xref: /openbsd/sys/net/if_pppoe.c (revision 333d623a)
1 /* $OpenBSD: if_pppoe.c,v 1.73 2020/09/13 11:00:40 kn Exp $ */
2 /* $NetBSD: if_pppoe.c,v 1.51 2003/11/28 08:56:48 keihan Exp $ */
3 
4 /*
5  * Copyright (c) 2002 The NetBSD Foundation, Inc.
6  * All rights reserved.
7  *
8  * This code is derived from software contributed to The NetBSD Foundation
9  * by Martin Husemann <martin@NetBSD.org>.
10  *
11  * Redistribution and use in source and binary forms, with or without
12  * modification, are permitted provided that the following conditions
13  * are met:
14  * 1. Redistributions of source code must retain the above copyright
15  *    notice, this list of conditions and the following disclaimer.
16  * 2. Redistributions in binary form must reproduce the above copyright
17  *    notice, this list of conditions and the following disclaimer in the
18  *    documentation and/or other materials provided with the distribution.
19  *
20  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
21  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
22  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
23  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
24  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
25  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
26  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
27  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
28  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
29  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
30  * POSSIBILITY OF SUCH DAMAGE.
31  */
32 
33 #include "pppoe.h"
34 #include "bpfilter.h"
35 
36 #include <sys/param.h>
37 #include <sys/systm.h>
38 #include <sys/kernel.h>
39 #include <sys/timeout.h>
40 #include <sys/malloc.h>
41 #include <sys/mbuf.h>
42 #include <sys/socket.h>
43 #include <sys/syslog.h>
44 #include <sys/ioctl.h>
45 #include <net/if.h>
46 #include <net/if_var.h>
47 #include <net/if_types.h>
48 #include <net/if_sppp.h>
49 #include <net/if_pppoe.h>
50 #include <net/netisr.h>
51 #include <netinet/in.h>
52 #include <netinet/if_ether.h>
53 
54 #if NBPFILTER > 0
55 #include <net/bpf.h>
56 #endif
57 
58 #undef PPPOE_DEBUG	/* XXX - remove this or make it an option */
59 
60 #define PPPOEDEBUG(a)	((sc->sc_sppp.pp_if.if_flags & IFF_DEBUG) ? printf a : 0)
61 
62 struct pppoehdr {
63 	u_int8_t vertype;
64 	u_int8_t code;
65 	u_int16_t session;
66 	u_int16_t plen;
67 } __packed;
68 
69 struct pppoetag {
70 	u_int16_t tag;
71 	u_int16_t len;
72 } __packed;
73 
74 #define	PPPOE_HEADERLEN		sizeof(struct pppoehdr)
75 #define	PPPOE_OVERHEAD		(PPPOE_HEADERLEN + 2)
76 #define	PPPOE_VERTYPE		0x11		/* VER=1, TYPE = 1 */
77 
78 #define	PPPOE_TAG_EOL		0x0000		/* end of list */
79 #define	PPPOE_TAG_SNAME		0x0101		/* service name */
80 #define	PPPOE_TAG_ACNAME	0x0102		/* access concentrator name */
81 #define	PPPOE_TAG_HUNIQUE	0x0103		/* host unique */
82 #define	PPPOE_TAG_ACCOOKIE	0x0104		/* AC cookie */
83 #define	PPPOE_TAG_VENDOR	0x0105		/* vendor specific */
84 #define	PPPOE_TAG_RELAYSID	0x0110		/* relay session id */
85 #define	PPPOE_TAG_MAX_PAYLOAD	0x0120		/* RFC 4638 max payload */
86 #define	PPPOE_TAG_SNAME_ERR	0x0201		/* service name error */
87 #define	PPPOE_TAG_ACSYS_ERR	0x0202		/* AC system error */
88 #define	PPPOE_TAG_GENERIC_ERR	0x0203		/* generic error */
89 
90 #define	PPPOE_CODE_PADI		0x09		/* Active Discovery Initiation */
91 #define	PPPOE_CODE_PADO		0x07		/* Active Discovery Offer */
92 #define	PPPOE_CODE_PADR		0x19		/* Active Discovery Request */
93 #define	PPPOE_CODE_PADS		0x65		/* Active Discovery Session confirmation */
94 #define	PPPOE_CODE_PADT		0xA7		/* Active Discovery Terminate */
95 
96 /* two byte PPP protocol discriminator, then IP data */
97 #define	PPPOE_MTU	(ETHERMTU - PPPOE_OVERHEAD)
98 #define	PPPOE_MAXMTU	PP_MAX_MRU
99 
100 /* Add a 16 bit unsigned value to a buffer pointed to by PTR */
101 #define	PPPOE_ADD_16(PTR, VAL)			\
102 		*(PTR)++ = (VAL) / 256;		\
103 		*(PTR)++ = (VAL) % 256
104 
105 /* Add a complete PPPoE header to the buffer pointed to by PTR */
106 #define	PPPOE_ADD_HEADER(PTR, CODE, SESS, LEN)	\
107 		*(PTR)++ = PPPOE_VERTYPE;	\
108 		*(PTR)++ = (CODE);		\
109 		PPPOE_ADD_16(PTR, SESS);	\
110 		PPPOE_ADD_16(PTR, LEN)
111 
112 #define	PPPOE_DISC_TIMEOUT	5	/* base for quick timeout calculation (seconds) */
113 #define	PPPOE_SLOW_RETRY	60	/* persistent retry interval (seconds) */
114 #define	PPPOE_DISC_MAXPADI	4	/* retry PADI four times (quickly) */
115 #define	PPPOE_DISC_MAXPADR	2	/* retry PADR twice */
116 
117 /*
118  * Locks used to protect struct members and global data
119  *       I       immutable after creation
120  *       N       net lock
121  */
122 
123 struct pppoe_softc {
124 	struct sppp sc_sppp;		/* contains a struct ifnet as first element */
125 	LIST_ENTRY(pppoe_softc) sc_list;/* [N] */
126 	unsigned int sc_eth_ifidx;	/* [N] */
127 
128 	int sc_state;			/* [N] discovery phase or session connected */
129 	struct ether_addr sc_dest;	/* [N] hardware address of concentrator */
130 	u_int16_t sc_session;		/* [N] PPPoE session id */
131 
132 	char *sc_service_name;		/* [N] if != NULL: requested name of service */
133 	char *sc_concentrator_name;	/* [N] if != NULL: requested concentrator id */
134 	u_int8_t *sc_ac_cookie;		/* [N] content of AC cookie we must echo back */
135 	size_t sc_ac_cookie_len;	/* [N] length of cookie data */
136 	u_int8_t *sc_relay_sid;		/* [N] content of relay SID we must echo back */
137 	size_t sc_relay_sid_len;	/* [N] length of relay SID data */
138 	u_int32_t sc_unique;		/* [I] our unique id */
139 	struct timeout sc_timeout;	/* [N] timeout while not in session state */
140 	int sc_padi_retried;		/* [N] number of PADI retries already done */
141 	int sc_padr_retried;		/* [N] number of PADR retries already done */
142 
143 	struct timeval sc_session_time;	/* [N] time the session was established */
144 };
145 
146 /* incoming traffic will be queued here */
147 struct niqueue pppoediscinq = NIQUEUE_INITIALIZER(IFQ_MAXLEN, NETISR_PPPOE);
148 struct niqueue pppoeinq = NIQUEUE_INITIALIZER(IFQ_MAXLEN, NETISR_PPPOE);
149 
150 /* input routines */
151 static void pppoe_disc_input(struct mbuf *);
152 static void pppoe_dispatch_disc_pkt(struct mbuf *, int);
153 static void pppoe_data_input(struct mbuf *);
154 
155 /* management routines */
156 void pppoeattach(int);
157 static int  pppoe_connect(struct pppoe_softc *);
158 static int  pppoe_disconnect(struct pppoe_softc *);
159 static void pppoe_abort_connect(struct pppoe_softc *);
160 static int  pppoe_ioctl(struct ifnet *, unsigned long, caddr_t);
161 static void pppoe_tls(struct sppp *);
162 static void pppoe_tlf(struct sppp *);
163 static void pppoe_start(struct ifnet *);
164 
165 /* internal timeout handling */
166 static void pppoe_timeout(void *);
167 
168 /* sending actual protocol control packets */
169 static int pppoe_send_padi(struct pppoe_softc *);
170 static int pppoe_send_padr(struct pppoe_softc *);
171 static int pppoe_send_padt(unsigned int, u_int, const u_int8_t *, u_int8_t);
172 
173 /* raw output */
174 static int pppoe_output(struct pppoe_softc *, struct mbuf *);
175 
176 /* internal helper functions */
177 static struct pppoe_softc *pppoe_find_softc_by_session(u_int, u_int);
178 static struct pppoe_softc *pppoe_find_softc_by_hunique(u_int8_t *, size_t, u_int);
179 static struct mbuf	  *pppoe_get_mbuf(size_t len);
180 
181 LIST_HEAD(pppoe_softc_head, pppoe_softc) pppoe_softc_list;
182 
183 /* interface cloning */
184 int pppoe_clone_create(struct if_clone *, int);
185 int pppoe_clone_destroy(struct ifnet *);
186 
187 struct if_clone pppoe_cloner =
188     IF_CLONE_INITIALIZER("pppoe", pppoe_clone_create, pppoe_clone_destroy);
189 
190 
191 void
192 pppoeattach(int count)
193 {
194 	LIST_INIT(&pppoe_softc_list);
195 	if_clone_attach(&pppoe_cloner);
196 }
197 
198 /* Create a new interface. */
199 int
200 pppoe_clone_create(struct if_clone *ifc, int unit)
201 {
202 	struct pppoe_softc *sc, *tmpsc;
203 	u_int32_t unique;
204 
205 	sc = malloc(sizeof(*sc), M_DEVBUF, M_WAITOK|M_ZERO);
206 	snprintf(sc->sc_sppp.pp_if.if_xname,
207 		 sizeof(sc->sc_sppp.pp_if.if_xname),
208 		 "pppoe%d", unit);
209 	sc->sc_sppp.pp_if.if_softc = sc;
210 	sc->sc_sppp.pp_if.if_mtu = PPPOE_MTU;
211 	sc->sc_sppp.pp_if.if_flags = IFF_SIMPLEX | IFF_POINTOPOINT | IFF_MULTICAST;
212 	sc->sc_sppp.pp_if.if_type = IFT_PPP;
213 	sc->sc_sppp.pp_if.if_hdrlen = sizeof(struct ether_header) + PPPOE_HEADERLEN;
214 	sc->sc_sppp.pp_flags |= PP_KEEPALIVE;		/* use LCP keepalive */
215 	sc->sc_sppp.pp_framebytes = PPPOE_HEADERLEN;	/* framing added to ppp packets */
216 	sc->sc_sppp.pp_if.if_ioctl = pppoe_ioctl;
217 	sc->sc_sppp.pp_if.if_start = pppoe_start;
218 	sc->sc_sppp.pp_if.if_rtrequest = p2p_rtrequest;
219 	sc->sc_sppp.pp_if.if_xflags = IFXF_CLONED;
220 	sc->sc_sppp.pp_tls = pppoe_tls;
221 	sc->sc_sppp.pp_tlf = pppoe_tlf;
222 
223 	/* changed to real address later */
224 	memcpy(&sc->sc_dest, etherbroadcastaddr, sizeof(sc->sc_dest));
225 
226 	/* init timer for interface watchdog */
227 	timeout_set_proc(&sc->sc_timeout, pppoe_timeout, sc);
228 
229 	if_attach(&sc->sc_sppp.pp_if);
230 	if_alloc_sadl(&sc->sc_sppp.pp_if);
231 	sppp_attach(&sc->sc_sppp.pp_if);
232 #if NBPFILTER > 0
233 	bpfattach(&sc->sc_sppp.pp_if.if_bpf, &sc->sc_sppp.pp_if, DLT_PPP_ETHER, 0);
234 #endif
235 
236 	NET_LOCK();
237 retry:
238 	unique = arc4random();
239 	LIST_FOREACH(tmpsc, &pppoe_softc_list, sc_list)
240 		if (tmpsc->sc_unique == unique)
241 			goto retry;
242 	sc->sc_unique = unique;
243 	LIST_INSERT_HEAD(&pppoe_softc_list, sc, sc_list);
244 	NET_UNLOCK();
245 
246 	return (0);
247 }
248 
249 /* Destroy a given interface. */
250 int
251 pppoe_clone_destroy(struct ifnet *ifp)
252 {
253 	struct pppoe_softc *sc = ifp->if_softc;
254 
255 	NET_LOCK();
256 	LIST_REMOVE(sc, sc_list);
257 	NET_UNLOCK();
258 
259 	timeout_del(&sc->sc_timeout);
260 
261 	sppp_detach(&sc->sc_sppp.pp_if);
262 	if_detach(ifp);
263 
264 	if (sc->sc_concentrator_name)
265 		free(sc->sc_concentrator_name, M_DEVBUF,
266 		    strlen(sc->sc_concentrator_name) + 1);
267 	if (sc->sc_service_name)
268 		free(sc->sc_service_name, M_DEVBUF,
269 		    strlen(sc->sc_service_name) + 1);
270 	if (sc->sc_ac_cookie)
271 		free(sc->sc_ac_cookie, M_DEVBUF, sc->sc_ac_cookie_len);
272 	if (sc->sc_relay_sid)
273 		free(sc->sc_relay_sid, M_DEVBUF, sc->sc_relay_sid_len);
274 
275 	free(sc, M_DEVBUF, sizeof(*sc));
276 
277 	return (0);
278 }
279 
280 /*
281  * Find the interface handling the specified session.
282  * Note: O(number of sessions open), this is a client-side only, mean
283  * and lean implementation, so number of open sessions typically should
284  * be 1.
285  */
286 static struct pppoe_softc *
287 pppoe_find_softc_by_session(u_int session, u_int ifidx)
288 {
289 	struct pppoe_softc *sc;
290 
291 	if (session == 0)
292 		return (NULL);
293 
294 	LIST_FOREACH(sc, &pppoe_softc_list, sc_list) {
295 		if (sc->sc_state == PPPOE_STATE_SESSION
296 		    && sc->sc_session == session
297 		    && sc->sc_eth_ifidx == ifidx) {
298 			return (sc);
299 		}
300 	}
301 	return (NULL);
302 }
303 
304 /*
305  * Check host unique token passed and return appropriate softc pointer,
306  * or NULL if token is bogus.
307  */
308 static struct pppoe_softc *
309 pppoe_find_softc_by_hunique(u_int8_t *token, size_t len, u_int ifidx)
310 {
311 	struct pppoe_softc *sc;
312 	u_int32_t hunique;
313 
314 	if (LIST_EMPTY(&pppoe_softc_list))
315 		return (NULL);
316 
317 	if (len != sizeof(hunique))
318 		return (NULL);
319 	memcpy(&hunique, token, len);
320 
321 	LIST_FOREACH(sc, &pppoe_softc_list, sc_list)
322 		if (sc->sc_unique == hunique)
323 			break;
324 
325 	if (sc == NULL) {
326 		printf("pppoe: alien host unique tag, no session found\n");
327 		return (NULL);
328 	}
329 
330 	/* should be safe to access *sc now */
331 	if (sc->sc_state < PPPOE_STATE_PADI_SENT || sc->sc_state >= PPPOE_STATE_SESSION) {
332 		printf("%s: host unique tag found, but it belongs to a connection in state %d\n",
333 			sc->sc_sppp.pp_if.if_xname, sc->sc_state);
334 		return (NULL);
335 	}
336 	if (sc->sc_eth_ifidx != ifidx) {
337 		printf("%s: wrong interface, not accepting host unique\n",
338 			sc->sc_sppp.pp_if.if_xname);
339 		return (NULL);
340 	}
341 	return (sc);
342 }
343 
344 /* Interface interrupt handler routine. */
345 void
346 pppoeintr(void)
347 {
348 	struct mbuf *m;
349 
350 	NET_ASSERT_LOCKED();
351 
352 	while ((m = niq_dequeue(&pppoediscinq)) != NULL)
353 		pppoe_disc_input(m);
354 
355 	while ((m = niq_dequeue(&pppoeinq)) != NULL)
356 		pppoe_data_input(m);
357 }
358 
359 /* Analyze and handle a single received packet while not in session state. */
360 static void pppoe_dispatch_disc_pkt(struct mbuf *m, int off)
361 {
362 	struct pppoe_softc *sc;
363 	struct pppoehdr *ph;
364 	struct pppoetag *pt;
365 	struct mbuf *n;
366 	struct ether_header *eh;
367 	const char *err_msg, *devname;
368 	size_t ac_cookie_len;
369 	size_t relay_sid_len;
370 	int noff, err, errortag;
371 	u_int16_t *max_payload;
372 	u_int16_t tag, len;
373 	u_int16_t session, plen;
374 	u_int8_t *ac_cookie;
375 	u_int8_t *relay_sid;
376 	u_int8_t code;
377 
378 	err_msg = NULL;
379 	devname = "pppoe";
380 	errortag = 0;
381 
382 	if (m->m_len < sizeof(*eh)) {
383 		m = m_pullup(m, sizeof(*eh));
384 		if (m == NULL)
385 			goto done;
386 	}
387 	eh = mtod(m, struct ether_header *);
388 	off += sizeof(*eh);
389 
390 	ac_cookie = NULL;
391 	ac_cookie_len = 0;
392 	relay_sid = NULL;
393 	relay_sid_len = 0;
394 	max_payload = NULL;
395 
396 	session = 0;
397 	if (m->m_pkthdr.len - off <= PPPOE_HEADERLEN) {
398 		printf("pppoe: packet too short: %d\n", m->m_pkthdr.len);
399 		goto done;
400 	}
401 
402 	n = m_pulldown(m, off, sizeof(*ph), &noff);
403 	if (n == NULL) {
404 		printf("pppoe: could not get PPPoE header\n");
405 		m = NULL;
406 		goto done;
407 	}
408 	ph = (struct pppoehdr *)(mtod(n, caddr_t) + noff);
409 	if (ph->vertype != PPPOE_VERTYPE) {
410 		printf("pppoe: unknown version/type packet: 0x%x\n",
411 		    ph->vertype);
412 		goto done;
413 	}
414 
415 	session = ntohs(ph->session);
416 	plen = ntohs(ph->plen);
417 	code = ph->code;
418 	off += sizeof(*ph);
419 	if (plen + off > m->m_pkthdr.len) {
420 		printf("pppoe: packet content does not fit: data available = %d, packet size = %u\n",
421 		    m->m_pkthdr.len - off, plen);
422 		goto done;
423 	}
424 
425 	/* ignore trailing garbage */
426 	m_adj(m, off + plen - m->m_pkthdr.len);
427 
428 	tag = 0;
429 	len = 0;
430 	sc = NULL;
431 	while (off + sizeof(*pt) <= m->m_pkthdr.len) {
432 		n = m_pulldown(m, off, sizeof(*pt), &noff);
433 		if (n == NULL) {
434 			printf("%s: parse error\n", devname);
435 			m = NULL;
436 			goto done;
437 		}
438 		pt = (struct pppoetag *)(mtod(n, caddr_t) + noff);
439 		tag = ntohs(pt->tag);
440 		len = ntohs(pt->len);
441 		off += sizeof(*pt);
442 		if (off + len > m->m_pkthdr.len) {
443 			printf("%s: tag 0x%x len 0x%x is too long\n",
444 			    devname, tag, len);
445 			goto done;
446 		}
447 		switch (tag) {
448 		case PPPOE_TAG_EOL:
449 			goto breakbreak;
450 		case PPPOE_TAG_SNAME:
451 			break;	/* ignored */
452 		case PPPOE_TAG_ACNAME:
453 			break;	/* ignored */
454 		case PPPOE_TAG_HUNIQUE:
455 			if (sc != NULL)
456 				break;
457 			n = m_pulldown(m, off, len, &noff);
458 			if (n == NULL) {
459 				m = NULL;
460 				err_msg = "TAG HUNIQUE ERROR";
461 				break;
462 			}
463 			sc = pppoe_find_softc_by_hunique(mtod(n, caddr_t) + noff,
464 			    len, m->m_pkthdr.ph_ifidx);
465 			if (sc != NULL)
466 				devname = sc->sc_sppp.pp_if.if_xname;
467 			break;
468 		case PPPOE_TAG_ACCOOKIE:
469 			if (ac_cookie == NULL) {
470 				n = m_pulldown(m, off, len,
471 				    &noff);
472 				if (n == NULL) {
473 					err_msg = "TAG ACCOOKIE ERROR";
474 					m = NULL;
475 					break;
476 				}
477 				ac_cookie = mtod(n, caddr_t) + noff;
478 				ac_cookie_len = len;
479 			}
480 			break;
481 		case PPPOE_TAG_RELAYSID:
482 			if (relay_sid == NULL) {
483 				n = m_pulldown(m, off, len,
484 				    &noff);
485 				if (n == NULL) {
486 					err_msg = "TAG RELAYSID ERROR";
487 					m = NULL;
488 					break;
489 				}
490 				relay_sid = mtod(n, caddr_t) + noff;
491 				relay_sid_len = len;
492 			}
493 			break;
494 		case PPPOE_TAG_MAX_PAYLOAD:
495 			if (max_payload == NULL) {
496 				n = m_pulldown(m, off, len,
497 				    &noff);
498 				if (n == NULL || len != 2) {
499 					err_msg = "TAG MAX_PAYLOAD ERROR";
500 					m = NULL;
501 					break;
502 				}
503 				max_payload = (u_int16_t *)(mtod(n, caddr_t) + noff);
504 			}
505 			break;
506 		case PPPOE_TAG_SNAME_ERR:
507 			err_msg = "SERVICE NAME ERROR";
508 			errortag = 1;
509 			break;
510 		case PPPOE_TAG_ACSYS_ERR:
511 			err_msg = "AC SYSTEM ERROR";
512 			errortag = 1;
513 			break;
514 		case PPPOE_TAG_GENERIC_ERR:
515 			err_msg = "GENERIC ERROR";
516 			errortag = 1;
517 			break;
518 		}
519 		if (err_msg) {
520 			log(LOG_INFO, "%s: %s: ", devname, err_msg);
521 			if (errortag && len) {
522 				n = m_pulldown(m, off, len,
523 				    &noff);
524 				if (n == NULL) {
525 					m = NULL;
526 				} else {
527 					u_int8_t *et = mtod(n, caddr_t) + noff;
528 					while (len--)
529 						addlog("%c", *et++);
530 				}
531 			}
532 			addlog("\n");
533 			goto done;
534 		}
535 		off += len;
536 	}
537 breakbreak:
538 	switch (code) {
539 	case PPPOE_CODE_PADI:
540 	case PPPOE_CODE_PADR:
541 		/* ignore, we are no access concentrator */
542 		goto done;
543 	case PPPOE_CODE_PADO:
544 		if (sc == NULL) {
545 			/* be quiet if there is not a single pppoe instance */
546 			if (!LIST_EMPTY(&pppoe_softc_list))
547 				printf("pppoe: received PADO but could not find request for it\n");
548 			goto done;
549 		}
550 		if (sc->sc_state != PPPOE_STATE_PADI_SENT) {
551 			printf("%s: received unexpected PADO\n",
552 			    sc->sc_sppp.pp_if.if_xname);
553 			goto done;
554 		}
555 		if (ac_cookie) {
556 			if (sc->sc_ac_cookie)
557 				free(sc->sc_ac_cookie, M_DEVBUF,
558 				    sc->sc_ac_cookie_len);
559 			sc->sc_ac_cookie = malloc(ac_cookie_len, M_DEVBUF,
560 			    M_DONTWAIT);
561 			if (sc->sc_ac_cookie == NULL)
562 				goto done;
563 			sc->sc_ac_cookie_len = ac_cookie_len;
564 			memcpy(sc->sc_ac_cookie, ac_cookie, ac_cookie_len);
565 		}
566 		if (relay_sid) {
567 			if (sc->sc_relay_sid)
568 				free(sc->sc_relay_sid, M_DEVBUF,
569 				    sc->sc_relay_sid_len);
570 			sc->sc_relay_sid = malloc(relay_sid_len, M_DEVBUF,
571 			    M_DONTWAIT);
572 			if (sc->sc_relay_sid == NULL)
573 				goto done;
574 			sc->sc_relay_sid_len = relay_sid_len;
575 			memcpy(sc->sc_relay_sid, relay_sid, relay_sid_len);
576 		}
577 		if (sc->sc_sppp.pp_if.if_mtu > PPPOE_MTU &&
578 		    (max_payload == NULL ||
579 		     ntohs(*max_payload) != sc->sc_sppp.pp_if.if_mtu)) {
580 			printf("%s: No valid PPP-Max-Payload tag received in PADO\n",
581 			    sc->sc_sppp.pp_if.if_xname);
582 			sc->sc_sppp.pp_if.if_mtu = PPPOE_MTU;
583 		}
584 
585 		memcpy(&sc->sc_dest, eh->ether_shost, sizeof(sc->sc_dest));
586 		sc->sc_padr_retried = 0;
587 		sc->sc_state = PPPOE_STATE_PADR_SENT;
588 		if ((err = pppoe_send_padr(sc)) != 0) {
589 			PPPOEDEBUG(("%s: failed to send PADR, error=%d\n",
590 			    sc->sc_sppp.pp_if.if_xname, err));
591 		}
592 		timeout_add_sec(&sc->sc_timeout,
593 		    PPPOE_DISC_TIMEOUT * (1 + sc->sc_padr_retried));
594 
595 		break;
596 	case PPPOE_CODE_PADS:
597 		if (sc == NULL)
598 			goto done;
599 
600 		sc->sc_session = session;
601 		timeout_del(&sc->sc_timeout);
602 		PPPOEDEBUG(("%s: session 0x%x connected\n",
603 		    sc->sc_sppp.pp_if.if_xname, session));
604 		sc->sc_state = PPPOE_STATE_SESSION;
605 		microtime(&sc->sc_session_time);
606 		sc->sc_sppp.pp_up(&sc->sc_sppp);	/* notify upper layers */
607 
608 		break;
609 	case PPPOE_CODE_PADT:
610 		if (sc == NULL)
611 			goto done;
612 
613 		/* stop timer (we might be about to transmit a PADT ourself) */
614 		timeout_del(&sc->sc_timeout);
615 		PPPOEDEBUG(("%s: session 0x%x terminated, received PADT\n",
616 		    sc->sc_sppp.pp_if.if_xname, session));
617 
618 		/* clean up softc */
619 		sc->sc_state = PPPOE_STATE_INITIAL;
620 		memcpy(&sc->sc_dest, etherbroadcastaddr, sizeof(sc->sc_dest));
621 		if (sc->sc_ac_cookie) {
622 			free(sc->sc_ac_cookie, M_DEVBUF,
623 			    sc->sc_ac_cookie_len);
624 			sc->sc_ac_cookie = NULL;
625 		}
626 		if (sc->sc_relay_sid) {
627 			free(sc->sc_relay_sid, M_DEVBUF, sc->sc_relay_sid_len);
628 			sc->sc_relay_sid = NULL;
629 		}
630 		sc->sc_ac_cookie_len = 0;
631 		sc->sc_relay_sid_len = 0;
632 		sc->sc_session = 0;
633 		sc->sc_session_time.tv_sec = 0;
634 		sc->sc_session_time.tv_usec = 0;
635 		sc->sc_sppp.pp_down(&sc->sc_sppp);	/* signal upper layer */
636 
637 		break;
638 	default:
639 		printf("%s: unknown code (0x%04x) session = 0x%04x\n",
640 		    sc ? sc->sc_sppp.pp_if.if_xname : "pppoe",
641 		    code, session);
642 		break;
643 	}
644 
645 done:
646 	m_freem(m);
647 }
648 
649 /* Input function for discovery packets. */
650 static void
651 pppoe_disc_input(struct mbuf *m)
652 {
653 	/* avoid error messages if there is not a single pppoe instance */
654 	if (!LIST_EMPTY(&pppoe_softc_list)) {
655 		KASSERT(m->m_flags & M_PKTHDR);
656 		pppoe_dispatch_disc_pkt(m, 0);
657 	} else
658 		m_freem(m);
659 }
660 
661 /* Input function for data packets */
662 static void
663 pppoe_data_input(struct mbuf *m)
664 {
665 	struct pppoe_softc *sc;
666 	struct pppoehdr *ph;
667 	u_int16_t session, plen;
668 #ifdef PPPOE_TERM_UNKNOWN_SESSIONS
669 	u_int8_t shost[ETHER_ADDR_LEN];
670 #endif
671 	if (LIST_EMPTY(&pppoe_softc_list))
672 		goto drop;
673 
674 	KASSERT(m->m_flags & M_PKTHDR);
675 
676 #ifdef PPPOE_TERM_UNKNOWN_SESSIONS
677 	memcpy(shost, mtod(m, struct ether_header*)->ether_shost, ETHER_ADDR_LEN);
678 #endif
679 	m_adj(m, sizeof(struct ether_header));
680 	if (m->m_pkthdr.len <= PPPOE_HEADERLEN) {
681 		printf("pppoe (data): dropping too short packet: %d bytes\n",
682 		    m->m_pkthdr.len);
683 		goto drop;
684 	}
685 	if (m->m_len < sizeof(*ph)) {
686 		m = m_pullup(m, sizeof(*ph));
687 		if (m == NULL) {
688 			printf("pppoe (data): could not get PPPoE header\n");
689 			return;
690 		}
691 	}
692 	ph = mtod(m, struct pppoehdr *);
693 	if (ph->vertype != PPPOE_VERTYPE) {
694 		printf("pppoe (data): unknown version/type packet: 0x%x\n",
695 		    ph->vertype);
696 		goto drop;
697 	}
698 	if (ph->code != 0)
699 		goto drop;
700 
701 	session = ntohs(ph->session);
702 	sc = pppoe_find_softc_by_session(session, m->m_pkthdr.ph_ifidx);
703 	if (sc == NULL) {
704 #ifdef PPPOE_TERM_UNKNOWN_SESSIONS
705 		printf("pppoe (data): input for unknown session 0x%x, sending PADT\n",
706 		    session);
707 		pppoe_send_padt(m->m_pkthdr.ph_ifidx, session, shost, 0);
708 #endif
709 		goto drop;
710 	}
711 
712 	plen = ntohs(ph->plen);
713 
714 #if NBPFILTER > 0
715 	if(sc->sc_sppp.pp_if.if_bpf)
716 		bpf_mtap(sc->sc_sppp.pp_if.if_bpf, m, BPF_DIRECTION_IN);
717 #endif
718 
719 	m_adj(m, PPPOE_HEADERLEN);
720 
721 #ifdef PPPOE_DEBUG
722 	{
723 		struct mbuf *p;
724 
725 		printf("%s: pkthdr.len=%d, pppoe.len=%d",
726 			sc->sc_sppp.pp_if.if_xname,
727 			m->m_pkthdr.len, plen);
728 		p = m;
729 		while (p) {
730 			printf(" l=%d", p->m_len);
731 			p = p->m_next;
732 		}
733 		printf("\n");
734 	}
735 #endif
736 
737 	if (m->m_pkthdr.len < plen)
738 		goto drop;
739 
740 	/* fix incoming interface pointer (not the raw ethernet interface anymore) */
741 	m->m_pkthdr.ph_ifidx = sc->sc_sppp.pp_if.if_index;
742 
743 	/* pass packet up and account for it */
744 	sc->sc_sppp.pp_if.if_ipackets++;
745 	sppp_input(&sc->sc_sppp.pp_if, m);
746 	return;
747 
748 drop:
749 	m_freem(m);
750 }
751 
752 static int
753 pppoe_output(struct pppoe_softc *sc, struct mbuf *m)
754 {
755 	struct sockaddr dst;
756 	struct ether_header *eh;
757 	struct ifnet *eth_if;
758 	u_int16_t etype;
759 	int ret;
760 
761 	if ((eth_if = if_get(sc->sc_eth_ifidx)) == NULL) {
762 		m_freem(m);
763 		return (EIO);
764 	}
765 
766 	if ((eth_if->if_flags & (IFF_UP|IFF_RUNNING))
767 	    != (IFF_UP|IFF_RUNNING)) {
768 		if_put(eth_if);
769 		m_freem(m);
770 		return (ENETDOWN);
771 	}
772 
773 	memset(&dst, 0, sizeof dst);
774 	dst.sa_family = AF_UNSPEC;
775 	eh = (struct ether_header*)&dst.sa_data;
776 	etype = sc->sc_state == PPPOE_STATE_SESSION ? ETHERTYPE_PPPOE : ETHERTYPE_PPPOEDISC;
777 	eh->ether_type = htons(etype);
778 	memcpy(&eh->ether_dhost, &sc->sc_dest, sizeof sc->sc_dest);
779 
780 	PPPOEDEBUG(("%s (%x) state=%d, session=0x%x output -> %s, len=%d\n",
781 	    sc->sc_sppp.pp_if.if_xname, etype,
782 	    sc->sc_state, sc->sc_session,
783 	    ether_sprintf((unsigned char *)&sc->sc_dest), m->m_pkthdr.len));
784 
785 	m->m_flags &= ~(M_BCAST|M_MCAST);
786 	/* encapsulated packet is forced into rdomain of physical interface */
787 	m->m_pkthdr.ph_rtableid = eth_if->if_rdomain;
788 
789 	ret = eth_if->if_output(eth_if, m, &dst, NULL);
790 	if_put(eth_if);
791 
792 	return (ret);
793 }
794 
795 /* The ioctl routine. */
796 static int
797 pppoe_ioctl(struct ifnet *ifp, unsigned long cmd, caddr_t data)
798 {
799 	struct proc *p = curproc;	/* XXX */
800 	struct pppoe_softc *sc = (struct pppoe_softc *)ifp;
801 	struct ifnet *eth_if;
802 	int error = 0;
803 
804 	switch (cmd) {
805 	case PPPOESETPARMS:
806 	{
807 		struct pppoediscparms *parms = (struct pppoediscparms *)data;
808 		int len;
809 
810 		if ((error = suser(p)) != 0)
811 			return (error);
812 		if (parms->eth_ifname[0] != '\0') {
813 			struct ifnet	*eth_if;
814 
815 			eth_if = ifunit(parms->eth_ifname);
816 			if (eth_if == NULL || eth_if->if_type != IFT_ETHER) {
817 				sc->sc_eth_ifidx = 0;
818 				return (ENXIO);
819 			}
820 
821 			if (sc->sc_sppp.pp_if.if_mtu >
822 			    eth_if->if_mtu - PPPOE_OVERHEAD) {
823 				sc->sc_sppp.pp_if.if_mtu = eth_if->if_mtu -
824 				    PPPOE_OVERHEAD;
825 			}
826 			sc->sc_eth_ifidx = eth_if->if_index;
827 		}
828 
829 		if (sc->sc_concentrator_name)
830 			free(sc->sc_concentrator_name, M_DEVBUF,
831 			    strlen(sc->sc_concentrator_name) + 1);
832 		sc->sc_concentrator_name = NULL;
833 
834 		len = strlen(parms->ac_name);
835 		if (len > 0 && len < sizeof(parms->ac_name)) {
836 			char *p = malloc(len + 1, M_DEVBUF, M_WAITOK|M_CANFAIL);
837 			if (p == NULL)
838 				return (ENOMEM);
839 			strlcpy(p, parms->ac_name, len + 1);
840 			sc->sc_concentrator_name = p;
841 		}
842 
843 		if (sc->sc_service_name)
844 			free(sc->sc_service_name, M_DEVBUF,
845 			    strlen(sc->sc_service_name) + 1);
846 		sc->sc_service_name = NULL;
847 
848 		len = strlen(parms->service_name);
849 		if (len > 0 && len < sizeof(parms->service_name)) {
850 			char *p = malloc(len + 1, M_DEVBUF, M_WAITOK|M_CANFAIL);
851 			if (p == NULL)
852 				return (ENOMEM);
853 			strlcpy(p, parms->service_name, len + 1);
854 			sc->sc_service_name = p;
855 		}
856 		return (0);
857 	}
858 	break;
859 	case PPPOEGETPARMS:
860 	{
861 		struct pppoediscparms *parms = (struct pppoediscparms *)data;
862 
863 		if ((eth_if = if_get(sc->sc_eth_ifidx)) != NULL) {
864 			strlcpy(parms->eth_ifname, eth_if->if_xname,
865 			    IFNAMSIZ);
866 			if_put(eth_if);
867 		} else
868 			parms->eth_ifname[0] = '\0';
869 
870 		if (sc->sc_concentrator_name)
871 			strlcpy(parms->ac_name, sc->sc_concentrator_name,
872 			    sizeof(parms->ac_name));
873 		else
874 			parms->ac_name[0] = '\0';
875 
876 		if (sc->sc_service_name)
877 			strlcpy(parms->service_name, sc->sc_service_name,
878 			    sizeof(parms->service_name));
879 		else
880 			parms->service_name[0] = '\0';
881 
882 		return (0);
883 	}
884 	break;
885 	case PPPOEGETSESSION:
886 	{
887 		struct pppoeconnectionstate *state =
888 		    (struct pppoeconnectionstate *)data;
889 		state->state = sc->sc_state;
890 		state->session_id = sc->sc_session;
891 		state->padi_retry_no = sc->sc_padi_retried;
892 		state->padr_retry_no = sc->sc_padr_retried;
893 		state->session_time.tv_sec = sc->sc_session_time.tv_sec;
894 		state->session_time.tv_usec = sc->sc_session_time.tv_usec;
895 		return (0);
896 	}
897 	break;
898 	case SIOCSIFFLAGS:
899 	{
900 		struct ifreq *ifr = (struct ifreq *)data;
901 		/*
902 		 * Prevent running re-establishment timers overriding
903 		 * administrators choice.
904 		 */
905 		if ((ifr->ifr_flags & IFF_UP) == 0
906 		     && sc->sc_state >= PPPOE_STATE_PADI_SENT
907 		     && sc->sc_state < PPPOE_STATE_SESSION) {
908 			timeout_del(&sc->sc_timeout);
909 			sc->sc_state = PPPOE_STATE_INITIAL;
910 			sc->sc_padi_retried = 0;
911 			sc->sc_padr_retried = 0;
912 			memcpy(&sc->sc_dest, etherbroadcastaddr,
913 			    sizeof(sc->sc_dest));
914 		}
915 		return (sppp_ioctl(ifp, cmd, data));
916 	}
917 	case SIOCSIFMTU:
918 	{
919 		struct ifreq *ifr = (struct ifreq *)data;
920 
921 		eth_if = if_get(sc->sc_eth_ifidx);
922 
923 		if (ifr->ifr_mtu > MIN(PPPOE_MAXMTU,
924 		    (eth_if == NULL ? PPPOE_MAXMTU :
925 		    (eth_if->if_mtu - PPPOE_OVERHEAD))))
926 			error = EINVAL;
927 		else
928 			error = 0;
929 
930 		if_put(eth_if);
931 
932 		return (sppp_ioctl(ifp, cmd, data));
933 	}
934 	default:
935 		error = sppp_ioctl(ifp, cmd, data);
936 		if (error == ENETRESET) {
937 			error = 0;
938 			if ((ifp->if_flags & (IFF_UP | IFF_RUNNING)) ==
939 			    (IFF_UP | IFF_RUNNING)) {
940 				if_down(ifp);
941 				if (sc->sc_state >= PPPOE_STATE_PADI_SENT &&
942 				    sc->sc_state < PPPOE_STATE_SESSION) {
943 					timeout_del(&sc->sc_timeout);
944 					sc->sc_state = PPPOE_STATE_INITIAL;
945 					sc->sc_padi_retried = 0;
946 					sc->sc_padr_retried = 0;
947 					memcpy(&sc->sc_dest,
948 					    etherbroadcastaddr,
949 					    sizeof(sc->sc_dest));
950 				}
951 				error = sppp_ioctl(ifp, SIOCSIFFLAGS, NULL);
952 				if (error)
953 					return (error);
954 				if_up(ifp);
955 				return (sppp_ioctl(ifp, SIOCSIFFLAGS, NULL));
956 			}
957 		}
958 		return (error);
959 	}
960 	return (0);
961 }
962 
963 /*
964  * Allocate a mbuf/cluster with space to store the given data length
965  * of payload, leaving space for prepending an ethernet header
966  * in front.
967  */
968 static struct mbuf *
969 pppoe_get_mbuf(size_t len)
970 {
971 	struct mbuf *m;
972 
973 	MGETHDR(m, M_DONTWAIT, MT_DATA);
974 	if (m == NULL)
975 		return (NULL);
976 	if (len + sizeof(struct ether_header) > MHLEN) {
977 		MCLGET(m, M_DONTWAIT);
978 		if ((m->m_flags & M_EXT) == 0) {
979 			m_free(m);
980 			return (NULL);
981 		}
982 	}
983 	m->m_data += sizeof(struct ether_header);
984 	m->m_len = len;
985 	m->m_pkthdr.len = len;
986 	m->m_pkthdr.ph_ifidx = 0;
987 
988 	return (m);
989 }
990 
991 /* Send PADI. */
992 static int
993 pppoe_send_padi(struct pppoe_softc *sc)
994 {
995 	struct mbuf *m0;
996 	int len, l1 = 0, l2 = 0; /* XXX: gcc */
997 	u_int8_t *p;
998 
999 	if (sc->sc_state > PPPOE_STATE_PADI_SENT)
1000 		panic("pppoe_send_padi in state %d", sc->sc_state);
1001 
1002 	/* calculate length of frame (excluding ethernet header + pppoe header) */
1003 	len = 2 + 2 + 2 + 2 + sizeof(sc->sc_unique); /* service name tag is required, host unique is sent too */
1004 	if (sc->sc_service_name != NULL) {
1005 		l1 = strlen(sc->sc_service_name);
1006 		len += l1;
1007 	}
1008 	if (sc->sc_concentrator_name != NULL) {
1009 		l2 = strlen(sc->sc_concentrator_name);
1010 		len += 2 + 2 + l2;
1011 	}
1012 	if (sc->sc_sppp.pp_if.if_mtu > PPPOE_MTU)
1013 		len += 2 + 2 + 2;
1014 
1015 	/* allocate a buffer */
1016 	m0 = pppoe_get_mbuf(len + PPPOE_HEADERLEN);	/* header len + payload len */
1017 	if (m0 == NULL)
1018 		return (ENOBUFS);
1019 	m0->m_pkthdr.pf.prio = sc->sc_sppp.pp_if.if_llprio;
1020 
1021 	/* fill in pkt */
1022 	p = mtod(m0, u_int8_t *);
1023 	PPPOE_ADD_HEADER(p, PPPOE_CODE_PADI, 0, len);
1024 	PPPOE_ADD_16(p, PPPOE_TAG_SNAME);
1025 	if (sc->sc_service_name != NULL) {
1026 		PPPOE_ADD_16(p, l1);
1027 		memcpy(p, sc->sc_service_name, l1);
1028 		p += l1;
1029 	} else {
1030 		PPPOE_ADD_16(p, 0);
1031 	}
1032 	if (sc->sc_concentrator_name != NULL) {
1033 		PPPOE_ADD_16(p, PPPOE_TAG_ACNAME);
1034 		PPPOE_ADD_16(p, l2);
1035 		memcpy(p, sc->sc_concentrator_name, l2);
1036 		p += l2;
1037 	}
1038 	PPPOE_ADD_16(p, PPPOE_TAG_HUNIQUE);
1039 	PPPOE_ADD_16(p, sizeof(sc->sc_unique));
1040 	memcpy(p, &sc->sc_unique, sizeof(sc->sc_unique));
1041 	p += sizeof(sc->sc_unique);
1042 
1043 	if (sc->sc_sppp.pp_if.if_mtu > PPPOE_MTU) {
1044 		PPPOE_ADD_16(p, PPPOE_TAG_MAX_PAYLOAD);
1045 		PPPOE_ADD_16(p, 2);
1046 		PPPOE_ADD_16(p, (u_int16_t)sc->sc_sppp.pp_if.if_mtu);
1047 	}
1048 
1049 #ifdef PPPOE_DEBUG
1050 	if (p - mtod(m0, u_int8_t *) != len + PPPOE_HEADERLEN)
1051 		panic("pppoe_send_padi: garbled output len, should be %ld, is %ld",
1052 		    (long)(len + PPPOE_HEADERLEN), (long)(p - mtod(m0, u_int8_t *)));
1053 #endif
1054 
1055 	/* send pkt */
1056 	return (pppoe_output(sc, m0));
1057 }
1058 
1059 /* Watchdog function. */
1060 static void
1061 pppoe_timeout(void *arg)
1062 {
1063 	struct pppoe_softc *sc = (struct pppoe_softc *)arg;
1064 	int x, retry_wait, err;
1065 
1066 	PPPOEDEBUG(("%s: timeout\n", sc->sc_sppp.pp_if.if_xname));
1067 
1068 	NET_LOCK();
1069 
1070 	switch (sc->sc_state) {
1071 	case PPPOE_STATE_PADI_SENT:
1072 		/*
1073 		 * We have two basic ways of retrying:
1074 		 *  - Quick retry mode: try a few times in short sequence
1075 		 *  - Slow retry mode: we already had a connection successfully
1076 		 *    established and will try infinitely (without user
1077 		 *    intervention)
1078 		 * We only enter slow retry mode if IFF_LINK1 (aka autodial)
1079 		 * is not set.
1080 		 */
1081 
1082 		/* initialize for quick retry mode */
1083 		retry_wait = PPPOE_DISC_TIMEOUT * (1 + sc->sc_padi_retried);
1084 
1085 		x = splnet();
1086 		sc->sc_padi_retried++;
1087 		if (sc->sc_padi_retried >= PPPOE_DISC_MAXPADI) {
1088 			if ((sc->sc_sppp.pp_if.if_flags & IFF_LINK1) == 0) {
1089 				/* slow retry mode */
1090 				retry_wait = PPPOE_SLOW_RETRY;
1091 			} else {
1092 				pppoe_abort_connect(sc);
1093 				splx(x);
1094 				break;
1095 			}
1096 		}
1097 		if ((err = pppoe_send_padi(sc)) != 0) {
1098 			sc->sc_padi_retried--;
1099 			PPPOEDEBUG(("%s: failed to transmit PADI, error=%d\n",
1100 			    sc->sc_sppp.pp_if.if_xname, err));
1101 		}
1102 		timeout_add_sec(&sc->sc_timeout, retry_wait);
1103 		splx(x);
1104 
1105 		break;
1106 	case PPPOE_STATE_PADR_SENT:
1107 		x = splnet();
1108 		sc->sc_padr_retried++;
1109 		if (sc->sc_padr_retried >= PPPOE_DISC_MAXPADR) {
1110 			memcpy(&sc->sc_dest, etherbroadcastaddr,
1111 			    sizeof(sc->sc_dest));
1112 			sc->sc_state = PPPOE_STATE_PADI_SENT;
1113 			sc->sc_padr_retried = 0;
1114 			if ((err = pppoe_send_padi(sc)) != 0) {
1115 				PPPOEDEBUG(("%s: failed to send PADI, error=%d\n",
1116 				    sc->sc_sppp.pp_if.if_xname, err));
1117 			}
1118 			timeout_add_sec(&sc->sc_timeout,
1119 			    PPPOE_DISC_TIMEOUT * (1 + sc->sc_padi_retried));
1120 			splx(x);
1121 			break;
1122 		}
1123 		if ((err = pppoe_send_padr(sc)) != 0) {
1124 			sc->sc_padr_retried--;
1125 			PPPOEDEBUG(("%s: failed to send PADR, error=%d\n",
1126 			    sc->sc_sppp.pp_if.if_xname, err));
1127 		}
1128 		timeout_add_sec(&sc->sc_timeout,
1129 		    PPPOE_DISC_TIMEOUT * (1 + sc->sc_padr_retried));
1130 		splx(x);
1131 
1132 		break;
1133 	case PPPOE_STATE_CLOSING:
1134 		pppoe_disconnect(sc);
1135 		break;
1136 	default:
1137 		break;	/* all done, work in peace */
1138 	}
1139 
1140 	NET_UNLOCK();
1141 }
1142 
1143 /* Start a connection (i.e. initiate discovery phase). */
1144 static int
1145 pppoe_connect(struct pppoe_softc *sc)
1146 {
1147 	int x, err;
1148 
1149 	if (sc->sc_state != PPPOE_STATE_INITIAL)
1150 		return (EBUSY);
1151 
1152 	x = splnet();
1153 
1154 	/* save state, in case we fail to send PADI */
1155 	sc->sc_state = PPPOE_STATE_PADI_SENT;
1156 	sc->sc_padr_retried = 0;
1157 	err = pppoe_send_padi(sc);
1158 	if (err != 0)
1159 		PPPOEDEBUG(("%s: failed to send PADI, error=%d\n",
1160 		    sc->sc_sppp.pp_if.if_xname, err));
1161 
1162 	timeout_add_sec(&sc->sc_timeout, PPPOE_DISC_TIMEOUT);
1163 	splx(x);
1164 
1165 	return (err);
1166 }
1167 
1168 /* disconnect */
1169 static int
1170 pppoe_disconnect(struct pppoe_softc *sc)
1171 {
1172 	int err, x;
1173 
1174 	x = splnet();
1175 
1176 	if (sc->sc_state < PPPOE_STATE_SESSION)
1177 		err = EBUSY;
1178 	else {
1179 		PPPOEDEBUG(("%s: disconnecting\n",
1180 		    sc->sc_sppp.pp_if.if_xname));
1181 		err = pppoe_send_padt(sc->sc_eth_ifidx,
1182 		    sc->sc_session, (const u_int8_t *)&sc->sc_dest,
1183 		    sc->sc_sppp.pp_if.if_llprio);
1184 	}
1185 
1186 	/* cleanup softc */
1187 	sc->sc_state = PPPOE_STATE_INITIAL;
1188 	memcpy(&sc->sc_dest, etherbroadcastaddr, sizeof(sc->sc_dest));
1189 	if (sc->sc_ac_cookie) {
1190 		free(sc->sc_ac_cookie, M_DEVBUF, sc->sc_ac_cookie_len);
1191 		sc->sc_ac_cookie = NULL;
1192 	}
1193 	sc->sc_ac_cookie_len = 0;
1194 	if (sc->sc_relay_sid) {
1195 		free(sc->sc_relay_sid, M_DEVBUF, sc->sc_relay_sid_len);
1196 		sc->sc_relay_sid = NULL;
1197 	}
1198 	sc->sc_relay_sid_len = 0;
1199 	sc->sc_session = 0;
1200 
1201 	/* notify upper layer */
1202 	sc->sc_sppp.pp_down(&sc->sc_sppp);
1203 
1204 	splx(x);
1205 
1206 	return (err);
1207 }
1208 
1209 /* Connection attempt aborted. */
1210 static void
1211 pppoe_abort_connect(struct pppoe_softc *sc)
1212 {
1213 	printf("%s: could not establish connection\n",
1214 		sc->sc_sppp.pp_if.if_xname);
1215 	sc->sc_state = PPPOE_STATE_CLOSING;
1216 
1217 	/* notify upper layer */
1218 	sc->sc_sppp.pp_down(&sc->sc_sppp);
1219 
1220 	/* clear connection state */
1221 	memcpy(&sc->sc_dest, etherbroadcastaddr, sizeof(sc->sc_dest));
1222 	sc->sc_state = PPPOE_STATE_INITIAL;
1223 }
1224 
1225 /* Send a PADR packet */
1226 static int
1227 pppoe_send_padr(struct pppoe_softc *sc)
1228 {
1229 	struct mbuf *m0;
1230 	u_int8_t *p;
1231 	size_t len, l1 = 0; /* XXX: gcc */
1232 
1233 	if (sc->sc_state != PPPOE_STATE_PADR_SENT)
1234 		return (EIO);
1235 
1236 	len = 2 + 2 + 2 + 2 + sizeof(sc->sc_unique);	/* service name, host unique */
1237 	if (sc->sc_service_name != NULL) {		/* service name tag maybe empty */
1238 		l1 = strlen(sc->sc_service_name);
1239 		len += l1;
1240 	}
1241 	if (sc->sc_ac_cookie_len > 0)
1242 		len += 2 + 2 + sc->sc_ac_cookie_len;	/* AC cookie */
1243 	if (sc->sc_relay_sid_len > 0)
1244 		len += 2 + 2 + sc->sc_relay_sid_len;	/* Relay SID */
1245 	if (sc->sc_sppp.pp_if.if_mtu > PPPOE_MTU)
1246 		len += 2 + 2 + 2;
1247 
1248 	m0 = pppoe_get_mbuf(len + PPPOE_HEADERLEN);
1249 	if (m0 == NULL)
1250 		return (ENOBUFS);
1251 	m0->m_pkthdr.pf.prio = sc->sc_sppp.pp_if.if_llprio;
1252 
1253 	p = mtod(m0, u_int8_t *);
1254 	PPPOE_ADD_HEADER(p, PPPOE_CODE_PADR, 0, len);
1255 	PPPOE_ADD_16(p, PPPOE_TAG_SNAME);
1256 
1257 	if (sc->sc_service_name != NULL) {
1258 		PPPOE_ADD_16(p, l1);
1259 		memcpy(p, sc->sc_service_name, l1);
1260 		p += l1;
1261 	} else {
1262 		PPPOE_ADD_16(p, 0);
1263 	}
1264 	if (sc->sc_ac_cookie_len > 0) {
1265 		PPPOE_ADD_16(p, PPPOE_TAG_ACCOOKIE);
1266 		PPPOE_ADD_16(p, sc->sc_ac_cookie_len);
1267 		memcpy(p, sc->sc_ac_cookie, sc->sc_ac_cookie_len);
1268 		p += sc->sc_ac_cookie_len;
1269 	}
1270 	if (sc->sc_relay_sid_len > 0) {
1271 		PPPOE_ADD_16(p, PPPOE_TAG_RELAYSID);
1272 		PPPOE_ADD_16(p, sc->sc_relay_sid_len);
1273 		memcpy(p, sc->sc_relay_sid, sc->sc_relay_sid_len);
1274 		p += sc->sc_relay_sid_len;
1275 	}
1276 	PPPOE_ADD_16(p, PPPOE_TAG_HUNIQUE);
1277 	PPPOE_ADD_16(p, sizeof(sc->sc_unique));
1278 	memcpy(p, &sc->sc_unique, sizeof(sc->sc_unique));
1279 	p += sizeof(sc->sc_unique);
1280 
1281 	if (sc->sc_sppp.pp_if.if_mtu > PPPOE_MTU) {
1282 		PPPOE_ADD_16(p, PPPOE_TAG_MAX_PAYLOAD);
1283 		PPPOE_ADD_16(p, 2);
1284 		PPPOE_ADD_16(p, (u_int16_t)sc->sc_sppp.pp_if.if_mtu);
1285 	}
1286 
1287 #ifdef PPPOE_DEBUG
1288 	if (p - mtod(m0, u_int8_t *) != len + PPPOE_HEADERLEN)
1289 		panic("pppoe_send_padr: garbled output len, should be %ld, is %ld",
1290 			(long)(len + PPPOE_HEADERLEN), (long)(p - mtod(m0, u_int8_t *)));
1291 #endif
1292 
1293 	return (pppoe_output(sc, m0));
1294 }
1295 
1296 /* Send a PADT packet. */
1297 static int
1298 pppoe_send_padt(unsigned int ifidx, u_int session, const u_int8_t *dest, u_int8_t prio)
1299 {
1300 	struct ether_header *eh;
1301 	struct sockaddr dst;
1302 	struct ifnet *eth_if;
1303 	struct mbuf *m0;
1304 	u_int8_t *p;
1305 	int ret;
1306 
1307 	if ((eth_if = if_get(ifidx)) == NULL)
1308 		return (EINVAL);
1309 
1310 	m0 = pppoe_get_mbuf(PPPOE_HEADERLEN);
1311 	if (m0 == NULL) {
1312 		if_put(eth_if);
1313 		return (ENOBUFS);
1314 	}
1315 	m0->m_pkthdr.pf.prio = prio;
1316 
1317 	p = mtod(m0, u_int8_t *);
1318 	PPPOE_ADD_HEADER(p, PPPOE_CODE_PADT, session, 0);
1319 
1320 	memset(&dst, 0, sizeof(dst));
1321 	dst.sa_family = AF_UNSPEC;
1322 	eh = (struct ether_header *)&dst.sa_data;
1323 	eh->ether_type = htons(ETHERTYPE_PPPOEDISC);
1324 	memcpy(&eh->ether_dhost, dest, ETHER_ADDR_LEN);
1325 
1326 	m0->m_flags &= ~(M_BCAST|M_MCAST);
1327 	/* encapsulated packet is forced into rdomain of physical interface */
1328 	m0->m_pkthdr.ph_rtableid = eth_if->if_rdomain;
1329 
1330 	ret = eth_if->if_output(eth_if, m0, &dst, NULL);
1331 	if_put(eth_if);
1332 
1333 	return (ret);
1334 }
1335 
1336 
1337 /* this-layer-start function */
1338 static void
1339 pppoe_tls(struct sppp *sp)
1340 {
1341 	struct pppoe_softc *sc = (void *)sp;
1342 
1343 	if (sc->sc_state != PPPOE_STATE_INITIAL)
1344 		return;
1345 	pppoe_connect(sc);
1346 }
1347 
1348 /* this-layer-finish function */
1349 static void
1350 pppoe_tlf(struct sppp *sp)
1351 {
1352 	struct pppoe_softc *sc = (void *)sp;
1353 
1354 	if (sc->sc_state < PPPOE_STATE_SESSION)
1355 		return;
1356 	/*
1357 	 * Do not call pppoe_disconnect here, the upper layer state
1358 	 * machine gets confused by this. We must return from this
1359 	 * function and defer disconnecting to the timeout handler.
1360 	 */
1361 	sc->sc_state = PPPOE_STATE_CLOSING;
1362 	timeout_add_msec(&sc->sc_timeout, 20);
1363 }
1364 
1365 static void
1366 pppoe_start(struct ifnet *ifp)
1367 {
1368 	struct pppoe_softc *sc = (void *)ifp;
1369 	struct mbuf *m;
1370 	size_t len;
1371 	u_int8_t *p;
1372 
1373 	if (sppp_isempty(ifp))
1374 		return;
1375 
1376 	/* are we ready to process data yet? */
1377 	if (sc->sc_state < PPPOE_STATE_SESSION) {
1378 		sppp_flush(&sc->sc_sppp.pp_if);
1379 		return;
1380 	}
1381 
1382 	while ((m = sppp_dequeue(ifp)) != NULL) {
1383 		len = m->m_pkthdr.len;
1384 		M_PREPEND(m, PPPOE_HEADERLEN, M_DONTWAIT);
1385 		if (m == NULL) {
1386 			ifp->if_oerrors++;
1387 			continue;
1388 		}
1389 		p = mtod(m, u_int8_t *);
1390 		PPPOE_ADD_HEADER(p, 0, sc->sc_session, len);
1391 
1392 #if NBPFILTER > 0
1393 		if(sc->sc_sppp.pp_if.if_bpf)
1394 			bpf_mtap(sc->sc_sppp.pp_if.if_bpf, m,
1395 			    BPF_DIRECTION_OUT);
1396 #endif
1397 
1398 		pppoe_output(sc, m);
1399 	}
1400 }
1401