The Design and Implementation of the FreeBSD Operating System, Second Edition
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sys/netgraph/ng_pppoe.c

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    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: releng/12.0/sys/netgraph/ng_pppoe.c 329279 2018-02-14 21:17:44Z eugen $
   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/syslog.h>
   52 #include <net/ethernet.h>
   53 
   54 #include <netgraph/ng_message.h>
   55 #include <netgraph/netgraph.h>
   56 #include <netgraph/ng_parse.h>
   57 #include <netgraph/ng_pppoe.h>
   58 #include <netgraph/ng_ether.h>
   59 
   60 #ifdef NG_SEPARATE_MALLOC
   61 static MALLOC_DEFINE(M_NETGRAPH_PPPOE, "netgraph_pppoe", "netgraph pppoe node");
   62 #else
   63 #define M_NETGRAPH_PPPOE M_NETGRAPH
   64 #endif
   65 
   66 #define SIGNOFF "session closed"
   67 
   68 /*
   69  * This section contains the netgraph method declarations for the
   70  * pppoe node. These methods define the netgraph pppoe 'type'.
   71  */
   72 
   73 static ng_constructor_t ng_pppoe_constructor;
   74 static ng_rcvmsg_t      ng_pppoe_rcvmsg;
   75 static ng_shutdown_t    ng_pppoe_shutdown;
   76 static ng_newhook_t     ng_pppoe_newhook;
   77 static ng_connect_t     ng_pppoe_connect;
   78 static ng_rcvdata_t     ng_pppoe_rcvdata;
   79 static ng_rcvdata_t     ng_pppoe_rcvdata_ether;
   80 static ng_rcvdata_t     ng_pppoe_rcvdata_debug;
   81 static ng_disconnect_t  ng_pppoe_disconnect;
   82 
   83 /* Parse type for struct ngpppoe_init_data */
   84 static const struct ng_parse_struct_field ngpppoe_init_data_type_fields[]
   85         = NG_PPPOE_INIT_DATA_TYPE_INFO;
   86 static const struct ng_parse_type ngpppoe_init_data_state_type = {
   87         &ng_parse_struct_type,
   88         &ngpppoe_init_data_type_fields
   89 };
   90 
   91 /* Parse type for struct ngpppoe_sts */
   92 static const struct ng_parse_struct_field ng_pppoe_sts_type_fields[]
   93         = NG_PPPOE_STS_TYPE_INFO;
   94 static const struct ng_parse_type ng_pppoe_sts_state_type = {
   95         &ng_parse_struct_type,
   96         &ng_pppoe_sts_type_fields
   97 };
   98 
   99 /* List of commands and how to convert arguments to/from ASCII */
  100 static const struct ng_cmdlist ng_pppoe_cmds[] = {
  101         {
  102           NGM_PPPOE_COOKIE,
  103           NGM_PPPOE_CONNECT,
  104           "pppoe_connect",
  105           &ngpppoe_init_data_state_type,
  106           NULL
  107         },
  108         {
  109           NGM_PPPOE_COOKIE,
  110           NGM_PPPOE_LISTEN,
  111           "pppoe_listen",
  112           &ngpppoe_init_data_state_type,
  113           NULL
  114         },
  115         {
  116           NGM_PPPOE_COOKIE,
  117           NGM_PPPOE_OFFER,
  118           "pppoe_offer",
  119           &ngpppoe_init_data_state_type,
  120           NULL
  121         },
  122         {
  123           NGM_PPPOE_COOKIE,
  124           NGM_PPPOE_SERVICE,
  125           "pppoe_service",
  126           &ngpppoe_init_data_state_type,
  127           NULL
  128         },
  129         {
  130           NGM_PPPOE_COOKIE,
  131           NGM_PPPOE_SUCCESS,
  132           "pppoe_success",
  133           &ng_pppoe_sts_state_type,
  134           NULL
  135         },
  136         {
  137           NGM_PPPOE_COOKIE,
  138           NGM_PPPOE_FAIL,
  139           "pppoe_fail",
  140           &ng_pppoe_sts_state_type,
  141           NULL
  142         },
  143         {
  144           NGM_PPPOE_COOKIE,
  145           NGM_PPPOE_CLOSE,
  146           "pppoe_close",
  147           &ng_pppoe_sts_state_type,
  148           NULL
  149         },
  150         {
  151           NGM_PPPOE_COOKIE,
  152           NGM_PPPOE_SETMODE,
  153           "pppoe_setmode",
  154           &ng_parse_string_type,
  155           NULL
  156         },
  157         {
  158           NGM_PPPOE_COOKIE,
  159           NGM_PPPOE_GETMODE,
  160           "pppoe_getmode",
  161           NULL,
  162           &ng_parse_string_type
  163         },
  164         {
  165           NGM_PPPOE_COOKIE,
  166           NGM_PPPOE_SETENADDR,
  167           "setenaddr",
  168           &ng_parse_enaddr_type,
  169           NULL
  170         },
  171         {
  172           NGM_PPPOE_COOKIE,
  173           NGM_PPPOE_SETMAXP,
  174           "setmaxp",
  175           &ng_parse_uint16_type,
  176           NULL
  177         },
  178         {
  179           NGM_PPPOE_COOKIE,
  180           NGM_PPPOE_SEND_HURL,
  181           "send_hurl",
  182           &ngpppoe_init_data_state_type,
  183           NULL
  184         },
  185         {
  186           NGM_PPPOE_COOKIE,
  187           NGM_PPPOE_SEND_MOTM,
  188           "send_motm",
  189           &ngpppoe_init_data_state_type,
  190           NULL
  191         },
  192         { 0 }
  193 };
  194 
  195 /* Netgraph node type descriptor */
  196 static struct ng_type typestruct = {
  197         .version =      NG_ABI_VERSION,
  198         .name =         NG_PPPOE_NODE_TYPE,
  199         .constructor =  ng_pppoe_constructor,
  200         .rcvmsg =       ng_pppoe_rcvmsg,
  201         .shutdown =     ng_pppoe_shutdown,
  202         .newhook =      ng_pppoe_newhook,
  203         .connect =      ng_pppoe_connect,
  204         .rcvdata =      ng_pppoe_rcvdata,
  205         .disconnect =   ng_pppoe_disconnect,
  206         .cmdlist =      ng_pppoe_cmds,
  207 };
  208 NETGRAPH_INIT(pppoe, &typestruct);
  209 
  210 /*
  211  * States for the session state machine.
  212  * These have no meaning if there is no hook attached yet.
  213  */
  214 enum state {
  215     PPPOE_SNONE=0,      /* [both] Initial state */
  216     PPPOE_LISTENING,    /* [Daemon] Listening for discover initiation pkt */
  217     PPPOE_SINIT,        /* [Client] Sent discovery initiation */
  218     PPPOE_PRIMED,       /* [Server] Awaiting PADI from daemon */
  219     PPPOE_SOFFER,       /* [Server] Sent offer message  (got PADI)*/
  220     PPPOE_SREQ,         /* [Client] Sent a Request */
  221     PPPOE_NEWCONNECTED, /* [Server] Connection established, No data received */
  222     PPPOE_CONNECTED,    /* [Both] Connection established, Data received */
  223     PPPOE_DEAD          /* [Both] */
  224 };
  225 
  226 #define NUMTAGS 20 /* number of tags we are set up to work with */
  227 
  228 /*
  229  * Information we store for each hook on each node for negotiating the
  230  * session. The mbuf and cluster are freed once negotiation has completed.
  231  * The whole negotiation block is then discarded.
  232  */
  233 
  234 struct sess_neg {
  235         struct mbuf             *m; /* holds cluster with last sent packet */
  236         union   packet          *pkt; /* points within the above cluster */
  237         struct callout          handle;   /* see timeout(9) */
  238         u_int                   timeout; /* 0,1,2,4,8,16 etc. seconds */
  239         u_int                   numtags;
  240         const struct pppoe_tag  *tags[NUMTAGS];
  241         u_int                   service_len;
  242         u_int                   ac_name_len;
  243         u_int                   host_uniq_len;
  244 
  245         struct datatag          service;
  246         struct datatag          ac_name;
  247         struct datatag          host_uniq;
  248 };
  249 typedef struct sess_neg *negp;
  250 
  251 /*
  252  * Session information that is needed after connection.
  253  */
  254 struct sess_con {
  255         hook_p                  hook;
  256         uint16_t                Session_ID;
  257         enum state              state;
  258         ng_ID_t                 creator;        /* who to notify */
  259         struct pppoe_full_hdr   pkt_hdr;        /* used when connected */
  260         negp                    neg;            /* used when negotiating */
  261         LIST_ENTRY(sess_con)    sessions;
  262 };
  263 typedef struct sess_con *sessp;
  264 
  265 #define SESSHASHSIZE    0x0100
  266 #define SESSHASH(x)     (((x) ^ ((x) >> 8)) & (SESSHASHSIZE - 1))
  267 
  268 struct sess_hash_entry {
  269         struct mtx      mtx;
  270         LIST_HEAD(hhead, sess_con) head;
  271 };
  272 
  273 /*
  274  * Information we store for each node
  275  */
  276 struct PPPoE {
  277         node_p          node;           /* back pointer to node */
  278         hook_p          ethernet_hook;
  279         hook_p          debug_hook;
  280         u_int           packets_in;     /* packets in from ethernet */
  281         u_int           packets_out;    /* packets out towards ethernet */
  282         uint32_t        flags;
  283 #define COMPAT_3COM     0x00000001
  284 #define COMPAT_DLINK    0x00000002
  285         struct ether_header     eh;
  286         LIST_HEAD(, sess_con) listeners;
  287         struct sess_hash_entry  sesshash[SESSHASHSIZE];
  288         struct maxptag  max_payload;    /* PPP-Max-Payload (RFC4638) */
  289 };
  290 typedef struct PPPoE *priv_p;
  291 
  292 union uniq {
  293         char bytes[sizeof(void *)];
  294         void *pointer;
  295 };
  296 
  297 #define LEAVE(x) do { error = x; goto quit; } while(0)
  298 static void     pppoe_start(sessp sp);
  299 static void     pppoe_ticker(node_p node, hook_p hook, void *arg1, int arg2);
  300 static const    struct pppoe_tag *scan_tags(sessp sp,
  301                         const struct pppoe_hdr* ph);
  302 static  int     pppoe_send_event(sessp sp, enum cmd cmdid);
  303 
  304 /*************************************************************************
  305  * Some basic utilities  from the Linux version with author's permission.*
  306  * Author:      Michal Ostrowski <mostrows@styx.uwaterloo.ca>            *
  307  ************************************************************************/
  308 
  309 
  310 
  311 /*
  312  * Return the location where the next tag can be put
  313  */
  314 static __inline const struct pppoe_tag*
  315 next_tag(const struct pppoe_hdr* ph)
  316 {
  317         return (const struct pppoe_tag*)(((const char*)(ph + 1))
  318             + ntohs(ph->length));
  319 }
  320 
  321 /*
  322  * Look for a tag of a specific type.
  323  * Don't trust any length the other end says,
  324  * but assume we already sanity checked ph->length.
  325  */
  326 static const struct pppoe_tag*
  327 get_tag(const struct pppoe_hdr* ph, uint16_t idx)
  328 {
  329         const char *const end = (const char *)next_tag(ph);
  330         const struct pppoe_tag *pt = (const void *)(ph + 1);
  331         const char *ptn;
  332 
  333         /*
  334          * Keep processing tags while a tag header will still fit.
  335          */
  336         while((const char*)(pt + 1) <= end) {
  337                 /*
  338                  * If the tag data would go past the end of the packet, abort.
  339                  */
  340                 ptn = (((const char *)(pt + 1)) + ntohs(pt->tag_len));
  341                 if (ptn > end) {
  342                         CTR2(KTR_NET, "%20s: invalid length for tag %d",
  343                             __func__, idx);
  344                         return (NULL);
  345                 }
  346                 if (pt->tag_type == idx) {
  347                         CTR2(KTR_NET, "%20s: found tag %d", __func__, idx);
  348                         return (pt);
  349                 }
  350 
  351                 pt = (const struct pppoe_tag*)ptn;
  352         }
  353 
  354         CTR2(KTR_NET, "%20s: not found tag %d", __func__, idx);
  355         return (NULL);
  356 }
  357 
  358 /**************************************************************************
  359  * Inlines to initialise or add tags to a session's tag list.
  360  **************************************************************************/
  361 /*
  362  * Initialise the session's tag list.
  363  */
  364 static void
  365 init_tags(sessp sp)
  366 {
  367         KASSERT(sp->neg != NULL, ("%s: no neg", __func__));
  368         sp->neg->numtags = 0;
  369 }
  370 
  371 static void
  372 insert_tag(sessp sp, const struct pppoe_tag *tp)
  373 {
  374         negp neg = sp->neg;
  375         int i;
  376 
  377         KASSERT(neg != NULL, ("%s: no neg", __func__));
  378         if ((i = neg->numtags++) < NUMTAGS) {
  379                 neg->tags[i] = tp;
  380         } else {
  381                 log(LOG_NOTICE, "ng_pppoe: asked to add too many tags to "
  382                     "packet\n");
  383                 neg->numtags--;
  384         }
  385 }
  386 
  387 /*
  388  * Make up a packet, using the tags filled out for the session.
  389  *
  390  * Assume that the actual pppoe header and ethernet header
  391  * are filled out externally to this routine.
  392  * Also assume that neg->wh points to the correct
  393  * location at the front of the buffer space.
  394  */
  395 static void
  396 make_packet(sessp sp) {
  397         struct pppoe_full_hdr *wh = &sp->neg->pkt->pkt_header;
  398         const struct pppoe_tag **tag;
  399         char *dp;
  400         int count;
  401         int tlen;
  402         uint16_t length = 0;
  403 
  404         KASSERT((sp->neg != NULL) && (sp->neg->m != NULL),
  405             ("%s: called from wrong state", __func__));
  406         CTR2(KTR_NET, "%20s: called %d", __func__, sp->Session_ID);
  407 
  408         dp = (char *)(&wh->ph + 1);
  409         for (count = 0, tag = sp->neg->tags;
  410             ((count < sp->neg->numtags) && (count < NUMTAGS));
  411             tag++, count++) {
  412                 tlen = ntohs((*tag)->tag_len) + sizeof(**tag);
  413                 if ((length + tlen) > (ETHER_MAX_LEN - 4 - sizeof(*wh))) {
  414                         log(LOG_NOTICE, "ng_pppoe: tags too long\n");
  415                         sp->neg->numtags = count;
  416                         break;  /* XXX chop off what's too long */
  417                 }
  418                 bcopy(*tag, (char *)dp, tlen);
  419                 length += tlen;
  420                 dp += tlen;
  421         }
  422         wh->ph.length = htons(length);
  423         sp->neg->m->m_len = length + sizeof(*wh);
  424         sp->neg->m->m_pkthdr.len = length + sizeof(*wh);
  425 }
  426 
  427 /**************************************************************************
  428  * Routines to match a service.                                           *
  429  **************************************************************************/
  430 
  431 /*
  432  * Find a hook that has a service string that matches that
  433  * we are seeking. For now use a simple string.
  434  * In the future we may need something like regexp().
  435  *
  436  * Null string is a wildcard (ANY service), according to RFC2516.
  437  * And historical FreeBSD wildcard is also "*".
  438  */
  439 
  440 static hook_p
  441 pppoe_match_svc(node_p node, const struct pppoe_tag *tag)
  442 {
  443         const priv_p privp = NG_NODE_PRIVATE(node);
  444         sessp sp;
  445 
  446         LIST_FOREACH(sp, &privp->listeners, sessions) {
  447                 negp neg = sp->neg;
  448 
  449                 /* Empty Service-Name matches any service. */
  450                 if (neg->service_len == 0)
  451                         break;
  452 
  453                 /* Special case for a blank or "*" service name (wildcard). */
  454                 if (neg->service_len == 1 && neg->service.data[0] == '*')
  455                         break;
  456 
  457                 /* If the lengths don't match, that aint it. */
  458                 if (neg->service_len != ntohs(tag->tag_len))
  459                         continue;
  460 
  461                 if (strncmp((const char *)(tag + 1), neg->service.data,
  462                     ntohs(tag->tag_len)) == 0)
  463                         break;
  464         }
  465         CTR3(KTR_NET, "%20s: matched %p for %s", __func__,
  466             sp?sp->hook:NULL, (const char *)(tag + 1));
  467 
  468         return (sp?sp->hook:NULL);
  469 }
  470 
  471 /*
  472  * Broadcast the PADI packet in m0 to all listening hooks.
  473  * This routine is called when a PADI with empty Service-Name
  474  * tag is received. Client should receive PADOs with all
  475  * available services.
  476  */
  477 static int
  478 pppoe_broadcast_padi(node_p node, struct mbuf *m0)
  479 {
  480         const priv_p privp = NG_NODE_PRIVATE(node);
  481         sessp sp;
  482         int error = 0;
  483 
  484         LIST_FOREACH(sp, &privp->listeners, sessions) {
  485                 struct mbuf *m;
  486 
  487                 m = m_dup(m0, M_NOWAIT);
  488                 if (m == NULL)
  489                         return (ENOMEM);
  490                 NG_SEND_DATA_ONLY(error, sp->hook, m);
  491                 if (error)
  492                         return (error);
  493         }
  494 
  495         return (0);
  496 }
  497 
  498 /*
  499  * Find a hook, which name equals to given service.
  500  */
  501 static hook_p
  502 pppoe_find_svc(node_p node, const char *svc_name, int svc_len)
  503 {
  504         const priv_p privp = NG_NODE_PRIVATE(node);
  505         sessp sp;
  506 
  507         LIST_FOREACH(sp, &privp->listeners, sessions) {
  508                 negp neg = sp->neg;
  509 
  510                 if (neg->service_len == svc_len &&
  511                     strncmp(svc_name, neg->service.data, svc_len) == 0)
  512                         return (sp->hook);
  513         }
  514 
  515         return (NULL);
  516 }
  517 
  518 /**************************************************************************
  519  * Routines to find a particular session that matches an incoming packet. *
  520  **************************************************************************/
  521 /* Find free session and add to hash. */
  522 static uint16_t
  523 pppoe_getnewsession(sessp sp)
  524 {
  525         const priv_p privp = NG_NODE_PRIVATE(NG_HOOK_NODE(sp->hook));
  526         static uint16_t pppoe_sid = 1;
  527         sessp   tsp;
  528         uint16_t val, hash;
  529 
  530 restart:
  531         /* Atomicity is not needed here as value will be checked. */
  532         val = pppoe_sid++;
  533         /* Spec says 0xFFFF is reserved, also don't use 0x0000. */
  534         if (val == 0xffff || val == 0x0000)
  535                 val = pppoe_sid = 1;
  536 
  537         /* Check it isn't already in use. */
  538         hash = SESSHASH(val);
  539         mtx_lock(&privp->sesshash[hash].mtx);
  540         LIST_FOREACH(tsp, &privp->sesshash[hash].head, sessions) {
  541                 if (tsp->Session_ID == val)
  542                         break;
  543         }
  544         if (!tsp) {
  545                 sp->Session_ID = val;
  546                 LIST_INSERT_HEAD(&privp->sesshash[hash].head, sp, sessions);
  547         }
  548         mtx_unlock(&privp->sesshash[hash].mtx);
  549         if (tsp)
  550                 goto restart;
  551 
  552         CTR2(KTR_NET, "%20s: new sid %d", __func__, val);
  553 
  554         return (val);
  555 }
  556 
  557 /* Add specified session to hash. */
  558 static void
  559 pppoe_addsession(sessp sp)
  560 {
  561         const priv_p    privp = NG_NODE_PRIVATE(NG_HOOK_NODE(sp->hook));
  562         uint16_t        hash = SESSHASH(sp->Session_ID);
  563 
  564         mtx_lock(&privp->sesshash[hash].mtx);
  565         LIST_INSERT_HEAD(&privp->sesshash[hash].head, sp, sessions);
  566         mtx_unlock(&privp->sesshash[hash].mtx);
  567 }
  568 
  569 /* Delete specified session from hash. */
  570 static void
  571 pppoe_delsession(sessp sp)
  572 {
  573         const priv_p    privp = NG_NODE_PRIVATE(NG_HOOK_NODE(sp->hook));
  574         uint16_t        hash = SESSHASH(sp->Session_ID);
  575 
  576         mtx_lock(&privp->sesshash[hash].mtx);
  577         LIST_REMOVE(sp, sessions);
  578         mtx_unlock(&privp->sesshash[hash].mtx);
  579 }
  580 
  581 /* Find matching peer/session combination. */
  582 static sessp
  583 pppoe_findsession(priv_p privp, const struct pppoe_full_hdr *wh)
  584 {
  585         uint16_t        session = ntohs(wh->ph.sid);
  586         uint16_t        hash = SESSHASH(session);
  587         sessp           sp = NULL;
  588 
  589         mtx_lock(&privp->sesshash[hash].mtx);
  590         LIST_FOREACH(sp, &privp->sesshash[hash].head, sessions) {
  591                 if (sp->Session_ID == session &&
  592                     bcmp(sp->pkt_hdr.eh.ether_dhost,
  593                      wh->eh.ether_shost, ETHER_ADDR_LEN) == 0) {
  594                         break;
  595                 }
  596         }
  597         mtx_unlock(&privp->sesshash[hash].mtx);
  598         CTR3(KTR_NET, "%20s: matched %p for %d", __func__, sp?sp->hook:NULL,
  599             session);
  600 
  601         return (sp);
  602 }
  603 
  604 static hook_p
  605 pppoe_finduniq(node_p node, const struct pppoe_tag *tag)
  606 {
  607         hook_p  hook = NULL;
  608         sessp   sp;
  609 
  610         /* Cycle through all known hooks. */
  611         LIST_FOREACH(hook, &node->nd_hooks, hk_hooks) {
  612                 /* Skip any nonsession hook. */
  613                 if (NG_HOOK_PRIVATE(hook) == NULL)
  614                         continue;
  615                 sp = NG_HOOK_PRIVATE(hook);
  616                 /* Skip already connected sessions. */
  617                 if (sp->neg == NULL)
  618                         continue;
  619                 if (sp->neg->host_uniq_len == ntohs(tag->tag_len) &&
  620                     bcmp(sp->neg->host_uniq.data, (const char *)(tag + 1),
  621                      sp->neg->host_uniq_len) == 0)
  622                         break;
  623         }
  624         CTR3(KTR_NET, "%20s: matched %p for %p", __func__, hook, sp);
  625 
  626         return (hook);
  627 }
  628 
  629 static hook_p
  630 pppoe_findcookie(node_p node, const struct pppoe_tag *tag)
  631 {
  632         hook_p  hook = NULL;
  633         union uniq cookie;
  634 
  635         bcopy(tag + 1, cookie.bytes, sizeof(void *));
  636         /* Cycle through all known hooks. */
  637         LIST_FOREACH(hook, &node->nd_hooks, hk_hooks) {
  638                 /* Skip any nonsession hook. */
  639                 if (NG_HOOK_PRIVATE(hook) == NULL)
  640                         continue;
  641                 if (cookie.pointer == NG_HOOK_PRIVATE(hook))
  642                         break;
  643         }
  644         CTR3(KTR_NET, "%20s: matched %p for %p", __func__, hook, cookie.pointer);
  645 
  646         return (hook);
  647 }
  648 
  649 /**************************************************************************
  650  * Start of Netgraph entrypoints.                                         *
  651  **************************************************************************/
  652 
  653 /*
  654  * Allocate the private data structure and link it with node.
  655  */
  656 static int
  657 ng_pppoe_constructor(node_p node)
  658 {
  659         priv_p  privp;
  660         int     i;
  661 
  662         /* Initialize private descriptor. */
  663         privp = malloc(sizeof(*privp), M_NETGRAPH_PPPOE, M_WAITOK | M_ZERO);
  664 
  665         /* Link structs together; this counts as our one reference to *node. */
  666         NG_NODE_SET_PRIVATE(node, privp);
  667         privp->node = node;
  668 
  669         /* Initialize to standard mode. */
  670         memset(&privp->eh.ether_dhost, 0xff, ETHER_ADDR_LEN);
  671         privp->eh.ether_type = ETHERTYPE_PPPOE_DISC;
  672 
  673         LIST_INIT(&privp->listeners);
  674         for (i = 0; i < SESSHASHSIZE; i++) {
  675             mtx_init(&privp->sesshash[i].mtx, "PPPoE hash mutex", NULL, MTX_DEF);
  676             LIST_INIT(&privp->sesshash[i].head);
  677         }
  678 
  679         CTR3(KTR_NET, "%20s: created node [%x] (%p)",
  680             __func__, node->nd_ID, node);
  681 
  682         return (0);
  683 }
  684 
  685 /*
  686  * Give our ok for a hook to be added...
  687  * point the hook's private info to the hook structure.
  688  *
  689  * The following hook names are special:
  690  *  "ethernet":  the hook that should be connected to a NIC.
  691  *  "debug":    copies of data sent out here  (when I write the code).
  692  * All other hook names need only be unique. (the framework checks this).
  693  */
  694 static int
  695 ng_pppoe_newhook(node_p node, hook_p hook, const char *name)
  696 {
  697         const priv_p privp = NG_NODE_PRIVATE(node);
  698         sessp sp;
  699 
  700         if (strcmp(name, NG_PPPOE_HOOK_ETHERNET) == 0) {
  701                 privp->ethernet_hook = hook;
  702                 NG_HOOK_SET_RCVDATA(hook, ng_pppoe_rcvdata_ether);
  703         } else if (strcmp(name, NG_PPPOE_HOOK_DEBUG) == 0) {
  704                 privp->debug_hook = hook;
  705                 NG_HOOK_SET_RCVDATA(hook, ng_pppoe_rcvdata_debug);
  706         } else {
  707                 /*
  708                  * Any other unique name is OK.
  709                  * The infrastructure has already checked that it's unique,
  710                  * so just allocate it and hook it in.
  711                  */
  712                 sp = malloc(sizeof(*sp), M_NETGRAPH_PPPOE, M_NOWAIT | M_ZERO);
  713                 if (sp == NULL)
  714                         return (ENOMEM);
  715 
  716                 NG_HOOK_SET_PRIVATE(hook, sp);
  717                 sp->hook = hook;
  718         }
  719         CTR5(KTR_NET, "%20s: node [%x] (%p) connected hook %s (%p)",
  720             __func__, node->nd_ID, node, name, hook);
  721 
  722         return(0);
  723 }
  724 
  725 /*
  726  * Hook has been added successfully. Request the MAC address of
  727  * the underlying Ethernet node.
  728  */
  729 static int
  730 ng_pppoe_connect(hook_p hook)
  731 {
  732         const priv_p privp = NG_NODE_PRIVATE(NG_HOOK_NODE(hook));
  733         struct ng_mesg *msg;
  734         int error;
  735 
  736         if (hook != privp->ethernet_hook)
  737                 return (0);
  738 
  739         /*
  740          * If this is Ethernet hook, then request MAC address
  741          * from our downstream.
  742          */
  743         NG_MKMESSAGE(msg, NGM_ETHER_COOKIE, NGM_ETHER_GET_ENADDR, 0, M_NOWAIT);
  744         if (msg == NULL)
  745                 return (ENOBUFS);
  746 
  747         /*
  748          * Our hook and peer hook have HK_INVALID flag set,
  749          * so we can't use NG_SEND_MSG_HOOK() macro here.
  750          */
  751         NG_SEND_MSG_ID(error, privp->node, msg,
  752             NG_NODE_ID(NG_PEER_NODE(privp->ethernet_hook)),
  753             NG_NODE_ID(privp->node));
  754 
  755         return (error);
  756 }
  757 /*
  758  * Get a netgraph control message.
  759  * Check it is one we understand. If needed, send a response.
  760  * We sometimes save the address for an async action later.
  761  * Always free the message.
  762  */
  763 static int
  764 ng_pppoe_rcvmsg(node_p node, item_p item, hook_p lasthook)
  765 {
  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] == '' &&
  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                         pppoe_start(sp);
  986                         break;
  987                     }
  988                 case NGM_PPPOE_LISTEN:
  989                         /*
  990                          * Check the hook exists and is Uninitialised.
  991                          * Install the service matching string.
  992                          * Store the originator of this message so we can send
  993                          * a success or fail message to them later.
  994                          * Move the hook to 'LISTENING'
  995                          */
  996                         neg->service.hdr.tag_type = PTT_SRV_NAME;
  997                         neg->service.hdr.tag_len =
  998                             htons((uint16_t)ourmsg->data_len);
  999 
 1000                         if (ourmsg->data_len)
 1001                                 bcopy(ourmsg->data, neg->service.data,
 1002                                     ourmsg->data_len);
 1003                         neg->service_len = ourmsg->data_len;
 1004                         neg->pkt->pkt_header.ph.code = PADT_CODE;
 1005                         /*
 1006                          * Wait for PADI packet coming from Ethernet.
 1007                          */
 1008                         sp->state = PPPOE_LISTENING;
 1009                         LIST_INSERT_HEAD(&privp->listeners, sp, sessions);
 1010                         break;
 1011                 case NGM_PPPOE_OFFER:
 1012                         /*
 1013                          * Check the hook exists and is Uninitialised.
 1014                          * Store the originator of this message so we can send
 1015                          * a success of fail message to them later.
 1016                          * Store the AC-Name given and go to PRIMED.
 1017                          */
 1018                         neg->ac_name.hdr.tag_type = PTT_AC_NAME;
 1019                         neg->ac_name.hdr.tag_len =
 1020                             htons((uint16_t)ourmsg->data_len);
 1021                         if (ourmsg->data_len)
 1022                                 bcopy(ourmsg->data, neg->ac_name.data,
 1023                                     ourmsg->data_len);
 1024                         neg->ac_name_len = ourmsg->data_len;
 1025                         neg->pkt->pkt_header.ph.code = PADO_CODE;
 1026                         /*
 1027                          * Wait for PADI packet coming from hook.
 1028                          */
 1029                         sp->state = PPPOE_PRIMED;
 1030                         break;
 1031                 case NGM_PPPOE_SERVICE:
 1032                         /*
 1033                          * Check the session is primed.
 1034                          * for now just allow ONE service to be advertised.
 1035                          * If you do it twice you just overwrite.
 1036                          */
 1037                         if (sp->state != PPPOE_PRIMED) {
 1038                                 log(LOG_NOTICE, "ng_pppoe[%x]: session not "
 1039                                     "primed\n", node->nd_ID);
 1040                                 LEAVE(EISCONN);
 1041                         }
 1042                         neg = sp->neg;
 1043                         neg->service.hdr.tag_type = PTT_SRV_NAME;
 1044                         neg->service.hdr.tag_len =
 1045                             htons((uint16_t)ourmsg->data_len);
 1046 
 1047                         if (ourmsg->data_len)
 1048                                 bcopy(ourmsg->data, neg->service.data,
 1049                                     ourmsg->data_len);
 1050                         neg->service_len = ourmsg->data_len;
 1051                         break;
 1052                 case NGM_PPPOE_SETMODE:
 1053                     {
 1054                         char *s;
 1055                         size_t len;
 1056 
 1057                         if (msg->header.arglen == 0)
 1058                                 LEAVE(EINVAL);
 1059 
 1060                         s = (char *)msg->data;
 1061                         len = msg->header.arglen - 1;
 1062 
 1063                         /* Search for matching mode string. */
 1064                         if (len == strlen(NG_PPPOE_STANDARD) &&
 1065                             (strncmp(NG_PPPOE_STANDARD, s, len) == 0)) {
 1066                                 privp->flags = 0;
 1067                                 privp->eh.ether_type = ETHERTYPE_PPPOE_DISC;
 1068                                 break;
 1069                         }
 1070                         if (len == strlen(NG_PPPOE_3COM) &&
 1071                             (strncmp(NG_PPPOE_3COM, s, len) == 0)) {
 1072                                 privp->flags |= COMPAT_3COM;
 1073                                 privp->eh.ether_type =
 1074                                     ETHERTYPE_PPPOE_3COM_DISC;
 1075                                 break;
 1076                         }
 1077                         if (len == strlen(NG_PPPOE_DLINK) &&
 1078                             (strncmp(NG_PPPOE_DLINK, s, len) == 0)) {
 1079                                 privp->flags |= COMPAT_DLINK;
 1080                                 break;
 1081                         }
 1082                         error = EINVAL;
 1083                         break;
 1084                     }
 1085                 case NGM_PPPOE_GETMODE:
 1086                     {
 1087                         char *s;
 1088                         size_t len = 0;
 1089 
 1090                         if (privp->flags == 0)
 1091                                 len += strlen(NG_PPPOE_STANDARD) + 1;
 1092                         if (privp->flags & COMPAT_3COM)
 1093                                 len += strlen(NG_PPPOE_3COM) + 1;
 1094                         if (privp->flags & COMPAT_DLINK)
 1095                                 len += strlen(NG_PPPOE_DLINK) + 1;
 1096 
 1097                         NG_MKRESPONSE(resp, msg, len, M_NOWAIT);
 1098                         if (resp == NULL)
 1099                                 LEAVE(ENOMEM);
 1100 
 1101                         s = (char *)resp->data;
 1102                         if (privp->flags == 0) {
 1103                                 len = strlen(NG_PPPOE_STANDARD);
 1104                                 strlcpy(s, NG_PPPOE_STANDARD, len + 1);
 1105                                 break;
 1106                         }
 1107                         if (privp->flags & COMPAT_3COM) {
 1108                                 len = strlen(NG_PPPOE_3COM);
 1109                                 strlcpy(s, NG_PPPOE_3COM, len + 1);
 1110                                 s += len;
 1111                         }
 1112                         if (privp->flags & COMPAT_DLINK) {
 1113                                 if (s != resp->data)
 1114                                         *s++ = '|';
 1115                                 len = strlen(NG_PPPOE_DLINK);
 1116                                 strlcpy(s, NG_PPPOE_DLINK, len + 1);
 1117                         }
 1118                         break;
 1119                     }
 1120                 case NGM_PPPOE_SETENADDR:
 1121                         if (msg->header.arglen != ETHER_ADDR_LEN)
 1122                                 LEAVE(EINVAL);
 1123                         bcopy(msg->data, &privp->eh.ether_shost,
 1124                             ETHER_ADDR_LEN);
 1125                         break;
 1126                 case NGM_PPPOE_SETMAXP:
 1127                         if (msg->header.arglen != sizeof(uint16_t))
 1128                                 LEAVE(EINVAL);
 1129                         privp->max_payload.hdr.tag_type = PTT_MAX_PAYL;
 1130                         privp->max_payload.hdr.tag_len = htons(sizeof(uint16_t));
 1131                         privp->max_payload.data = htons(*((uint16_t *)msg->data));
 1132                         break;
 1133                 case NGM_PPPOE_SEND_HURL:
 1134                     {
 1135                         struct mbuf *m;
 1136 
 1137                         /* Generate a packet of that type. */
 1138                         m = m_gethdr(M_NOWAIT, MT_DATA);
 1139                         if (m == NULL)
 1140                                 log(LOG_NOTICE, "ng_pppoe[%x]: session out of "
 1141                                     "mbufs\n", node->nd_ID);
 1142                         else {
 1143                                 struct pppoe_full_hdr *wh;
 1144                                 struct pppoe_tag *tag;
 1145                                 int     error = 0;
 1146 
 1147                                 wh = mtod(m, struct pppoe_full_hdr *);
 1148                                 bcopy(&sp->pkt_hdr, wh, sizeof(*wh));
 1149 
 1150                                 /* Revert the stored header to DISC/PADM mode. */
 1151                                 wh->ph.code = PADM_CODE;
 1152                                 /*
 1153                                  * Configure ethertype depending on what
 1154                                  * was used during sessions stage.
 1155                                  */
 1156                                 if (wh->eh.ether_type ==
 1157                                     ETHERTYPE_PPPOE_3COM_SESS)
 1158                                         wh->eh.ether_type = ETHERTYPE_PPPOE_3COM_DISC;
 1159                                 else
 1160                                         wh->eh.ether_type = ETHERTYPE_PPPOE_DISC;
 1161                                 /*
 1162                                  * Add PADM message and adjust sizes.
 1163                                  */
 1164                                 tag = (void *)(&wh->ph + 1);
 1165                                 tag->tag_type = PTT_HURL;
 1166                                 tag->tag_len = htons(ourmsg->data_len);
 1167                                 strncpy((char *)(tag + 1), ourmsg->data, ourmsg->data_len);
 1168                                 m->m_pkthdr.len = m->m_len = sizeof(*wh) + sizeof(*tag) +
 1169                                     ourmsg->data_len;
 1170                                 wh->ph.length = htons(sizeof(*tag) + ourmsg->data_len);
 1171                                 NG_SEND_DATA_ONLY(error,
 1172                                     privp->ethernet_hook, m);
 1173                         }
 1174                         break;
 1175                     }
 1176                 case NGM_PPPOE_SEND_MOTM:
 1177                     {
 1178                         struct mbuf *m;
 1179 
 1180                         /* Generate a packet of that type. */
 1181                         m = m_gethdr(M_NOWAIT, MT_DATA);
 1182                         if (m == NULL)
 1183                                 log(LOG_NOTICE, "ng_pppoe[%x]: session out of "
 1184                                     "mbufs\n", node->nd_ID);
 1185                         else {
 1186                                 struct pppoe_full_hdr *wh;
 1187                                 struct pppoe_tag *tag;
 1188                                 int     error = 0;
 1189 
 1190                                 wh = mtod(m, struct pppoe_full_hdr *);
 1191                                 bcopy(&sp->pkt_hdr, wh, sizeof(*wh));
 1192 
 1193                                 /* Revert the stored header to DISC/PADM mode. */
 1194                                 wh->ph.code = PADM_CODE;
 1195                                 /*
 1196                                  * Configure ethertype depending on what
 1197                                  * was used during sessions stage.
 1198                                  */
 1199                                 if (wh->eh.ether_type ==
 1200                                     ETHERTYPE_PPPOE_3COM_SESS)
 1201                                         wh->eh.ether_type = ETHERTYPE_PPPOE_3COM_DISC;
 1202                                 else
 1203                                         wh->eh.ether_type = ETHERTYPE_PPPOE_DISC;
 1204                                 /*
 1205                                  * Add PADM message and adjust sizes.
 1206                                  */
 1207                                 tag = (void *)(&wh->ph + 1);
 1208                                 tag->tag_type = PTT_MOTM;
 1209                                 tag->tag_len = htons(ourmsg->data_len);
 1210                                 strncpy((char *)(tag + 1), ourmsg->data, ourmsg->data_len);
 1211                                 m->m_pkthdr.len = m->m_len = sizeof(*wh) + sizeof(*tag) +
 1212                                     ourmsg->data_len;
 1213                                 wh->ph.length = htons(sizeof(*tag) + ourmsg->data_len);
 1214                                 NG_SEND_DATA_ONLY(error,
 1215                                     privp->ethernet_hook, m);
 1216                         }
 1217                         break;
 1218                     }
 1219                 default:
 1220                         LEAVE(EINVAL);
 1221                 }
 1222                 break;
 1223         case NGM_ETHER_COOKIE:
 1224                 if (!(msg->header.flags & NGF_RESP))
 1225                         LEAVE(EINVAL);
 1226                 switch (msg->header.cmd) {
 1227                 case NGM_ETHER_GET_ENADDR:
 1228                         if (msg->header.arglen != ETHER_ADDR_LEN)
 1229                                 LEAVE(EINVAL);
 1230                         bcopy(msg->data, &privp->eh.ether_shost,
 1231                             ETHER_ADDR_LEN);
 1232                         break;
 1233                 default:
 1234                         LEAVE(EINVAL);
 1235                 }
 1236                 break;
 1237         default:
 1238                 LEAVE(EINVAL);
 1239         }
 1240 
 1241         /* Take care of synchronous response, if any. */
 1242 quit:
 1243         CTR2(KTR_NET, "%20s: returning %d", __func__, error);
 1244         NG_RESPOND_MSG(error, node, item, resp);
 1245         /* Free the message and return. */
 1246         NG_FREE_MSG(msg);
 1247         return(error);
 1248 }
 1249 
 1250 /*
 1251  * Start a client into the first state. A separate function because
 1252  * it can be needed if the negotiation times out.
 1253  */
 1254 static void
 1255 pppoe_start(sessp sp)
 1256 {
 1257         hook_p  hook = sp->hook;
 1258         node_p  node = NG_HOOK_NODE(hook);
 1259         priv_p  privp = NG_NODE_PRIVATE(node);
 1260         negp    neg = sp->neg;
 1261         struct  mbuf *m0;
 1262         int     error;
 1263 
 1264         /*
 1265          * Kick the state machine into starting up.
 1266          */
 1267         CTR2(KTR_NET, "%20s: called %d", __func__, sp->Session_ID);
 1268         sp->state = PPPOE_SINIT;
 1269         /*
 1270          * Reset the packet header to broadcast. Since we are
 1271          * in a client mode use configured ethertype.
 1272          */
 1273         memcpy((void *)&neg->pkt->pkt_header.eh, &privp->eh,
 1274             sizeof(struct ether_header));
 1275         neg->pkt->pkt_header.ph.code = PADI_CODE;
 1276         init_tags(sp);
 1277         insert_tag(sp, &neg->host_uniq.hdr);
 1278         insert_tag(sp, &neg->service.hdr);
 1279         if (privp->max_payload.data != 0)
 1280                 insert_tag(sp, &privp->max_payload.hdr);
 1281         make_packet(sp);
 1282         /*
 1283          * Send packet and prepare to retransmit it after timeout.
 1284          */
 1285         ng_callout(&neg->handle, node, hook, PPPOE_INITIAL_TIMEOUT * hz,
 1286             pppoe_ticker, NULL, 0);
 1287         neg->timeout = PPPOE_INITIAL_TIMEOUT * 2;
 1288         m0 = m_copypacket(neg->m, M_NOWAIT);
 1289         NG_SEND_DATA_ONLY(error, privp->ethernet_hook, m0);
 1290 }
 1291 
 1292 static int
 1293 send_acname(sessp sp, const struct pppoe_tag *tag)
 1294 {
 1295         int error, tlen;
 1296         struct ng_mesg *msg;
 1297         struct ngpppoe_sts *sts;
 1298 
 1299         CTR2(KTR_NET, "%20s: called %d", __func__, sp->Session_ID);
 1300 
 1301         NG_MKMESSAGE(msg, NGM_PPPOE_COOKIE, NGM_PPPOE_ACNAME,
 1302             sizeof(struct ngpppoe_sts), M_NOWAIT);
 1303         if (msg == NULL)
 1304                 return (ENOMEM);
 1305 
 1306         sts = (struct ngpppoe_sts *)msg->data;
 1307         tlen = min(NG_HOOKSIZ - 1, ntohs(tag->tag_len));
 1308         strncpy(sts->hook, (const char *)(tag + 1), tlen);
 1309         sts->hook[tlen] = '\0';
 1310         NG_SEND_MSG_ID(error, NG_HOOK_NODE(sp->hook), msg, sp->creator, 0);
 1311 
 1312         return (error);
 1313 }
 1314 
 1315 static int
 1316 send_sessionid(sessp sp)
 1317 {
 1318         int error;
 1319         struct ng_mesg *msg;
 1320 
 1321         CTR2(KTR_NET, "%20s: called %d", __func__, sp->Session_ID);
 1322 
 1323         NG_MKMESSAGE(msg, NGM_PPPOE_COOKIE, NGM_PPPOE_SESSIONID,
 1324             sizeof(uint16_t), M_NOWAIT);
 1325         if (msg == NULL)
 1326                 return (ENOMEM);
 1327 
 1328         *(uint16_t *)msg->data = sp->Session_ID;
 1329         NG_SEND_MSG_ID(error, NG_HOOK_NODE(sp->hook), msg, sp->creator, 0);
 1330 
 1331         return (error);
 1332 }
 1333 
 1334 static int
 1335 send_maxp(sessp sp, const struct pppoe_tag *tag)
 1336 {
 1337         int error;
 1338         struct ng_mesg *msg;
 1339         struct ngpppoe_maxp *maxp;
 1340 
 1341         CTR2(KTR_NET, "%20s: called %d", __func__, sp->Session_ID);
 1342 
 1343         NG_MKMESSAGE(msg, NGM_PPPOE_COOKIE, NGM_PPPOE_SETMAXP,
 1344             sizeof(struct ngpppoe_maxp), M_NOWAIT);
 1345         if (msg == NULL)
 1346                 return (ENOMEM);
 1347 
 1348         maxp = (struct ngpppoe_maxp *)msg->data;
 1349         strncpy(maxp->hook, NG_HOOK_NAME(sp->hook), NG_HOOKSIZ);
 1350         maxp->data = ntohs(((const struct maxptag *)tag)->data);
 1351         NG_SEND_MSG_ID(error, NG_HOOK_NODE(sp->hook), msg, sp->creator, 0);
 1352 
 1353         return (error);
 1354 }
 1355 
 1356 static int
 1357 send_hurl(sessp sp, const struct pppoe_tag *tag)
 1358 {
 1359         int error, tlen;
 1360         struct ng_mesg *msg;
 1361         struct ngpppoe_padm *padm;
 1362 
 1363         CTR2(KTR_NET, "%20s: called %d", __func__, sp->Session_ID);
 1364 
 1365         NG_MKMESSAGE(msg, NGM_PPPOE_COOKIE, NGM_PPPOE_HURL,
 1366             sizeof(struct ngpppoe_padm), M_NOWAIT);
 1367         if (msg == NULL)
 1368                 return (ENOMEM);
 1369 
 1370         padm = (struct ngpppoe_padm *)msg->data;
 1371         tlen = min(PPPOE_PADM_VALUE_SIZE - 1, ntohs(tag->tag_len));
 1372         strncpy(padm->msg, (const char *)(tag + 1), tlen);
 1373         padm->msg[tlen] = '\0';
 1374         NG_SEND_MSG_ID(error, NG_HOOK_NODE(sp->hook), msg, sp->creator, 0);
 1375 
 1376         return (error);
 1377 }
 1378 
 1379 static int
 1380 send_motm(sessp sp, const struct pppoe_tag *tag)
 1381 {
 1382         int error, tlen;
 1383         struct ng_mesg *msg;
 1384         struct ngpppoe_padm *padm;
 1385 
 1386         CTR2(KTR_NET, "%20s: called %d", __func__, sp->Session_ID);
 1387 
 1388         NG_MKMESSAGE(msg, NGM_PPPOE_COOKIE, NGM_PPPOE_MOTM,
 1389             sizeof(struct ngpppoe_padm), M_NOWAIT);
 1390         if (msg == NULL)
 1391                 return (ENOMEM);
 1392 
 1393         padm = (struct ngpppoe_padm *)msg->data;
 1394         tlen = min(PPPOE_PADM_VALUE_SIZE - 1, ntohs(tag->tag_len));
 1395         strncpy(padm->msg, (const char *)(tag + 1), tlen);
 1396         padm->msg[tlen] = '\0';
 1397         NG_SEND_MSG_ID(error, NG_HOOK_NODE(sp->hook), msg, sp->creator, 0);
 1398 
 1399         return (error);
 1400 }
 1401 
 1402 /*
 1403  * Receive data from session hook and do something with it.
 1404  */
 1405 static int
 1406 ng_pppoe_rcvdata(hook_p hook, item_p item)
 1407 {
 1408         node_p                  node = NG_HOOK_NODE(hook);
 1409         const priv_p            privp = NG_NODE_PRIVATE(node);
 1410         sessp                   sp = NG_HOOK_PRIVATE(hook);
 1411         struct pppoe_full_hdr   *wh;
 1412         struct mbuf             *m;
 1413         int                     error;
 1414 
 1415         CTR6(KTR_NET, "%20s: node [%x] (%p) received %p on \"%s\" (%p)",
 1416             __func__, node->nd_ID, node, item, hook->hk_name, hook);
 1417 
 1418         NGI_GET_M(item, m);
 1419         switch (sp->state) {
 1420         case    PPPOE_NEWCONNECTED:
 1421         case    PPPOE_CONNECTED: {
 1422                 /*
 1423                  * Remove PPP address and control fields, if any.
 1424                  * For example, ng_ppp(4) always sends LCP packets
 1425                  * with address and control fields as required by
 1426                  * generic PPP. PPPoE is an exception to the rule.
 1427                  */
 1428                 if (m->m_pkthdr.len >= 2) {
 1429                         if (m->m_len < 2 && !(m = m_pullup(m, 2)))
 1430                                 LEAVE(ENOBUFS);
 1431                         if (mtod(m, u_char *)[0] == 0xff &&
 1432                             mtod(m, u_char *)[1] == 0x03)
 1433                                 m_adj(m, 2);
 1434                 }
 1435                 /*
 1436                  * Bang in a pre-made header, and set the length up
 1437                  * to be correct. Then send it to the ethernet driver.
 1438                  */
 1439                 M_PREPEND(m, sizeof(*wh), M_NOWAIT);
 1440                 if (m == NULL)
 1441                         LEAVE(ENOBUFS);
 1442 
 1443                 wh = mtod(m, struct pppoe_full_hdr *);
 1444                 bcopy(&sp->pkt_hdr, wh, sizeof(*wh));
 1445                 wh->ph.length = htons(m->m_pkthdr.len - sizeof(*wh));
 1446                 NG_FWD_NEW_DATA(error, item, privp->ethernet_hook, m);
 1447                 privp->packets_out++;
 1448                 break;
 1449                 }
 1450         case    PPPOE_PRIMED: {
 1451                 struct {
 1452                         struct pppoe_tag hdr;
 1453                         union   uniq    data;
 1454                 } __packed      uniqtag;
 1455                 const struct pppoe_tag  *tag;
 1456                 struct mbuf     *m0;
 1457                 const struct pppoe_hdr  *ph;
 1458                 negp            neg = sp->neg;
 1459                 uint16_t        session;
 1460                 uint16_t        length;
 1461                 uint8_t         code;
 1462 
 1463                 /*
 1464                  * A PADI packet is being returned by the application
 1465                  * that has set up this hook. This indicates that it
 1466                  * wants us to offer service.
 1467                  */
 1468                 if (m->m_len < sizeof(*wh)) {
 1469                         m = m_pullup(m, sizeof(*wh));
 1470                         if (m == NULL)
 1471                                 LEAVE(ENOBUFS);
 1472                 }
 1473                 wh = mtod(m, struct pppoe_full_hdr *);
 1474                 ph = &wh->ph;
 1475                 session = ntohs(wh->ph.sid);
 1476                 length = ntohs(wh->ph.length);
 1477                 code = wh->ph.code;
 1478                 /* Use peers mode in session. */
 1479                 neg->pkt->pkt_header.eh.ether_type = wh->eh.ether_type;
 1480                 if (code != PADI_CODE)
 1481                         LEAVE(EINVAL);
 1482                 ng_uncallout(&neg->handle, node);
 1483 
 1484                 /*
 1485                  * This is the first time we hear
 1486                  * from the client, so note it's
 1487                  * unicast address, replacing the
 1488                  * broadcast address.
 1489                  */
 1490                 bcopy(wh->eh.ether_shost,
 1491                         neg->pkt->pkt_header.eh.ether_dhost,
 1492                         ETHER_ADDR_LEN);
 1493                 sp->state = PPPOE_SOFFER;
 1494                 neg->timeout = 0;
 1495                 neg->pkt->pkt_header.ph.code = PADO_CODE;
 1496 
 1497                 /*
 1498                  * Start working out the tags to respond with.
 1499                  */
 1500                 uniqtag.hdr.tag_type = PTT_AC_COOKIE;
 1501                 uniqtag.hdr.tag_len = htons((u_int16_t)sizeof(sp));
 1502                 uniqtag.data.pointer = sp;
 1503                 init_tags(sp);
 1504                 insert_tag(sp, &neg->ac_name.hdr); /* AC_NAME */
 1505                 if ((tag = get_tag(ph, PTT_SRV_NAME)))
 1506                         insert_tag(sp, tag);      /* return service */
 1507                 /*
 1508                  * If we have a NULL service request
 1509                  * and have an extra service defined in this hook,
 1510                  * then also add a tag for the extra service.
 1511                  * XXX this is a hack. eventually we should be able
 1512                  * to support advertising many services, not just one
 1513                  */
 1514                 if (((tag == NULL) || (tag->tag_len == 0)) &&
 1515                     (neg->service.hdr.tag_len != 0)) {
 1516                         insert_tag(sp, &neg->service.hdr); /* SERVICE */
 1517                 }
 1518                 if ((tag = get_tag(ph, PTT_HOST_UNIQ)))
 1519                         insert_tag(sp, tag); /* returned hostunique */
 1520                 insert_tag(sp, &uniqtag.hdr);
 1521                 scan_tags(sp, ph);
 1522                 make_packet(sp);
 1523                 /*
 1524                  * Send the offer but if they don't respond
 1525                  * in PPPOE_OFFER_TIMEOUT seconds, forget about it.
 1526                  */
 1527                 ng_callout(&neg->handle, node, hook, PPPOE_OFFER_TIMEOUT * hz,
 1528                     pppoe_ticker, NULL, 0);
 1529                 m0 = m_copypacket(sp->neg->m, M_NOWAIT);
 1530                 NG_FWD_NEW_DATA(error, item, privp->ethernet_hook, m0);
 1531                 privp->packets_out++;
 1532                 break;
 1533                 }
 1534 
 1535         /*
 1536          * Packets coming from the hook make no sense
 1537          * to sessions in the rest of states. Throw them away.
 1538          */
 1539         default:
 1540                 LEAVE(ENETUNREACH);
 1541         }
 1542 quit:
 1543         if (item)
 1544                 NG_FREE_ITEM(item);
 1545         NG_FREE_M(m);
 1546         return (error);
 1547 }
 1548 
 1549 /*
 1550  * Receive data from ether and do something with it.
 1551  */
 1552 static int
 1553 ng_pppoe_rcvdata_ether(hook_p hook, item_p item)
 1554 {
 1555         node_p                  node = NG_HOOK_NODE(hook);
 1556         const priv_p            privp = NG_NODE_PRIVATE(node);
 1557         sessp                   sp;
 1558         const struct pppoe_tag  *utag = NULL, *tag = NULL;
 1559         const struct pppoe_tag  sntag = { PTT_SRV_NAME, 0 };
 1560         const struct pppoe_full_hdr *wh;
 1561         const struct pppoe_hdr  *ph;
 1562         negp                    neg = NULL;
 1563         struct mbuf             *m;
 1564         hook_p                  sendhook;
 1565         int                     error = 0;
 1566         uint16_t                session;
 1567         uint16_t                length;
 1568         uint8_t                 code;
 1569         struct  mbuf            *m0;
 1570 
 1571         CTR6(KTR_NET, "%20s: node [%x] (%p) received %p on \"%s\" (%p)",
 1572             __func__, node->nd_ID, node, item, hook->hk_name, hook);
 1573 
 1574         NGI_GET_M(item, m);
 1575         /*
 1576          * Dig out various fields from the packet.
 1577          * Use them to decide where to send it.
 1578          */
 1579         privp->packets_in++;
 1580         if( m->m_len < sizeof(*wh)) {
 1581                 m = m_pullup(m, sizeof(*wh)); /* Checks length */
 1582                 if (m == NULL) {
 1583                         log(LOG_NOTICE, "ng_pppoe[%x]: couldn't "
 1584                             "m_pullup(wh)\n", node->nd_ID);
 1585                         LEAVE(ENOBUFS);
 1586                 }
 1587         }
 1588         wh = mtod(m, struct pppoe_full_hdr *);
 1589         length = ntohs(wh->ph.length);
 1590         switch(wh->eh.ether_type) {
 1591         case    ETHERTYPE_PPPOE_3COM_DISC: /* fall through */
 1592         case    ETHERTYPE_PPPOE_DISC:
 1593                 /*
 1594                  * We need to try to make sure that the tag area
 1595                  * is contiguous, or we could wander off the end
 1596                  * of a buffer and make a mess.
 1597                  * (Linux wouldn't have this problem).
 1598                  */
 1599                 if (m->m_pkthdr.len <= MHLEN) {
 1600                         if( m->m_len < m->m_pkthdr.len) {
 1601                                 m = m_pullup(m, m->m_pkthdr.len);
 1602                                 if (m == NULL) {
 1603                                         log(LOG_NOTICE, "ng_pppoe[%x]: "
 1604                                             "couldn't m_pullup(pkthdr)\n",
 1605                                             node->nd_ID);
 1606                                         LEAVE(ENOBUFS);
 1607                                 }
 1608                         }
 1609                 }
 1610                 if (m->m_len != m->m_pkthdr.len) {
 1611                         /*
 1612                          * It's not all in one piece.
 1613                          * We need to do extra work.
 1614                          * Put it into a cluster.
 1615                          */
 1616                         struct mbuf *n;
 1617                         n = m_dup(m, M_NOWAIT);
 1618                         m_freem(m);
 1619                         m = n;
 1620                         if (m) {
 1621                                 /* just check we got a cluster */
 1622                                 if (m->m_len != m->m_pkthdr.len) {
 1623                                         m_freem(m);
 1624                                         m = NULL;
 1625                                 }
 1626                         }
 1627                         if (m == NULL) {
 1628                                 log(LOG_NOTICE, "ng_pppoe[%x]: packet "
 1629                                     "fragmented\n", node->nd_ID);
 1630                                 LEAVE(EMSGSIZE);
 1631                         }
 1632                 }
 1633                 wh = mtod(m, struct pppoe_full_hdr *);
 1634                 length = ntohs(wh->ph.length);
 1635                 ph = &wh->ph;
 1636                 session = ntohs(wh->ph.sid);
 1637                 code = wh->ph.code;
 1638 
 1639                 switch(code) {
 1640                 case    PADI_CODE:
 1641                         /*
 1642                          * We are a server:
 1643                          * Look for a hook with the required service and send
 1644                          * the ENTIRE packet up there. It should come back to
 1645                          * a new hook in PRIMED state. Look there for further
 1646                          * processing.
 1647                          */
 1648                         tag = get_tag(ph, PTT_SRV_NAME);
 1649                         if (tag == NULL)
 1650                                 tag = &sntag;
 1651 
 1652                         /*
 1653                          * First, try to match Service-Name against our 
 1654                          * listening hooks. If no success and we are in D-Link
 1655                          * compat mode and Service-Name is empty, then we 
 1656                          * broadcast the PADI to all listening hooks.
 1657                          */
 1658                         sendhook = pppoe_match_svc(node, tag);
 1659                         if (sendhook != NULL)
 1660                                 NG_FWD_NEW_DATA(error, item, sendhook, m);
 1661                         else if (privp->flags & COMPAT_DLINK &&
 1662                                  ntohs(tag->tag_len) == 0)
 1663                                 error = pppoe_broadcast_padi(node, m);
 1664                         else
 1665                                 error = ENETUNREACH;
 1666                         break;
 1667                 case    PADO_CODE:
 1668                         /*
 1669                          * We are a client:
 1670                          * Use the host_uniq tag to find the hook this is in
 1671                          * response to. Received #2, now send #3
 1672                          * For now simply accept the first we receive.
 1673                          */
 1674                         utag = get_tag(ph, PTT_HOST_UNIQ);
 1675                         if (utag == NULL) {
 1676                                 log(LOG_NOTICE, "ng_pppoe[%x]: no host "
 1677                                     "unique field\n", node->nd_ID);
 1678                                 LEAVE(ENETUNREACH);
 1679                         }
 1680 
 1681                         sendhook = pppoe_finduniq(node, utag);
 1682                         if (sendhook == NULL) {
 1683                                 log(LOG_NOTICE, "ng_pppoe[%x]: no "
 1684                                     "matching session\n", node->nd_ID);
 1685                                 LEAVE(ENETUNREACH);
 1686                         }
 1687 
 1688                         /*
 1689                          * Check the session is in the right state.
 1690                          * It needs to be in PPPOE_SINIT.
 1691                          */
 1692                         sp = NG_HOOK_PRIVATE(sendhook);
 1693                         if (sp->state == PPPOE_SREQ ||
 1694                             sp->state == PPPOE_CONNECTED) {
 1695                                 break;  /* Multiple PADO is OK. */
 1696                         }
 1697                         if (sp->state != PPPOE_SINIT) {
 1698                                 log(LOG_NOTICE, "ng_pppoe[%x]: session "
 1699                                     "in wrong state\n", node->nd_ID);
 1700                                 LEAVE(ENETUNREACH);
 1701                         }
 1702                         neg = sp->neg;
 1703                         /* If requested specific AC-name, check it. */
 1704                         if (neg->ac_name_len) {
 1705                                 tag = get_tag(ph, PTT_AC_NAME);
 1706                                 if (!tag) {
 1707                                         /* No PTT_AC_NAME in PADO */
 1708                                         break;
 1709                                 }
 1710                                 if (neg->ac_name_len != htons(tag->tag_len) ||
 1711                                     strncmp(neg->ac_name.data,
 1712                                     (const char *)(tag + 1),
 1713                                     neg->ac_name_len) != 0) {
 1714                                         break;
 1715                                 }
 1716                         }
 1717                         sp->state = PPPOE_SREQ;
 1718                         ng_uncallout(&neg->handle, node);
 1719 
 1720                         /*
 1721                          * This is the first time we hear
 1722                          * from the server, so note it's
 1723                          * unicast address, replacing the
 1724                          * broadcast address .
 1725                          */
 1726                         bcopy(wh->eh.ether_shost,
 1727                                 neg->pkt->pkt_header.eh.ether_dhost,
 1728                                 ETHER_ADDR_LEN);
 1729                         neg->timeout = 0;
 1730                         neg->pkt->pkt_header.ph.code = PADR_CODE;
 1731                         init_tags(sp);
 1732                         insert_tag(sp, utag);           /* Host Unique */
 1733                         if ((tag = get_tag(ph, PTT_AC_COOKIE)))
 1734                                 insert_tag(sp, tag);    /* return cookie */
 1735                         if ((tag = get_tag(ph, PTT_AC_NAME))) { 
 1736                                 insert_tag(sp, tag);    /* return it */
 1737                                 send_acname(sp, tag);
 1738                         }
 1739                         if ((tag = get_tag(ph, PTT_MAX_PAYL)) &&
 1740                             (privp->max_payload.data != 0))
 1741                                 insert_tag(sp, tag);    /* return it */
 1742                         insert_tag(sp, &neg->service.hdr); /* Service */
 1743                         scan_tags(sp, ph);
 1744                         make_packet(sp);
 1745                         sp->state = PPPOE_SREQ;
 1746                         ng_callout(&neg->handle, node, sp->hook,
 1747                             PPPOE_INITIAL_TIMEOUT * hz,
 1748                             pppoe_ticker, NULL, 0);
 1749                         neg->timeout = PPPOE_INITIAL_TIMEOUT * 2;
 1750                         m0 = m_copypacket(neg->m, M_NOWAIT);
 1751                         NG_FWD_NEW_DATA(error, item, privp->ethernet_hook, m0);
 1752                         break;
 1753                 case    PADR_CODE:
 1754                         /*
 1755                          * We are a server:
 1756                          * Use the ac_cookie tag to find the
 1757                          * hook this is in response to.
 1758                          */
 1759                         utag = get_tag(ph, PTT_AC_COOKIE);
 1760                         if ((utag == NULL) ||
 1761                             (ntohs(utag->tag_len) != sizeof(sp))) {
 1762                                 LEAVE(ENETUNREACH);
 1763                         }
 1764 
 1765                         sendhook = pppoe_findcookie(node, utag);
 1766                         if (sendhook == NULL)
 1767                                 LEAVE(ENETUNREACH);
 1768 
 1769                         /*
 1770                          * Check the session is in the right state.
 1771                          * It needs to be in PPPOE_SOFFER or PPPOE_NEWCONNECTED.
 1772                          * If the latter, then this is a retry by the client,
 1773                          * so be nice, and resend.
 1774                          */
 1775                         sp = NG_HOOK_PRIVATE(sendhook);
 1776                         if (sp->state == PPPOE_NEWCONNECTED) {
 1777                                 /*
 1778                                  * Whoa! drop back to resend that PADS packet.
 1779                                  * We should still have a copy of it.
 1780                                  */
 1781                                 sp->state = PPPOE_SOFFER;
 1782                         } else if (sp->state != PPPOE_SOFFER)
 1783                                 LEAVE (ENETUNREACH);
 1784                         neg = sp->neg;
 1785                         ng_uncallout(&neg->handle, node);
 1786                         neg->pkt->pkt_header.ph.code = PADS_CODE;
 1787                         if (sp->Session_ID == 0) {
 1788                                 neg->pkt->pkt_header.ph.sid =
 1789                                     htons(pppoe_getnewsession(sp));
 1790                         }
 1791                         send_sessionid(sp);
 1792                         neg->timeout = 0;
 1793                         /*
 1794                          * start working out the tags to respond with.
 1795                          */
 1796                         init_tags(sp);
 1797                         insert_tag(sp, &neg->ac_name.hdr); /* AC_NAME */
 1798                         if ((tag = get_tag(ph, PTT_SRV_NAME)))
 1799                                 insert_tag(sp, tag);/* return service */
 1800                         if ((tag = get_tag(ph, PTT_HOST_UNIQ)))
 1801                                 insert_tag(sp, tag); /* return it */
 1802                         insert_tag(sp, utag);   /* ac_cookie */
 1803                         scan_tags(sp, ph);
 1804                         make_packet(sp);
 1805                         sp->state = PPPOE_NEWCONNECTED;
 1806 
 1807                         /* Send the PADS without a timeout - we're now connected. */
 1808                         m0 = m_copypacket(sp->neg->m, M_NOWAIT);
 1809                         NG_FWD_NEW_DATA(error, item, privp->ethernet_hook, m0);
 1810 
 1811                         /*
 1812                          * Having sent the last Negotiation header,
 1813                          * Set up the stored packet header to be correct for
 1814                          * the actual session. But keep the negotialtion stuff
 1815                          * around in case we need to resend this last packet.
 1816                          * We'll discard it when we move from NEWCONNECTED
 1817                          * to CONNECTED
 1818                          */
 1819                         sp->pkt_hdr = neg->pkt->pkt_header;
 1820                         /* Configure ethertype depending on what
 1821                          * ethertype was used at discovery phase */
 1822                         if (sp->pkt_hdr.eh.ether_type ==
 1823                             ETHERTYPE_PPPOE_3COM_DISC)
 1824                                 sp->pkt_hdr.eh.ether_type
 1825                                         = ETHERTYPE_PPPOE_3COM_SESS;
 1826                         else
 1827                                 sp->pkt_hdr.eh.ether_type
 1828                                         = ETHERTYPE_PPPOE_SESS;
 1829                         sp->pkt_hdr.ph.code = 0;
 1830                         pppoe_send_event(sp, NGM_PPPOE_SUCCESS);
 1831                         break;
 1832                 case    PADS_CODE:
 1833                         /*
 1834                          * We are a client:
 1835                          * Use the host_uniq tag to find the hook this is in
 1836                          * response to. Take the session ID and store it away.
 1837                          * Also make sure the pre-made header is correct and
 1838                          * set us into Session mode.
 1839                          */
 1840                         utag = get_tag(ph, PTT_HOST_UNIQ);
 1841                         if (utag == NULL) {
 1842                                 LEAVE (ENETUNREACH);
 1843                         }
 1844                         sendhook = pppoe_finduniq(node, utag);
 1845                         if (sendhook == NULL)
 1846                                 LEAVE(ENETUNREACH);
 1847 
 1848                         /*
 1849                          * Check the session is in the right state.
 1850                          * It needs to be in PPPOE_SREQ.
 1851                          */
 1852                         sp = NG_HOOK_PRIVATE(sendhook);
 1853                         if (sp->state != PPPOE_SREQ)
 1854                                 LEAVE(ENETUNREACH);
 1855                         neg = sp->neg;
 1856                         ng_uncallout(&neg->handle, node);
 1857                         neg->pkt->pkt_header.ph.sid = wh->ph.sid;
 1858                         sp->Session_ID = ntohs(wh->ph.sid);
 1859                         pppoe_addsession(sp);
 1860                         send_sessionid(sp);
 1861                         neg->timeout = 0;
 1862                         sp->state = PPPOE_CONNECTED;
 1863                         /*
 1864                          * Now we have gone to Connected mode,
 1865                          * Free all resources needed for negotiation.
 1866                          * Keep a copy of the header we will be using.
 1867                          */
 1868                         sp->pkt_hdr = neg->pkt->pkt_header;
 1869                         if (privp->flags & COMPAT_3COM)
 1870                                 sp->pkt_hdr.eh.ether_type
 1871                                         = ETHERTYPE_PPPOE_3COM_SESS;
 1872                         else
 1873                                 sp->pkt_hdr.eh.ether_type
 1874                                         = ETHERTYPE_PPPOE_SESS;
 1875                         sp->pkt_hdr.ph.code = 0;
 1876                         m_freem(neg->m);
 1877                         free(sp->neg, M_NETGRAPH_PPPOE);
 1878                         sp->neg = NULL;
 1879                         if ((tag = get_tag(ph, PTT_MAX_PAYL)) &&
 1880                             (privp->max_payload.data != 0))
 1881                                 send_maxp(sp, tag);
 1882                         pppoe_send_event(sp, NGM_PPPOE_SUCCESS);
 1883                         break;
 1884                 case    PADT_CODE:
 1885                         /*
 1886                          * Find matching peer/session combination.
 1887                          */
 1888                         sp = pppoe_findsession(privp, wh);
 1889                         if (sp == NULL)
 1890                                 LEAVE(ENETUNREACH);
 1891                         /* Disconnect that hook. */
 1892                         ng_rmhook_self(sp->hook);
 1893                         break;
 1894                 case    PADM_CODE:
 1895                         /*
 1896                          * We are a client:
 1897                          * find matching peer/session combination.
 1898                          */
 1899                         sp = pppoe_findsession(privp, wh);
 1900                         if (sp == NULL)
 1901                                 LEAVE (ENETUNREACH);
 1902                         if ((tag = get_tag(ph, PTT_HURL)))
 1903                                 send_hurl(sp, tag);
 1904                         if ((tag = get_tag(ph, PTT_MOTM)))
 1905                                 send_motm(sp, tag);
 1906                         break;
 1907                 default:
 1908                         LEAVE(EPFNOSUPPORT);
 1909                 }
 1910                 break;
 1911         case    ETHERTYPE_PPPOE_3COM_SESS:
 1912         case    ETHERTYPE_PPPOE_SESS:
 1913                 /*
 1914                  * Find matching peer/session combination.
 1915                  */
 1916                 sp = pppoe_findsession(privp, wh);
 1917                 if (sp == NULL)
 1918                         LEAVE (ENETUNREACH);
 1919                 m_adj(m, sizeof(*wh));
 1920 
 1921                 /* If packet too short, dump it. */
 1922                 if (m->m_pkthdr.len < length)
 1923                         LEAVE(EMSGSIZE);
 1924                 /* Also need to trim excess at the end */
 1925                 if (m->m_pkthdr.len > length) {
 1926                         m_adj(m, -((int)(m->m_pkthdr.len - length)));
 1927                 }
 1928                 if ( sp->state != PPPOE_CONNECTED) {
 1929                         if (sp->state == PPPOE_NEWCONNECTED) {
 1930                                 sp->state = PPPOE_CONNECTED;
 1931                                 /*
 1932                                  * Now we have gone to Connected mode,
 1933                                  * Free all resources needed for negotiation.
 1934                                  * Be paranoid about whether there may be
 1935                                  * a timeout.
 1936                                  */
 1937                                 m_freem(sp->neg->m);
 1938                                 ng_uncallout(&sp->neg->handle, node);
 1939                                 free(sp->neg, M_NETGRAPH_PPPOE);
 1940                                 sp->neg = NULL;
 1941                         } else {
 1942                                 LEAVE (ENETUNREACH);
 1943                         }
 1944                 }
 1945                 NG_FWD_NEW_DATA(error, item, sp->hook, m);
 1946                 break;
 1947         default:
 1948                 LEAVE(EPFNOSUPPORT);
 1949         }
 1950 quit:
 1951         if (item)
 1952                 NG_FREE_ITEM(item);
 1953         NG_FREE_M(m);
 1954         return (error);
 1955 }
 1956 
 1957 /*
 1958  * Receive data from debug hook and bypass it to ether.
 1959  */
 1960 static int
 1961 ng_pppoe_rcvdata_debug(hook_p hook, item_p item)
 1962 {
 1963         node_p          node = NG_HOOK_NODE(hook);
 1964         const priv_p    privp = NG_NODE_PRIVATE(node);
 1965         int             error;
 1966 
 1967         CTR6(KTR_NET, "%20s: node [%x] (%p) received %p on \"%s\" (%p)",
 1968             __func__, node->nd_ID, node, item, hook->hk_name, hook);
 1969 
 1970         NG_FWD_ITEM_HOOK(error, item, privp->ethernet_hook);
 1971         privp->packets_out++;
 1972         return (error);
 1973 }
 1974 
 1975 /*
 1976  * Do local shutdown processing..
 1977  * If we are a persistent device, we might refuse to go away, and
 1978  * we'd only remove our links and reset ourself.
 1979  */
 1980 static int
 1981 ng_pppoe_shutdown(node_p node)
 1982 {
 1983         const priv_p privp = NG_NODE_PRIVATE(node);
 1984         int     i;
 1985 
 1986         for (i = 0; i < SESSHASHSIZE; i++)
 1987             mtx_destroy(&privp->sesshash[i].mtx);
 1988         NG_NODE_SET_PRIVATE(node, NULL);
 1989         NG_NODE_UNREF(privp->node);
 1990         free(privp, M_NETGRAPH_PPPOE);
 1991         return (0);
 1992 }
 1993 
 1994 /*
 1995  * Hook disconnection
 1996  *
 1997  * Clean up all dangling links and information about the session/hook.
 1998  * For this type, removal of the last link destroys the node.
 1999  */
 2000 static int
 2001 ng_pppoe_disconnect(hook_p hook)
 2002 {
 2003         node_p node = NG_HOOK_NODE(hook);
 2004         priv_p privp = NG_NODE_PRIVATE(node);
 2005         sessp   sp;
 2006 
 2007         if (hook == privp->debug_hook) {
 2008                 privp->debug_hook = NULL;
 2009         } else if (hook == privp->ethernet_hook) {
 2010                 privp->ethernet_hook = NULL;
 2011                 if (NG_NODE_IS_VALID(node))
 2012                         ng_rmnode_self(node);
 2013         } else {
 2014                 sp = NG_HOOK_PRIVATE(hook);
 2015                 if (sp->state != PPPOE_SNONE ) {
 2016                         pppoe_send_event(sp, NGM_PPPOE_CLOSE);
 2017                 }
 2018                 /*
 2019                  * According to the spec, if we are connected,
 2020                  * we should send a DISC packet if we are shutting down
 2021                  * a session.
 2022                  */
 2023                 if ((privp->ethernet_hook)
 2024                 && ((sp->state == PPPOE_CONNECTED)
 2025                  || (sp->state == PPPOE_NEWCONNECTED))) {
 2026                         struct mbuf *m;
 2027 
 2028                         /* Generate a packet of that type. */
 2029                         m = m_gethdr(M_NOWAIT, MT_DATA);
 2030                         if (m == NULL)
 2031                                 log(LOG_NOTICE, "ng_pppoe[%x]: session out of "
 2032                                     "mbufs\n", node->nd_ID);
 2033                         else {
 2034                                 struct pppoe_full_hdr *wh;
 2035                                 struct pppoe_tag *tag;
 2036                                 int     msglen = strlen(SIGNOFF);
 2037                                 int     error = 0;
 2038 
 2039                                 wh = mtod(m, struct pppoe_full_hdr *);
 2040                                 bcopy(&sp->pkt_hdr, wh, sizeof(*wh));
 2041 
 2042                                 /* Revert the stored header to DISC/PADT mode. */
 2043                                 wh->ph.code = PADT_CODE;
 2044                                 /*
 2045                                  * Configure ethertype depending on what
 2046                                  * was used during sessions stage.
 2047                                  */
 2048                                 if (wh->eh.ether_type == 
 2049                                     ETHERTYPE_PPPOE_3COM_SESS)
 2050                                         wh->eh.ether_type = ETHERTYPE_PPPOE_3COM_DISC;
 2051                                 else
 2052                                         wh->eh.ether_type = ETHERTYPE_PPPOE_DISC;
 2053                                 /*
 2054                                  * Add a General error message and adjust
 2055                                  * sizes.
 2056                                  */
 2057                                 tag = (void *)(&wh->ph + 1);
 2058                                 tag->tag_type = PTT_GEN_ERR;
 2059                                 tag->tag_len = htons((u_int16_t)msglen);
 2060                                 strncpy((char *)(tag + 1), SIGNOFF, msglen);
 2061                                 m->m_pkthdr.len = m->m_len = sizeof(*wh) + sizeof(*tag) +
 2062                                     msglen;
 2063                                 wh->ph.length = htons(sizeof(*tag) + msglen);
 2064                                 NG_SEND_DATA_ONLY(error,
 2065                                         privp->ethernet_hook, m);
 2066                         }
 2067                 }
 2068                 if (sp->state == PPPOE_LISTENING)
 2069                         LIST_REMOVE(sp, sessions);
 2070                 else if (sp->Session_ID)
 2071                         pppoe_delsession(sp);
 2072                 /*
 2073                  * As long as we have somewhere to store the timeout handle,
 2074                  * we may have a timeout pending.. get rid of it.
 2075                  */
 2076                 if (sp->neg) {
 2077                         ng_uncallout(&sp->neg->handle, node);
 2078                         if (sp->neg->m)
 2079                                 m_freem(sp->neg->m);
 2080                         free(sp->neg, M_NETGRAPH_PPPOE);
 2081                 }
 2082                 free(sp, M_NETGRAPH_PPPOE);
 2083                 NG_HOOK_SET_PRIVATE(hook, NULL);
 2084         }
 2085         if ((NG_NODE_NUMHOOKS(node) == 0) &&
 2086             (NG_NODE_IS_VALID(node)))
 2087                 ng_rmnode_self(node);
 2088         return (0);
 2089 }
 2090 
 2091 /*
 2092  * Timeouts come here.
 2093  */
 2094 static void
 2095 pppoe_ticker(node_p node, hook_p hook, void *arg1, int arg2)
 2096 {
 2097         priv_p privp = NG_NODE_PRIVATE(NG_HOOK_NODE(hook));
 2098         sessp   sp = NG_HOOK_PRIVATE(hook);
 2099         negp    neg = sp->neg;
 2100         struct mbuf *m0 = NULL;
 2101         int     error = 0;
 2102 
 2103         CTR6(KTR_NET, "%20s: node [%x] (%p) hook \"%s\" (%p) session %d",
 2104             __func__, node->nd_ID, node, hook->hk_name, hook, sp->Session_ID);
 2105         switch(sp->state) {
 2106                 /*
 2107                  * Resend the last packet, using an exponential backoff.
 2108                  * After a period of time, stop growing the backoff,
 2109                  * And either leave it, or revert to the start.
 2110                  */
 2111         case    PPPOE_SINIT:
 2112         case    PPPOE_SREQ:
 2113                 /* Timeouts on these produce resends. */
 2114                 m0 = m_copypacket(sp->neg->m, M_NOWAIT);
 2115                 NG_SEND_DATA_ONLY( error, privp->ethernet_hook, m0);
 2116                 ng_callout(&neg->handle, node, hook, neg->timeout * hz,
 2117                     pppoe_ticker, NULL, 0);
 2118                 if ((neg->timeout <<= 1) > PPPOE_TIMEOUT_LIMIT) {
 2119                         if (sp->state == PPPOE_SREQ) {
 2120                                 /* Revert to SINIT mode. */
 2121                                 pppoe_start(sp);
 2122                         } else {
 2123                                 neg->timeout = PPPOE_TIMEOUT_LIMIT;
 2124                         }
 2125                 }
 2126                 break;
 2127         case    PPPOE_PRIMED:
 2128         case    PPPOE_SOFFER:
 2129                 /* A timeout on these says "give up" */
 2130                 ng_rmhook_self(hook);
 2131                 break;
 2132         default:
 2133                 /* Timeouts have no meaning in other states. */
 2134                 log(LOG_NOTICE, "ng_pppoe[%x]: unexpected timeout\n",
 2135                     node->nd_ID);
 2136         }
 2137 }
 2138 
 2139 /*
 2140  * Parse an incoming packet to see if any tags should be copied to the
 2141  * output packet. Don't do any tags that have been handled in the main
 2142  * state machine.
 2143  */
 2144 static const struct pppoe_tag*
 2145 scan_tags(sessp sp, const struct pppoe_hdr* ph)
 2146 {
 2147         const char *const end = (const char *)next_tag(ph);
 2148         const char *ptn;
 2149         const struct pppoe_tag *pt = (const void *)(ph + 1);
 2150 
 2151         /*
 2152          * Keep processing tags while a tag header will still fit.
 2153          */
 2154         CTR2(KTR_NET, "%20s: called %d", __func__, sp->Session_ID);
 2155 
 2156         while((const char*)(pt + 1) <= end) {
 2157                 /*
 2158                  * If the tag data would go past the end of the packet, abort.
 2159                  */
 2160                 ptn = (((const char *)(pt + 1)) + ntohs(pt->tag_len));
 2161                 if(ptn > end)
 2162                         return NULL;
 2163 
 2164                 switch (pt->tag_type) {
 2165                 case    PTT_RELAY_SID:
 2166                         insert_tag(sp, pt);
 2167                         break;
 2168                 case    PTT_EOL:
 2169                         return NULL;
 2170                 case    PTT_SRV_NAME:
 2171                 case    PTT_AC_NAME:
 2172                 case    PTT_HOST_UNIQ:
 2173                 case    PTT_AC_COOKIE:
 2174                 case    PTT_VENDOR:
 2175                 case    PTT_SRV_ERR:
 2176                 case    PTT_SYS_ERR:
 2177                 case    PTT_GEN_ERR:
 2178                 case    PTT_MAX_PAYL:
 2179                 case    PTT_HURL:
 2180                 case    PTT_MOTM:
 2181                         break;
 2182                 }
 2183                 pt = (const struct pppoe_tag*)ptn;
 2184         }
 2185         return NULL;
 2186 }
 2187         
 2188 static  int
 2189 pppoe_send_event(sessp sp, enum cmd cmdid)
 2190 {
 2191         int error;
 2192         struct ng_mesg *msg;
 2193         struct ngpppoe_sts *sts;
 2194 
 2195         CTR2(KTR_NET, "%20s: called %d", __func__, sp->Session_ID);
 2196 
 2197         NG_MKMESSAGE(msg, NGM_PPPOE_COOKIE, cmdid,
 2198                         sizeof(struct ngpppoe_sts), M_NOWAIT);
 2199         if (msg == NULL)
 2200                 return (ENOMEM);
 2201         sts = (struct ngpppoe_sts *)msg->data;
 2202         strncpy(sts->hook, NG_HOOK_NAME(sp->hook), NG_HOOKSIZ);
 2203         NG_SEND_MSG_ID(error, NG_HOOK_NODE(sp->hook), msg, sp->creator, 0);
 2204         return (error);
 2205 }

Cache object: e913122f9e2081157cecef549dd3786a


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