1 /*
2  * ipv6cp.c - PPP IPV6 Control Protocol.
3  *
4  * Copyright (c) 1999 Tommi Komulainen.  All rights reserved.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  *
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  *
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in
15  *    the documentation and/or other materials provided with the
16  *    distribution.
17  *
18  * 3. The name(s) of the authors of this software must not be used to
19  *    endorse or promote products derived from this software without
20  *    prior written permission.
21  *
22  * 4. Redistributions of any form whatsoever must retain the following
23  *    acknowledgment:
24  *    "This product includes software developed by Tommi Komulainen
25  *     <Tommi.Komulainen@iki.fi>".
26  *
27  * THE AUTHORS OF THIS SOFTWARE DISCLAIM ALL WARRANTIES WITH REGARD TO
28  * THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
29  * AND FITNESS, IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY
30  * SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
31  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN
32  * AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING
33  * OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
34  *
35  */
36 
37 /*  Original version, based on RFC2023 :
38 
39     Copyright (c) 1995, 1996, 1997 Francis.Dupont@inria.fr, INRIA Rocquencourt,
40     Alain.Durand@imag.fr, IMAG,
41     Jean-Luc.Richier@imag.fr, IMAG-LSR.
42 
43     Copyright (c) 1998, 1999 Francis.Dupont@inria.fr, GIE DYADE,
44     Alain.Durand@imag.fr, IMAG,
45     Jean-Luc.Richier@imag.fr, IMAG-LSR.
46 
47     Ce travail a été fait au sein du GIE DYADE (Groupement d'Intérêt
48     Économique ayant pour membres BULL S.A. et l'INRIA).
49 
50     Ce logiciel informatique est disponible aux conditions
51     usuelles dans la recherche, c'est-à-dire qu'il peut
52     être utilisé, copié, modifié, distribué à l'unique
53     condition que ce texte soit conservé afin que
54     l'origine de ce logiciel soit reconnue.
55 
56     Le nom de l'Institut National de Recherche en Informatique
57     et en Automatique (INRIA), de l'IMAG, ou d'une personne morale
58     ou physique ayant participé à l'élaboration de ce logiciel ne peut
59     être utilisé sans son accord préalable explicite.
60 
61     Ce logiciel est fourni tel quel sans aucune garantie,
62     support ou responsabilité d'aucune sorte.
63     Ce logiciel est dérivé de sources d'origine
64     "University of California at Berkeley" et
65     "Digital Equipment Corporation" couvertes par des copyrights.
66 
67     L'Institut d'Informatique et de Mathématiques Appliquées de Grenoble (IMAG)
68     est une fédération d'unités mixtes de recherche du CNRS, de l'Institut National
69     Polytechnique de Grenoble et de l'Université Joseph Fourier regroupant
70     sept laboratoires dont le laboratoire Logiciels, Systèmes, Réseaux (LSR).
71 
72     This work has been done in the context of GIE DYADE (joint R & D venture
73     between BULL S.A. and INRIA).
74 
75     This software is available with usual "research" terms
76     with the aim of retain credits of the software.
77     Permission to use, copy, modify and distribute this software for any
78     purpose and without fee is hereby granted, provided that the above
79     copyright notice and this permission notice appear in all copies,
80     and the name of INRIA, IMAG, or any contributor not be used in advertising
81     or publicity pertaining to this material without the prior explicit
82     permission. The software is provided "as is" without any
83     warranties, support or liabilities of any kind.
84     This software is derived from source code from
85     "University of California at Berkeley" and
86     "Digital Equipment Corporation" protected by copyrights.
87 
88     Grenoble's Institute of Computer Science and Applied Mathematics (IMAG)
89     is a federation of seven research units funded by the CNRS, National
90     Polytechnic Institute of Grenoble and University Joseph Fourier.
91     The research unit in Software, Systems, Networks (LSR) is member of IMAG.
92 */
93 
94 /*
95  * Derived from :
96  *
97  *
98  * ipcp.c - PPP IP Control Protocol.
99  *
100  * Copyright (c) 1984-2000 Carnegie Mellon University. All rights reserved.
101  *
102  * Redistribution and use in source and binary forms, with or without
103  * modification, are permitted provided that the following conditions
104  * are met:
105  *
106  * 1. Redistributions of source code must retain the above copyright
107  *    notice, this list of conditions and the following disclaimer.
108  *
109  * 2. Redistributions in binary form must reproduce the above copyright
110  *    notice, this list of conditions and the following disclaimer in
111  *    the documentation and/or other materials provided with the
112  *    distribution.
113  *
114  * 3. The name "Carnegie Mellon University" must not be used to
115  *    endorse or promote products derived from this software without
116  *    prior written permission. For permission or any legal
117  *    details, please contact
118  *      Office of Technology Transfer
119  *      Carnegie Mellon University
120  *      5000 Forbes Avenue
121  *      Pittsburgh, PA  15213-3890
122  *      (412) 268-4387, fax: (412) 268-7395
123  *      tech-transfer@andrew.cmu.edu
124  *
125  * 4. Redistributions of any form whatsoever must retain the following
126  *    acknowledgment:
127  *    "This product includes software developed by Computing Services
128  *     at Carnegie Mellon University (http://www.cmu.edu/computing/)."
129  *
130  * CARNEGIE MELLON UNIVERSITY DISCLAIMS ALL WARRANTIES WITH REGARD TO
131  * THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
132  * AND FITNESS, IN NO EVENT SHALL CARNEGIE MELLON UNIVERSITY BE LIABLE
133  * FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
134  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN
135  * AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING
136  * OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
137  *
138  * $Id: ipv6cp.c,v 1.21 2005/08/25 23:59:34 paulus Exp $
139  */
140 
141 /*
142  * @todo:
143  *
144  * Proxy Neighbour Discovery.
145  *
146  * Better defines for selecting the ordering of
147  *   interface up / set address.
148  */
149 
150 #include "netif/ppp/ppp_opts.h"
151 #if PPP_SUPPORT && PPP_IPV6_SUPPORT  /* don't build if not configured for use in lwipopts.h */
152 
153 #if 0 /* UNUSED */
154 #include <stdio.h>
155 #include <string.h>
156 #include <unistd.h>
157 #include <netdb.h>
158 #include <sys/param.h>
159 #include <sys/types.h>
160 #include <sys/socket.h>
161 #include <netinet/in.h>
162 #include <arpa/inet.h>
163 #endif /* UNUSED */
164 
165 #include "netif/ppp/ppp_impl.h"
166 #include "netif/ppp/fsm.h"
167 #include "netif/ppp/ipcp.h"
168 #include "netif/ppp/ipv6cp.h"
169 #include "netif/ppp/magic.h"
170 
171 /* global vars */
172 #if 0 /* UNUSED */
173 int no_ifaceid_neg = 0;
174 #endif /* UNUSED */
175 
176 /*
177  * Callbacks for fsm code.  (CI = Configuration Information)
178  */
179 static void ipv6cp_resetci(fsm *f); /* Reset our CI */
180 static int  ipv6cp_cilen(fsm *f); /* Return length of our CI */
181 static void ipv6cp_addci(fsm *f, u_char *ucp, int *lenp); /* Add our CI */
182 static int  ipv6cp_ackci(fsm *f, u_char *p, int len); /* Peer ack'd our CI */
183 static int  ipv6cp_nakci(fsm *f, u_char *p, int len, int treat_as_reject); /* Peer nak'd our CI */
184 static int  ipv6cp_rejci(fsm *f, u_char *p, int len); /* Peer rej'd our CI */
185 static int  ipv6cp_reqci(fsm *f, u_char *inp, int *len, int reject_if_disagree); /* Rcv CI */
186 static void ipv6cp_up(fsm *f); /* We're UP */
187 static void ipv6cp_down(fsm *f); /* We're DOWN */
188 static void ipv6cp_finished(fsm *f); /* Don't need lower layer */
189 
190 static const fsm_callbacks ipv6cp_callbacks = { /* IPV6CP callback routines */
191     ipv6cp_resetci,		/* Reset our Configuration Information */
192     ipv6cp_cilen,		/* Length of our Configuration Information */
193     ipv6cp_addci,		/* Add our Configuration Information */
194     ipv6cp_ackci,		/* ACK our Configuration Information */
195     ipv6cp_nakci,		/* NAK our Configuration Information */
196     ipv6cp_rejci,		/* Reject our Configuration Information */
197     ipv6cp_reqci,		/* Request peer's Configuration Information */
198     ipv6cp_up,			/* Called when fsm reaches OPENED state */
199     ipv6cp_down,		/* Called when fsm leaves OPENED state */
200     NULL,			/* Called when we want the lower layer up */
201     ipv6cp_finished,		/* Called when we want the lower layer down */
202     NULL,			/* Called when Protocol-Reject received */
203     NULL,			/* Retransmission is necessary */
204     NULL,			/* Called to handle protocol-specific codes */
205     "IPV6CP"			/* String name of protocol */
206 };
207 
208 #if PPP_OPTIONS
209 /*
210  * Command-line options.
211  */
212 static int setifaceid(char **arg));
213 static void printifaceid(option_t *,
214 			      void (*)(void *, char *, ...), void *));
215 
216 static option_t ipv6cp_option_list[] = {
217     { "ipv6", o_special, (void *)setifaceid,
218       "Set interface identifiers for IPV6",
219       OPT_A2PRINTER, (void *)printifaceid },
220 
221     { "+ipv6", o_bool, &ipv6cp_protent.enabled_flag,
222       "Enable IPv6 and IPv6CP", OPT_PRIO | 1 },
223     { "noipv6", o_bool, &ipv6cp_protent.enabled_flag,
224       "Disable IPv6 and IPv6CP", OPT_PRIOSUB },
225     { "-ipv6", o_bool, &ipv6cp_protent.enabled_flag,
226       "Disable IPv6 and IPv6CP", OPT_PRIOSUB | OPT_ALIAS },
227 
228     { "ipv6cp-accept-local", o_bool, &ipv6cp_allowoptions[0].accept_local,
229       "Accept peer's interface identifier for us", 1 },
230 
231     { "ipv6cp-use-ipaddr", o_bool, &ipv6cp_allowoptions[0].use_ip,
232       "Use (default) IPv4 address as interface identifier", 1 },
233 
234     { "ipv6cp-use-persistent", o_bool, &ipv6cp_wantoptions[0].use_persistent,
235       "Use uniquely-available persistent value for link local address", 1 },
236 
237     { "ipv6cp-restart", o_int, &ipv6cp_fsm[0].timeouttime,
238       "Set timeout for IPv6CP", OPT_PRIO },
239     { "ipv6cp-max-terminate", o_int, &ipv6cp_fsm[0].maxtermtransmits,
240       "Set max #xmits for term-reqs", OPT_PRIO },
241     { "ipv6cp-max-configure", o_int, &ipv6cp_fsm[0].maxconfreqtransmits,
242       "Set max #xmits for conf-reqs", OPT_PRIO },
243     { "ipv6cp-max-failure", o_int, &ipv6cp_fsm[0].maxnakloops,
244       "Set max #conf-naks for IPv6CP", OPT_PRIO },
245 
246    { NULL }
247 };
248 #endif /* PPP_OPTIONS */
249 
250 /*
251  * Protocol entry points from main code.
252  */
253 static void ipv6cp_init(ppp_pcb *pcb);
254 static void ipv6cp_open(ppp_pcb *pcb);
255 static void ipv6cp_close(ppp_pcb *pcb, const char *reason);
256 static void ipv6cp_lowerup(ppp_pcb *pcb);
257 static void ipv6cp_lowerdown(ppp_pcb *pcb);
258 static void ipv6cp_input(ppp_pcb *pcb, u_char *p, int len);
259 static void ipv6cp_protrej(ppp_pcb *pcb);
260 #if PPP_OPTIONS
261 static void ipv6_check_options(void);
262 #endif /* PPP_OPTIONS */
263 #if DEMAND_SUPPORT
264 static int  ipv6_demand_conf(int u);
265 #endif /* DEMAND_SUPPORT */
266 #if PRINTPKT_SUPPORT
267 static int ipv6cp_printpkt(const u_char *p, int plen,
268 		void (*printer)(void *, const char *, ...), void *arg);
269 #endif /* PRINTPKT_SUPPORT */
270 #if DEMAND_SUPPORT
271 static int ipv6_active_pkt(u_char *pkt, int len);
272 #endif /* DEMAND_SUPPORT */
273 
274 const struct protent ipv6cp_protent = {
275     PPP_IPV6CP,
276     ipv6cp_init,
277     ipv6cp_input,
278     ipv6cp_protrej,
279     ipv6cp_lowerup,
280     ipv6cp_lowerdown,
281     ipv6cp_open,
282     ipv6cp_close,
283 #if PRINTPKT_SUPPORT
284     ipv6cp_printpkt,
285 #endif /* PRINTPKT_SUPPORT */
286 #if PPP_DATAINPUT
287     NULL,
288 #endif /* PPP_DATAINPUT */
289 #if PRINTPKT_SUPPORT
290     "IPV6CP",
291     "IPV6",
292 #endif /* PRINTPKT_SUPPORT */
293 #if PPP_OPTIONS
294     ipv6cp_option_list,
295     ipv6_check_options,
296 #endif /* PPP_OPTIONS */
297 #if DEMAND_SUPPORT
298     ipv6_demand_conf,
299     ipv6_active_pkt
300 #endif /* DEMAND_SUPPORT */
301 };
302 
303 static void ipv6cp_clear_addrs(ppp_pcb *pcb, eui64_t ourid, eui64_t hisid);
304 #if 0 /* UNUSED */
305 static void ipv6cp_script(char *));
306 static void ipv6cp_script_done(void *));
307 #endif /* UNUSED */
308 
309 /*
310  * Lengths of configuration options.
311  */
312 #define CILEN_VOID	2
313 #define CILEN_COMPRESS	4	/* length for RFC2023 compress opt. */
314 #define CILEN_IFACEID   10	/* RFC2472, interface identifier    */
315 
316 #define CODENAME(x)	((x) == CONFACK ? "ACK" : \
317 			 (x) == CONFNAK ? "NAK" : "REJ")
318 
319 #if 0 /* UNUSED */
320 /*
321  * This state variable is used to ensure that we don't
322  * run an ipcp-up/down script while one is already running.
323  */
324 static enum script_state {
325     s_down,
326     s_up,
327 } ipv6cp_script_state;
328 static pid_t ipv6cp_script_pid;
329 #endif /* UNUSED */
330 
331 static char *llv6_ntoa(eui64_t ifaceid);
332 
333 #if PPP_OPTIONS
334 /*
335  * setifaceid - set the interface identifiers manually
336  */
337 static int
setifaceid(argv)338 setifaceid(argv)
339     char **argv;
340 {
341     char *comma, *arg, c;
342     ipv6cp_options *wo = &ipv6cp_wantoptions[0];
343     struct in6_addr addr;
344     static int prio_local, prio_remote;
345 
346 #define VALIDID(a) ( (((a).s6_addr32[0] == 0) && ((a).s6_addr32[1] == 0)) && \
347 			(((a).s6_addr32[2] != 0) || ((a).s6_addr32[3] != 0)) )
348 
349     arg = *argv;
350     if ((comma = strchr(arg, ',')) == NULL)
351 	comma = arg + strlen(arg);
352 
353     /*
354      * If comma first character, then no local identifier
355      */
356     if (comma != arg) {
357 	c = *comma;
358 	*comma = '\0';
359 
360 	if (inet_pton(AF_INET6, arg, &addr) == 0 || !VALIDID(addr)) {
361 	    option_error("Illegal interface identifier (local): %s", arg);
362 	    return 0;
363 	}
364 
365 	if (option_priority >= prio_local) {
366 	    eui64_copy(addr.s6_addr32[2], wo->ourid);
367 	    wo->opt_local = 1;
368 	    prio_local = option_priority;
369 	}
370 	*comma = c;
371     }
372 
373     /*
374      * If comma last character, the no remote identifier
375      */
376     if (*comma != 0 && *++comma != '\0') {
377 	if (inet_pton(AF_INET6, comma, &addr) == 0 || !VALIDID(addr)) {
378 	    option_error("Illegal interface identifier (remote): %s", comma);
379 	    return 0;
380 	}
381 	if (option_priority >= prio_remote) {
382 	    eui64_copy(addr.s6_addr32[2], wo->hisid);
383 	    wo->opt_remote = 1;
384 	    prio_remote = option_priority;
385 	}
386     }
387 
388     if (override_value("+ipv6", option_priority, option_source))
389 	ipv6cp_protent.enabled_flag = 1;
390     return 1;
391 }
392 
393 static void
394 printifaceid(opt, printer, arg)
395     option_t *opt;
396     void (*printer)(void *, char *, ...));
397     void *arg;
398 {
399 	ipv6cp_options *wo = &ipv6cp_wantoptions[0];
400 
401 	if (wo->opt_local)
402 		printer(arg, "%s", llv6_ntoa(wo->ourid));
403 	printer(arg, ",");
404 	if (wo->opt_remote)
405 		printer(arg, "%s", llv6_ntoa(wo->hisid));
406 }
407 #endif /* PPP_OPTIONS */
408 
409 /*
410  * Make a string representation of a network address.
411  */
412 static char *
413 llv6_ntoa(eui64_t ifaceid)
414 {
415     static char b[26];
416 
417     sprintf(b, "fe80::%02x%02x:%02x%02x:%02x%02x:%02x%02x",
418       ifaceid.e8[0], ifaceid.e8[1], ifaceid.e8[2], ifaceid.e8[3],
419       ifaceid.e8[4], ifaceid.e8[5], ifaceid.e8[6], ifaceid.e8[7]);
420 
421     return b;
422 }
423 
424 
425 /*
426  * ipv6cp_init - Initialize IPV6CP.
427  */
428 static void ipv6cp_init(ppp_pcb *pcb) {
429     fsm *f = &pcb->ipv6cp_fsm;
430     ipv6cp_options *wo = &pcb->ipv6cp_wantoptions;
431     ipv6cp_options *ao = &pcb->ipv6cp_allowoptions;
432 
433     f->pcb = pcb;
434     f->protocol = PPP_IPV6CP;
435     f->callbacks = &ipv6cp_callbacks;
436     fsm_init(f);
437 
438 #if 0 /* Not necessary, everything is cleared in ppp_new() */
439     memset(wo, 0, sizeof(*wo));
440     memset(ao, 0, sizeof(*ao));
441 #endif /* 0 */
442 
443     wo->accept_local = 1;
444     wo->neg_ifaceid = 1;
445     ao->neg_ifaceid = 1;
446 
447 #ifdef IPV6CP_COMP
448     wo->neg_vj = 1;
449     ao->neg_vj = 1;
450     wo->vj_protocol = IPV6CP_COMP;
451 #endif
452 
453 }
454 
455 
456 /*
457  * ipv6cp_open - IPV6CP is allowed to come up.
458  */
459 static void ipv6cp_open(ppp_pcb *pcb) {
460     fsm_open(&pcb->ipv6cp_fsm);
461 }
462 
463 
464 /*
465  * ipv6cp_close - Take IPV6CP down.
466  */
467 static void ipv6cp_close(ppp_pcb *pcb, const char *reason) {
468     fsm_close(&pcb->ipv6cp_fsm, reason);
469 }
470 
471 
472 /*
473  * ipv6cp_lowerup - The lower layer is up.
474  */
475 static void ipv6cp_lowerup(ppp_pcb *pcb) {
476     fsm_lowerup(&pcb->ipv6cp_fsm);
477 }
478 
479 
480 /*
481  * ipv6cp_lowerdown - The lower layer is down.
482  */
483 static void ipv6cp_lowerdown(ppp_pcb *pcb) {
484     fsm_lowerdown(&pcb->ipv6cp_fsm);
485 }
486 
487 
488 /*
489  * ipv6cp_input - Input IPV6CP packet.
490  */
491 static void ipv6cp_input(ppp_pcb *pcb, u_char *p, int len) {
492     fsm_input(&pcb->ipv6cp_fsm, p, len);
493 }
494 
495 
496 /*
497  * ipv6cp_protrej - A Protocol-Reject was received for IPV6CP.
498  *
499  * Pretend the lower layer went down, so we shut up.
500  */
501 static void ipv6cp_protrej(ppp_pcb *pcb) {
502     fsm_lowerdown(&pcb->ipv6cp_fsm);
503 }
504 
505 
506 /*
507  * ipv6cp_resetci - Reset our CI.
508  */
509 static void ipv6cp_resetci(fsm *f) {
510     ppp_pcb *pcb = f->pcb;
511     ipv6cp_options *wo = &pcb->ipv6cp_wantoptions;
512     ipv6cp_options *go = &pcb->ipv6cp_gotoptions;
513     ipv6cp_options *ao = &pcb->ipv6cp_allowoptions;
514 
515     wo->req_ifaceid = wo->neg_ifaceid && ao->neg_ifaceid;
516 
517     if (!wo->opt_local) {
518 	eui64_magic_nz(wo->ourid);
519     }
520 
521     *go = *wo;
522     eui64_zero(go->hisid);	/* last proposed interface identifier */
523 }
524 
525 
526 /*
527  * ipv6cp_cilen - Return length of our CI.
528  */
529 static int ipv6cp_cilen(fsm *f) {
530     ppp_pcb *pcb = f->pcb;
531     ipv6cp_options *go = &pcb->ipv6cp_gotoptions;
532 
533 #ifdef IPV6CP_COMP
534 #define LENCIVJ(neg)		(neg ? CILEN_COMPRESS : 0)
535 #endif /* IPV6CP_COMP */
536 #define LENCIIFACEID(neg)	(neg ? CILEN_IFACEID : 0)
537 
538     return (LENCIIFACEID(go->neg_ifaceid) +
539 #ifdef IPV6CP_COMP
540 	    LENCIVJ(go->neg_vj) +
541 #endif /* IPV6CP_COMP */
542 	    0);
543 }
544 
545 
546 /*
547  * ipv6cp_addci - Add our desired CIs to a packet.
548  */
549 static void ipv6cp_addci(fsm *f, u_char *ucp, int *lenp) {
550     ppp_pcb *pcb = f->pcb;
551     ipv6cp_options *go = &pcb->ipv6cp_gotoptions;
552     int len = *lenp;
553 
554 #ifdef IPV6CP_COMP
555 #define ADDCIVJ(opt, neg, val) \
556     if (neg) { \
557 	int vjlen = CILEN_COMPRESS; \
558 	if (len >= vjlen) { \
559 	    PUTCHAR(opt, ucp); \
560 	    PUTCHAR(vjlen, ucp); \
561 	    PUTSHORT(val, ucp); \
562 	    len -= vjlen; \
563 	} else \
564 	    neg = 0; \
565     }
566 #endif /* IPV6CP_COMP */
567 
568 #define ADDCIIFACEID(opt, neg, val1) \
569     if (neg) { \
570 	int idlen = CILEN_IFACEID; \
571 	if (len >= idlen) { \
572 	    PUTCHAR(opt, ucp); \
573 	    PUTCHAR(idlen, ucp); \
574 	    eui64_put(val1, ucp); \
575 	    len -= idlen; \
576 	} else \
577 	    neg = 0; \
578     }
579 
580     ADDCIIFACEID(CI_IFACEID, go->neg_ifaceid, go->ourid);
581 
582 #ifdef IPV6CP_COMP
583     ADDCIVJ(CI_COMPRESSTYPE, go->neg_vj, go->vj_protocol);
584 #endif /* IPV6CP_COMP */
585 
586     *lenp -= len;
587 }
588 
589 
590 /*
591  * ipv6cp_ackci - Ack our CIs.
592  *
593  * Returns:
594  *	0 - Ack was bad.
595  *	1 - Ack was good.
596  */
597 static int ipv6cp_ackci(fsm *f, u_char *p, int len) {
598     ppp_pcb *pcb = f->pcb;
599     ipv6cp_options *go = &pcb->ipv6cp_gotoptions;
600     u_short cilen, citype;
601 #ifdef IPV6CP_COMP
602     u_short cishort;
603 #endif /* IPV6CP_COMP */
604     eui64_t ifaceid;
605 
606     /*
607      * CIs must be in exactly the same order that we sent...
608      * Check packet length and CI length at each step.
609      * If we find any deviations, then this packet is bad.
610      */
611 
612 #ifdef IPV6CP_COMP
613 #define ACKCIVJ(opt, neg, val) \
614     if (neg) { \
615 	int vjlen = CILEN_COMPRESS; \
616 	if ((len -= vjlen) < 0) \
617 	    goto bad; \
618 	GETCHAR(citype, p); \
619 	GETCHAR(cilen, p); \
620 	if (cilen != vjlen || \
621 	    citype != opt)  \
622 	    goto bad; \
623 	GETSHORT(cishort, p); \
624 	if (cishort != val) \
625 	    goto bad; \
626     }
627 #endif /* IPV6CP_COMP */
628 
629 #define ACKCIIFACEID(opt, neg, val1) \
630     if (neg) { \
631 	int idlen = CILEN_IFACEID; \
632 	if ((len -= idlen) < 0) \
633 	    goto bad; \
634 	GETCHAR(citype, p); \
635 	GETCHAR(cilen, p); \
636 	if (cilen != idlen || \
637 	    citype != opt) \
638 	    goto bad; \
639 	eui64_get(ifaceid, p); \
640 	if (! eui64_equals(val1, ifaceid)) \
641 	    goto bad; \
642     }
643 
644     ACKCIIFACEID(CI_IFACEID, go->neg_ifaceid, go->ourid);
645 
646 #ifdef IPV6CP_COMP
647     ACKCIVJ(CI_COMPRESSTYPE, go->neg_vj, go->vj_protocol);
648 #endif /* IPV6CP_COMP */
649 
650     /*
651      * If there are any remaining CIs, then this packet is bad.
652      */
653     if (len != 0)
654 	goto bad;
655     return (1);
656 
657 bad:
658     IPV6CPDEBUG(("ipv6cp_ackci: received bad Ack!"));
659     return (0);
660 }
661 
662 /*
663  * ipv6cp_nakci - Peer has sent a NAK for some of our CIs.
664  * This should not modify any state if the Nak is bad
665  * or if IPV6CP is in the OPENED state.
666  *
667  * Returns:
668  *	0 - Nak was bad.
669  *	1 - Nak was good.
670  */
671 static int ipv6cp_nakci(fsm *f, u_char *p, int len, int treat_as_reject) {
672     ppp_pcb *pcb = f->pcb;
673     ipv6cp_options *go = &pcb->ipv6cp_gotoptions;
674     u_char citype, cilen, *next;
675 #ifdef IPV6CP_COMP
676     u_short cishort;
677 #endif /* IPV6CP_COMP */
678     eui64_t ifaceid;
679     ipv6cp_options no;		/* options we've seen Naks for */
680     ipv6cp_options try_;	/* options to request next time */
681 
682     BZERO(&no, sizeof(no));
683     try_ = *go;
684 
685     /*
686      * Any Nak'd CIs must be in exactly the same order that we sent.
687      * Check packet length and CI length at each step.
688      * If we find any deviations, then this packet is bad.
689      */
690 #define NAKCIIFACEID(opt, neg, code) \
691     if (go->neg && \
692 	len >= (cilen = CILEN_IFACEID) && \
693 	p[1] == cilen && \
694 	p[0] == opt) { \
695 	len -= cilen; \
696 	INCPTR(2, p); \
697 	eui64_get(ifaceid, p); \
698 	no.neg = 1; \
699 	code \
700     }
701 
702 #ifdef IPV6CP_COMP
703 #define NAKCIVJ(opt, neg, code) \
704     if (go->neg && \
705 	((cilen = p[1]) == CILEN_COMPRESS) && \
706 	len >= cilen && \
707 	p[0] == opt) { \
708 	len -= cilen; \
709 	INCPTR(2, p); \
710 	GETSHORT(cishort, p); \
711 	no.neg = 1; \
712         code \
713     }
714 #endif /* IPV6CP_COMP */
715 
716     /*
717      * Accept the peer's idea of {our,his} interface identifier, if different
718      * from our idea, only if the accept_{local,remote} flag is set.
719      */
720     NAKCIIFACEID(CI_IFACEID, neg_ifaceid,
721 		 if (treat_as_reject) {
722 		     try_.neg_ifaceid = 0;
723 		 } else if (go->accept_local) {
724 		     while (eui64_iszero(ifaceid) ||
725 			    eui64_equals(ifaceid, go->hisid)) /* bad luck */
726 			 eui64_magic(ifaceid);
727 		     try_.ourid = ifaceid;
728 		     IPV6CPDEBUG(("local LL address %s", llv6_ntoa(ifaceid)));
729 		 }
730 		 );
731 
732 #ifdef IPV6CP_COMP
733     NAKCIVJ(CI_COMPRESSTYPE, neg_vj,
734 	    {
735 		if (cishort == IPV6CP_COMP && !treat_as_reject) {
736 		    try_.vj_protocol = cishort;
737 		} else {
738 		    try_.neg_vj = 0;
739 		}
740 	    }
741 	    );
742 #endif /* IPV6CP_COMP */
743 
744     /*
745      * There may be remaining CIs, if the peer is requesting negotiation
746      * on an option that we didn't include in our request packet.
747      * If they want to negotiate about interface identifier, we comply.
748      * If they want us to ask for compression, we refuse.
749      */
750     while (len >= CILEN_VOID) {
751 	GETCHAR(citype, p);
752 	GETCHAR(cilen, p);
753 	if ( cilen < CILEN_VOID || (len -= cilen) < 0 )
754 	    goto bad;
755 	next = p + cilen - 2;
756 
757 	switch (citype) {
758 #ifdef IPV6CP_COMP
759 	case CI_COMPRESSTYPE:
760 	    if (go->neg_vj || no.neg_vj ||
761 		(cilen != CILEN_COMPRESS))
762 		goto bad;
763 	    no.neg_vj = 1;
764 	    break;
765 #endif /* IPV6CP_COMP */
766 	case CI_IFACEID:
767 	    if (go->neg_ifaceid || no.neg_ifaceid || cilen != CILEN_IFACEID)
768 		goto bad;
769 	    try_.neg_ifaceid = 1;
770 	    eui64_get(ifaceid, p);
771 	    if (go->accept_local) {
772 		while (eui64_iszero(ifaceid) ||
773 		       eui64_equals(ifaceid, go->hisid)) /* bad luck */
774 		    eui64_magic(ifaceid);
775 		try_.ourid = ifaceid;
776 	    }
777 	    no.neg_ifaceid = 1;
778 	    break;
779 	default:
780 	    break;
781 	}
782 	p = next;
783     }
784 
785     /* If there is still anything left, this packet is bad. */
786     if (len != 0)
787 	goto bad;
788 
789     /*
790      * OK, the Nak is good.  Now we can update state.
791      */
792     if (f->state != PPP_FSM_OPENED)
793 	*go = try_;
794 
795     return 1;
796 
797 bad:
798     IPV6CPDEBUG(("ipv6cp_nakci: received bad Nak!"));
799     return 0;
800 }
801 
802 
803 /*
804  * ipv6cp_rejci - Reject some of our CIs.
805  */
806 static int ipv6cp_rejci(fsm *f, u_char *p, int len) {
807     ppp_pcb *pcb = f->pcb;
808     ipv6cp_options *go = &pcb->ipv6cp_gotoptions;
809     u_char cilen;
810 #ifdef IPV6CP_COMP
811     u_short cishort;
812 #endif /* IPV6CP_COMP */
813     eui64_t ifaceid;
814     ipv6cp_options try_;		/* options to request next time */
815 
816     try_ = *go;
817     /*
818      * Any Rejected CIs must be in exactly the same order that we sent.
819      * Check packet length and CI length at each step.
820      * If we find any deviations, then this packet is bad.
821      */
822 #define REJCIIFACEID(opt, neg, val1) \
823     if (go->neg && \
824 	len >= (cilen = CILEN_IFACEID) && \
825 	p[1] == cilen && \
826 	p[0] == opt) { \
827 	len -= cilen; \
828 	INCPTR(2, p); \
829 	eui64_get(ifaceid, p); \
830 	/* Check rejected value. */ \
831 	if (! eui64_equals(ifaceid, val1)) \
832 	    goto bad; \
833 	try_.neg = 0; \
834     }
835 
836 #ifdef IPV6CP_COMP
837 #define REJCIVJ(opt, neg, val) \
838     if (go->neg && \
839 	p[1] == CILEN_COMPRESS && \
840 	len >= p[1] && \
841 	p[0] == opt) { \
842 	len -= p[1]; \
843 	INCPTR(2, p); \
844 	GETSHORT(cishort, p); \
845 	/* Check rejected value. */  \
846 	if (cishort != val) \
847 	    goto bad; \
848 	try_.neg = 0; \
849      }
850 #endif /* IPV6CP_COMP */
851 
852     REJCIIFACEID(CI_IFACEID, neg_ifaceid, go->ourid);
853 
854 #ifdef IPV6CP_COMP
855     REJCIVJ(CI_COMPRESSTYPE, neg_vj, go->vj_protocol);
856 #endif /* IPV6CP_COMP */
857 
858     /*
859      * If there are any remaining CIs, then this packet is bad.
860      */
861     if (len != 0)
862 	goto bad;
863     /*
864      * Now we can update state.
865      */
866     if (f->state != PPP_FSM_OPENED)
867 	*go = try_;
868     return 1;
869 
870 bad:
871     IPV6CPDEBUG(("ipv6cp_rejci: received bad Reject!"));
872     return 0;
873 }
874 
875 
876 /*
877  * ipv6cp_reqci - Check the peer's requested CIs and send appropriate response.
878  *
879  * Returns: CONFACK, CONFNAK or CONFREJ and input packet modified
880  * appropriately.  If reject_if_disagree is non-zero, doesn't return
881  * CONFNAK; returns CONFREJ if it can't return CONFACK.
882  *
883  * inp = Requested CIs
884  * len = Length of requested CIs
885  *
886  */
887 static int ipv6cp_reqci(fsm *f, u_char *inp, int *len, int reject_if_disagree) {
888     ppp_pcb *pcb = f->pcb;
889     ipv6cp_options *wo = &pcb->ipv6cp_wantoptions;
890     ipv6cp_options *ho = &pcb->ipv6cp_hisoptions;
891     ipv6cp_options *ao = &pcb->ipv6cp_allowoptions;
892     ipv6cp_options *go = &pcb->ipv6cp_gotoptions;
893     u_char *cip, *next;		/* Pointer to current and next CIs */
894     u_short cilen, citype;	/* Parsed len, type */
895 #ifdef IPV6CP_COMP
896     u_short cishort;		/* Parsed short value */
897 #endif /* IPV6CP_COMP */
898     eui64_t ifaceid;		/* Parsed interface identifier */
899     int rc = CONFACK;		/* Final packet return code */
900     int orc;			/* Individual option return code */
901     u_char *p;			/* Pointer to next char to parse */
902     u_char *ucp = inp;		/* Pointer to current output char */
903     int l = *len;		/* Length left */
904 
905     /*
906      * Reset all his options.
907      */
908     BZERO(ho, sizeof(*ho));
909 
910     /*
911      * Process all his options.
912      */
913     next = inp;
914     while (l) {
915 	orc = CONFACK;			/* Assume success */
916 	cip = p = next;			/* Remember begining of CI */
917 	if (l < 2 ||			/* Not enough data for CI header or */
918 	    p[1] < 2 ||			/*  CI length too small or */
919 	    p[1] > l) {			/*  CI length too big? */
920 	    IPV6CPDEBUG(("ipv6cp_reqci: bad CI length!"));
921 	    orc = CONFREJ;		/* Reject bad CI */
922 	    cilen = l;			/* Reject till end of packet */
923 	    l = 0;			/* Don't loop again */
924 	    goto endswitch;
925 	}
926 	GETCHAR(citype, p);		/* Parse CI type */
927 	GETCHAR(cilen, p);		/* Parse CI length */
928 	l -= cilen;			/* Adjust remaining length */
929 	next += cilen;			/* Step to next CI */
930 
931 	switch (citype) {		/* Check CI type */
932 	case CI_IFACEID:
933 	    IPV6CPDEBUG(("ipv6cp: received interface identifier "));
934 
935 	    if (!ao->neg_ifaceid ||
936 		cilen != CILEN_IFACEID) {	/* Check CI length */
937 		orc = CONFREJ;		/* Reject CI */
938 		break;
939 	    }
940 
941 	    /*
942 	     * If he has no interface identifier, or if we both have same
943 	     * identifier then NAK it with new idea.
944 	     * In particular, if we don't know his identifier, but he does,
945 	     * then accept it.
946 	     */
947 	    eui64_get(ifaceid, p);
948 	    IPV6CPDEBUG(("(%s)", llv6_ntoa(ifaceid)));
949 	    if (eui64_iszero(ifaceid) && eui64_iszero(go->ourid)) {
950 		orc = CONFREJ;		/* Reject CI */
951 		break;
952 	    }
953 	    if (!eui64_iszero(wo->hisid) &&
954 		!eui64_equals(ifaceid, wo->hisid) &&
955 		eui64_iszero(go->hisid)) {
956 
957 		orc = CONFNAK;
958 		ifaceid = wo->hisid;
959 		go->hisid = ifaceid;
960 		DECPTR(sizeof(ifaceid), p);
961 		eui64_put(ifaceid, p);
962 	    } else
963 	    if (eui64_iszero(ifaceid) || eui64_equals(ifaceid, go->ourid)) {
964 		orc = CONFNAK;
965 		if (eui64_iszero(go->hisid))	/* first time, try option */
966 		    ifaceid = wo->hisid;
967 		while (eui64_iszero(ifaceid) ||
968 		       eui64_equals(ifaceid, go->ourid)) /* bad luck */
969 		    eui64_magic(ifaceid);
970 		go->hisid = ifaceid;
971 		DECPTR(sizeof(ifaceid), p);
972 		eui64_put(ifaceid, p);
973 	    }
974 
975 	    ho->neg_ifaceid = 1;
976 	    ho->hisid = ifaceid;
977 	    break;
978 
979 #ifdef IPV6CP_COMP
980 	case CI_COMPRESSTYPE:
981 	    IPV6CPDEBUG(("ipv6cp: received COMPRESSTYPE "));
982 	    if (!ao->neg_vj ||
983 		(cilen != CILEN_COMPRESS)) {
984 		orc = CONFREJ;
985 		break;
986 	    }
987 	    GETSHORT(cishort, p);
988 	    IPV6CPDEBUG(("(%d)", cishort));
989 
990 	    if (!(cishort == IPV6CP_COMP)) {
991 		orc = CONFREJ;
992 		break;
993 	    }
994 
995 	    ho->neg_vj = 1;
996 	    ho->vj_protocol = cishort;
997 	    break;
998 #endif /* IPV6CP_COMP */
999 
1000 	default:
1001 	    orc = CONFREJ;
1002 	    break;
1003 	}
1004 
1005 endswitch:
1006 	IPV6CPDEBUG((" (%s)\n", CODENAME(orc)));
1007 
1008 	if (orc == CONFACK &&		/* Good CI */
1009 	    rc != CONFACK)		/*  but prior CI wasnt? */
1010 	    continue;			/* Don't send this one */
1011 
1012 	if (orc == CONFNAK) {		/* Nak this CI? */
1013 	    if (reject_if_disagree)	/* Getting fed up with sending NAKs? */
1014 		orc = CONFREJ;		/* Get tough if so */
1015 	    else {
1016 		if (rc == CONFREJ)	/* Rejecting prior CI? */
1017 		    continue;		/* Don't send this one */
1018 		if (rc == CONFACK) {	/* Ack'd all prior CIs? */
1019 		    rc = CONFNAK;	/* Not anymore... */
1020 		    ucp = inp;		/* Backup */
1021 		}
1022 	    }
1023 	}
1024 
1025 	if (orc == CONFREJ &&		/* Reject this CI */
1026 	    rc != CONFREJ) {		/*  but no prior ones? */
1027 	    rc = CONFREJ;
1028 	    ucp = inp;			/* Backup */
1029 	}
1030 
1031 	/* Need to move CI? */
1032 	if (ucp != cip)
1033 	    MEMCPY(ucp, cip, cilen);	/* Move it */
1034 
1035 	/* Update output pointer */
1036 	INCPTR(cilen, ucp);
1037     }
1038 
1039     /*
1040      * If we aren't rejecting this packet, and we want to negotiate
1041      * their identifier and they didn't send their identifier, then we
1042      * send a NAK with a CI_IFACEID option appended.  We assume the
1043      * input buffer is long enough that we can append the extra
1044      * option safely.
1045      */
1046     if (rc != CONFREJ && !ho->neg_ifaceid &&
1047 	wo->req_ifaceid && !reject_if_disagree) {
1048 	if (rc == CONFACK) {
1049 	    rc = CONFNAK;
1050 	    ucp = inp;				/* reset pointer */
1051 	    wo->req_ifaceid = 0;		/* don't ask again */
1052 	}
1053 	PUTCHAR(CI_IFACEID, ucp);
1054 	PUTCHAR(CILEN_IFACEID, ucp);
1055 	eui64_put(wo->hisid, ucp);
1056     }
1057 
1058     *len = ucp - inp;			/* Compute output length */
1059     IPV6CPDEBUG(("ipv6cp: returning Configure-%s", CODENAME(rc)));
1060     return (rc);			/* Return final code */
1061 }
1062 
1063 #if PPP_OPTIONS
1064 /*
1065  * ipv6_check_options - check that any IP-related options are OK,
1066  * and assign appropriate defaults.
1067  */
1068 static void ipv6_check_options() {
1069     ipv6cp_options *wo = &ipv6cp_wantoptions[0];
1070 
1071     if (!ipv6cp_protent.enabled_flag)
1072 	return;
1073 
1074     /*
1075      * Persistent link-local id is only used when user has not explicitly
1076      * configure/hard-code the id
1077      */
1078     if ((wo->use_persistent) && (!wo->opt_local) && (!wo->opt_remote)) {
1079 
1080 	/*
1081 	 * On systems where there are no Ethernet interfaces used, there
1082 	 * may be other ways to obtain a persistent id. Right now, it
1083 	 * will fall back to using magic [see eui64_magic] below when
1084 	 * an EUI-48 from MAC address can't be obtained. Other possibilities
1085 	 * include obtaining EEPROM serial numbers, or some other unique
1086 	 * yet persistent number. On Sparc platforms, this is possible,
1087 	 * but too bad there's no standards yet for x86 machines.
1088 	 */
1089 	if (ether_to_eui64(&wo->ourid)) {
1090 	    wo->opt_local = 1;
1091 	}
1092     }
1093 
1094     if (!wo->opt_local) {	/* init interface identifier */
1095 	if (wo->use_ip && eui64_iszero(wo->ourid)) {
1096 	    eui64_setlo32(wo->ourid, lwip_ntohl(ipcp_wantoptions[0].ouraddr));
1097 	    if (!eui64_iszero(wo->ourid))
1098 		wo->opt_local = 1;
1099 	}
1100 
1101 	while (eui64_iszero(wo->ourid))
1102 	    eui64_magic(wo->ourid);
1103     }
1104 
1105     if (!wo->opt_remote) {
1106 	if (wo->use_ip && eui64_iszero(wo->hisid)) {
1107 	    eui64_setlo32(wo->hisid, lwip_ntohl(ipcp_wantoptions[0].hisaddr));
1108 	    if (!eui64_iszero(wo->hisid))
1109 		wo->opt_remote = 1;
1110 	}
1111     }
1112 
1113     if (demand && (eui64_iszero(wo->ourid) || eui64_iszero(wo->hisid))) {
1114 	option_error("local/remote LL address required for demand-dialling\n");
1115 	exit(1);
1116     }
1117 }
1118 #endif /* PPP_OPTIONS */
1119 
1120 #if DEMAND_SUPPORT
1121 /*
1122  * ipv6_demand_conf - configure the interface as though
1123  * IPV6CP were up, for use with dial-on-demand.
1124  */
1125 static int ipv6_demand_conf(int u) {
1126     ipv6cp_options *wo = &ipv6cp_wantoptions[u];
1127 
1128     if (!sif6up(u))
1129 	return 0;
1130 
1131     if (!sif6addr(u, wo->ourid, wo->hisid))
1132 	return 0;
1133 
1134     if (!sifnpmode(u, PPP_IPV6, NPMODE_QUEUE))
1135 	return 0;
1136 
1137     ppp_notice("ipv6_demand_conf");
1138     ppp_notice("local  LL address %s", llv6_ntoa(wo->ourid));
1139     ppp_notice("remote LL address %s", llv6_ntoa(wo->hisid));
1140 
1141     return 1;
1142 }
1143 #endif /* DEMAND_SUPPORT */
1144 
1145 
1146 /*
1147  * ipv6cp_up - IPV6CP has come UP.
1148  *
1149  * Configure the IPv6 network interface appropriately and bring it up.
1150  */
1151 static void ipv6cp_up(fsm *f) {
1152     ppp_pcb *pcb = f->pcb;
1153     ipv6cp_options *wo = &pcb->ipv6cp_wantoptions;
1154     ipv6cp_options *ho = &pcb->ipv6cp_hisoptions;
1155     ipv6cp_options *go = &pcb->ipv6cp_gotoptions;
1156 
1157     IPV6CPDEBUG(("ipv6cp: up"));
1158 
1159     /*
1160      * We must have a non-zero LL address for both ends of the link.
1161      */
1162     if (!ho->neg_ifaceid)
1163 	ho->hisid = wo->hisid;
1164 
1165 #if 0 /* UNUSED */
1166     if(!no_ifaceid_neg) {
1167 #endif /* UNUSED */
1168 	if (eui64_iszero(ho->hisid)) {
1169 	    ppp_error("Could not determine remote LL address");
1170 	    ipv6cp_close(f->pcb, "Could not determine remote LL address");
1171 	    return;
1172 	}
1173 	if (eui64_iszero(go->ourid)) {
1174 	    ppp_error("Could not determine local LL address");
1175 	    ipv6cp_close(f->pcb, "Could not determine local LL address");
1176 	    return;
1177 	}
1178 	if (eui64_equals(go->ourid, ho->hisid)) {
1179 	    ppp_error("local and remote LL addresses are equal");
1180 	    ipv6cp_close(f->pcb, "local and remote LL addresses are equal");
1181 	    return;
1182 	}
1183 #if 0 /* UNUSED */
1184     }
1185 #endif /* UNUSED */
1186 #if 0 /* UNUSED */
1187     script_setenv("LLLOCAL", llv6_ntoa(go->ourid), 0);
1188     script_setenv("LLREMOTE", llv6_ntoa(ho->hisid), 0);
1189 #endif /* UNUSED */
1190 
1191 #ifdef IPV6CP_COMP
1192     /* set tcp compression */
1193     sif6comp(f->unit, ho->neg_vj);
1194 #endif
1195 
1196 #if DEMAND_SUPPORT
1197     /*
1198      * If we are doing dial-on-demand, the interface is already
1199      * configured, so we put out any saved-up packets, then set the
1200      * interface to pass IPv6 packets.
1201      */
1202     if (demand) {
1203 	if (! eui64_equals(go->ourid, wo->ourid) ||
1204 	    ! eui64_equals(ho->hisid, wo->hisid)) {
1205 	    if (! eui64_equals(go->ourid, wo->ourid))
1206 		warn("Local LL address changed to %s",
1207 		     llv6_ntoa(go->ourid));
1208 	    if (! eui64_equals(ho->hisid, wo->hisid))
1209 		warn("Remote LL address changed to %s",
1210 		     llv6_ntoa(ho->hisid));
1211 	    ipv6cp_clear_addrs(f->pcb, go->ourid, ho->hisid);
1212 
1213 	    /* Set the interface to the new addresses */
1214 	    if (!sif6addr(f->pcb, go->ourid, ho->hisid)) {
1215 		if (debug)
1216 		    warn("sif6addr failed");
1217 		ipv6cp_close(f->unit, "Interface configuration failed");
1218 		return;
1219 	    }
1220 
1221 	}
1222 	demand_rexmit(PPP_IPV6);
1223 	sifnpmode(f->unit, PPP_IPV6, NPMODE_PASS);
1224 
1225     } else
1226 #endif /* DEMAND_SUPPORT */
1227     {
1228 	/*
1229 	 * Set LL addresses
1230 	 */
1231 	if (!sif6addr(f->pcb, go->ourid, ho->hisid)) {
1232 	    PPPDEBUG(LOG_DEBUG, ("sif6addr failed"));
1233 	    ipv6cp_close(f->pcb, "Interface configuration failed");
1234 	    return;
1235 	}
1236 
1237 	/* bring the interface up for IPv6 */
1238 	if (!sif6up(f->pcb)) {
1239 	    PPPDEBUG(LOG_DEBUG, ("sif6up failed (IPV6)"));
1240 	    ipv6cp_close(f->pcb, "Interface configuration failed");
1241 	    return;
1242 	}
1243 #if DEMAND_SUPPORT
1244 	sifnpmode(f->pcb, PPP_IPV6, NPMODE_PASS);
1245 #endif /* DEMAND_SUPPORT */
1246 
1247 	ppp_notice("local  LL address %s", llv6_ntoa(go->ourid));
1248 	ppp_notice("remote LL address %s", llv6_ntoa(ho->hisid));
1249     }
1250 
1251     np_up(f->pcb, PPP_IPV6);
1252     pcb->ipv6cp_is_up = 1;
1253 
1254 #if 0 /* UNUSED */
1255     /*
1256      * Execute the ipv6-up script, like this:
1257      *	/etc/ppp/ipv6-up interface tty speed local-LL remote-LL
1258      */
1259     if (ipv6cp_script_state == s_down && ipv6cp_script_pid == 0) {
1260 	ipv6cp_script_state = s_up;
1261 	ipv6cp_script(_PATH_IPV6UP);
1262     }
1263 #endif /* UNUSED */
1264 }
1265 
1266 
1267 /*
1268  * ipv6cp_down - IPV6CP has gone DOWN.
1269  *
1270  * Take the IPv6 network interface down, clear its addresses
1271  * and delete routes through it.
1272  */
1273 static void ipv6cp_down(fsm *f) {
1274     ppp_pcb *pcb = f->pcb;
1275     ipv6cp_options *go = &pcb->ipv6cp_gotoptions;
1276     ipv6cp_options *ho = &pcb->ipv6cp_hisoptions;
1277 
1278     IPV6CPDEBUG(("ipv6cp: down"));
1279 #if PPP_STATS_SUPPORT
1280     update_link_stats(f->unit);
1281 #endif /* PPP_STATS_SUPPORT */
1282     if (pcb->ipv6cp_is_up) {
1283 	pcb->ipv6cp_is_up = 0;
1284 	np_down(f->pcb, PPP_IPV6);
1285     }
1286 #ifdef IPV6CP_COMP
1287     sif6comp(f->unit, 0);
1288 #endif
1289 
1290 #if DEMAND_SUPPORT
1291     /*
1292      * If we are doing dial-on-demand, set the interface
1293      * to queue up outgoing packets (for now).
1294      */
1295     if (demand) {
1296 	sifnpmode(f->pcb, PPP_IPV6, NPMODE_QUEUE);
1297     } else
1298 #endif /* DEMAND_SUPPORT */
1299     {
1300 #if DEMAND_SUPPORT
1301 	sifnpmode(f->pcb, PPP_IPV6, NPMODE_DROP);
1302 #endif /* DEMAND_SUPPORT */
1303 	ipv6cp_clear_addrs(f->pcb,
1304 			   go->ourid,
1305 			   ho->hisid);
1306 	sif6down(f->pcb);
1307     }
1308 
1309 #if 0 /* UNUSED */
1310     /* Execute the ipv6-down script */
1311     if (ipv6cp_script_state == s_up && ipv6cp_script_pid == 0) {
1312 	ipv6cp_script_state = s_down;
1313 	ipv6cp_script(_PATH_IPV6DOWN);
1314     }
1315 #endif /* UNUSED */
1316 }
1317 
1318 
1319 /*
1320  * ipv6cp_clear_addrs() - clear the interface addresses, routes,
1321  * proxy neighbour discovery entries, etc.
1322  */
1323 static void ipv6cp_clear_addrs(ppp_pcb *pcb, eui64_t ourid, eui64_t hisid) {
1324     cif6addr(pcb, ourid, hisid);
1325 }
1326 
1327 
1328 /*
1329  * ipv6cp_finished - possibly shut down the lower layers.
1330  */
1331 static void ipv6cp_finished(fsm *f) {
1332     np_finished(f->pcb, PPP_IPV6);
1333 }
1334 
1335 
1336 #if 0 /* UNUSED */
1337 /*
1338  * ipv6cp_script_done - called when the ipv6-up or ipv6-down script
1339  * has finished.
1340  */
1341 static void
1342 ipv6cp_script_done(arg)
1343     void *arg;
1344 {
1345     ipv6cp_script_pid = 0;
1346     switch (ipv6cp_script_state) {
1347     case s_up:
1348 	if (ipv6cp_fsm[0].state != PPP_FSM_OPENED) {
1349 	    ipv6cp_script_state = s_down;
1350 	    ipv6cp_script(_PATH_IPV6DOWN);
1351 	}
1352 	break;
1353     case s_down:
1354 	if (ipv6cp_fsm[0].state == PPP_FSM_OPENED) {
1355 	    ipv6cp_script_state = s_up;
1356 	    ipv6cp_script(_PATH_IPV6UP);
1357 	}
1358 	break;
1359     }
1360 }
1361 
1362 
1363 /*
1364  * ipv6cp_script - Execute a script with arguments
1365  * interface-name tty-name speed local-LL remote-LL.
1366  */
1367 static void
1368 ipv6cp_script(script)
1369     char *script;
1370 {
1371     char strspeed[32], strlocal[32], strremote[32];
1372     char *argv[8];
1373 
1374     sprintf(strspeed, "%d", baud_rate);
1375     strcpy(strlocal, llv6_ntoa(ipv6cp_gotoptions[0].ourid));
1376     strcpy(strremote, llv6_ntoa(ipv6cp_hisoptions[0].hisid));
1377 
1378     argv[0] = script;
1379     argv[1] = ifname;
1380     argv[2] = devnam;
1381     argv[3] = strspeed;
1382     argv[4] = strlocal;
1383     argv[5] = strremote;
1384     argv[6] = ipparam;
1385     argv[7] = NULL;
1386 
1387     ipv6cp_script_pid = run_program(script, argv, 0, ipv6cp_script_done,
1388 				    NULL, 0);
1389 }
1390 #endif /* UNUSED */
1391 
1392 #if PRINTPKT_SUPPORT
1393 /*
1394  * ipv6cp_printpkt - print the contents of an IPV6CP packet.
1395  */
1396 static const char* const ipv6cp_codenames[] = {
1397     "ConfReq", "ConfAck", "ConfNak", "ConfRej",
1398     "TermReq", "TermAck", "CodeRej"
1399 };
1400 
1401 static int ipv6cp_printpkt(const u_char *p, int plen,
1402 		void (*printer)(void *, const char *, ...), void *arg) {
1403     int code, id, len, olen;
1404     const u_char *pstart, *optend;
1405 #ifdef IPV6CP_COMP
1406     u_short cishort;
1407 #endif /* IPV6CP_COMP */
1408     eui64_t ifaceid;
1409 
1410     if (plen < HEADERLEN)
1411 	return 0;
1412     pstart = p;
1413     GETCHAR(code, p);
1414     GETCHAR(id, p);
1415     GETSHORT(len, p);
1416     if (len < HEADERLEN || len > plen)
1417 	return 0;
1418 
1419     if (code >= 1 && code <= (int)LWIP_ARRAYSIZE(ipv6cp_codenames))
1420 	printer(arg, " %s", ipv6cp_codenames[code-1]);
1421     else
1422 	printer(arg, " code=0x%x", code);
1423     printer(arg, " id=0x%x", id);
1424     len -= HEADERLEN;
1425     switch (code) {
1426     case CONFREQ:
1427     case CONFACK:
1428     case CONFNAK:
1429     case CONFREJ:
1430 	/* print option list */
1431 	while (len >= 2) {
1432 	    GETCHAR(code, p);
1433 	    GETCHAR(olen, p);
1434 	    p -= 2;
1435 	    if (olen < 2 || olen > len) {
1436 		break;
1437 	    }
1438 	    printer(arg, " <");
1439 	    len -= olen;
1440 	    optend = p + olen;
1441 	    switch (code) {
1442 #ifdef IPV6CP_COMP
1443 	    case CI_COMPRESSTYPE:
1444 		if (olen >= CILEN_COMPRESS) {
1445 		    p += 2;
1446 		    GETSHORT(cishort, p);
1447 		    printer(arg, "compress ");
1448 		    printer(arg, "0x%x", cishort);
1449 		}
1450 		break;
1451 #endif /* IPV6CP_COMP */
1452 	    case CI_IFACEID:
1453 		if (olen == CILEN_IFACEID) {
1454 		    p += 2;
1455 		    eui64_get(ifaceid, p);
1456 		    printer(arg, "addr %s", llv6_ntoa(ifaceid));
1457 		}
1458 		break;
1459 	    default:
1460 		break;
1461 	    }
1462 	    while (p < optend) {
1463 		GETCHAR(code, p);
1464 		printer(arg, " %.2x", code);
1465 	    }
1466 	    printer(arg, ">");
1467 	}
1468 	break;
1469 
1470     case TERMACK:
1471     case TERMREQ:
1472 	if (len > 0 && *p >= ' ' && *p < 0x7f) {
1473 	    printer(arg, " ");
1474 	    ppp_print_string(p, len, printer, arg);
1475 	    p += len;
1476 	    len = 0;
1477 	}
1478 	break;
1479     default:
1480 	break;
1481     }
1482 
1483     /* print the rest of the bytes in the packet */
1484     for (; len > 0; --len) {
1485 	GETCHAR(code, p);
1486 	printer(arg, " %.2x", code);
1487     }
1488 
1489     return p - pstart;
1490 }
1491 #endif /* PRINTPKT_SUPPORT */
1492 
1493 #if DEMAND_SUPPORT
1494 /*
1495  * ipv6_active_pkt - see if this IP packet is worth bringing the link up for.
1496  * We don't bring the link up for IP fragments or for TCP FIN packets
1497  * with no data.
1498  */
1499 #define IP6_HDRLEN	40	/* bytes */
1500 #define IP6_NHDR_FRAG	44	/* fragment IPv6 header */
1501 #define TCP_HDRLEN	20
1502 #define TH_FIN		0x01
1503 
1504 /*
1505  * We use these macros because the IP header may be at an odd address,
1506  * and some compilers might use word loads to get th_off or ip_hl.
1507  */
1508 
1509 #define get_ip6nh(x)	(((unsigned char *)(x))[6])
1510 #define get_tcpoff(x)	(((unsigned char *)(x))[12] >> 4)
1511 #define get_tcpflags(x)	(((unsigned char *)(x))[13])
1512 
1513 static int ipv6_active_pkt(u_char *pkt, int len) {
1514     u_char *tcp;
1515 
1516     len -= PPP_HDRLEN;
1517     pkt += PPP_HDRLEN;
1518     if (len < IP6_HDRLEN)
1519 	return 0;
1520     if (get_ip6nh(pkt) == IP6_NHDR_FRAG)
1521 	return 0;
1522     if (get_ip6nh(pkt) != IPPROTO_TCP)
1523 	return 1;
1524     if (len < IP6_HDRLEN + TCP_HDRLEN)
1525 	return 0;
1526     tcp = pkt + IP6_HDRLEN;
1527     if ((get_tcpflags(tcp) & TH_FIN) != 0 && len == IP6_HDRLEN + get_tcpoff(tcp) * 4)
1528 	return 0;
1529     return 1;
1530 }
1531 #endif /* DEMAND_SUPPORT */
1532 
1533 #endif /* PPP_SUPPORT && PPP_IPV6_SUPPORT */
1534