD          /* [Both] */
 225 };
 226
 227 #define NUMTAGS 20 /* number of tags we are set up to work with */
 228
 229 /*
 230  * Information we store for each hook on each node for negotiating the
 231  * session. The mbuf and cluster are freed once negotiation has completed.
 232  * The whole negotiation block is then discarded.
 233  */
 234
 235 struct sess_neg {
 236         struct mbuf             *m; /* holds cluster with last sent packet */
 237         union   packet          *pkt; /* points within the above cluster */
 238         struct callout          handle;   /* see timeout(9) */
 239         u_int                   timeout; /* 0,1,2,4,8,16 etc. seconds */
 240         u_int                   numtags;
 241         const struct pppoe_tag  *tags[NUMTAGS];
 242         u_int                   service_len;
 243         u_int                   ac_name_len;
 244         u_int                   host_uniq_len;
 245
 246         struct datatag          service;
 247         struct datatag          ac_name;
 248         struct datatag          host_uniq;
 249 };
 250 typedef struct sess_neg *negp;
 251
 252 /*
 253  * Session information that is needed after connection.
 254  */
 255 struct sess_con {
 256         hook_p                  hook;
 257         uint16_t                Session_ID;
 258         enum state              state;
 259         ng_ID_t                 creator;        /* who to notify */
 260         struct pppoe_full_hdr   pkt_hdr;        /* used when connected */
 261         negp                    neg;            /* used when negotiating */
 262         LIST_ENTRY(sess_con)    sessions;
 263 };
 264 typedef struct sess_con *sessp;
 265
 266 #define SESSHASHSIZE    0x0100
 267 #define SESSHASH(x)     (((x) ^ ((x) >> 8)) & (SESSHASHSIZE - 1))
 268
 269 struct sess_hash_entry {
 270         struct mtx      mtx;
 271         LIST_HEAD(hhead, sess_con) head;
 272 };
 273
 274 /*
 275  * Information we store for each node
 276  */
 277 struct PPPoE {
 278         node_p          node;           /* back pointer to node */
 279         hook_p          ethernet_hook;
 280         hook_p          debug_hook;
 281         u_int           packets_in;     /* packets in from ethernet */
 282         u_int           packets_out;    /* packets out towards ethernet */
 283         uint32_t        flags;
 284 #define COMPAT_3COM     0x00000001
 285 #define COMPAT_DLINK    0x00000002
 286         struct ether_header     eh;
 287         LIST_HEAD(, sess_con) listeners;
 288         struct sess_hash_entry  sesshash[SESSHASHSIZE];
 289         struct maxptag  max_payload;    /* PPP-Max-Payload (RFC4638) */
 290 };
 291 typedef struct PPPoE *priv_p;
 292
 293 union uniq {
 294         char bytes[sizeof(void *)];
 295         void *pointer;
 296 };
 297
 298 #define LEAVE(x) do { error = x; goto quit; } while(0)
 299 static void     pppoe_start(sessp sp);
 300 static void     pppoe_ticker(node_p node, hook_p hook, void *arg1, int arg2);
 301 static const    struct pppoe_tag *scan_tags(sessp sp,
 302                         const struct pppoe_hdr* ph);
 303 static  int     pppoe_send_event(sessp sp, enum cmd cmdid);
 304
 305 /*************************************************************************
 306  * Some basic utilities  from the Linux version with author's permission.*
 307  * Author:      Michal Ostrowski <mostrows@styx.uwaterloo.ca>            *
 308  ************************************************************************/
 309
 310 /*
 311  * Return the location where the next tag can be put
 312  */
 313 static __inline const struct pppoe_tag*
 314 next_tag(const struct pppoe_hdr* ph)
 315 {
 316         return (const struct pppoe_tag*)(((const char*)(ph + 1))
 317             + ntohs(ph->length));
 318 }
 319
 320 /*
 321  * Look for a tag of a specific type.
 322  * Don't trust any length the other end says,
 323  * but assume we already sanity checked ph->length.
 324  */
 325 static const struct pppoe_tag*
 326 get_tag(const struct pppoe_hdr* ph, uint16_t idx)
 327 {
 328         const char *const end = (const char *)next_tag(ph);
 329         const struct pppoe_tag *pt = (const void *)(ph + 1);
 330         const char *ptn;
 331
 332         /*
 333          * Keep processing tags while a tag header will still fit.
 334          */
 335         while((const char*)(pt + 1) <= end) {
 336                 /*
 337                  * If the tag data would go past the end of the packet, abort.
 338                  */
 339                 ptn = (((const char *)(pt + 1)) + ntohs(pt->tag_len));
 340                 if (ptn > end) {
 341                         CTR2(KTR_NET, "%20s: invalid length for tag %d",
 342                             __func__, idx);
 343                         return (NULL);
 344                 }
 345                 if (pt->tag_type == idx) {
 346                         CTR2(KTR_NET, "%20s: found tag %d", __func__, idx);
 347                         return (pt);
 348                 }
 349
 350                 pt = (const struct pppoe_tag*)ptn;
 351         }
 352
 353         CTR2(KTR_NET, "%20s: not found tag %d", __func__, idx);
 354         return (NULL);
 355 }
 356
 357 /**************************************************************************
 358  * Inlines to initialise or add tags to a session's tag list.
 359  **************************************************************************/
 360 /*
 361  * Initialise the session's tag list.
 362  */
 363 static void
 364 init_tags(sessp sp)
 365 {
 366         KASSERT(sp->neg != NULL, ("%s: no neg", __func__));
 367         sp->neg->numtags = 0;
 368 }
 369
 370 static void
 371 insert_tag(sessp sp, const struct pppoe_tag *tp)
 372 {
 373         negp neg = sp->neg;
 374         int i;
 375
 376         KASSERT(neg != NULL, ("%s: no neg", __func__));
 377         if ((i = neg->numtags++) < NUMTAGS) {
 378                 neg->tags[i] = tp;
 379         } else {
 380                 log(LOG_NOTICE, "ng_pppoe: asked to add too many tags to "
 381                     "packet\n");
 382                 neg->numtags--;
 383         }
 384 }
 385
 386 /*
 387  * Make up a packet, using the tags filled out for the session.
 388  *
 389  * Assume that the actual pppoe header and ethernet header
 390  * are filled out externally to this routine.
 391  * Also assume that neg->wh points to the correct
 392  * location at the front of the buffer space.
 393  */
 394 static void
 395 make_packet(sessp sp) {
 396         struct pppoe_full_hdr *wh = &sp->neg->pkt->pkt_header;
 397         const struct pppoe_tag **tag;
 398         char *dp;
 399         int count;
 400         int tlen;
 401         uint16_t length = 0;
 402
 403         KASSERT((sp->neg != NULL) && (sp->neg->m != NULL),
 404             ("%s: called from wrong state", __func__));
 405         CTR2(KTR_NET, "%20s: called %d", __func__, sp->Session_ID);
 406
 407         dp = (char *)(&wh->ph + 1);
 408         for (count = 0, tag = sp->neg->tags;
 409             ((count < sp->neg->numtags) && (count < NUMTAGS));
 410             tag++, count++) {
 411                 tlen = ntohs((*tag)->tag_len) + sizeof(**tag);
 412                 if ((length + tlen) > (ETHER_MAX_LEN - 4 - sizeof(*wh))) {
 413                         log(LOG_NOTICE, "ng_pppoe: tags too long\n");
 414                         sp->neg->numtags = count;
 415                         break;  /* XXX chop off what's too long */
 416                 }
 417                 bcopy(*tag, (char *)dp, tlen);
 418                 length += tlen;
 419                 dp += tlen;
 420         }
 421         wh->ph.length = htons(length);
 422         sp->neg->m->m_len = length + sizeof(*wh);
 423         sp->neg->m->m_pkthdr.len = length + sizeof(*wh);
 424 }
 425
 426 /**************************************************************************
 427  * Routines to match a service.                                           *
 428  **************************************************************************/
 429
 430 /*
 431  * Find a hook that has a service string that matches that
 432  * we are seeking. For now use a simple string.
 433  * In the future we may need something like regexp().
 434  *
 435  * Null string is a wildcard (ANY service), according to RFC2516.
 436  * And historical FreeBSD wildcard is also "*".
 437  */
 438
 439 static hook_p
 440 pppoe_match_svc(node_p node, const struct pppoe_tag *tag)
 441 {
 442         const priv_p privp = NG_NODE_PRIVATE(node);
 443         sessp sp;
 444
 445         LIST_FOREACH(sp, &privp->listeners, sessions) {
 446                 negp neg = sp->neg;
 447
 448                 /* Empty Service-Name matches any service. */
 449                 if (neg->service_len == 0)
 450                         break;
 451
 452                 /* Special case for a blank or "*" service name (wildcard). */
 453                 if (neg->service_len == 1 && neg->service.data[0] == '*')
 454                         break;
 455
 456                 /* If the lengths don't match, that aint it. */
 457                 if (neg->service_len != ntohs(tag->tag_len))
 458                         continue;
 459
 460                 if (strncmp((const char *)(tag + 1), neg->service.data,
 461                     ntohs(tag->tag_len)) == 0)
 462                         break;
 463         }
 464         CTR3(KTR_NET, "%20s: matched %p for %s", __func__,
 465             sp?sp->hook:NULL, (const char *)(tag + 1));
 466
 467         return (sp?sp->hook:NULL);
 468 }
 469
 470 /*
 471  * Broadcast the PADI packet in m0 to all listening hooks.
 472  * This routine is called when a PADI with empty Service-Name
 473  * tag is received. Client should receive PADOs with all
 474  * available services.
 475  */
 476 static int
 477 pppoe_broadcast_padi(node_p node, struct mbuf *m0)
 478 {
 479         const priv_p privp = NG_NODE_PRIVATE(node);
 480         sessp sp;
 481         int error = 0;
 482
 483         LIST_FOREACH(sp, &privp->listeners, sessions) {
 484                 struct mbuf *m;
 485
 486                 m = m_dup(m0, M_NOWAIT);
 487                 if (m == NULL)
 488                         return (ENOMEM);
 489                 NG_SEND_DATA_ONLY(error, sp->hook, m);
 490                 if (error)
 491                         return (error);
 492         }
 493
 494         return (0);
 495 }
 496
 497 /*
 498  * Find a hook, which name equals to given service.
 499  */
 500 static hook_p
 501 pppoe_find_svc(node_p node, const char *svc_name, int svc_len)
 502 {
 503         const priv_p privp = NG_NODE_PRIVATE(node);
 504         sessp sp;
 505
 506         LIST_FOREACH(sp, &privp->listeners, sessions) {
 507                 negp neg = sp->neg;
 508
 509                 if (neg->service_len == svc_len &&
 510                     strncmp(svc_name, neg->service.data, svc_len) == 0)
 511                         return (sp->hook);
 512         }
 513
 514         return (NULL);
 515 }
 516
 517 /**************************************************************************
 518  * Routines to find a particular session that matches an incoming packet. *
 519  **************************************************************************/
 520 /* Find free session and add to hash. */
 521 static uint16_t
 522 pppoe_getnewsession(sessp sp)
 523 {
 524         const priv_p privp = NG_NODE_PRIVATE(NG_HOOK_NODE(sp->hook));
 525         static uint16_t pppoe_sid = 1;
 526         sessp   tsp;
 527         uint16_t val, hash;
 528
 529 restart:
 530         /* Atomicity is not needed here as value will be checked. */
 531         val = pppoe_sid++;
 532         /* Spec says 0xFFFF is reserved, also don't use 0x0000. */
 533         if (val == 0xffff || val == 0x0000)
 534                 val = pppoe_sid = 1;
 535
 536         /* Check it isn't already in use. */
 537         hash = SESSHASH(val);
 538         mtx_lock(&privp->sesshash[hash].mtx);
 539         LIST_FOREACH(tsp, &privp->sesshash[hash].head, sessions) {
 540                 if (tsp->Session_ID == val)
 541                         break;
 542         }
 543         if (!tsp) {
 544                 sp->Session_ID = val;
 545                 LIST_INSERT_HEAD(&privp->sesshash[hash].head, sp, sessions);
 546         }
 547         mtx_unlock(&privp->sesshash[hash].mtx);
 548         if (tsp)
 549                 goto restart;
 550
 551         CTR2(KTR_NET, "%20s: new sid %d", __func__, val);
 552
 553         return (val);
 554 }
 555
 556 /* Add specified session to hash. */
 557 static void
 558 pppoe_addsession(sessp sp)
 559 {
 560         const priv_p    privp = NG_NODE_PRIVATE(NG_HOOK_NODE(sp->hook));
 561         uint16_t        hash = SESSHASH(sp->Session_ID);
 562
 563         mtx_lock(&privp->sesshash[hash].mtx);
 564         LIST_INSERT_HEAD(&privp->sesshash[hash].head, sp, sessions);
 565         mtx_unlock(&privp->sesshash[hash].mtx);
 566 }
 567
 568 /* Delete specified session from hash. */
 569 static void
 570 pppoe_delsession(sessp sp)
 571 {
 572         const priv_p    privp = NG_NODE_PRIVATE(NG_HOOK_NODE(sp->hook));
 573         uint16_t        hash = SESSHASH(sp->Session_ID);
 574
 575         mtx_lock(&privp->sesshash[hash].mtx);
 576         LIST_REMOVE(sp, sessions);
 577         mtx_unlock(&privp->sesshash[hash].mtx);
 578 }
 579
 580 /* Find matching peer/session combination. */
 581 static sessp
 582 pppoe_findsession(priv_p privp, const struct pppoe_full_hdr *wh)
 583 {
 584         uint16_t        session = ntohs(wh->ph.sid);
 585         uint16_t        hash = SESSHASH(session);
 586         sessp           sp = NULL;
 587
 588         mtx_lock(&privp->sesshash[hash].mtx);
 589         LIST_FOREACH(sp, &privp->sesshash[hash].head, sessions) {
 590                 if (sp->Session_ID == session &&
 591                     bcmp(sp->pkt_hdr.eh.ether_dhost,
 592                      wh->eh.ether_shost, ETHER_ADDR_LEN) == 0) {
 593                         break;
 594                 }
 595         }
 596         mtx_unlock(&privp->sesshash[hash].mtx);
 597         CTR3(KTR_NET, "%20s: matched %p for %d", __func__, sp?sp->hook:NULL,
 598             session);
 599
 600         return (sp);
 601 }
 602
 603 static hook_p
 604 pppoe_finduniq(node_p node, const struct pppoe_tag *tag)
 605 {
 606         hook_p  hook = NULL;
 607         sessp   sp;
 608
 609         /* Cycle through all known hooks. */
 610         LIST_FOREACH(hook, &node->nd_hooks, hk_hooks) {
 611                 /* Skip any nonsession hook. */
 612                 if (NG_HOOK_PRIVATE(hook) == NULL)
 613                         continue;
 614                 sp = NG_HOOK_PRIVATE(hook);
 615                 /* Skip already connected sessions. */
 616                 if (sp->neg == NULL)
 617                         continue;
 618                 if (sp->neg->host_uniq_len == ntohs(tag->tag_len) &&
 619                     bcmp(sp->neg->host_uniq.data, (const char *)(tag + 1),
 620                      sp->neg->host_uniq_len) == 0)
 621                         break;
 622         }
 623         CTR3(KTR_NET, "%20s: matched %p for %p", __func__, hook, sp);
 624
 625         return (hook);
 626 }
 627
 628 static hook_p
 629 pppoe_findcookie(node_p node, const struct pppoe_tag *tag)
 630 {
 631         hook_p  hook = NULL;
 632         union uniq cookie;
 633
 634         bcopy(tag + 1, cookie.bytes, sizeof(void *));
 635         /* Cycle through all known hooks. */
 636         LIST_FOREACH(hook, &node->nd_hooks, hk_hooks) {
 637                 /* Skip any nonsession hook. */
 638                 if (NG_HOOK_PRIVATE(hook) == NULL)
 639                         continue;
 640                 if (cookie.pointer == NG_HOOK_PRIVATE(hook))
 641                         break;
 642         }
 643         CTR3(KTR_NET, "%20s: matched %p for %p", __func__, hook, cookie.pointer);
 644
 645         return (hook);
 646 }
 647
 648 /**************************************************************************
 649  * Start of Netgraph entrypoints.                                         *
 650  **************************************************************************/
 651
 652 /*
 653  * Allocate the private data structure and link it with node.
 654  */
 655 static int
 656 ng_pppoe_constructor(node_p node)
 657 {
 658         priv_p  privp;
 659         int     i;
 660
 661         /* Initialize private descriptor. */
 662         privp = malloc(sizeof(*privp), M_NETGRAPH_PPPOE, M_WAITOK | M_ZERO);
 663
 664         /* Link structs together; this counts as our one reference to *node. */
 665         NG_NODE_SET_PRIVATE(node, privp);
 666         privp->node = node;
 667
 668         /* Initialize to standard mode. */
 669         memset(&privp->eh.ether_dhost, 0xff, ETHER_ADDR_LEN);
 670         privp->eh.ether_type = ETHERTYPE_PPPOE_DISC;
 671
 672         LIST_INIT(&privp->listeners);
 673         for (i = 0; i < SESSHASHSIZE; i++) {
 674             mtx_init(&privp->sesshash[i].mtx, "PPPoE hash mutex", NULL, MTX_DEF);
 675             LIST_INIT(&privp->sesshash[i].head);
 676         }
 677
 678         CTR3(KTR_NET, "%20s: created node [%x] (%p)",
 679             __func__, node->nd_ID, node);
 680
 681         return (0);
 682 }
 683
 684 /*
 685  * Give our ok for a hook to be added...
 686  * point the hook's private info to the hook structure.
 687  *
 688  * The following hook names are special:
 689  *  "ethernet":  the hook that should be connected to a NIC.
 690  *  "debug":    copies of data sent out here  (when I write the code).
 691  * All other hook names need only be unique. (the framework checks this).
 692  */
 693 static int
 694 ng_pppoe_newhook(node_p node, hook_p hook, const char *name)
 695 {
 696         const priv_p privp = NG_NODE_PRIVATE(node);
 697         sessp sp;
 698
 699         if (strcmp(name, NG_PPPOE_HOOK_ETHERNET) == 0) {
 700                 privp->ethernet_hook = hook;
 701                 NG_HOOK_SET_RCVDATA(hook, ng_pppoe_rcvdata_ether);
 702         } else if (strcmp(name, NG_PPPOE_HOOK_DEBUG) == 0) {
 703                 privp->debug_hook = hook;
 704                 NG_HOOK_SET_RCVDATA(hook, ng_pppoe_rcvdata_debug);
 705         } else {
 706                 /*
 707                  * Any other unique name is OK.
 708                  * The infrastructure has already checked that it's unique,
 709                  * so just allocate it and hook it in.
 710                  */
 711                 sp = malloc(sizeof(*sp), M_NETGRAPH_PPPOE, M_NOWAIT | M_ZERO);
 712                 if (sp == NULL)
 713                         return (ENOMEM);
 714
 715                 NG_HOOK_SET_PRIVATE(hook, sp);
 716                 sp->hook = hook;
 717         }
 718         CTR5(KTR_NET, "%20s: node [%x] (%p) connected hook %s (%p)",
 719             __func__, node->nd_ID, node, name, hook);
 720
 721         return(0);
 722 }
 723
 724 /*
 725  * Hook has been added successfully. Request the MAC address of
 726  * the underlying Ethernet node.
 727  */
 728 static int
 729 ng_pppoe_connect(hook_p hook)
 730 {
 731         const priv_p privp = NG_NODE_PRIVATE(NG_HOOK_NODE(hook));
 732         struct ng_mesg *msg;
 733         int error;
 734
 735         if (hook != privp->ethernet_hook)
 736                 return (0);
 737
 738         /*
 739          * If this is Ethernet hook, then request MAC address
 740          * from our downstream.
 741          */
 742         NG_MKMESSAGE(msg, NGM_ETHER_COOKIE, NGM_ETHER_GET_ENADDR, 0, M_NOWAIT);
 743         if (msg == NULL)
 744                 return (ENOBUFS);
 745
 746         /*
 747          * Our hook and peer hook have HK_INVALID flag set,
 748          * so we can't use NG_SEND_MSG_HOOK() macro here.
 749          */
 750         NG_SEND_MSG_ID(error, privp->node, msg,
 751             NG_NODE_ID(NG_PEER_NODE(privp->ethernet_hook)),
 752             NG_NODE_ID(privp->node));
 753
 754         return (error);
 755 }
 756 /*
 757  * Get a netgraph control message.
 758  * Check it is one we understand. If needed, send a response.
 759  * We sometimes save the address for an async action later.
 760  * Always free the message.
 761  */
 762 static int
 763 ng_pppoe_rcvmsg(node_p node, item_p item, hook_p lasthook)
 764 {
 765         struct epoch_tracker et;
 766         priv_p privp = NG_NODE_PRIVATE(node);
 767         struct ngpppoe_init_data *ourmsg = NULL;
 768         struct ng_mesg *resp = NULL;
 769         int error = 0;
 770         hook_p hook = NULL;
 771         sessp sp = NULL;
 772         negp neg = NULL;
 773         struct ng_mesg *msg;
 774
 775         NGI_GET_MSG(item, msg);
 776         CTR5(KTR_NET, "%20s: node [%x] (%p) got message %d with cookie %d",
 777             __func__, node->nd_ID, node, msg->header.cmd,
 778             msg->header.typecookie);
 779
 780         /* Deal with message according to cookie and command. */
 781         switch (msg->header.typecookie) {
 782         case NGM_PPPOE_COOKIE:
 783                 switch (msg->header.cmd) {
 784                 case NGM_PPPOE_CONNECT:
 785                 case NGM_PPPOE_LISTEN:
 786                 case NGM_PPPOE_OFFER:
 787                 case NGM_PPPOE_SERVICE:
 788                 case NGM_PPPOE_SEND_HURL:
 789                 case NGM_PPPOE_SEND_MOTM:
 790                         ourmsg = (struct ngpppoe_init_data *)msg->data;
 791                         if (msg->header.arglen < sizeof(*ourmsg)) {
 792                                 log(LOG_ERR, "ng_pppoe[%x]: init data too "
 793                                     "small\n", node->nd_ID);
 794                                 LEAVE(EMSGSIZE);
 795                         }
 796                         if (msg->header.cmd == NGM_PPPOE_SEND_HURL ||
 797                             msg->header.cmd == NGM_PPPOE_SEND_MOTM) {
 798                                 if (msg->header.arglen - sizeof(*ourmsg) >
 799                                     PPPOE_PADM_VALUE_SIZE) {
 800                                         log(LOG_ERR, "ng_pppoe[%x]: message "
 801                                             "too big\n", node->nd_ID);
 802                                         LEAVE(EMSGSIZE);
 803                                 }
 804                         } else {
 805                                 if (msg->header.arglen - sizeof(*ourmsg) >
 806                                     PPPOE_SERVICE_NAME_SIZE) {
 807                                         log(LOG_ERR, "ng_pppoe[%x]: service name "
 808                                             "too big\n", node->nd_ID);
 809                                         LEAVE(EMSGSIZE);
 810                                 }
 811                         }
 812                         if (msg->header.arglen - sizeof(*ourmsg) <
 813                             ourmsg->data_len) {
 814                                 log(LOG_ERR, "ng_pppoe[%x]: init data has bad "
 815                                     "length, %d should be %zd\n", node->nd_ID,
 816                                     ourmsg->data_len,
 817                                     msg->header.arglen - sizeof (*ourmsg));
 818                                 LEAVE(EMSGSIZE);
 819                         }
 820
 821                         /* Make sure strcmp will terminate safely. */
 822                         ourmsg->hook[sizeof(ourmsg->hook) - 1] = '\0';
 823
 824                         /* Find hook by name. */
 825                         hook = ng_findhook(node, ourmsg->hook);
 826                         if (hook == NULL)
 827                                 LEAVE(ENOENT);
 828
 829                         sp = NG_HOOK_PRIVATE(hook);
 830                         if (sp == NULL)
 831                                 LEAVE(EINVAL);
 832
 833                         if (msg->header.cmd == NGM_PPPOE_LISTEN) {
 834                                 /*
 835                                  * Ensure we aren't already listening for this
 836                                  * service.
 837                                  */
 838                                 if (pppoe_find_svc(node, ourmsg->data,
 839                                     ourmsg->data_len) != NULL)
 840                                         LEAVE(EEXIST);
 841                         }
 842
 843                         /*
 844                          * PPPOE_SERVICE advertisements are set up
 845                          * on sessions that are in PRIMED state.
 846                          */
 847                         if (msg->header.cmd == NGM_PPPOE_SERVICE)
 848                                 break;
 849
 850                         /*
 851                          * PADM messages are set up on active sessions.
 852                          */
 853                         if (msg->header.cmd == NGM_PPPOE_SEND_HURL ||
 854                             msg->header.cmd == NGM_PPPOE_SEND_MOTM) {
 855                                 if (sp->state != PPPOE_NEWCONNECTED &&
 856                                     sp->state != PPPOE_CONNECTED) {
 857                                         log(LOG_NOTICE, "ng_pppoe[%x]: session is not "
 858                                             "active\n", node->nd_ID);
 859                                         LEAVE(EISCONN);
 860                                 }
 861                                 break;
 862                         }
 863
 864                         if (sp->state != PPPOE_SNONE) {
 865                                 log(LOG_NOTICE, "ng_pppoe[%x]: Session already "
 866                                     "active\n", node->nd_ID);
 867                                 LEAVE(EISCONN);
 868                         }
 869
 870                         /*
 871                          * Set up prototype header.
 872                          */
 873                         neg = malloc(sizeof(*neg), M_NETGRAPH_PPPOE,
 874                             M_NOWAIT | M_ZERO);
 875
 876                         if (neg == NULL)
 877                                 LEAVE(ENOMEM);
 878
 879                         neg->m = m_getcl(M_NOWAIT, MT_DATA, M_PKTHDR);
 880                         if (neg->m == NULL) {
 881                                 free(neg, M_NETGRAPH_PPPOE);
 882                                 LEAVE(ENOBUFS);
 883                         }
 884                         neg->m->m_pkthdr.rcvif = NULL;
 885                         sp->neg = neg;
 886                         ng_callout_init(&neg->handle);
 887                         neg->m->m_len = sizeof(struct pppoe_full_hdr);
 888                         neg->pkt = mtod(neg->m, union packet*);
 889                         memcpy((void *)&neg->pkt->pkt_header.eh,
 890                             &privp->eh, sizeof(struct ether_header));
 891                         neg->pkt->pkt_header.ph.ver = 0x1;
 892                         neg->pkt->pkt_header.ph.type = 0x1;
 893                         neg->pkt->pkt_header.ph.sid = 0x0000;
 894                         neg->timeout = 0;
 895
 896                         sp->creator = NGI_RETADDR(item);
 897                 }
 898                 switch (msg->header.cmd) {
 899                 case NGM_PPPOE_GET_STATUS:
 900                     {
 901                         struct ngpppoestat *stats;
 902
 903                         NG_MKRESPONSE(resp, msg, sizeof(*stats), M_NOWAIT);
 904                         if (!resp)
 905                                 LEAVE(ENOMEM);
 906
 907                         stats = (struct ngpppoestat *) resp->data;
 908                         stats->packets_in = privp->packets_in;
 909                         stats->packets_out = privp->packets_out;
 910                         break;
 911                     }
 912                 case NGM_PPPOE_CONNECT:
 913                     {
 914                         /*
 915                          * Check the hook exists and is Uninitialised.
 916                          * Send a PADI request, and start the timeout logic.
 917                          * Store the originator of this message so we can send
 918                          * a success or fail message to them later.
 919                          * Move the session to SINIT.
 920                          * Set up the session to the correct state and
 921                          * start it.
 922                          */
 923                         int     acnpos, acnlen = 0, acnsep = 0;
 924                         int     hupos, hulen = 0, husep = 0;
 925                         int     i, srvpos, srvlen;
 926                         acnpos = 0;
 927                         for (i = 0; i < ourmsg->data_len; i++) {
 928                                 if (ourmsg->data[i] == '\\') {
 929                                         acnlen = i;
 930                                         acnsep = 1;
 931                                         break;
 932                                 }
 933                         }
 934                         hupos = acnlen + acnsep;
 935                         for (i = hupos; i < ourmsg->data_len; i++) {
 936                                 if (ourmsg->data[i] == '|') {
 937                                         hulen = i - hupos;
 938                                         husep = 1;
 939                                         break;
 940                                 }
 941                         }
 942                         srvpos = hupos + hulen + husep;
 943                         srvlen = ourmsg->data_len - srvpos;
 944
 945                         bcopy(ourmsg->data + acnpos, neg->ac_name.data, acnlen);
 946                         neg->ac_name_len = acnlen;
 947
 948                         neg->host_uniq.hdr.tag_type = PTT_HOST_UNIQ;
 949                         if (hulen == 0) {
 950                                 /* Not provided, generate one */
 951                                 neg->host_uniq.hdr.tag_len = htons(sizeof(sp));
 952                                 bcopy(&sp, neg->host_uniq.data, sizeof(sp));
 953                                 neg->host_uniq_len = sizeof(sp);
 954                         } else if (hulen > 2 && ourmsg->data[hupos] == '0' &&
 955                           ourmsg->data[hupos + 1] == 'x' && hulen % 2 == 0) {
 956                                 /* Hex encoded */
 957                                 static const char hexdig[16] = "0123456789abcdef";
 958                                 int j;
 959
 960                                 neg->host_uniq.hdr.tag_len = htons((uint16_t)(hulen / 2 - 1));
 961                                 for (i = 0; i < hulen - 2; i++) {
 962                                         for (j = 0;
 963                                              j < 16 &&
 964                                              ourmsg->data[hupos + 2 + i] != hexdig[j];
 965                                              j++);
 966                                         if (j == 16)
 967                                                 LEAVE(EINVAL);
 968                                         if (i % 2 == 0)
 969                                                 neg->host_uniq.data[i / 2] = j << 4;
 970                                         else
 971                                                 neg->host_uniq.data[i / 2] |= j;
 972                                 }
 973                                 neg->host_uniq_len = hulen / 2 - 1;
 974                         } else {
 975                                 /* Plain string */
 976                                 neg->host_uniq.hdr.tag_len = htons((uint16_t)hulen);
 977                                 bcopy(ourmsg->data + hupos, neg->host_uniq.data, hulen);
 978                                 neg->host_uniq_len = hulen;
 979                         }
 980
 981                         neg->service.hdr.tag_type = PTT_SRV_NAME;
 982                         neg->service.hdr.tag_len = htons((uint16_t)srvlen);
 983                         bcopy(ourmsg->data + srvpos, neg->service.data, srvlen);
 984                         neg->service_len = srvlen;
 985                         NET_EPOCH_ENTER(et);
 986                         pppoe_start(sp);
 987                         NET_EPOCH_EXIT(et);
 988                         break;
 989                     }
 990                 case NGM_PPPOE_LISTEN:
 991                         /*
 992                          * Check the hook exists and is Uninitialised.
 993                          * Install the service matching string.
 994                          * Store the originator of this message so we can send
 995                          * a success or fail message to them later.
 996                          * Move the hook to 'LISTENING'
 997                          */
 998                         neg->service.hdr.tag_type = PTT_SRV_NAME;
 999                         neg->service.hdr.tag_len =
1000                             htons((uint16_t)ourmsg->data_len);
1001
1002                         if (ourmsg->data_len)
1003                                 bcopy(ourmsg->data, neg->service.data,
1004                                     ourmsg->data_len);
1005                         neg->service_len = ourmsg->data_len;
1006                         neg->pkt->pkt_header.ph.code = PADT_CODE;
1007                         /*
1008                          * Wait for PADI packet coming from Ethernet.
1009                          */
1010                         sp->state = PPPOE_LISTENING;
1011                         LIST_INSERT_HEAD(&privp->listeners, sp, sessions);
1012                         break;
1013                 case NGM_PPPOE_OFFER:
1014                         /*
1015                          * Check the hook exists and is Uninitialised.
1016                          * Store the originator of this message so we can send
1017                          * a success of fail message to them later.
1018                          * Store the AC-Name given and go to PRIMED.
1019                          */
1020                         neg->ac_name.hdr.tag_type = PTT_AC_NAME;
1021                         neg->ac_name.hdr.tag_len =
1022                             htons((uint16_t)ourmsg->data_len);
1023                         if (ourmsg->data_len)
1024                                 bcopy(ourmsg->data, neg->ac_name.data,
1025                                     ourmsg->data_len);
1026                         neg->ac_name_len = ourmsg->data_len;
1027                         neg->pkt->pkt_header.ph.code = PADO_CODE;
1028                         /*
1029                          * Wait for PADI packet coming from hook.
1030                          */
1031                         sp->state = PPPOE_PRIMED;
1032                         break;
1033                 case NGM_PPPOE_SERVICE:
1034                         /*
1035                          * Check the session is primed.
1036                          * for now just allow ONE service to be advertised.
1037                          * If you do it twice you just overwrite.
1038                          */
1039                         if (sp->state != PPPOE_PRIMED) {
1040                                 log(LOG_NOTICE, "ng_pppoe[%x]: session not "
1041                                     "primed\n", node->nd_ID);
1042                                 LEAVE(EISCONN);
1043                         }
1044                         neg = sp->neg;
1045                         neg->service.hdr.tag_type = PTT_SRV_NAME;
1046                         neg->service.hdr.tag_len =
1047                             htons((uint16_t)ourmsg->data_len);
1048
1049                         if (ourmsg->data_len)
1050                                 bcopy(ourmsg->data, neg->service.data,
1051                                     ourmsg->data_len);
1052                         neg->service_len = ourmsg->data_len;
1053                         break;
1054                 case NGM_PPPOE_SETMODE:
1055                     {
1056                         char *s;
1057                         size_t len;
1058
1059                         if (msg->header.arglen == 0)
1060                                 LEAVE(EINVAL);
1061
1062                         s = (char *)msg->data;
1063                         len = msg->header.arglen - 1;
1064
1065                         /* Search for matching mode string. */
1066                         if (len == strlen(NG_PPPOE_STANDARD) &&
1067                             (strncmp(NG_PPPOE_STANDARD, s, len) == 0)) {
1068                                 privp->flags = 0;
1069                                 privp->eh.ether_type = ETHERTYPE_PPPOE_DISC;
1070                                 break;
1071                         }
1072                         if (len == strlen(NG_PPPOE_3COM) &&
1073                             (strncmp(NG_PPPOE_3COM, s, len) == 0)) {
1074                                 privp->flags |= COMPAT_3COM;
1075                                 privp->eh.ether_type =
1076                                     ETHERTYPE_PPPOE_3COM_DISC;
1077                                 break;
1078                         }
1079                         if (len == strlen(NG_PPPOE_DLINK) &&
1080                             (strncmp(NG_PPPOE_DLINK, s, len) == 0)) {
1081                                 privp->flags |= COMPAT_DLINK;
1082                                 break;
1083                         }
1084                         error = EINVAL;
1085                         break;
1086                     }
1087                 case NGM_PPPOE_GETMODE:
1088                     {
1089                         char *s;
1090                         size_t len = 0;
1091
1092                         if (privp->flags == 0)
1093                                 len += strlen(NG_PPPOE_STANDARD) + 1;
1094                         if (privp->flags & COMPAT_3COM)
1095                                 len += strlen(NG_PPPOE_3COM) + 1;
1096                         if (privp->flags & COMPAT_DLINK)
1097                                 len += strlen(NG_PPPOE_DLINK) + 1;
1098
1099                         NG_MKRESPONSE(resp, msg, len, M_NOWAIT);
1100                         if (resp == NULL)
1101                                 LEAVE(ENOMEM);
1102
1103                         s = (char *)resp->data;
1104                         if (privp->flags == 0) {
1105                                 len = strlen(NG_PPPOE_STANDARD);
1106                                 strlcpy(s, NG_PPPOE_STANDARD, len + 1);
1107                                 break;
1108                         }
1109                         if (privp->flags & COMPAT_3COM) {
1110                                 len = strlen(NG_PPPOE_3COM);
1111                                 strlcpy(s, NG_PPPOE_3COM, len + 1);
1112                                 s += len;
1113                         }
1114                         if (privp->flags & COMPAT_DLINK) {
1115                                 if (s != resp->data)
1116                                         *s++ = '|';
1117                                 len = strlen(NG_PPPOE_DLINK);
1118                                 strlcpy(s, NG_PPPOE_DLINK, len + 1);
1119                         }
1120                         break;
1121                     }
1122                 case NGM_PPPOE_SETENADDR:
1123                         if (msg->header.arglen != ETHER_ADDR_LEN)
1124                                 LEAVE(EINVAL);
1125                         bcopy(msg->data, &privp->eh.ether_shost,
1126                             ETHER_ADDR_LEN);
1127                         break;
1128                 case NGM_PPPOE_SETMAXP:
1129                         if (msg->header.arglen != sizeof(uint16_t))
1130                                 LEAVE(EINVAL);
1131                         privp->max_payload.hdr.tag_type = PTT_MAX_PAYL;
1132                         privp->max_payload.hdr.tag_len = htons(sizeof(uint16_t));
1133                         privp->max_payload.data = htons(*((uint16_t *)msg->data));
1134                         break;
1135                 case NGM_PPPOE_SEND_HURL:
1136                     {
1137                         struct mbuf *m;
1138
1139                         /* Generate a packet of that type. */
1140                         m = m_gethdr(M_NOWAIT, MT_DATA);
1141                         if (m == NULL)
1142                                 log(LOG_NOTICE, "ng_pppoe[%x]: session out of "
1143                                     "mbufs\n", node->nd_ID);
1144                         else {
1145                                 struct pppoe_full_hdr *wh;
1146                                 struct pppoe_tag *tag;
1147                                 int     error = 0;
1148
1149                                 wh = mtod(m, struct pppoe_full_hdr *);
1150                                 bcopy(&sp->pkt_hdr, wh, sizeof(*wh));
1151
1152                                 /* Revert the stored header to DISC/PADM mode. */
1153                                 wh->ph.code = PADM_CODE;
1154                                 /*
1155                                  * Configure ethertype depending on what
1156                                  * was used during sessions stage.
1157                                  */
1158                                 if (wh->eh.ether_type ==
1159                                     ETHERTYPE_PPPOE_3COM_SESS)
1160                                         wh->eh.ether_type = ETHERTYPE_PPPOE_3COM_DISC;
1161                                 else
1162                                         wh->eh.ether_type = ETHERTYPE_PPPOE_DISC;
1163                                 /*
1164                                  * Add PADM message and adjust sizes.
1165                                  */
1166                                 tag = (void *)(&wh->ph + 1);
1167                                 tag->tag_type = PTT_HURL;
1168                                 tag->tag_len = htons(ourmsg->data_len);
1169                                 strncpy((char *)(tag + 1), ourmsg->data, ourmsg->data_len);
1170                                 m->m_pkthdr.len = m->m_len = sizeof(*wh) + sizeof(*tag) +
1171                                     ourmsg->data_len;
1172                                 wh->ph.length = htons(sizeof(*tag) + ourmsg->data_len);
1173                                 NET_EPOCH_ENTER(et);
1174                                 NG_SEND_DATA_ONLY(error,
1175                                     privp->ethernet_hook, m);
1176                                 NET_EPOCH_EXIT(et);
1177                         }
1178                         break;
1179                     }
1180                 case NGM_PPPOE_SEND_MOTM:
1181                     {
1182                         struct mbuf *m;
1183
1184                         /* Generate a packet of that type. */
1185                         m = m_gethdr(M_NOWAIT, MT_DATA);
1186                         if (m == NULL)
1187                                 log(LOG_NOTICE, "ng_pppoe[%x]: session out of "
1188                                     "mbufs\n", node->nd_ID);
1189                         else {
1190                                 struct pppoe_full_hdr *wh;
1191                                 struct pppoe_tag *tag;
1192                                 int     error = 0;
1193
1194                                 wh = mtod(m, struct pppoe_full_hdr *);
1195                                 bcopy(&sp->pkt_hdr, wh, sizeof(*wh));
1196
1197                                 /* Revert the stored header to DISC/PADM mode. */
1198                                 wh->ph.code = PADM_CODE;
1199                                 /*
1200                                  * Configure ethertype depending on what
1201                                  * was used during sessions stage.
1202                                  */
1203                                 if (wh->eh.ether_type ==
1204                                     ETHERTYPE_PPPOE_3COM_SESS)
1205                                         wh->eh.ether_type = ETHERTYPE_PPPOE_3COM_DISC;
1206                                 else
1207                                         wh->eh.ether_type = ETHERTYPE_PPPOE_DISC;
1208                                 /*
1209                                  * Add PADM message and adjust sizes.
1210                                  */
1211                                 tag = (void *)(&wh->ph + 1);
1212                                 tag->tag_type = PTT_MOTM;
1213                                 tag->tag_len = htons(ourmsg->data_len);
1214                                 strncpy((char *)(tag + 1), ourmsg->data, ourmsg->data_len);
1215                                 m->m_pkthdr.len = m->m_len = sizeof(*wh) + sizeof(*tag) +
1216                                     ourmsg->data_len;
1217                                 wh->ph.length = htons(sizeof(*tag) + ourmsg->data_len);
1218                                 NET_EPOCH_ENTER(et);
1219                                 NG_SEND_DATA_ONLY(error,
1220                                     privp->ethernet_hook, m);
1221                                 NET_EPOCH_EXIT(et);
1222                         }
1223                         break;
1224                     }
1225                 default:
1226                         LEAVE(EINVAL);
1227                 }
1228                 break;
1229         case NGM_ETHER_COOKIE:
1230                 if (!(msg->header.flags & NGF_RESP))
1231                         LEAVE(EINVAL);
1232                 switch (msg->header.cmd) {
1233                 case NGM_ETHER_GET_ENADDR:
1234                         if (msg->header.arglen != ETHER_ADDR_LEN)
1235                                 LEAVE(EINVAL);
1236                         bcopy(msg->data, &privp->eh.ether_shost,
1237                             ETHER_ADDR_LEN);
1238                         break;
1239                 default:
1240                         LEAVE(EINVAL);
1241                 }
1242                 break;
1243         default:
1244                 LEAVE(EINVAL);
1245         }
1246
1247         /* Take care of synchronous response, if any. */
1248 quit:
1249         CTR2(KTR_NET, "%20s: returning %d", __func__, error);
1250         NG_RESPOND_MSG(error, node, item, resp);
1251         /* Free the message and return. */
1252         NG_FREE_MSG(msg);
1253         return(error);
1254 }
1255
1256 /*
1257  * Start a client into the first state. A separate function because
1258  * it can be needed if the negotiation times out.
1259  */
1260 static void
1261 pppoe_start(sessp sp)
1262 {
1263         hook_p  hook = sp->hook;
1264         node_p  node = NG_HOOK_NODE(hook);
1265         priv_p  privp = NG_NODE_PRIVATE(node);
1266         negp    neg = sp->neg;
1267         struct  mbuf *m0;
1268         int     error;
1269
1270         /*
1271          * Kick the state machine into starting up.
1272          */
1273         CTR2(KTR_NET, "%20s: called %d", __func__, sp->Session_ID);
1274         sp->state = PPPOE_SINIT;
1275         /*
1276          * Reset the packet header to broadcast. Since we are
1277          * in a client mode use configured ethertype.
1278          */
1279         memcpy((void *)&neg->pkt->pkt_header.eh, &privp->eh,
1280             sizeof(struct ether_header));
1281         neg->pkt->pkt_header.ph.code = PADI_CODE;
1282         init_tags(sp);
1283         insert_tag(sp, &neg->host_uniq.hdr);
1284         insert_tag(sp, &neg->service.hdr);
1285         if (privp->max_payload.data != 0)
1286                 insert_tag(sp, &privp->max_payload.hdr);
1287         make_packet(sp);
1288         /*
1289          * Send packet and prepare to retransmit it after timeout.
1290          */
1291         ng_callout(&neg->handle, node, hook, PPPOE_INITIAL_TIMEOUT * hz,
1292             pppoe_ticker, NULL, 0);
1293         neg->timeout = PPPOE_INITIAL_TIMEOUT * 2;
1294         m0 = m_copypacket(neg->m, M_NOWAIT);
1295         NG_SEND_DATA_ONLY(error, privp->ethernet_hook, m0);
1296 }
1297
1298 static int
1299 send_acname(sessp sp, const struct pppoe_tag *tag)
1300 {
1301         int error, tlen;
1302         struct ng_mesg *msg;
1303         struct ngpppoe_sts *sts;
1304
1305         CTR2(KTR_NET, "%20s: called %d", __func__, sp->Session_ID);
1306
1307         NG_MKMESSAGE(msg, NGM_PPPOE_COOKIE, NGM_PPPOE_ACNAME,
1308             sizeof(struct ngpppoe_sts), M_NOWAIT);
1309         if (msg == NULL)
1310                 return (ENOMEM);
1311
1312         sts = (struct ngpppoe_sts *)msg->data;
1313         tlen = min(NG_HOOKSIZ - 1, ntohs(tag->tag_len));
1314         strncpy(sts->hook, (const char *)(tag + 1), tlen);
1315         sts->hook[tlen] = '\0';
1316         NG_SEND_MSG_ID(error, NG_HOOK_NODE(sp->hook), msg, sp->creator, 0);
1317
1318         return (error);
1319 }
1320
1321 static int
1322 send_sessionid(sessp sp)
1323 {
1324         int error;
1325         struct ng_mesg *msg;
1326
1327         CTR2(KTR_NET, "%20s: called %d", __func__, sp->Session_ID);
1328
1329         NG_MKMESSAGE(msg, NGM_PPPOE_COOKIE, NGM_PPPOE_SESSIONID,
1330             sizeof(uint16_t), M_NOWAIT);
1331         if (msg == NULL)
1332                 return (ENOMEM);
1333
1334         *(uint16_t *)msg->data = sp->Session_ID;
1335         NG_SEND_MSG_ID(error, NG_HOOK_NODE(sp->hook), msg, sp->creator, 0);
1336
1337         return (error);
1338 }
1339
1340 static int
1341 send_maxp(sessp sp, const struct pppoe_tag *tag)
1342 {
1343         int error;
1344         struct ng_mesg *msg;
1345         struct ngpppoe_maxp *maxp;
1346
1347         CTR2(KTR_NET, "%20s: called %d", __func__, sp->Session_ID);
1348
1349         NG_MKMESSAGE(msg, NGM_PPPOE_COOKIE, NGM_PPPOE_SETMAXP,
1350             sizeof(struct ngpppoe_maxp), M_NOWAIT);
1351         if (msg == NULL)
1352                 return (ENOMEM);
1353
1354         maxp = (struct ngpppoe_maxp *)msg->data;
1355         strncpy(maxp->hook, NG_HOOK_NAME(sp->hook), NG_HOOKSIZ);
1356         maxp->data = ntohs(((const struct maxptag *)tag)->data);
1357         NG_SEND_MSG_ID(error, NG_HOOK_NODE(sp->hook), msg, sp->creator, 0);
1358
1359         return (error);
1360 }
1361
1362 static int
1363 send_hurl(sessp sp, const struct pppoe_tag *tag)
1364 {
1365         int error, tlen;
1366         struct ng_mesg *msg;
1367         struct ngpppoe_padm *padm;
1368
1369         CTR2(KTR_NET, "%20s: called %d", __func__, sp->Session_ID);
1370
1371         NG_MKMESSAGE(msg, NGM_PPPOE_COOKIE, NGM_PPPOE_HURL,
1372             sizeof(struct ngpppoe_padm), M_NOWAIT);
1373         if (msg == NULL)
1374                 return (ENOMEM);
1375
1376         padm = (struct ngpppoe_padm *)msg->data;
1377         tlen = min(PPPOE_PADM_VALUE_SIZE - 1, ntohs(tag->tag_len));
1378         strncpy(padm->msg, (const char *)(tag + 1), tlen);
1379         padm->msg[tlen] = '\0';
1380         NG_SEND_MSG_ID(error, NG_HOOK_NODE(sp->hook), msg, sp->creator, 0);
1381
1382         return (error);
1383 }
1384
1385 static int
1386 send_motm(sessp sp, const struct pppoe_tag *tag)
1387 {
1388         int error, tlen;
1389         struct ng_mesg *msg;
1390         struct ngpppoe_padm *padm;
1391
1392         CTR2(KTR_NET, "%20s: called %d", __func__, sp->Session_ID);
1393
1394         NG_MKMESSAGE(msg, NGM_PPPOE_COOKIE, NGM_PPPOE_MOTM,
1395             sizeof(struct ngpppoe_padm), M_NOWAIT);
1396         if (msg == NULL)
1397                 return (ENOMEM);
1398
1399         padm = (struct ngpppoe_padm *)msg->data;
1400         tlen = min(PPPOE_PADM_VALUE_SIZE - 1, ntohs(tag->tag_len));
1401         strncpy(padm->msg, (const char *)(tag + 1), tlen);
1402         padm->msg[tlen] = '\0';
1403         NG_SEND_MSG_ID(error, NG_HOOK_NODE(sp->hook), msg, sp->creator, 0);
1404
1405         return (error);
1406 }
1407
1408 /*
1409  * Receive data from session hook and do something with it.
1410  */
1411 static int
1412 ng_pppoe_rcvdata(hook_p hook, item_p item)
1413 {
1414         node_p                  node = NG_HOOK_NODE(hook);
1415         const priv_p            privp = NG_NODE_PRIVATE(node);
1416         sessp                   sp = NG_HOOK_PRIVATE(hook);
1417         struct pppoe_full_hdr   *wh;
1418         struct mbuf             *m;
1419         int                     error;
1420
1421         CTR6(KTR_NET, "%20s: node [%x] (%p) received %p on \"%s\" (%p)",
1422             __func__, node->nd_ID, node, item, hook->hk_name, hook);
1423
1424         NGI_GET_M(item, m);
1425         switch (sp->state) {
1426         case    PPPOE_NEWCONNECTED:
1427         case    PPPOE_CONNECTED: {
1428                 /*
1429                  * Remove PPP address and control fields, if any.
1430                  * For example, ng_ppp(4) always sends LCP packets
1431                  * with address and control fields as required by
1432                  * generic PPP. PPPoE is an exception to the rule.
1433                  */
1434                 if (m->m_pkthdr.len >= 2) {
1435                         if (m->m_len < 2 && !(m = m_pullup(m, 2)))
1436                                 LEAVE(ENOBUFS);
1437                         if (mtod(m, u_char *)[0] == 0xff &&
1438                             mtod(m, u_char *)[1] == 0x03)
1439                                 m_adj(m, 2);
1440                 }
1441                 /*
1442                  * Bang in a pre-made header, and set the length up
1443                  * to be correct. Then send it to the ethernet driver.
1444                  */
1445                 M_PREPEND(m, sizeof(*wh), M_NOWAIT);
1446                 if (m == NULL)
1447                         LEAVE(ENOBUFS);
1448
1449                 wh = mtod(m, struct pppoe_full_hdr *);
1450                 bcopy(&sp->pkt_hdr, wh, sizeof(*wh));
1451                 wh->ph.length = htons(m->m_pkthdr.len - sizeof(*wh));
1452                 NG_FWD_NEW_DATA(error, item, privp->ethernet_hook, m);
1453                 privp->packets_out++;
1454                 break;
1455                 }
1456         case    PPPOE_PRIMED: {
1457                 struct {
1458                         struct pppoe_tag hdr;
1459                         union   uniq    data;
1460                 } __packed      uniqtag;
1461                 const struct pppoe_tag  *tag;
1462                 struct mbuf     *m0;
1463                 const struct pppoe_hdr  *ph;
1464                 negp            neg = sp->neg;
1465                 uint16_t        session;
1466                 uint16_t        length;
1467                 uint8_t         code;
1468
1469                 /*
1470                  * A PADI packet is being returned by the application
1471                  * that has set up this hook. This indicates that it
1472                  * wants us to offer service.
1473                  */
1474                 if (m->m_len < sizeof(*wh)) {
1475                         m = m_pullup(m, sizeof(*wh));
1476                         if (m == NULL)
1477                                 LEAVE(ENOBUFS);
1478                 }
1479                 wh = mtod(m, struct pppoe_full_hdr *);
1480                 ph = &wh->ph;
1481                 session = ntohs(wh->ph.sid);
1482                 length = ntohs(wh->ph.length);
1483                 code = wh->ph.code;
1484                 /* Use peers mode in session. */
1485                 neg->pkt->pkt_header.eh.ether_type = wh->eh.ether_type;
1486                 if (code != PADI_CODE)
1487                         LEAVE(EINVAL);
1488                 ng_uncallout(&neg->handle, node);
1489
1490                 /*
1491                  * This is the first time we hear
1492                  * from the client, so note it's
1493                  * unicast address, replacing the
1494                  * broadcast address.
1495                  */
1496                 bcopy(wh->eh.ether_shost,
1497                         neg->pkt->pkt_header.eh.ether_dhost,
1498                         ETHER_ADDR_LEN);
1499                 sp->state = PPPOE_SOFFER;
1500                 neg->timeout = 0;
1501                 neg->pkt->pkt_header.ph.code = PADO_CODE;
1502
1503                 /*
1504                  * Start working out the tags to respond with.
1505                  */
1506                 uniqtag.hdr.tag_type = PTT_AC_COOKIE;
1507                 uniqtag.hdr.tag_len = htons((u_int16_t)sizeof(sp));
1508                 uniqtag.data.pointer = sp;
1509                 init_tags(sp);
1510                 insert_tag(sp, &neg->ac_name.hdr); /* AC_NAME */
1511                 if ((tag = get_tag(ph, PTT_SRV_NAME)))
1512                         insert_tag(sp, tag);      /* return service */
1513                 /*
1514                  * If we have a NULL service request
1515                  * and have an extra service defined in this hook,
1516                  * then also add a tag for the extra service.
1517                  * XXX this is a hack. eventually we should be able
1518                  * to support advertising many services, not just one
1519                  */
1520                 if (((tag == NULL) || (tag->tag_len == 0)) &&
1521                     (neg->service.hdr.tag_len != 0)) {
1522                         insert_tag(sp, &neg->service.hdr); /* SERVICE */
1523                 }
1524                 if ((tag = get_tag(ph, PTT_HOST_UNIQ)))
1525                         insert_tag(sp, tag); /* returned hostunique */
1526                 insert_tag(sp, &uniqtag.hdr);
1527                 scan_tags(sp, ph);
1528                 make_packet(sp);
1529                 /*
1530                  * Send the offer but if they don't respond
1531                  * in PPPOE_OFFER_TIMEOUT seconds, forget about it.
1532                  */
1533                 ng_callout(&neg->handle, node, hook, PPPOE_OFFER_TIMEOUT * hz,
1534                     pppoe_ticker, NULL, 0);
1535                 m0 = m_copypacket(sp->neg->m, M_NOWAIT);
1536                 NG_FWD_NEW_DATA(error, item, privp->ethernet_hook, m0);
1537                 privp->packets_out++;
1538                 break;
1539                 }
1540
1541         /*
1542          * Packets coming from the hook make no sense
1543          * to sessions in the rest of states. Throw them away.
1544          */
1545         default:
1546                 LEAVE(ENETUNREACH);
1547         }
1548 quit:
1549         if (item)
1550                 NG_FREE_ITEM(item);
1551         NG_FREE_M(m);
1552         return (error);
1553 }
1554
1555 /*
1556  * Receive data from ether and do something with it.
1557  */
1558 static int
1559 ng_pppoe_rcvdata_ether(hook_p hook, item_p item)
1560 {
1561         node_p                  node = NG_HOOK_NODE(hook);
1562         const priv_p            privp = NG_NODE_PRIVATE(node);
1563         sessp                   sp;
1564         const struct pppoe_tag  *utag = NULL, *tag = NULL;
1565         const struct pppoe_tag  sntag = { PTT_SRV_NAME, 0 };
1566         const struct pppoe_full_hdr *wh;
1567         const struct pppoe_hdr  *ph;
1568         negp                    neg = NULL;
1569         struct mbuf             *m;
1570         hook_p                  sendhook;
1571         int                     error = 0;
1572         uint16_t                session;
1573         uint16_t                length;
1574         uint8_t                 code;
1575         struct  mbuf            *m0;
1576
1577         CTR6(KTR_NET, "%20s: node [%x] (%p) received %p on \"%s\" (%p)",
1578             __func__, node->nd_ID, node, item, hook->hk_name, hook);
1579
1580         NGI_GET_M(item, m);
1581         /*
1582          * Dig out various fields from the packet.
1583          * Use them to decide where to send it.
1584          */
1585         privp->packets_in++;
1586         if( m->m_len < sizeof(*wh)) {
1587                 m = m_pullup(m, sizeof(*wh)); /* Checks length */
1588                 if (m == NULL) {
1589                         log(LOG_NOTICE, "ng_pppoe[%x]: couldn't "
1590                             "m_pullup(wh)\n", node->nd_ID);
1591                         LEAVE(ENOBUFS);
1592                 }
1593         }
1594         wh = mtod(m, struct pppoe_full_hdr *);
1595         length = ntohs(wh->ph.length);
1596         switch(wh->eh.ether_type) {
1597         case    ETHERTYPE_PPPOE_3COM_DISC: /* fall through */
1598         case    ETHERTYPE_PPPOE_DISC:
1599                 /*
1600                  * We need to try to make sure that the tag area
1601                  * is contiguous, or we could wander off the end
1602                  * of a buffer and make a mess.
1603                  * (Linux wouldn't have this problem).
1604                  */
1605                 if (m->m_pkthdr.len <= MHLEN) {
1606                         if( m->m_len < m->m_pkthdr.len) {
1607                                 m = m_pullup(m, m->m_pkthdr.len);
1608                                 if (m == NULL) {
1609                                         log(LOG_NOTICE, "ng_pppoe[%x]: "
1610                                             "couldn't m_pullup(pkthdr)\n",
1611                                             node->nd_ID);
1612                                         LEAVE(ENOBUFS);
1613                                 }
1614                         }
1615                 }
1616                 if (m->m_len != m->m_pkthdr.len) {
1617                         /*
1618                          * It's not all in one piece.
1619                          * We need to do extra work.
1620                          * Put it into a cluster.
1621                          */
1622                         struct mbuf *n;
1623                         n = m_dup(m, M_NOWAIT);
1624                         m_freem(m);
1625                         m = n;
1626                         if (m) {
1627                                 /* just check we got a cluster */
1628                                 if (m->m_len != m->m_pkthdr.len) {
1629                                         m_freem(m);
1630                                         m = NULL;
1631                                 }
1632                         }
1633                         if (m == NULL) {
1634                                 log(LOG_NOTICE, "ng_pppoe[%x]: packet "
1635                                     "fragmented\n", node->nd_ID);
1636                                 LEAVE(EMSGSIZE);
1637                         }
1638                 }
1639                 wh = mtod(m, struct pppoe_full_hdr *);
1640                 length = ntohs(wh->ph.length);
1641                 ph = &wh->ph;
1642                 session = ntohs(wh->ph.sid);
1643                 code = wh->ph.code;
1644
1645                 switch(code) {
1646                 case    PADI_CODE:
1647                         /*
1648                          * We are a server:
1649                          * Look for a hook with the required service and send
1650                          * the ENTIRE packet up there. It should come back to
1651                          * a new hook in PRIMED state. Look there for further
1652                          * processing.
1653                          */
1654                         tag = get_tag(ph, PTT_SRV_NAME);
1655                         if (tag == NULL)
1656                                 tag = &sntag;
1657
1658                         /*
1659                          * First, try to match Service-Name against our
1660                          * listening hooks. If no success and we are in D-Link
1661                          * compat mode and Service-Name is empty, then we
1662                          * broadcast the PADI to all listening hooks.
1663                          */
1664                         sendhook = pppoe_match_svc(node, tag);
1665                         if (sendhook != NULL)
1666                                 NG_FWD_NEW_DATA(error, item, sendhook, m);
1667                         else if (privp->flags & COMPAT_DLINK &&
1668                                  ntohs(tag->tag_len) == 0)
1669                                 error = pppoe_broadcast_padi(node, m);
1670                         else
1671                                 error = ENETUNREACH;
1672                         break;
1673                 case    PADO_CODE:
1674                         /*
1675                          * We are a client:
1676                          * Use the host_uniq tag to find the hook this is in
1677                          * response to. Received #2, now send #3
1678                          * For now simply accept the first we receive.
1679                          */
1680                         utag = get_tag(ph, PTT_HOST_UNIQ);
1681                         if (utag == NULL) {
1682                                 log(LOG_NOTICE, "ng_pppoe[%x]: no host "
1683                                     "unique field\n", node->nd_ID);
1684                                 LEAVE(ENETUNREACH);
1685                         }
1686
1687                         sendhook = pppoe_finduniq(node, utag);
1688                         if (sendhook == NULL) {
1689                                 log(LOG_NOTICE, "ng_pppoe[%x]: no "
1690                                     "matching session\n", node->nd_ID);
1691                                 LEAVE(ENETUNREACH);
1692                         }
1693
1694                         /*
1695                          * Check the session is in the right state.
1696                          * It needs to be in PPPOE_SINIT.
1697                          */
1698                         sp = NG_HOOK_PRIVATE(sendhook);
1699                         if (sp->state == PPPOE_SREQ ||
1700                             sp->state == PPPOE_CONNECTED) {
1701                                 break;  /* Multiple PADO is OK. */
1702                         }
1703                         if (sp->state != PPPOE_SINIT) {
1704                                 log(LOG_NOTICE, "ng_pppoe[%x]: session "
1705                                     "in wrong state\n", node->nd_ID);
1706                                 LEAVE(ENETUNREACH);
1707                         }
1708                         neg = sp->neg;
1709                         /* If requested specific AC-name, check it. */
1710                         if (neg->ac_name_len) {
1711                                 tag = get_tag(ph, PTT_AC_NAME);
1712                                 if (!tag) {
1713                                         /* No PTT_AC_NAME in PADO */
1714                                         break;
1715                                 }
1716                                 if (neg->ac_name_len != htons(tag->tag_len) ||
1717                                     strncmp(neg->ac_name.data,
1718                                     (const char *)(tag + 1),
1719                                     neg->ac_name_len) != 0) {
1720                                         break;
1721                                 }
1722                         }
1723                         sp->state = PPPOE_SREQ;
1724                         ng_uncallout(&neg->handle, node);
1725
1726                         /*
1727                          * This is the first time we hear
1728                          * from the server, so note it's
1729                          * unicast address, replacing the
1730                          * broadcast address .
1731                          */
1732                         bcopy(wh->eh.ether_shost,
1733                                 neg->pkt->pkt_header.eh.ether_dhost,
1734                                 ETHER_ADDR_LEN);
1735                         neg->timeout = 0;
1736                         neg->pkt->pkt_header.ph.code = PADR_CODE;
1737                         init_tags(sp);
1738                         insert_tag(sp, utag);           /* Host Unique */
1739                         if ((tag = get_tag(ph, PTT_AC_COOKIE)))
1740                                 insert_tag(sp, tag);    /* return cookie */
1741                         if ((tag = get_tag(ph, PTT_AC_NAME))) {
1742                                 insert_tag(sp, tag);    /* return it */
1743                                 send_acname(sp, tag);
1744                         }
1745                         if ((tag = get_tag(ph, PTT_MAX_PAYL)) &&
1746                             (privp->max_payload.data != 0))
1747                                 insert_tag(sp, tag);    /* return it */
1748                         insert_tag(sp, &neg->service.hdr); /* Service */
1749                         scan_tags(sp, ph);
1750                         make_packet(sp);
1751                         sp->state = PPPOE_SREQ;
1752                         ng_callout(&neg->handle, node, sp->hook,
1753                             PPPOE_INITIAL_TIMEOUT * hz,
1754                             pppoe_ticker, NULL, 0);
1755                         neg->timeout = PPPOE_INITIAL_TIMEOUT * 2;
1756                         m0 = m_copypacket(neg->m, M_NOWAIT);
1757                         NG_FWD_NEW_DATA(error, item, privp->ethernet_hook, m0);
1758                         break;
1759                 case    PADR_CODE:
1760                         /*
1761                          * We are a server:
1762                          * Use the ac_cookie tag to find the
1763                          * hook this is in response to.
1764                          */
1765                         utag = get_tag(ph, PTT_AC_COOKIE);
1766                         if ((utag == NULL) ||
1767                             (ntohs(utag->tag_len) != sizeof(sp))) {
1768                                 LEAVE(ENETUNREACH);
1769                         }
1770
1771                         sendhook = pppoe_findcookie(node, utag);
1772                         if (sendhook == NULL)
1773                                 LEAVE(ENETUNREACH);
1774
1775                         /*
1776                          * Check the session is in the right state.
1777                          * It needs to be in PPPOE_SOFFER or PPPOE_NEWCONNECTED.
1778                          * If the latter, then this is a retry by the client,
1779                          * so be nice, and resend.
1780                          */
1781                         sp = NG_HOOK_PRIVATE(sendhook);
1782                         if (sp->state == PPPOE_NEWCONNECTED) {
1783                                 /*
1784                                  * Whoa! drop back to resend that PADS packet.
1785                                  * We should still have a copy of it.
1786                                  */
1787                                 sp->state = PPPOE_SOFFER;
1788                         } else if (sp->state != PPPOE_SOFFER)
1789                                 LEAVE (ENETUNREACH);
1790                         neg = sp->neg;
1791                         ng_uncallout(&neg->handle, node);
1792                         neg->pkt->pkt_header.ph.code = PADS_CODE;
1793                         if (sp->Session_ID == 0) {
1794                                 neg->pkt->pkt_header.ph.sid =
1795                                     htons(pppoe_getnewsession(sp));
1796                         }
1797                         send_sessionid(sp);
1798                         neg->timeout = 0;
1799                         /*
1800                          * start working out the tags to respond with.
1801                          */
1802                         init_tags(sp);
1803                         insert_tag(sp, &neg->ac_name.hdr); /* AC_NAME */
1804                         if ((tag = get_tag(ph, PTT_SRV_NAME)))
1805                                 insert_tag(sp, tag);/* return service */
1806                         if ((tag = get_tag(ph, PTT_HOST_UNIQ)))
1807                                 insert_tag(sp, tag); /* return it */
1808                         insert_tag(sp, utag);   /* ac_cookie */
1809                         scan_tags(sp, ph);
1810                         make_packet(sp);
1811                         sp->state = PPPOE_NEWCONNECTED;
1812
1813                         /* Send the PADS without a timeout - we're now connected. */
1814                         m0 = m_copypacket(sp->neg->m, M_NOWAIT);
1815                         NG_FWD_NEW_DATA(error, item, privp->ethernet_hook, m0);
1816
1817                         /*
1818                          * Having sent the last Negotiation header,
1819                          * Set up the stored packet header to be correct for
1820                          * the actual session. But keep the negotialtion stuff
1821                          * around in case we need to resend this last packet.
1822                          * We'll discard it when we move from NEWCONNECTED
1823                          * to CONNECTED
1824                          */
1825                         sp->pkt_hdr = neg->pkt->pkt_header;
1826                         /* Configure ethertype depending on what
1827                          * ethertype was used at discovery phase */
1828                         if (sp->pkt_hdr.eh.ether_type ==
1829                             ETHERTYPE_PPPOE_3COM_DISC)
1830                                 sp->pkt_hdr.eh.ether_type
1831                                         = ETHERTYPE_PPPOE_3COM_SESS;
1832                         else
1833                                 sp->pkt_hdr.eh.ether_type
1834                                         = ETHERTYPE_PPPOE_SESS;
1835                         sp->pkt_hdr.ph.code = 0;
1836                         pppoe_send_event(sp, NGM_PPPOE_SUCCESS);
1837                         break;
1838                 case    PADS_CODE:
1839                         /*
1840                          * We are a client:
1841                          * Use the host_uniq tag to find the hook this is in
1842                          * response to. Take the session ID and store it away.
1843                          * Also make sure the pre-made header is correct and
1844                          * set us into Session mode.
1845                          */
1846                         utag = get_tag(ph, PTT_HOST_UNIQ);
1847                         if (utag == NULL) {
1848                                 LEAVE (ENETUNREACH);
1849                         }
1850                         sendhook = pppoe_finduniq(node, utag);
1851                         if (sendhook == NULL)
1852                                 LEAVE(ENETUNREACH);
1853
1854                         /*
1855                          * Check the session is in the right state.
1856                          * It needs to be in PPPOE_SREQ.
1857                          */
1858                         sp = NG_HOOK_PRIVATE(sendhook);
1859                         if (sp->state != PPPOE_SREQ)
1860                                 LEAVE(ENETUNREACH);
1861                         neg = sp->neg;
1862                         ng_uncallout(&neg->handle, node);
1863                         neg->pkt->pkt_header.ph.sid = wh->ph.sid;
1864                         sp->Session_ID = ntohs(wh->ph.sid);
1865                         pppoe_addsession(sp);
1866                         send_sessionid(sp);
1867                         neg->timeout = 0;
1868                         sp->state = PPPOE_CONNECTED;
1869                         /*
1870                          * Now we have gone to Connected mode,
1871                          * Free all resources needed for negotiation.
1872                          * Keep a copy of the header we will be using.
1873                          */
1874                         sp->pkt_hdr = neg->pkt->pkt_header;
1875                         if (privp->flags & COMPAT_3COM)
1876                                 sp->pkt_hdr.eh.ether_type
1877                                         = ETHERTYPE_PPPOE_3COM_SESS;
1878                         else
1879                                 sp->pkt_hdr.eh.ether_type
1880                                         = ETHERTYPE_PPPOE_SESS;
1881                         sp->pkt_hdr.ph.code = 0;
1882                         m_freem(neg->m);
1883                         free(sp->neg, M_NETGRAPH_PPPOE);
1884                         sp->neg = NULL;
1885                         if ((tag = get_tag(ph, PTT_MAX_PAYL)) &&
1886                             (privp->max_payload.data != 0))
1887                                 send_maxp(sp, tag);
1888                         pppoe_send_event(sp, NGM_PPPOE_SUCCESS);
1889                         break;
1890                 case    PADT_CODE:
1891                         /*
1892                          * Find matching peer/session combination.
1893                          */
1894                         sp = pppoe_findsession(privp, wh);
1895                         if (sp == NULL)
1896                                 LEAVE(ENETUNREACH);
1897                         /* Disconnect that hook. */
1898                         ng_rmhook_self(sp->hook);
1899                         break;
1900                 case    PADM_CODE:
1901                         /*
1902                          * We are a client:
1903                          * find matching peer/session combination.
1904                          */
1905                         sp = pppoe_findsession(privp, wh);
1906                         if (sp == NULL)
1907                                 LEAVE (ENETUNREACH);
1908                         if ((tag = get_tag(ph, PTT_HURL)))
1909                                 send_hurl(sp, tag);
1910                         if ((tag = get_tag(ph, PTT_MOTM)))
1911                                 send_motm(sp, tag);
1912                         break;
1913                 default:
1914                         LEAVE(EPFNOSUPPORT);
1915                 }
1916                 break;
1917         case    ETHERTYPE_PPPOE_3COM_SESS:
1918         case    ETHERTYPE_PPPOE_SESS:
1919                 /*
1920                  * Find matching peer/session combination.
1921                  */
1922                 sp = pppoe_findsession(privp, wh);
1923                 if (sp == NULL)
1924                         LEAVE (ENETUNREACH);
1925                 m_adj(m, sizeof(*wh));
1926
1927                 /* If packet too short, dump it. */
1928                 if (m->m_pkthdr.len < length)
1929                         LEAVE(EMSGSIZE);
1930                 /* Also need to trim excess at the end */
1931                 if (m->m_pkthdr.len > length) {
1932                         m_adj(m, -((int)(m->m_pkthdr.len - length)));
1933                 }
1934                 if ( sp->state != PPPOE_CONNECTED) {
1935                         if (sp->state == PPPOE_NEWCONNECTED) {
1936                                 sp->state = PPPOE_CONNECTED;
1937                                 /*
1938                                  * Now we have gone to Connected mode,
1939                                  * Free all resources needed for negotiation.
1940                                  * Be paranoid about whether there may be
1941                                  * a timeout.
1942                                  */
1943                                 m_freem(sp->neg->m);
1944                                 ng_uncallout(&sp->neg->handle, node);
1945                                 free(sp->neg, M_NETGRAPH_PPPOE);
1946                                 sp->neg = NULL;
1947                         } else {
1948                                 LEAVE (ENETUNREACH);
1949                         }
1950                 }
1951                 NG_FWD_NEW_DATA(error, item, sp->hook, m);
1952                 break;
1953         default:
1954                 LEAVE(EPFNOSUPPORT);
1955         }
1956 quit:
1957         if (item)
1958                 NG_FREE_ITEM(item);
1959         NG_FREE_M(m);
1960         return (error);
1961 }
1962
1963 /*
1964  * Receive data from debug hook and bypass it to ether.
1965  */
1966 static int
1967 ng_pppoe_rcvdata_debug(hook_p hook, item_p item)
1968 {
1969         node_p          node = NG_HOOK_NODE(hook);
1970         const priv_p    privp = NG_NODE_PRIVATE(node);
1971         int             error;
1972
1973         CTR6(KTR_NET, "%20s: node [%x] (%p) received %p on \"%s\" (%p)",
1974             __func__, node->nd_ID, node, item, hook->hk_name, hook);
1975
1976         NG_FWD_ITEM_HOOK(error, item, privp->ethernet_hook);
1977         privp->packets_out++;
1978         return (error);
1979 }
1980
1981 /*
1982  * Do local shutdown processing..
1983  * If we are a persistent device, we might refuse to go away, and
1984  * we'd only remove our links and reset ourself.
1985  */
1986 static int
1987 ng_pppoe_shutdown(node_p node)
1988 {
1989         const priv_p privp = NG_NODE_PRIVATE(node);
1990         int     i;
1991
1992         for (i = 0; i < SESSHASHSIZE; i++)
1993             mtx_destroy(&privp->sesshash[i].mtx);
1994         NG_NODE_SET_PRIVATE(node, NULL);
1995         NG_NODE_UNREF(privp->node);
1996         free(privp, M_NETGRAPH_PPPOE);
1997         return (0);
1998 }
1999
2000 /*
2001  * Hook disconnection
2002  *
2003  * Clean up all dangling links and information about the session/hook.
2004  * For this type, removal of the last link destroys the node.
2005  */
2006 static int
2007 ng_pppoe_disconnect(hook_p hook)
2008 {
2009         node_p node = NG_HOOK_NODE(hook);
2010         priv_p privp = NG_NODE_PRIVATE(node);
2011         sessp   sp;
2012
2013         if (hook == privp->debug_hook) {
2014                 privp->debug_hook = NULL;
2015         } else if (hook == privp->ethernet_hook) {
2016                 privp->ethernet_hook = NULL;
2017                 if (NG_NODE_IS_VALID(node))
2018                         ng_rmnode_self(node);
2019         } else {
2020                 sp = NG_HOOK_PRIVATE(hook);
2021                 if (sp->state != PPPOE_SNONE ) {
2022                         pppoe_send_event(sp, NGM_PPPOE_CLOSE);
2023                 }
2024                 /*
2025                  * According to the spec, if we are connected,
2026                  * we should send a DISC packet if we are shutting down
2027                  * a session.
2028                  */
2029                 if ((privp->ethernet_hook)
2030                 && ((sp->state == PPPOE_CONNECTED)
2031                  || (sp->state == PPPOE_NEWCONNECTED))) {
2032                         struct mbuf *m;
2033
2034                         /* Generate a packet of that type. */
2035                         m = m_gethdr(M_NOWAIT, MT_DATA);
2036                         if (m == NULL)
2037                                 log(LOG_NOTICE, "ng_pppoe[%x]: session out of "
2038                                     "mbufs\n", node->nd_ID);
2039                         else {
2040                                 struct pppoe_full_hdr *wh;
2041                                 struct pppoe_tag *tag;
2042                                 int     msglen = strlen(SIGNOFF);
2043                                 int     error = 0;
2044
2045                                 wh = mtod(m, struct pppoe_full_hdr *);
2046                                 bcopy(&sp->pkt_hdr, wh, sizeof(*wh));
2047
2048                                 /* Revert the stored header to DISC/PADT mode. */
2049                                 wh->ph.code = PADT_CODE;
2050                                 /*
2051                                  * Configure ethertype depending on what
2052                                  * was used during sessions stage.
2053                                  */
2054                                 if (wh->eh.ether_type ==
2055                                     ETHERTYPE_PPPOE_3COM_SESS)
2056                                         wh->eh.ether_type = ETHERTYPE_PPPOE_3COM_DISC;
2057                                 else
2058                                         wh->eh.ether_type = ETHERTYPE_PPPOE_DISC;
2059                                 /*
2060                                  * Add a General error message and adjust
2061                                  * sizes.
2062                                  */
2063                                 tag = (void *)(&wh->ph + 1);
2064                                 tag->tag_type = PTT_GEN_ERR;
2065                                 tag->tag_len = htons((u_int16_t)msglen);
2066                                 strncpy((char *)(tag + 1), SIGNOFF, msglen);
2067                                 m->m_pkthdr.len = m->m_len = sizeof(*wh) + sizeof(*tag) +
2068                                     msglen;
2069                                 wh->ph.length = htons(sizeof(*tag) + msglen);
2070                                 NG_SEND_DATA_ONLY(error,
2071                                         privp->ethernet_hook, m);
2072                         }
2073                 }
2074                 if (sp->state == PPPOE_LISTENING)
2075                         LIST_REMOVE(sp, sessions);
2076                 else if (sp->Session_ID)
2077                         pppoe_delsession(sp);
2078                 /*
2079                  * As long as we have somewhere to store the timeout handle,
2080                  * we may have a timeout pending.. get rid of it.
2081                  */
2082                 if (sp->neg) {
2083                         ng_uncallout(&sp->neg->handle, node);
2084                         if (sp->neg->m)
2085                                 m_freem(sp->neg->m);
2086                         free(sp->neg, M_NETGRAPH_PPPOE);
2087                 }
2088                 free(sp, M_NETGRAPH_PPPOE);
2089                 NG_HOOK_SET_PRIVATE(hook, NULL);
2090         }
2091         if ((NG_NODE_NUMHOOKS(node) == 0) &&
2092             (NG_NODE_IS_VALID(node)))
2093                 ng_rmnode_self(node);
2094         return (0);
2095 }
2096
2097 /*
2098  * Timeouts come here.
2099  */
2100 static void
2101 pppoe_ticker(node_p node, hook_p hook, void *arg1, int arg2)
2102 {
2103         priv_p privp = NG_NODE_PRIVATE(NG_HOOK_NODE(hook));
2104         sessp   sp = NG_HOOK_PRIVATE(hook);
2105         negp    neg = sp->neg;
2106         struct mbuf *m0 = NULL;
2107         int     error = 0;
2108
2109         CTR6(KTR_NET, "%20s: node [%x] (%p) hook \"%s\" (%p) session %d",
2110             __func__, node->nd_ID, node, hook->hk_name, hook, sp->Session_ID);
2111         switch(sp->state) {
2112                 /*
2113                  * Resend the last packet, using an exponential backoff.
2114                  * After a period of time, stop growing the backoff,
2115                  * And either leave it, or revert to the start.
2116                  */
2117         case    PPPOE_SINIT:
2118         case    PPPOE_SREQ:
2119                 /* Timeouts on these produce resends. */
2120                 m0 = m_copypacket(sp->neg->m, M_NOWAIT);
2121                 NG_SEND_DATA_ONLY( error, privp->ethernet_hook, m0);
2122                 ng_callout(&neg->handle, node, hook, neg->timeout * hz,
2123                     pppoe_ticker, NULL, 0);
2124                 if ((neg->timeout <<= 1) > PPPOE_TIMEOUT_LIMIT) {
2125                         if (sp->state == PPPOE_SREQ) {
2126                                 /* Revert to SINIT mode. */
2127                                 pppoe_start(sp);
2128                         } else {
2129                                 neg->timeout = PPPOE_TIMEOUT_LIMIT;
2130                         }
2131                 }
2132                 break;
2133         case    PPPOE_PRIMED:
2134         case    PPPOE_SOFFER:
2135                 /* A timeout on these says "give up" */
2136                 ng_rmhook_self(hook);
2137                 break;
2138         default:
2139                 /* Timeouts have no meaning in other states. */
2140                 log(LOG_NOTICE, "ng_pppoe[%x]: unexpected timeout\n",
2141                     node->nd_ID);
2142         }
2143 }
2144
2145 /*
2146  * Parse an incoming packet to see if any tags should be copied to the
2147  * output packet. Don't do any tags that have been handled in the main
2148  * state machine.
2149  */
2150 static const struct pppoe_tag*
2151 scan_tags(sessp sp, const struct pppoe_hdr* ph)
2152 {
2153         const char *const end = (const char *)next_tag(ph);
2154         const char *ptn;
2155         const struct pppoe_tag *pt = (const void *)(ph + 1);
2156
2157         /*
2158          * Keep processing tags while a tag header will still fit.
2159          */
2160         CTR2(KTR_NET, "%20s: called %d", __func__, sp->Session_ID);
2161
2162         while((const char*)(pt + 1) <= end) {
2163                 /*
2164                  * If the tag data would go past the end of the packet, abort.
2165                  */
2166                 ptn = (((const char *)(pt + 1)) + ntohs(pt->tag_len));
2167                 if(ptn > end)
2168                         return NULL;
2169
2170                 switch (pt->tag_type) {
2171                 case    PTT_RELAY_SID:
2172                         insert_tag(sp, pt);
2173                         break;
2174                 case    PTT_EOL:
2175                         return NULL;
2176                 case    PTT_SRV_NAME:
2177                 case    PTT_AC_NAME:
2178                 case    PTT_HOST_UNIQ:
2179                 case    PTT_AC_COOKIE:
2180                 case    PTT_VENDOR:
2181                 case    PTT_SRV_ERR:
2182                 case    PTT_SYS_ERR:
2183                 case    PTT_GEN_ERR:
2184                 case    PTT_MAX_PAYL:
2185                 case    PTT_HURL:
2186                 case    PTT_MOTM:
2187                         break;
2188                 }
2189                 pt = (const struct pppoe_tag*)ptn;
2190         }
2191         return NULL;
2192 }
2193
2194 static  int
2195 pppoe_send_event(sessp sp, enum cmd cmdid)
2196 {
2197         int error;
2198         struct ng_mesg *msg;
2199         struct ngpppoe_sts *sts;
2200
2201         CTR2(KTR_NET, "%20s: called %d", __func__, sp->Session_ID);
2202
2203         NG_MKMESSAGE(msg, NGM_PPPOE_COOKIE, cmdid,
2204                         sizeof(struct ngpppoe_sts), M_NOWAIT);
2205         if (msg == NULL)
2206                 return (ENOMEM);
2207         sts = (struct ngpppoe_sts *)msg->data;
2208         strncpy(sts->hook, NG_HOOK_NAME(sp->hook), NG_HOOKSIZ);
2209         NG_SEND_MSG_ID(error, NG_HOOK_NODE(sp->hook), msg, sp->creator, 0);
2210         return (error);
2211 }