1 /*****************************************************************************
2 * pppoe.c - PPP Over Ethernet implementation for lwIP.
3 *
4 * Copyright (c) 2006 by Marc Boucher, Services Informatiques (MBSI) inc.
5 *
6 * The authors hereby grant permission to use, copy, modify, distribute,
7 * and license this software and its documentation for any purpose, provided
8 * that existing copyright notices are retained in all copies and that this
9 * notice and the following disclaimer are included verbatim in any
10 * distributions. No written agreement, license, or royalty fee is required
11 * for any of the authorized uses.
12 *
13 * THIS SOFTWARE IS PROVIDED BY THE CONTRIBUTORS *AS IS* AND ANY EXPRESS OR
14 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
15 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
16 * IN NO EVENT SHALL THE CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
17 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
18 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
19 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
20 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
21 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
22 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
23 *
24 ******************************************************************************
25 * REVISION HISTORY
26 *
27 * 06-01-01 Marc Boucher <marc@mbsi.ca>
28 *   Ported to lwIP.
29 *****************************************************************************/
30 
31 
32 
33 /* based on NetBSD: if_pppoe.c,v 1.64 2006/01/31 23:50:15 martin Exp */
34 
35 /*-
36  * Copyright (c) 2002 The NetBSD Foundation, Inc.
37  * All rights reserved.
38  *
39  * This code is derived from software contributed to The NetBSD Foundation
40  * by Martin Husemann <martin@NetBSD.org>.
41  *
42  * Redistribution and use in source and binary forms, with or without
43  * modification, are permitted provided that the following conditions
44  * are met:
45  * 1. Redistributions of source code must retain the above copyright
46  *    notice, this list of conditions and the following disclaimer.
47  * 2. Redistributions in binary form must reproduce the above copyright
48  *    notice, this list of conditions and the following disclaimer in the
49  *    documentation and/or other materials provided with the distribution.
50  * 3. All advertising materials mentioning features or use of this software
51  *    must display the following acknowledgement:
52  *        This product includes software developed by the NetBSD
53  *        Foundation, Inc. and its contributors.
54  * 4. Neither the name of The NetBSD Foundation nor the names of its
55  *    contributors may be used to endorse or promote products derived
56  *    from this software without specific prior written permission.
57  *
58  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
59  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
60  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
61  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
62  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
63  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
64  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
65  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
66  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
67  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
68  * POSSIBILITY OF SUCH DAMAGE.
69  */
70 
71 #include "netif/ppp/ppp_opts.h"
72 #if PPP_SUPPORT && PPPOE_SUPPORT /* don't build if not configured for use in lwipopts.h */
73 
74 #if 0 /* UNUSED */
75 #include <string.h>
76 #include <stdio.h>
77 #endif /* UNUSED */
78 
79 #include "lwip/timeouts.h"
80 #include "lwip/memp.h"
81 #include "lwip/stats.h"
82 #include "lwip/snmp.h"
83 
84 #include "netif/ethernet.h"
85 #include "netif/ppp/ppp_impl.h"
86 #include "netif/ppp/lcp.h"
87 #include "netif/ppp/ipcp.h"
88 #include "netif/ppp/pppoe.h"
89 
90 /* Memory pool */
91 LWIP_MEMPOOL_DECLARE(PPPOE_IF, MEMP_NUM_PPPOE_INTERFACES, sizeof(struct pppoe_softc), "PPPOE_IF")
92 
93 /* Add a 16 bit unsigned value to a buffer pointed to by PTR */
94 #define PPPOE_ADD_16(PTR, VAL) \
95     *(PTR)++ = (u8_t)((VAL) / 256);    \
96     *(PTR)++ = (u8_t)((VAL) % 256)
97 
98 /* Add a complete PPPoE header to the buffer pointed to by PTR */
99 #define PPPOE_ADD_HEADER(PTR, CODE, SESS, LEN)  \
100     *(PTR)++ = PPPOE_VERTYPE;  \
101     *(PTR)++ = (CODE);         \
102     PPPOE_ADD_16(PTR, SESS);   \
103     PPPOE_ADD_16(PTR, LEN)
104 
105 #define PPPOE_DISC_TIMEOUT (5*1000)  /* base for quick timeout calculation */
106 #define PPPOE_SLOW_RETRY   (60*1000) /* persistent retry interval */
107 #define PPPOE_DISC_MAXPADI  4        /* retry PADI four times (quickly) */
108 #define PPPOE_DISC_MAXPADR  2        /* retry PADR twice */
109 
110 #ifdef PPPOE_SERVER
111 #error "PPPOE_SERVER is not yet supported under lwIP!"
112 /* from if_spppsubr.c */
113 #define IFF_PASSIVE IFF_LINK0 /* wait passively for connection */
114 #endif
115 
116 #define PPPOE_ERRORSTRING_LEN     64
117 
118 
119 /* callbacks called from PPP core */
120 static err_t pppoe_write(ppp_pcb *ppp, void *ctx, struct pbuf *p);
121 static err_t pppoe_netif_output(ppp_pcb *ppp, void *ctx, struct pbuf *p, u_short protocol);
122 static void pppoe_connect(ppp_pcb *ppp, void *ctx);
123 static void pppoe_disconnect(ppp_pcb *ppp, void *ctx);
124 static err_t pppoe_destroy(ppp_pcb *ppp, void *ctx);
125 
126 /* management routines */
127 static void pppoe_abort_connect(struct pppoe_softc *);
128 #if 0 /* UNUSED */
129 static void pppoe_clear_softc(struct pppoe_softc *, const char *);
130 #endif /* UNUSED */
131 
132 /* internal timeout handling */
133 static void pppoe_timeout(void *);
134 
135 /* sending actual protocol control packets */
136 static err_t pppoe_send_padi(struct pppoe_softc *);
137 static err_t pppoe_send_padr(struct pppoe_softc *);
138 #ifdef PPPOE_SERVER
139 static err_t pppoe_send_pado(struct pppoe_softc *);
140 static err_t pppoe_send_pads(struct pppoe_softc *);
141 #endif
142 static err_t pppoe_send_padt(struct netif *, u_int, const u8_t *);
143 
144 /* internal helper functions */
145 static err_t pppoe_xmit(struct pppoe_softc *sc, struct pbuf *pb);
146 static struct pppoe_softc* pppoe_find_softc_by_session(u_int session, struct netif *rcvif);
147 static struct pppoe_softc* pppoe_find_softc_by_hunique(u8_t *token, size_t len, struct netif *rcvif);
148 
149 /** linked list of created pppoe interfaces */
150 static struct pppoe_softc *pppoe_softc_list;
151 
152 /* Callbacks structure for PPP core */
153 static const struct link_callbacks pppoe_callbacks = {
154   pppoe_connect,
155 #if PPP_SERVER
156   NULL,
157 #endif /* PPP_SERVER */
158   pppoe_disconnect,
159   pppoe_destroy,
160   pppoe_write,
161   pppoe_netif_output,
162   NULL,
163   NULL
164 };
165 
166 /*
167  * Create a new PPP Over Ethernet (PPPoE) connection.
168  *
169  * Return 0 on success, an error code on failure.
170  */
pppoe_create(struct netif * pppif,struct netif * ethif,const char * service_name,const char * concentrator_name,ppp_link_status_cb_fn link_status_cb,void * ctx_cb)171 ppp_pcb *pppoe_create(struct netif *pppif,
172        struct netif *ethif,
173        const char *service_name, const char *concentrator_name,
174        ppp_link_status_cb_fn link_status_cb, void *ctx_cb)
175 {
176   ppp_pcb *ppp;
177   struct pppoe_softc *sc;
178 #if PPPOE_SCNAME_SUPPORT
179   size_t l;
180 #else /* PPPOE_SCNAME_SUPPORT */
181   LWIP_UNUSED_ARG(service_name);
182   LWIP_UNUSED_ARG(concentrator_name);
183 #endif /* PPPOE_SCNAME_SUPPORT */
184   LWIP_ASSERT_CORE_LOCKED();
185 
186 #if PPPOE_SCNAME_SUPPORT
187   /*
188    * Check that service_name and concentrator_name strings length will
189    * not trigger integer overflows when computing packets length.
190    */
191   l = strlen(service_name);
192   if (l > 1024) {
193     return NULL;
194   }
195   l = strlen(concentrator_name);
196   if (l > 1024) {
197     return NULL;
198   }
199 #endif /* PPPOE_SCNAME_SUPPORT */
200 
201   sc = (struct pppoe_softc *)LWIP_MEMPOOL_ALLOC(PPPOE_IF);
202   if (sc == NULL) {
203     return NULL;
204   }
205 
206   ppp = ppp_new(pppif, &pppoe_callbacks, sc, link_status_cb, ctx_cb);
207   if (ppp == NULL) {
208     LWIP_MEMPOOL_FREE(PPPOE_IF, sc);
209     return NULL;
210   }
211 
212   memset(sc, 0, sizeof(struct pppoe_softc));
213   sc->pcb = ppp;
214   sc->sc_ethif = ethif;
215 #if PPPOE_SCNAME_SUPPORT
216   sc->sc_service_name = service_name;
217   sc->sc_concentrator_name = concentrator_name;
218 #endif /* PPPOE_SCNAME_SUPPORT */
219   /* put the new interface at the head of the list */
220   sc->next = pppoe_softc_list;
221   pppoe_softc_list = sc;
222   return ppp;
223 }
224 
225 /* Called by PPP core */
pppoe_write(ppp_pcb * ppp,void * ctx,struct pbuf * p)226 static err_t pppoe_write(ppp_pcb *ppp, void *ctx, struct pbuf *p) {
227   struct pppoe_softc *sc = (struct pppoe_softc *)ctx;
228   struct pbuf *ph; /* Ethernet + PPPoE header */
229   err_t ret;
230 #if MIB2_STATS
231   u16_t tot_len;
232 #else /* MIB2_STATS */
233   LWIP_UNUSED_ARG(ppp);
234 #endif /* MIB2_STATS */
235 
236   /* skip address & flags */
237   pbuf_remove_header(p, 2);
238 
239   ph = pbuf_alloc(PBUF_LINK, (u16_t)(PPPOE_HEADERLEN), PBUF_RAM);
240   if(!ph) {
241     LINK_STATS_INC(link.memerr);
242     LINK_STATS_INC(link.proterr);
243     MIB2_STATS_NETIF_INC(ppp->netif, ifoutdiscards);
244     pbuf_free(p);
245     return ERR_MEM;
246   }
247 
248   pbuf_remove_header(ph, PPPOE_HEADERLEN); /* hide PPPoE header */
249   pbuf_cat(ph, p);
250 #if MIB2_STATS
251   tot_len = ph->tot_len;
252 #endif /* MIB2_STATS */
253 
254   ret = pppoe_xmit(sc, ph);
255   if (ret != ERR_OK) {
256     LINK_STATS_INC(link.err);
257     MIB2_STATS_NETIF_INC(ppp->netif, ifoutdiscards);
258     return ret;
259   }
260 
261   MIB2_STATS_NETIF_ADD(ppp->netif, ifoutoctets, (u16_t)tot_len);
262   MIB2_STATS_NETIF_INC(ppp->netif, ifoutucastpkts);
263   LINK_STATS_INC(link.xmit);
264   return ERR_OK;
265 }
266 
267 /* Called by PPP core */
pppoe_netif_output(ppp_pcb * ppp,void * ctx,struct pbuf * p,u_short protocol)268 static err_t pppoe_netif_output(ppp_pcb *ppp, void *ctx, struct pbuf *p, u_short protocol) {
269   struct pppoe_softc *sc = (struct pppoe_softc *)ctx;
270   struct pbuf *pb;
271   u8_t *pl;
272   err_t err;
273 #if MIB2_STATS
274   u16_t tot_len;
275 #else /* MIB2_STATS */
276   LWIP_UNUSED_ARG(ppp);
277 #endif /* MIB2_STATS */
278 
279   /* @todo: try to use pbuf_header() here! */
280   pb = pbuf_alloc(PBUF_LINK, PPPOE_HEADERLEN + sizeof(protocol), PBUF_RAM);
281   if(!pb) {
282     LINK_STATS_INC(link.memerr);
283     LINK_STATS_INC(link.proterr);
284     MIB2_STATS_NETIF_INC(ppp->netif, ifoutdiscards);
285     return ERR_MEM;
286   }
287 
288   pbuf_remove_header(pb, PPPOE_HEADERLEN);
289 
290   pl = (u8_t*)pb->payload;
291   PUTSHORT(protocol, pl);
292 
293   pbuf_chain(pb, p);
294 #if MIB2_STATS
295   tot_len = pb->tot_len;
296 #endif /* MIB2_STATS */
297 
298   if( (err = pppoe_xmit(sc, pb)) != ERR_OK) {
299     LINK_STATS_INC(link.err);
300     MIB2_STATS_NETIF_INC(ppp->netif, ifoutdiscards);
301     return err;
302   }
303 
304   MIB2_STATS_NETIF_ADD(ppp->netif, ifoutoctets, tot_len);
305   MIB2_STATS_NETIF_INC(ppp->netif, ifoutucastpkts);
306   LINK_STATS_INC(link.xmit);
307   return ERR_OK;
308 }
309 
310 static err_t
pppoe_destroy(ppp_pcb * ppp,void * ctx)311 pppoe_destroy(ppp_pcb *ppp, void *ctx)
312 {
313   struct pppoe_softc *sc = (struct pppoe_softc *)ctx;
314   struct pppoe_softc **copp, *freep;
315   LWIP_UNUSED_ARG(ppp);
316 
317   sys_untimeout(pppoe_timeout, sc);
318 
319   /* remove interface from list */
320   for (copp = &pppoe_softc_list; (freep = *copp); copp = &freep->next) {
321     if (freep == sc) {
322        *copp = freep->next;
323        break;
324     }
325   }
326   LWIP_MEMPOOL_FREE(PPPOE_IF, sc);
327 
328   return ERR_OK;
329 }
330 
331 /*
332  * Find the interface handling the specified session.
333  * Note: O(number of sessions open), this is a client-side only, mean
334  * and lean implementation, so number of open sessions typically should
335  * be 1.
336  */
pppoe_find_softc_by_session(u_int session,struct netif * rcvif)337 static struct pppoe_softc* pppoe_find_softc_by_session(u_int session, struct netif *rcvif) {
338   struct pppoe_softc *sc;
339 
340   for (sc = pppoe_softc_list; sc != NULL; sc = sc->next) {
341     if (sc->sc_state == PPPOE_STATE_SESSION
342         && sc->sc_session == session
343          && sc->sc_ethif == rcvif) {
344            return sc;
345       }
346   }
347   return NULL;
348 }
349 
350 /* Check host unique token passed and return appropriate softc pointer,
351  * or NULL if token is bogus. */
pppoe_find_softc_by_hunique(u8_t * token,size_t len,struct netif * rcvif)352 static struct pppoe_softc* pppoe_find_softc_by_hunique(u8_t *token, size_t len, struct netif *rcvif) {
353   struct pppoe_softc *sc, *t;
354 
355   if (len != sizeof sc) {
356     return NULL;
357   }
358   MEMCPY(&t, token, len);
359 
360   for (sc = pppoe_softc_list; sc != NULL; sc = sc->next) {
361     if (sc == t) {
362       break;
363     }
364   }
365 
366   if (sc == NULL) {
367     PPPDEBUG(LOG_DEBUG, ("pppoe: alien host unique tag, no session found\n"));
368     return NULL;
369   }
370 
371   /* should be safe to access *sc now */
372   if (sc->sc_state < PPPOE_STATE_PADI_SENT || sc->sc_state >= PPPOE_STATE_SESSION) {
373     PPPDEBUG(LOG_DEBUG, ("%c%c%"U16_F": host unique tag found, but it belongs to a connection in state %d\n",
374       sc->sc_ethif->name[0], sc->sc_ethif->name[1], sc->sc_ethif->num, sc->sc_state));
375     return NULL;
376   }
377   if (sc->sc_ethif != rcvif) {
378     PPPDEBUG(LOG_DEBUG, ("%c%c%"U16_F": wrong interface, not accepting host unique\n",
379       sc->sc_ethif->name[0], sc->sc_ethif->name[1], sc->sc_ethif->num));
380     return NULL;
381   }
382   return sc;
383 }
384 
385 /* analyze and handle a single received packet while not in session state */
386 void
pppoe_disc_input(struct netif * netif,struct pbuf * pb)387 pppoe_disc_input(struct netif *netif, struct pbuf *pb)
388 {
389   u16_t tag, len, off;
390   u16_t session, plen;
391   struct pppoe_softc *sc;
392 #if PPP_DEBUG
393   const char *err_msg = NULL;
394 #endif /* PPP_DEBUG */
395   u8_t *ac_cookie;
396   u16_t ac_cookie_len;
397 #ifdef PPPOE_SERVER
398   u8_t *hunique;
399   size_t hunique_len;
400 #endif
401   struct pppoehdr *ph;
402   struct pppoetag pt;
403   int err;
404   struct eth_hdr *ethhdr;
405 
406   /* don't do anything if there is not a single PPPoE instance */
407   if (pppoe_softc_list == NULL) {
408     pbuf_free(pb);
409     return;
410   }
411 
412   pb = pbuf_coalesce(pb, PBUF_RAW);
413   if (pb->next != NULL) {
414     PPPDEBUG(LOG_DEBUG, ("pppoe: pbuf_coalesce failed: %d\n", pb->tot_len));
415     goto done;
416   }
417 
418   ethhdr = (struct eth_hdr *)pb->payload;
419 
420   ac_cookie = NULL;
421   ac_cookie_len = 0;
422 #ifdef PPPOE_SERVER
423   hunique = NULL;
424   hunique_len = 0;
425 #endif
426   session = 0;
427   off = sizeof(struct eth_hdr) + sizeof(struct pppoehdr);
428   if (pb->len < off) {
429     PPPDEBUG(LOG_DEBUG, ("pppoe: packet too short: %d\n", pb->len));
430     goto done;
431   }
432 
433   ph = (struct pppoehdr *) (ethhdr + 1);
434   if (ph->vertype != PPPOE_VERTYPE) {
435     PPPDEBUG(LOG_DEBUG, ("pppoe: unknown version/type packet: 0x%x\n", ph->vertype));
436     goto done;
437   }
438   session = lwip_ntohs(ph->session);
439   plen = lwip_ntohs(ph->plen);
440 
441   if (plen > (pb->len - off)) {
442     PPPDEBUG(LOG_DEBUG, ("pppoe: packet content does not fit: data available = %d, packet size = %u\n",
443         pb->len - off, plen));
444     goto done;
445   }
446   if(pb->tot_len == pb->len) {
447     u16_t framelen = off + plen;
448     if (framelen < pb->len) {
449       /* ignore trailing garbage */
450       pb->tot_len = pb->len = framelen;
451     }
452   }
453   tag = 0;
454   len = 0;
455   sc = NULL;
456   while (off + sizeof(pt) <= pb->len) {
457     MEMCPY(&pt, (u8_t*)pb->payload + off, sizeof(pt));
458     tag = lwip_ntohs(pt.tag);
459     len = lwip_ntohs(pt.len);
460     if (off + sizeof(pt) + len > pb->len) {
461       PPPDEBUG(LOG_DEBUG, ("pppoe: tag 0x%x len 0x%x is too long\n", tag, len));
462       goto done;
463     }
464     switch (tag) {
465       case PPPOE_TAG_EOL:
466         goto breakbreak;
467       case PPPOE_TAG_SNAME:
468         break;  /* ignored */
469       case PPPOE_TAG_ACNAME:
470         break;  /* ignored */
471       case PPPOE_TAG_HUNIQUE:
472         if (sc != NULL) {
473           break;
474         }
475 #ifdef PPPOE_SERVER
476         hunique = (u8_t*)pb->payload + off + sizeof(pt);
477         hunique_len = len;
478 #endif
479         sc = pppoe_find_softc_by_hunique((u8_t*)pb->payload + off + sizeof(pt), len, netif);
480         break;
481       case PPPOE_TAG_ACCOOKIE:
482         if (ac_cookie == NULL) {
483           if (len > PPPOE_MAX_AC_COOKIE_LEN) {
484             PPPDEBUG(LOG_DEBUG, ("pppoe: AC cookie is too long: len = %d, max = %d\n", len, PPPOE_MAX_AC_COOKIE_LEN));
485             goto done;
486           }
487           ac_cookie = (u8_t*)pb->payload + off + sizeof(pt);
488           ac_cookie_len = len;
489         }
490         break;
491 #if PPP_DEBUG
492       case PPPOE_TAG_SNAME_ERR:
493         err_msg = "SERVICE NAME ERROR";
494         break;
495       case PPPOE_TAG_ACSYS_ERR:
496         err_msg = "AC SYSTEM ERROR";
497         break;
498       case PPPOE_TAG_GENERIC_ERR:
499         err_msg = "GENERIC ERROR";
500         break;
501 #endif /* PPP_DEBUG */
502       default:
503         break;
504     }
505 #if PPP_DEBUG
506     if (err_msg != NULL) {
507       char error_tmp[PPPOE_ERRORSTRING_LEN];
508       u16_t error_len = LWIP_MIN(len, sizeof(error_tmp)-1);
509       strncpy(error_tmp, (char*)pb->payload + off + sizeof(pt), error_len);
510       error_tmp[error_len] = '\0';
511       if (sc) {
512         PPPDEBUG(LOG_DEBUG, ("pppoe: %c%c%"U16_F": %s: %s\n", sc->sc_ethif->name[0], sc->sc_ethif->name[1], sc->sc_ethif->num, err_msg, error_tmp));
513       } else {
514         PPPDEBUG(LOG_DEBUG, ("pppoe: %s: %s\n", err_msg, error_tmp));
515       }
516     }
517 #endif /* PPP_DEBUG */
518     off += sizeof(pt) + len;
519   }
520 
521 breakbreak:;
522   switch (ph->code) {
523     case PPPOE_CODE_PADI:
524 #ifdef PPPOE_SERVER
525       /*
526        * got service name, concentrator name, and/or host unique.
527        * ignore if we have no interfaces with IFF_PASSIVE|IFF_UP.
528        */
529       if (LIST_EMPTY(&pppoe_softc_list)) {
530         goto done;
531       }
532       LIST_FOREACH(sc, &pppoe_softc_list, sc_list) {
533         if (!(sc->sc_sppp.pp_if.if_flags & IFF_UP)) {
534           continue;
535         }
536         if (!(sc->sc_sppp.pp_if.if_flags & IFF_PASSIVE)) {
537           continue;
538         }
539         if (sc->sc_state == PPPOE_STATE_INITIAL) {
540           break;
541         }
542       }
543       if (sc == NULL) {
544         /* PPPDEBUG(LOG_DEBUG, ("pppoe: free passive interface is not found\n")); */
545         goto done;
546       }
547       if (hunique) {
548         if (sc->sc_hunique) {
549           mem_free(sc->sc_hunique);
550         }
551         sc->sc_hunique = mem_malloc(hunique_len);
552         if (sc->sc_hunique == NULL) {
553           goto done;
554         }
555         sc->sc_hunique_len = hunique_len;
556         MEMCPY(sc->sc_hunique, hunique, hunique_len);
557       }
558       MEMCPY(&sc->sc_dest, eh->ether_shost, sizeof sc->sc_dest);
559       sc->sc_state = PPPOE_STATE_PADO_SENT;
560       pppoe_send_pado(sc);
561       break;
562 #endif /* PPPOE_SERVER */
563     case PPPOE_CODE_PADR:
564 #ifdef PPPOE_SERVER
565       /*
566        * get sc from ac_cookie if IFF_PASSIVE
567        */
568       if (ac_cookie == NULL) {
569         /* be quiet if there is not a single pppoe instance */
570         PPPDEBUG(LOG_DEBUG, ("pppoe: received PADR but not includes ac_cookie\n"));
571         goto done;
572       }
573       sc = pppoe_find_softc_by_hunique(ac_cookie, ac_cookie_len, netif);
574       if (sc == NULL) {
575         /* be quiet if there is not a single pppoe instance */
576         if (!LIST_EMPTY(&pppoe_softc_list)) {
577           PPPDEBUG(LOG_DEBUG, ("pppoe: received PADR but could not find request for it\n"));
578         }
579         goto done;
580       }
581       if (sc->sc_state != PPPOE_STATE_PADO_SENT) {
582         PPPDEBUG(LOG_DEBUG, ("%c%c%"U16_F": received unexpected PADR\n", sc->sc_ethif->name[0], sc->sc_ethif->name[1], sc->sc_ethif->num));
583         goto done;
584       }
585       if (hunique) {
586         if (sc->sc_hunique) {
587           mem_free(sc->sc_hunique);
588         }
589         sc->sc_hunique = mem_malloc(hunique_len);
590         if (sc->sc_hunique == NULL) {
591           goto done;
592         }
593         sc->sc_hunique_len = hunique_len;
594         MEMCPY(sc->sc_hunique, hunique, hunique_len);
595       }
596       pppoe_send_pads(sc);
597       sc->sc_state = PPPOE_STATE_SESSION;
598       ppp_start(sc->pcb); /* notify upper layers */
599       break;
600 #else
601       /* ignore, we are no access concentrator */
602       goto done;
603 #endif /* PPPOE_SERVER */
604     case PPPOE_CODE_PADO:
605       if (sc == NULL) {
606         /* be quiet if there is not a single pppoe instance */
607         if (pppoe_softc_list != NULL) {
608           PPPDEBUG(LOG_DEBUG, ("pppoe: received PADO but could not find request for it\n"));
609         }
610         goto done;
611       }
612       if (sc->sc_state != PPPOE_STATE_PADI_SENT) {
613         PPPDEBUG(LOG_DEBUG, ("%c%c%"U16_F": received unexpected PADO\n", sc->sc_ethif->name[0], sc->sc_ethif->name[1], sc->sc_ethif->num));
614         goto done;
615       }
616       if (ac_cookie) {
617         sc->sc_ac_cookie_len = ac_cookie_len;
618         MEMCPY(sc->sc_ac_cookie, ac_cookie, ac_cookie_len);
619       }
620       MEMCPY(&sc->sc_dest, ethhdr->src.addr, sizeof(sc->sc_dest.addr));
621       sys_untimeout(pppoe_timeout, sc);
622       sc->sc_padr_retried = 0;
623       sc->sc_state = PPPOE_STATE_PADR_SENT;
624       if ((err = pppoe_send_padr(sc)) != 0) {
625         PPPDEBUG(LOG_DEBUG, ("pppoe: %c%c%"U16_F": failed to send PADR, error=%d\n", sc->sc_ethif->name[0], sc->sc_ethif->name[1], sc->sc_ethif->num, err));
626         LWIP_UNUSED_ARG(err); /* if PPPDEBUG is disabled */
627       }
628       sys_timeout(PPPOE_DISC_TIMEOUT * (1 + sc->sc_padr_retried), pppoe_timeout, sc);
629       break;
630     case PPPOE_CODE_PADS:
631       if (sc == NULL) {
632         goto done;
633       }
634       sc->sc_session = session;
635       sys_untimeout(pppoe_timeout, sc);
636       PPPDEBUG(LOG_DEBUG, ("pppoe: %c%c%"U16_F": session 0x%x connected\n", sc->sc_ethif->name[0], sc->sc_ethif->name[1], sc->sc_ethif->num, session));
637       sc->sc_state = PPPOE_STATE_SESSION;
638       ppp_start(sc->pcb); /* notify upper layers */
639       break;
640     case PPPOE_CODE_PADT:
641       /* Don't disconnect here, we let the LCP Echo/Reply find the fact
642        * that PPP session is down. Asking the PPP stack to end the session
643        * require strict checking about the PPP phase to prevent endless
644        * disconnection loops.
645        */
646 #if 0 /* UNUSED */
647       if (sc == NULL) { /* PADT frames are rarely sent with a hunique tag, this is actually almost always true */
648         goto done;
649       }
650       pppoe_clear_softc(sc, "received PADT");
651 #endif /* UNUSED */
652       break;
653     default:
654       if(sc) {
655         PPPDEBUG(LOG_DEBUG, ("%c%c%"U16_F": unknown code (0x%"X16_F") session = 0x%"X16_F"\n",
656             sc->sc_ethif->name[0], sc->sc_ethif->name[1], sc->sc_ethif->num,
657             (u16_t)ph->code, session));
658       } else {
659         PPPDEBUG(LOG_DEBUG, ("pppoe: unknown code (0x%"X16_F") session = 0x%"X16_F"\n", (u16_t)ph->code, session));
660       }
661       break;
662   }
663 
664 done:
665   pbuf_free(pb);
666   return;
667 }
668 
669 void
pppoe_data_input(struct netif * netif,struct pbuf * pb)670 pppoe_data_input(struct netif *netif, struct pbuf *pb)
671 {
672   u16_t session, plen;
673   struct pppoe_softc *sc;
674   struct pppoehdr *ph;
675 #ifdef PPPOE_TERM_UNKNOWN_SESSIONS
676   u8_t shost[ETHER_ADDR_LEN];
677 #endif
678 
679 #ifdef PPPOE_TERM_UNKNOWN_SESSIONS
680   MEMCPY(shost, ((struct eth_hdr *)pb->payload)->src.addr, sizeof(shost));
681 #endif
682   if (pbuf_remove_header(pb, sizeof(struct eth_hdr)) != 0) {
683     /* bail out */
684     PPPDEBUG(LOG_ERR, ("pppoe_data_input: pbuf_remove_header failed\n"));
685     LINK_STATS_INC(link.lenerr);
686     goto drop;
687   }
688 
689   if (pb->len < sizeof(*ph)) {
690     PPPDEBUG(LOG_DEBUG, ("pppoe_data_input: could not get PPPoE header\n"));
691     goto drop;
692   }
693   ph = (struct pppoehdr *)pb->payload;
694 
695   if (ph->vertype != PPPOE_VERTYPE) {
696     PPPDEBUG(LOG_DEBUG, ("pppoe (data): unknown version/type packet: 0x%x\n", ph->vertype));
697     goto drop;
698   }
699   if (ph->code != 0) {
700     goto drop;
701   }
702 
703   session = lwip_ntohs(ph->session);
704   sc = pppoe_find_softc_by_session(session, netif);
705   if (sc == NULL) {
706 #ifdef PPPOE_TERM_UNKNOWN_SESSIONS
707     PPPDEBUG(LOG_DEBUG, ("pppoe: input for unknown session 0x%x, sending PADT\n", session));
708     pppoe_send_padt(netif, session, shost);
709 #endif
710     goto drop;
711   }
712 
713   plen = lwip_ntohs(ph->plen);
714 
715   if (pbuf_remove_header(pb, PPPOE_HEADERLEN) != 0) {
716     /* bail out */
717     PPPDEBUG(LOG_ERR, ("pppoe_data_input: pbuf_remove_header PPPOE_HEADERLEN failed\n"));
718     LINK_STATS_INC(link.lenerr);
719     goto drop;
720   }
721 
722   PPPDEBUG(LOG_DEBUG, ("pppoe_data_input: %c%c%"U16_F": pkthdr.len=%d, pppoe.len=%d\n",
723         sc->sc_ethif->name[0], sc->sc_ethif->name[1], sc->sc_ethif->num,
724         pb->len, plen));
725 
726   if (pb->tot_len < plen) {
727     goto drop;
728   }
729 
730   /* Dispatch the packet thereby consuming it. */
731   ppp_input(sc->pcb, pb);
732   return;
733 
734 drop:
735   pbuf_free(pb);
736 }
737 
738 static err_t
pppoe_output(struct pppoe_softc * sc,struct pbuf * pb)739 pppoe_output(struct pppoe_softc *sc, struct pbuf *pb)
740 {
741   struct eth_hdr *ethhdr;
742   u16_t etype;
743   err_t res;
744 
745   /* make room for Ethernet header - should not fail */
746   if (pbuf_add_header(pb, sizeof(struct eth_hdr)) != 0) {
747     /* bail out */
748     PPPDEBUG(LOG_ERR, ("pppoe: %c%c%"U16_F": pppoe_output: could not allocate room for Ethernet header\n", sc->sc_ethif->name[0], sc->sc_ethif->name[1], sc->sc_ethif->num));
749     LINK_STATS_INC(link.lenerr);
750     pbuf_free(pb);
751     return ERR_BUF;
752   }
753   ethhdr = (struct eth_hdr *)pb->payload;
754   etype = sc->sc_state == PPPOE_STATE_SESSION ? ETHTYPE_PPPOE : ETHTYPE_PPPOEDISC;
755   ethhdr->type = lwip_htons(etype);
756   MEMCPY(&ethhdr->dest.addr, &sc->sc_dest.addr, sizeof(ethhdr->dest.addr));
757   MEMCPY(&ethhdr->src.addr, &sc->sc_ethif->hwaddr, sizeof(ethhdr->src.addr));
758 
759   PPPDEBUG(LOG_DEBUG, ("pppoe: %c%c%"U16_F" (%x) state=%d, session=0x%x output -> %02"X16_F":%02"X16_F":%02"X16_F":%02"X16_F":%02"X16_F":%02"X16_F", len=%d\n",
760       sc->sc_ethif->name[0], sc->sc_ethif->name[1], sc->sc_ethif->num, etype,
761       sc->sc_state, sc->sc_session,
762       sc->sc_dest.addr[0], sc->sc_dest.addr[1], sc->sc_dest.addr[2], sc->sc_dest.addr[3], sc->sc_dest.addr[4], sc->sc_dest.addr[5],
763       pb->tot_len));
764 
765   res = sc->sc_ethif->linkoutput(sc->sc_ethif, pb);
766 
767   pbuf_free(pb);
768 
769   return res;
770 }
771 
772 static err_t
pppoe_send_padi(struct pppoe_softc * sc)773 pppoe_send_padi(struct pppoe_softc *sc)
774 {
775   struct pbuf *pb;
776   u8_t *p;
777   size_t len;
778 #if PPPOE_SCNAME_SUPPORT
779   size_t l1 = 0, l2 = 0; /* XXX: gcc */
780 #endif /* PPPOE_SCNAME_SUPPORT */
781 
782   /* calculate length of frame (excluding ethernet header + pppoe header) */
783   len = 2 + 2 + 2 + 2 + sizeof sc;  /* service name tag is required, host unique is send too */
784 #if PPPOE_SCNAME_SUPPORT
785   if (sc->sc_service_name != NULL) {
786     l1 = strlen(sc->sc_service_name);
787     len += l1;
788   }
789   if (sc->sc_concentrator_name != NULL) {
790     l2 = strlen(sc->sc_concentrator_name);
791     len += 2 + 2 + l2;
792   }
793 #endif /* PPPOE_SCNAME_SUPPORT */
794   LWIP_ASSERT("sizeof(struct eth_hdr) + PPPOE_HEADERLEN + len <= 0xffff",
795     sizeof(struct eth_hdr) + PPPOE_HEADERLEN + len <= 0xffff);
796 
797   /* allocate a buffer */
798   pb = pbuf_alloc(PBUF_LINK, (u16_t)(PPPOE_HEADERLEN + len), PBUF_RAM);
799   if (!pb) {
800     return ERR_MEM;
801   }
802   LWIP_ASSERT("pb->tot_len == pb->len", pb->tot_len == pb->len);
803 
804   p = (u8_t*)pb->payload;
805   /* fill in pkt */
806   PPPOE_ADD_HEADER(p, PPPOE_CODE_PADI, 0, (u16_t)len);
807   PPPOE_ADD_16(p, PPPOE_TAG_SNAME);
808 #if PPPOE_SCNAME_SUPPORT
809   if (sc->sc_service_name != NULL) {
810     PPPOE_ADD_16(p, l1);
811     MEMCPY(p, sc->sc_service_name, l1);
812     p += l1;
813   } else
814 #endif /* PPPOE_SCNAME_SUPPORT */
815   {
816     PPPOE_ADD_16(p, 0);
817   }
818 #if PPPOE_SCNAME_SUPPORT
819   if (sc->sc_concentrator_name != NULL) {
820     PPPOE_ADD_16(p, PPPOE_TAG_ACNAME);
821     PPPOE_ADD_16(p, l2);
822     MEMCPY(p, sc->sc_concentrator_name, l2);
823     p += l2;
824   }
825 #endif /* PPPOE_SCNAME_SUPPORT */
826   PPPOE_ADD_16(p, PPPOE_TAG_HUNIQUE);
827   PPPOE_ADD_16(p, sizeof(sc));
828   MEMCPY(p, &sc, sizeof sc);
829 
830   /* send pkt */
831   return pppoe_output(sc, pb);
832 }
833 
834 static void
pppoe_timeout(void * arg)835 pppoe_timeout(void *arg)
836 {
837   u32_t retry_wait;
838   int err;
839   struct pppoe_softc *sc = (struct pppoe_softc*)arg;
840 
841   PPPDEBUG(LOG_DEBUG, ("pppoe: %c%c%"U16_F": timeout\n", sc->sc_ethif->name[0], sc->sc_ethif->name[1], sc->sc_ethif->num));
842 
843   switch (sc->sc_state) {
844     case PPPOE_STATE_PADI_SENT:
845       /*
846        * We have two basic ways of retrying:
847        *  - Quick retry mode: try a few times in short sequence
848        *  - Slow retry mode: we already had a connection successfully
849        *    established and will try infinitely (without user
850        *    intervention)
851        * We only enter slow retry mode if IFF_LINK1 (aka autodial)
852        * is not set.
853        */
854       if (sc->sc_padi_retried < 0xff) {
855         sc->sc_padi_retried++;
856       }
857       if (!sc->pcb->settings.persist && sc->sc_padi_retried >= PPPOE_DISC_MAXPADI) {
858 #if 0
859         if ((sc->sc_sppp.pp_if.if_flags & IFF_LINK1) == 0) {
860           /* slow retry mode */
861           retry_wait = PPPOE_SLOW_RETRY;
862         } else
863 #endif
864         {
865           pppoe_abort_connect(sc);
866           return;
867         }
868       }
869       /* initialize for quick retry mode */
870       retry_wait = LWIP_MIN(PPPOE_DISC_TIMEOUT * sc->sc_padi_retried, PPPOE_SLOW_RETRY);
871       if ((err = pppoe_send_padi(sc)) != 0) {
872         PPPDEBUG(LOG_DEBUG, ("pppoe: %c%c%"U16_F": failed to transmit PADI, error=%d\n", sc->sc_ethif->name[0], sc->sc_ethif->name[1], sc->sc_ethif->num, err));
873         LWIP_UNUSED_ARG(err); /* if PPPDEBUG is disabled */
874       }
875       sys_timeout(retry_wait, pppoe_timeout, sc);
876       break;
877 
878     case PPPOE_STATE_PADR_SENT:
879       sc->sc_padr_retried++;
880       if (sc->sc_padr_retried >= PPPOE_DISC_MAXPADR) {
881         MEMCPY(&sc->sc_dest, ethbroadcast.addr, sizeof(sc->sc_dest));
882         sc->sc_state = PPPOE_STATE_PADI_SENT;
883         sc->sc_padr_retried = 0;
884         if ((err = pppoe_send_padi(sc)) != 0) {
885           PPPDEBUG(LOG_DEBUG, ("pppoe: %c%c%"U16_F": failed to send PADI, error=%d\n", sc->sc_ethif->name[0], sc->sc_ethif->name[1], sc->sc_ethif->num, err));
886           LWIP_UNUSED_ARG(err); /* if PPPDEBUG is disabled */
887         }
888         sys_timeout(PPPOE_DISC_TIMEOUT * (1 + sc->sc_padi_retried), pppoe_timeout, sc);
889         return;
890       }
891       if ((err = pppoe_send_padr(sc)) != 0) {
892         PPPDEBUG(LOG_DEBUG, ("pppoe: %c%c%"U16_F": failed to send PADR, error=%d\n", sc->sc_ethif->name[0], sc->sc_ethif->name[1], sc->sc_ethif->num, err));
893         LWIP_UNUSED_ARG(err); /* if PPPDEBUG is disabled */
894       }
895       sys_timeout(PPPOE_DISC_TIMEOUT * (1 + sc->sc_padr_retried), pppoe_timeout, sc);
896       break;
897     default:
898       return;  /* all done, work in peace */
899   }
900 }
901 
902 /* Start a connection (i.e. initiate discovery phase) */
903 static void
pppoe_connect(ppp_pcb * ppp,void * ctx)904 pppoe_connect(ppp_pcb *ppp, void *ctx)
905 {
906   err_t err;
907   struct pppoe_softc *sc = (struct pppoe_softc *)ctx;
908   lcp_options *lcp_wo;
909   lcp_options *lcp_ao;
910 #if PPP_IPV4_SUPPORT && VJ_SUPPORT
911   ipcp_options *ipcp_wo;
912   ipcp_options *ipcp_ao;
913 #endif /* PPP_IPV4_SUPPORT && VJ_SUPPORT */
914 
915   sc->sc_session = 0;
916   sc->sc_ac_cookie_len = 0;
917   sc->sc_padi_retried = 0;
918   sc->sc_padr_retried = 0;
919   /* changed to real address later */
920   MEMCPY(&sc->sc_dest, ethbroadcast.addr, sizeof(sc->sc_dest));
921 #ifdef PPPOE_SERVER
922   /* wait PADI if IFF_PASSIVE */
923   if ((sc->sc_sppp.pp_if.if_flags & IFF_PASSIVE)) {
924     return 0;
925   }
926 #endif
927 
928   lcp_wo = &ppp->lcp_wantoptions;
929   lcp_wo->mru = sc->sc_ethif->mtu-PPPOE_HEADERLEN-2; /* two byte PPP protocol discriminator, then IP data */
930   lcp_wo->neg_asyncmap = 0;
931   lcp_wo->neg_pcompression = 0;
932   lcp_wo->neg_accompression = 0;
933   lcp_wo->passive = 0;
934   lcp_wo->silent = 0;
935 
936   lcp_ao = &ppp->lcp_allowoptions;
937   lcp_ao->mru = sc->sc_ethif->mtu-PPPOE_HEADERLEN-2; /* two byte PPP protocol discriminator, then IP data */
938   lcp_ao->neg_asyncmap = 0;
939   lcp_ao->neg_pcompression = 0;
940   lcp_ao->neg_accompression = 0;
941 
942 #if PPP_IPV4_SUPPORT && VJ_SUPPORT
943   ipcp_wo = &ppp->ipcp_wantoptions;
944   ipcp_wo->neg_vj = 0;
945   ipcp_wo->old_vj = 0;
946 
947   ipcp_ao = &ppp->ipcp_allowoptions;
948   ipcp_ao->neg_vj = 0;
949   ipcp_ao->old_vj = 0;
950 #endif /* PPP_IPV4_SUPPORT && VJ_SUPPORT */
951 
952   /* save state, in case we fail to send PADI */
953   sc->sc_state = PPPOE_STATE_PADI_SENT;
954   if ((err = pppoe_send_padi(sc)) != 0) {
955     PPPDEBUG(LOG_DEBUG, ("pppoe: %c%c%"U16_F": failed to send PADI, error=%d\n", sc->sc_ethif->name[0], sc->sc_ethif->name[1], sc->sc_ethif->num, err));
956   }
957   sys_timeout(PPPOE_DISC_TIMEOUT, pppoe_timeout, sc);
958 }
959 
960 /* disconnect */
961 static void
pppoe_disconnect(ppp_pcb * ppp,void * ctx)962 pppoe_disconnect(ppp_pcb *ppp, void *ctx)
963 {
964   struct pppoe_softc *sc = (struct pppoe_softc *)ctx;
965 
966   PPPDEBUG(LOG_DEBUG, ("pppoe: %c%c%"U16_F": disconnecting\n", sc->sc_ethif->name[0], sc->sc_ethif->name[1], sc->sc_ethif->num));
967   if (sc->sc_state == PPPOE_STATE_SESSION) {
968     pppoe_send_padt(sc->sc_ethif, sc->sc_session, (const u8_t *)&sc->sc_dest);
969   }
970 
971   /* stop any timer, disconnect can be called while initiating is in progress */
972   sys_untimeout(pppoe_timeout, sc);
973   sc->sc_state = PPPOE_STATE_INITIAL;
974 #ifdef PPPOE_SERVER
975   if (sc->sc_hunique) {
976     mem_free(sc->sc_hunique);
977     sc->sc_hunique = NULL; /* probably not necessary, if state is initial we shouldn't have to access hunique anyway  */
978   }
979   sc->sc_hunique_len = 0; /* probably not necessary, if state is initial we shouldn't have to access hunique anyway  */
980 #endif
981   ppp_link_end(ppp); /* notify upper layers */
982   return;
983 }
984 
985 /* Connection attempt aborted */
986 static void
pppoe_abort_connect(struct pppoe_softc * sc)987 pppoe_abort_connect(struct pppoe_softc *sc)
988 {
989   PPPDEBUG(LOG_DEBUG, ("%c%c%"U16_F": could not establish connection\n", sc->sc_ethif->name[0], sc->sc_ethif->name[1], sc->sc_ethif->num));
990   sc->sc_state = PPPOE_STATE_INITIAL;
991   ppp_link_failed(sc->pcb); /* notify upper layers */
992 }
993 
994 /* Send a PADR packet */
995 static err_t
pppoe_send_padr(struct pppoe_softc * sc)996 pppoe_send_padr(struct pppoe_softc *sc)
997 {
998   struct pbuf *pb;
999   u8_t *p;
1000   size_t len;
1001 #if PPPOE_SCNAME_SUPPORT
1002   size_t l1 = 0; /* XXX: gcc */
1003 #endif /* PPPOE_SCNAME_SUPPORT */
1004 
1005   len = 2 + 2 + 2 + 2 + sizeof(sc);    /* service name, host unique */
1006 #if PPPOE_SCNAME_SUPPORT
1007   if (sc->sc_service_name != NULL) {    /* service name tag maybe empty */
1008     l1 = strlen(sc->sc_service_name);
1009     len += l1;
1010   }
1011 #endif /* PPPOE_SCNAME_SUPPORT */
1012   if (sc->sc_ac_cookie_len > 0) {
1013     len += 2 + 2 + sc->sc_ac_cookie_len;  /* AC cookie */
1014   }
1015   LWIP_ASSERT("sizeof(struct eth_hdr) + PPPOE_HEADERLEN + len <= 0xffff",
1016     sizeof(struct eth_hdr) + PPPOE_HEADERLEN + len <= 0xffff);
1017   pb = pbuf_alloc(PBUF_LINK, (u16_t)(PPPOE_HEADERLEN + len), PBUF_RAM);
1018   if (!pb) {
1019     return ERR_MEM;
1020   }
1021   LWIP_ASSERT("pb->tot_len == pb->len", pb->tot_len == pb->len);
1022   p = (u8_t*)pb->payload;
1023   PPPOE_ADD_HEADER(p, PPPOE_CODE_PADR, 0, len);
1024   PPPOE_ADD_16(p, PPPOE_TAG_SNAME);
1025 #if PPPOE_SCNAME_SUPPORT
1026   if (sc->sc_service_name != NULL) {
1027     PPPOE_ADD_16(p, l1);
1028     MEMCPY(p, sc->sc_service_name, l1);
1029     p += l1;
1030   } else
1031 #endif /* PPPOE_SCNAME_SUPPORT */
1032   {
1033     PPPOE_ADD_16(p, 0);
1034   }
1035   if (sc->sc_ac_cookie_len > 0) {
1036     PPPOE_ADD_16(p, PPPOE_TAG_ACCOOKIE);
1037     PPPOE_ADD_16(p, sc->sc_ac_cookie_len);
1038     MEMCPY(p, sc->sc_ac_cookie, sc->sc_ac_cookie_len);
1039     p += sc->sc_ac_cookie_len;
1040   }
1041   PPPOE_ADD_16(p, PPPOE_TAG_HUNIQUE);
1042   PPPOE_ADD_16(p, sizeof(sc));
1043   MEMCPY(p, &sc, sizeof sc);
1044 
1045   return pppoe_output(sc, pb);
1046 }
1047 
1048 /* send a PADT packet */
1049 static err_t
pppoe_send_padt(struct netif * outgoing_if,u_int session,const u8_t * dest)1050 pppoe_send_padt(struct netif *outgoing_if, u_int session, const u8_t *dest)
1051 {
1052   struct pbuf *pb;
1053   struct eth_hdr *ethhdr;
1054   err_t res;
1055   u8_t *p;
1056 
1057   pb = pbuf_alloc(PBUF_LINK, (u16_t)(PPPOE_HEADERLEN), PBUF_RAM);
1058   if (!pb) {
1059     return ERR_MEM;
1060   }
1061   LWIP_ASSERT("pb->tot_len == pb->len", pb->tot_len == pb->len);
1062 
1063   if (pbuf_add_header(pb, sizeof(struct eth_hdr))) {
1064     PPPDEBUG(LOG_ERR, ("pppoe: pppoe_send_padt: could not allocate room for PPPoE header\n"));
1065     LINK_STATS_INC(link.lenerr);
1066     pbuf_free(pb);
1067     return ERR_BUF;
1068   }
1069   ethhdr = (struct eth_hdr *)pb->payload;
1070   ethhdr->type = PP_HTONS(ETHTYPE_PPPOEDISC);
1071   MEMCPY(&ethhdr->dest.addr, dest, sizeof(ethhdr->dest.addr));
1072   MEMCPY(&ethhdr->src.addr, &outgoing_if->hwaddr, sizeof(ethhdr->src.addr));
1073 
1074   p = (u8_t*)(ethhdr + 1);
1075   PPPOE_ADD_HEADER(p, PPPOE_CODE_PADT, session, 0);
1076 
1077   res = outgoing_if->linkoutput(outgoing_if, pb);
1078 
1079   pbuf_free(pb);
1080 
1081   return res;
1082 }
1083 
1084 #ifdef PPPOE_SERVER
1085 static err_t
pppoe_send_pado(struct pppoe_softc * sc)1086 pppoe_send_pado(struct pppoe_softc *sc)
1087 {
1088   struct pbuf *pb;
1089   u8_t *p;
1090   size_t len;
1091 
1092   /* calc length */
1093   len = 0;
1094   /* include ac_cookie */
1095   len += 2 + 2 + sizeof(sc);
1096   /* include hunique */
1097   len += 2 + 2 + sc->sc_hunique_len;
1098   pb = pbuf_alloc(PBUF_LINK, (u16_t)(PPPOE_HEADERLEN + len), PBUF_RAM);
1099   if (!pb) {
1100     return ERR_MEM;
1101   }
1102   LWIP_ASSERT("pb->tot_len == pb->len", pb->tot_len == pb->len);
1103   p = (u8_t*)pb->payload;
1104   PPPOE_ADD_HEADER(p, PPPOE_CODE_PADO, 0, len);
1105   PPPOE_ADD_16(p, PPPOE_TAG_ACCOOKIE);
1106   PPPOE_ADD_16(p, sizeof(sc));
1107   MEMCPY(p, &sc, sizeof(sc));
1108   p += sizeof(sc);
1109   PPPOE_ADD_16(p, PPPOE_TAG_HUNIQUE);
1110   PPPOE_ADD_16(p, sc->sc_hunique_len);
1111   MEMCPY(p, sc->sc_hunique, sc->sc_hunique_len);
1112   return pppoe_output(sc, pb);
1113 }
1114 
1115 static err_t
pppoe_send_pads(struct pppoe_softc * sc)1116 pppoe_send_pads(struct pppoe_softc *sc)
1117 {
1118   struct pbuf *pb;
1119   u8_t *p;
1120   size_t len, l1 = 0;  /* XXX: gcc */
1121 
1122   sc->sc_session = mono_time.tv_sec % 0xff + 1;
1123   /* calc length */
1124   len = 0;
1125   /* include hunique */
1126   len += 2 + 2 + 2 + 2 + sc->sc_hunique_len;  /* service name, host unique*/
1127   if (sc->sc_service_name != NULL) {    /* service name tag maybe empty */
1128     l1 = strlen(sc->sc_service_name);
1129     len += l1;
1130   }
1131   pb = pbuf_alloc(PBUF_LINK, (u16_t)(PPPOE_HEADERLEN + len), PBUF_RAM);
1132   if (!pb) {
1133     return ERR_MEM;
1134   }
1135   LWIP_ASSERT("pb->tot_len == pb->len", pb->tot_len == pb->len);
1136   p = (u8_t*)pb->payload;
1137   PPPOE_ADD_HEADER(p, PPPOE_CODE_PADS, sc->sc_session, len);
1138   PPPOE_ADD_16(p, PPPOE_TAG_SNAME);
1139   if (sc->sc_service_name != NULL) {
1140     PPPOE_ADD_16(p, l1);
1141     MEMCPY(p, sc->sc_service_name, l1);
1142     p += l1;
1143   } else {
1144     PPPOE_ADD_16(p, 0);
1145   }
1146   PPPOE_ADD_16(p, PPPOE_TAG_HUNIQUE);
1147   PPPOE_ADD_16(p, sc->sc_hunique_len);
1148   MEMCPY(p, sc->sc_hunique, sc->sc_hunique_len);
1149   return pppoe_output(sc, pb);
1150 }
1151 #endif
1152 
1153 static err_t
pppoe_xmit(struct pppoe_softc * sc,struct pbuf * pb)1154 pppoe_xmit(struct pppoe_softc *sc, struct pbuf *pb)
1155 {
1156   u8_t *p;
1157   size_t len;
1158 
1159   len = pb->tot_len;
1160 
1161   /* make room for PPPoE header - should not fail */
1162   if (pbuf_add_header(pb, PPPOE_HEADERLEN) != 0) {
1163     /* bail out */
1164     PPPDEBUG(LOG_ERR, ("pppoe: %c%c%"U16_F": pppoe_xmit: could not allocate room for PPPoE header\n", sc->sc_ethif->name[0], sc->sc_ethif->name[1], sc->sc_ethif->num));
1165     LINK_STATS_INC(link.lenerr);
1166     pbuf_free(pb);
1167     return ERR_BUF;
1168   }
1169 
1170   p = (u8_t*)pb->payload;
1171   PPPOE_ADD_HEADER(p, 0, sc->sc_session, len);
1172 
1173   return pppoe_output(sc, pb);
1174 }
1175 
1176 #if 0 /*def PFIL_HOOKS*/
1177 static int
1178 pppoe_ifattach_hook(void *arg, struct pbuf **mp, struct netif *ifp, int dir)
1179 {
1180   struct pppoe_softc *sc;
1181   int s;
1182 
1183   if (mp != (struct pbuf **)PFIL_IFNET_DETACH) {
1184     return 0;
1185   }
1186 
1187   LIST_FOREACH(sc, &pppoe_softc_list, sc_list) {
1188     if (sc->sc_ethif != ifp) {
1189       continue;
1190     }
1191     if (sc->sc_sppp.pp_if.if_flags & IFF_UP) {
1192       sc->sc_sppp.pp_if.if_flags &= ~(IFF_UP|IFF_RUNNING);
1193       PPPDEBUG(LOG_DEBUG, ("%c%c%"U16_F": ethernet interface detached, going down\n",
1194           sc->sc_ethif->name[0], sc->sc_ethif->name[1], sc->sc_ethif->num));
1195     }
1196     sc->sc_ethif = NULL;
1197     pppoe_clear_softc(sc, "ethernet interface detached");
1198   }
1199 
1200   return 0;
1201 }
1202 #endif
1203 
1204 #if 0 /* UNUSED */
1205 static void
1206 pppoe_clear_softc(struct pppoe_softc *sc, const char *message)
1207 {
1208   LWIP_UNUSED_ARG(message);
1209 
1210   /* stop timer */
1211   sys_untimeout(pppoe_timeout, sc);
1212   PPPDEBUG(LOG_DEBUG, ("pppoe: %c%c%"U16_F": session 0x%x terminated, %s\n", sc->sc_ethif->name[0], sc->sc_ethif->name[1], sc->sc_ethif->num, sc->sc_session, message));
1213   sc->sc_state = PPPOE_STATE_INITIAL;
1214   ppp_link_end(sc->pcb);  /* notify upper layers - /!\ dangerous /!\ - see pppoe_disc_input() */
1215 }
1216 #endif /* UNUSED */
1217 #endif /* PPP_SUPPORT && PPPOE_SUPPORT */
1218