1 /*
2 * ipcp.c - PPP IP Control Protocol.
3 *
4 * Copyright (c) 1984-2000 Carnegie Mellon University. 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 "Carnegie Mellon University" must not be used to
19 * endorse or promote products derived from this software without
20 * prior written permission. For permission or any legal
21 * details, please contact
22 * Office of Technology Transfer
23 * Carnegie Mellon University
24 * 5000 Forbes Avenue
25 * Pittsburgh, PA 15213-3890
26 * (412) 268-4387, fax: (412) 268-7395
27 * tech-transfer@andrew.cmu.edu
28 *
29 * 4. Redistributions of any form whatsoever must retain the following
30 * acknowledgment:
31 * "This product includes software developed by Computing Services
32 * at Carnegie Mellon University (http://www.cmu.edu/computing/)."
33 *
34 * CARNEGIE MELLON UNIVERSITY DISCLAIMS ALL WARRANTIES WITH REGARD TO
35 * THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
36 * AND FITNESS, IN NO EVENT SHALL CARNEGIE MELLON UNIVERSITY BE LIABLE
37 * FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
38 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN
39 * AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING
40 * OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
41 */
42
43 #define RCSID "$Id: ipcp.c,v 1.73 2008/05/26 08:33:22 paulus Exp $"
44
45 /*
46 * TODO:
47 */
48
49 #include <stdio.h>
50 #include <string.h>
51 #include <stdlib.h>
52 #include <netdb.h>
53 #include <sys/param.h>
54 #include <sys/types.h>
55 #include <sys/socket.h>
56 #include <netinet/in.h>
57 #include <arpa/inet.h>
58
59 #include "pppd.h"
60 #include "fsm.h"
61 #include "ipcp.h"
62 #include "pathnames.h"
63
64 static const char rcsid[] = RCSID;
65
66 /* global vars */
67 ipcp_options ipcp_wantoptions[NUM_PPP]; /* Options that we want to request */
68 ipcp_options ipcp_gotoptions[NUM_PPP]; /* Options that peer ack'd */
69 ipcp_options ipcp_allowoptions[NUM_PPP]; /* Options we allow peer to request */
70 ipcp_options ipcp_hisoptions[NUM_PPP]; /* Options that we ack'd */
71
72 u_int32_t netmask = 0; /* IP netmask to set on interface */
73
74 bool disable_defaultip = 0; /* Don't use hostname for default IP adrs */
75 bool noremoteip = 0; /* Let him have no IP address */
76
77 /* Hook for a plugin to know when IP protocol has come up */
78 void (*ip_up_hook) __P((void)) = NULL;
79
80 /* Hook for a plugin to know when IP protocol has come down */
81 void (*ip_down_hook) __P((void)) = NULL;
82
83 /* Hook for a plugin to choose the remote IP address */
84 void (*ip_choose_hook) __P((u_int32_t *)) = NULL;
85
86 /* Notifiers for when IPCP goes up and down */
87 struct notifier *ip_up_notifier = NULL;
88 struct notifier *ip_down_notifier = NULL;
89
90 /* local vars */
91 static int default_route_set[NUM_PPP]; /* Have set up a default route */
92 static int proxy_arp_set[NUM_PPP]; /* Have created proxy arp entry */
93 static bool usepeerdns; /* Ask peer for DNS addrs */
94 static int ipcp_is_up; /* have called np_up() */
95 static int ipcp_is_open; /* haven't called np_finished() */
96 static bool ask_for_local; /* request our address from peer */
97 static char vj_value[8]; /* string form of vj option value */
98 static char netmask_str[20]; /* string form of netmask value */
99
100 /*
101 * Callbacks for fsm code. (CI = Configuration Information)
102 */
103 static void ipcp_resetci __P((fsm *)); /* Reset our CI */
104 static int ipcp_cilen __P((fsm *)); /* Return length of our CI */
105 static void ipcp_addci __P((fsm *, u_char *, int *)); /* Add our CI */
106 static int ipcp_ackci __P((fsm *, u_char *, int)); /* Peer ack'd our CI */
107 static int ipcp_nakci __P((fsm *, u_char *, int, int));/* Peer nak'd our CI */
108 static int ipcp_rejci __P((fsm *, u_char *, int)); /* Peer rej'd our CI */
109 static int ipcp_reqci __P((fsm *, u_char *, int *, int)); /* Rcv CI */
110 static void ipcp_up __P((fsm *)); /* We're UP */
111 static void ipcp_down __P((fsm *)); /* We're DOWN */
112 static void ipcp_finished __P((fsm *)); /* Don't need lower layer */
113
114 fsm ipcp_fsm[NUM_PPP]; /* IPCP fsm structure */
115
116 static fsm_callbacks ipcp_callbacks = { /* IPCP callback routines */
117 ipcp_resetci, /* Reset our Configuration Information */
118 ipcp_cilen, /* Length of our Configuration Information */
119 ipcp_addci, /* Add our Configuration Information */
120 ipcp_ackci, /* ACK our Configuration Information */
121 ipcp_nakci, /* NAK our Configuration Information */
122 ipcp_rejci, /* Reject our Configuration Information */
123 ipcp_reqci, /* Request peer's Configuration Information */
124 ipcp_up, /* Called when fsm reaches OPENED state */
125 ipcp_down, /* Called when fsm leaves OPENED state */
126 NULL, /* Called when we want the lower layer up */
127 ipcp_finished, /* Called when we want the lower layer down */
128 NULL, /* Called when Protocol-Reject received */
129 NULL, /* Retransmission is necessary */
130 NULL, /* Called to handle protocol-specific codes */
131 "IPCP" /* String name of protocol */
132 };
133
134 /*
135 * Command-line options.
136 */
137 static int setvjslots __P((char **));
138 static int setdnsaddr __P((char **));
139 static int setwinsaddr __P((char **));
140 static int setnetmask __P((char **));
141 int setipaddr __P((char *, char **, int));
142 static void printipaddr __P((option_t *, void (*)(void *, char *,...),void *));
143
144 static option_t ipcp_option_list[] = {
145 { "noip", o_bool, &ipcp_protent.enabled_flag,
146 "Disable IP and IPCP" },
147 { "-ip", o_bool, &ipcp_protent.enabled_flag,
148 "Disable IP and IPCP", OPT_ALIAS },
149
150 { "novj", o_bool, &ipcp_wantoptions[0].neg_vj,
151 "Disable VJ compression", OPT_A2CLR, &ipcp_allowoptions[0].neg_vj },
152 { "-vj", o_bool, &ipcp_wantoptions[0].neg_vj,
153 "Disable VJ compression", OPT_ALIAS | OPT_A2CLR,
154 &ipcp_allowoptions[0].neg_vj },
155
156 { "novjccomp", o_bool, &ipcp_wantoptions[0].cflag,
157 "Disable VJ connection-ID compression", OPT_A2CLR,
158 &ipcp_allowoptions[0].cflag },
159 { "-vjccomp", o_bool, &ipcp_wantoptions[0].cflag,
160 "Disable VJ connection-ID compression", OPT_ALIAS | OPT_A2CLR,
161 &ipcp_allowoptions[0].cflag },
162
163 { "vj-max-slots", o_special, (void *)setvjslots,
164 "Set maximum VJ header slots",
165 OPT_PRIO | OPT_A2STRVAL | OPT_STATIC, vj_value },
166
167 { "ipcp-accept-local", o_bool, &ipcp_wantoptions[0].accept_local,
168 "Accept peer's address for us", 1 },
169 { "ipcp-accept-remote", o_bool, &ipcp_wantoptions[0].accept_remote,
170 "Accept peer's address for it", 1 },
171
172 { "ipparam", o_string, &ipparam,
173 "Set ip script parameter", OPT_PRIO },
174
175 { "noipdefault", o_bool, &disable_defaultip,
176 "Don't use name for default IP adrs", 1 },
177
178 { "ms-dns", 1, (void *)setdnsaddr,
179 "DNS address for the peer's use" },
180 { "ms-wins", 1, (void *)setwinsaddr,
181 "Nameserver for SMB over TCP/IP for peer" },
182
183 { "ipcp-restart", o_int, &ipcp_fsm[0].timeouttime,
184 "Set timeout for IPCP", OPT_PRIO },
185 { "ipcp-max-terminate", o_int, &ipcp_fsm[0].maxtermtransmits,
186 "Set max #xmits for term-reqs", OPT_PRIO },
187 { "ipcp-max-configure", o_int, &ipcp_fsm[0].maxconfreqtransmits,
188 "Set max #xmits for conf-reqs", OPT_PRIO },
189 { "ipcp-max-failure", o_int, &ipcp_fsm[0].maxnakloops,
190 "Set max #conf-naks for IPCP", OPT_PRIO },
191
192 { "defaultroute", o_bool, &ipcp_wantoptions[0].default_route,
193 "Add default route", OPT_ENABLE|1, &ipcp_allowoptions[0].default_route },
194 { "nodefaultroute", o_bool, &ipcp_allowoptions[0].default_route,
195 "disable defaultroute option", OPT_A2CLR,
196 &ipcp_wantoptions[0].default_route },
197 { "-defaultroute", o_bool, &ipcp_allowoptions[0].default_route,
198 "disable defaultroute option", OPT_ALIAS | OPT_A2CLR,
199 &ipcp_wantoptions[0].default_route },
200
201 { "proxyarp", o_bool, &ipcp_wantoptions[0].proxy_arp,
202 "Add proxy ARP entry", OPT_ENABLE|1, &ipcp_allowoptions[0].proxy_arp },
203 { "noproxyarp", o_bool, &ipcp_allowoptions[0].proxy_arp,
204 "disable proxyarp option", OPT_A2CLR,
205 &ipcp_wantoptions[0].proxy_arp },
206 { "-proxyarp", o_bool, &ipcp_allowoptions[0].proxy_arp,
207 "disable proxyarp option", OPT_ALIAS | OPT_A2CLR,
208 &ipcp_wantoptions[0].proxy_arp },
209
210 { "usepeerdns", o_bool, &usepeerdns,
211 "Ask peer for DNS address(es)", 1 },
212
213 { "netmask", o_special, (void *)setnetmask,
214 "set netmask", OPT_PRIO | OPT_A2STRVAL | OPT_STATIC, netmask_str },
215
216 { "ipcp-no-addresses", o_bool, &ipcp_wantoptions[0].old_addrs,
217 "Disable old-style IP-Addresses usage", OPT_A2CLR,
218 &ipcp_allowoptions[0].old_addrs },
219 { "ipcp-no-address", o_bool, &ipcp_wantoptions[0].neg_addr,
220 "Disable IP-Address usage", OPT_A2CLR,
221 &ipcp_allowoptions[0].neg_addr },
222 #ifdef __linux__
223 { "noremoteip", o_bool, &noremoteip,
224 "Allow peer to have no IP address", 1 },
225 #endif
226 { "nosendip", o_bool, &ipcp_wantoptions[0].neg_addr,
227 "Don't send our IP address to peer", OPT_A2CLR,
228 &ipcp_wantoptions[0].old_addrs},
229
230 { "IP addresses", o_wild, (void *) &setipaddr,
231 "set local and remote IP addresses",
232 OPT_NOARG | OPT_A2PRINTER, (void *) &printipaddr },
233
234 { NULL }
235 };
236
237 /*
238 * Protocol entry points from main code.
239 */
240 static void ipcp_init __P((int));
241 static void ipcp_open __P((int));
242 static void ipcp_close __P((int, char *));
243 static void ipcp_lowerup __P((int));
244 static void ipcp_lowerdown __P((int));
245 static void ipcp_input __P((int, u_char *, int));
246 static void ipcp_protrej __P((int));
247 static int ipcp_printpkt __P((u_char *, int,
248 void (*) __P((void *, char *, ...)), void *));
249 static void ip_check_options __P((void));
250 static int ip_demand_conf __P((int));
251 static int ip_active_pkt __P((u_char *, int));
252 static void create_resolv __P((u_int32_t, u_int32_t));
253
254 struct protent ipcp_protent = {
255 PPP_IPCP,
256 ipcp_init,
257 ipcp_input,
258 ipcp_protrej,
259 ipcp_lowerup,
260 ipcp_lowerdown,
261 ipcp_open,
262 ipcp_close,
263 ipcp_printpkt,
264 NULL,
265 1,
266 "IPCP",
267 "IP",
268 ipcp_option_list,
269 ip_check_options,
270 ip_demand_conf,
271 ip_active_pkt
272 };
273
274 static void ipcp_clear_addrs __P((int, u_int32_t, u_int32_t));
275 static void ipcp_script __P((char *, int)); /* Run an up/down script */
276 static void ipcp_script_done __P((void *));
277
278 /*
279 * Lengths of configuration options.
280 */
281 #define CILEN_VOID 2
282 #define CILEN_COMPRESS 4 /* min length for compression protocol opt. */
283 #define CILEN_VJ 6 /* length for RFC1332 Van-Jacobson opt. */
284 #define CILEN_ADDR 6 /* new-style single address option */
285 #define CILEN_ADDRS 10 /* old-style dual address option */
286
287
288 #define CODENAME(x) ((x) == CONFACK ? "ACK" : \
289 (x) == CONFNAK ? "NAK" : "REJ")
290
291 /*
292 * This state variable is used to ensure that we don't
293 * run an ipcp-up/down script while one is already running.
294 */
295 static enum script_state {
296 s_down,
297 s_up,
298 } ipcp_script_state;
299 static pid_t ipcp_script_pid;
300
301 /*
302 * Make a string representation of a network IP address.
303 */
304 char *
ip_ntoa(ipaddr)305 ip_ntoa(ipaddr)
306 u_int32_t ipaddr;
307 {
308 static char b[64];
309
310 slprintf(b, sizeof(b), "%I", ipaddr);
311 return b;
312 }
313
314 /*
315 * Option parsing.
316 */
317
318 /*
319 * setvjslots - set maximum number of connection slots for VJ compression
320 */
321 static int
setvjslots(argv)322 setvjslots(argv)
323 char **argv;
324 {
325 int value;
326
327 if (!int_option(*argv, &value))
328 return 0;
329 if (value < 2 || value > 16) {
330 option_error("vj-max-slots value must be between 2 and 16");
331 return 0;
332 }
333 ipcp_wantoptions [0].maxslotindex =
334 ipcp_allowoptions[0].maxslotindex = value - 1;
335 slprintf(vj_value, sizeof(vj_value), "%d", value);
336 return 1;
337 }
338
339 /*
340 * setdnsaddr - set the dns address(es)
341 */
342 static int
setdnsaddr(argv)343 setdnsaddr(argv)
344 char **argv;
345 {
346 u_int32_t dns;
347 struct hostent *hp;
348
349 dns = inet_addr(*argv);
350 if (dns == (u_int32_t) -1) {
351 if ((hp = gethostbyname(*argv)) == NULL) {
352 option_error("invalid address parameter '%s' for ms-dns option",
353 *argv);
354 return 0;
355 }
356 dns = *(u_int32_t *)hp->h_addr;
357 }
358
359 /* We take the last 2 values given, the 2nd-last as the primary
360 and the last as the secondary. If only one is given it
361 becomes both primary and secondary. */
362 if (ipcp_allowoptions[0].dnsaddr[1] == 0)
363 ipcp_allowoptions[0].dnsaddr[0] = dns;
364 else
365 ipcp_allowoptions[0].dnsaddr[0] = ipcp_allowoptions[0].dnsaddr[1];
366
367 /* always set the secondary address value. */
368 ipcp_allowoptions[0].dnsaddr[1] = dns;
369
370 return (1);
371 }
372
373 /*
374 * setwinsaddr - set the wins address(es)
375 * This is primrarly used with the Samba package under UNIX or for pointing
376 * the caller to the existing WINS server on a Windows NT platform.
377 */
378 static int
setwinsaddr(argv)379 setwinsaddr(argv)
380 char **argv;
381 {
382 u_int32_t wins;
383 struct hostent *hp;
384
385 wins = inet_addr(*argv);
386 if (wins == (u_int32_t) -1) {
387 if ((hp = gethostbyname(*argv)) == NULL) {
388 option_error("invalid address parameter '%s' for ms-wins option",
389 *argv);
390 return 0;
391 }
392 wins = *(u_int32_t *)hp->h_addr;
393 }
394
395 /* We take the last 2 values given, the 2nd-last as the primary
396 and the last as the secondary. If only one is given it
397 becomes both primary and secondary. */
398 if (ipcp_allowoptions[0].winsaddr[1] == 0)
399 ipcp_allowoptions[0].winsaddr[0] = wins;
400 else
401 ipcp_allowoptions[0].winsaddr[0] = ipcp_allowoptions[0].winsaddr[1];
402
403 /* always set the secondary address value. */
404 ipcp_allowoptions[0].winsaddr[1] = wins;
405
406 return (1);
407 }
408
409 /*
410 * setipaddr - Set the IP address
411 * If doit is 0, the call is to check whether this option is
412 * potentially an IP address specification.
413 * Not static so that plugins can call it to set the addresses
414 */
415 int
setipaddr(arg,argv,doit)416 setipaddr(arg, argv, doit)
417 char *arg;
418 char **argv;
419 int doit;
420 {
421 struct hostent *hp;
422 char *colon;
423 u_int32_t local, remote;
424 ipcp_options *wo = &ipcp_wantoptions[0];
425 static int prio_local = 0, prio_remote = 0;
426
427 /*
428 * IP address pair separated by ":".
429 */
430 if ((colon = strchr(arg, ':')) == NULL)
431 return 0;
432 if (!doit)
433 return 1;
434
435 /*
436 * If colon first character, then no local addr.
437 */
438 if (colon != arg && option_priority >= prio_local) {
439 *colon = '\0';
440 if ((local = inet_addr(arg)) == (u_int32_t) -1) {
441 if ((hp = gethostbyname(arg)) == NULL) {
442 option_error("unknown host: %s", arg);
443 return 0;
444 }
445 local = *(u_int32_t *)hp->h_addr;
446 }
447 if (bad_ip_adrs(local)) {
448 option_error("bad local IP address %s", ip_ntoa(local));
449 return 0;
450 }
451 if (local != 0)
452 wo->ouraddr = local;
453 *colon = ':';
454 prio_local = option_priority;
455 }
456
457 /*
458 * If colon last character, then no remote addr.
459 */
460 if (*++colon != '\0' && option_priority >= prio_remote) {
461 if ((remote = inet_addr(colon)) == (u_int32_t) -1) {
462 if ((hp = gethostbyname(colon)) == NULL) {
463 option_error("unknown host: %s", colon);
464 return 0;
465 }
466 remote = *(u_int32_t *)hp->h_addr;
467 if (remote_name[0] == 0)
468 strlcpy(remote_name, colon, sizeof(remote_name));
469 }
470 if (bad_ip_adrs(remote)) {
471 option_error("bad remote IP address %s", ip_ntoa(remote));
472 return 0;
473 }
474 if (remote != 0)
475 wo->hisaddr = remote;
476 prio_remote = option_priority;
477 }
478
479 return 1;
480 }
481
482 static void
printipaddr(opt,printer,arg)483 printipaddr(opt, printer, arg)
484 option_t *opt;
485 void (*printer) __P((void *, char *, ...));
486 void *arg;
487 {
488 ipcp_options *wo = &ipcp_wantoptions[0];
489
490 if (wo->ouraddr != 0)
491 printer(arg, "%I", wo->ouraddr);
492 printer(arg, ":");
493 if (wo->hisaddr != 0)
494 printer(arg, "%I", wo->hisaddr);
495 }
496
497 /*
498 * setnetmask - set the netmask to be used on the interface.
499 */
500 static int
setnetmask(argv)501 setnetmask(argv)
502 char **argv;
503 {
504 u_int32_t mask;
505 int n;
506 char *p;
507
508 /*
509 * Unfortunately, if we use inet_addr, we can't tell whether
510 * a result of all 1s is an error or a valid 255.255.255.255.
511 */
512 p = *argv;
513 n = parse_dotted_ip(p, &mask);
514
515 mask = htonl(mask);
516
517 if (n == 0 || p[n] != 0 || (netmask & ~mask) != 0) {
518 option_error("invalid netmask value '%s'", *argv);
519 return 0;
520 }
521
522 netmask = mask;
523 slprintf(netmask_str, sizeof(netmask_str), "%I", mask);
524
525 return (1);
526 }
527
528 int
parse_dotted_ip(p,vp)529 parse_dotted_ip(p, vp)
530 char *p;
531 u_int32_t *vp;
532 {
533 int n;
534 u_int32_t v, b;
535 char *endp, *p0 = p;
536
537 v = 0;
538 for (n = 3;; --n) {
539 b = strtoul(p, &endp, 0);
540 if (endp == p)
541 return 0;
542 if (b > 255) {
543 if (n < 3)
544 return 0;
545 /* accept e.g. 0xffffff00 */
546 *vp = b;
547 return endp - p0;
548 }
549 v |= b << (n * 8);
550 p = endp;
551 if (n == 0)
552 break;
553 if (*p != '.')
554 return 0;
555 ++p;
556 }
557 *vp = v;
558 return p - p0;
559 }
560
561
562 /*
563 * ipcp_init - Initialize IPCP.
564 */
565 static void
ipcp_init(unit)566 ipcp_init(unit)
567 int unit;
568 {
569 fsm *f = &ipcp_fsm[unit];
570 ipcp_options *wo = &ipcp_wantoptions[unit];
571 ipcp_options *ao = &ipcp_allowoptions[unit];
572
573 f->unit = unit;
574 f->protocol = PPP_IPCP;
575 f->callbacks = &ipcp_callbacks;
576 fsm_init(&ipcp_fsm[unit]);
577
578 /*
579 * Some 3G modems use repeated IPCP NAKs as a way of stalling
580 * until they can contact a server on the network, so we increase
581 * the default number of NAKs we accept before we start treating
582 * them as rejects.
583 */
584 f->maxnakloops = 100;
585
586 memset(wo, 0, sizeof(*wo));
587 memset(ao, 0, sizeof(*ao));
588
589 wo->neg_addr = wo->old_addrs = 1;
590 wo->neg_vj = 1;
591 wo->vj_protocol = IPCP_VJ_COMP;
592 wo->maxslotindex = MAX_STATES - 1; /* really max index */
593 wo->cflag = 1;
594
595
596 /* max slots and slot-id compression are currently hardwired in */
597 /* ppp_if.c to 16 and 1, this needs to be changed (among other */
598 /* things) gmc */
599
600 ao->neg_addr = ao->old_addrs = 1;
601 ao->neg_vj = 1;
602 ao->maxslotindex = MAX_STATES - 1;
603 ao->cflag = 1;
604
605 /*
606 * XXX These control whether the user may use the proxyarp
607 * and defaultroute options.
608 */
609 ao->proxy_arp = 1;
610 ao->default_route = 1;
611 }
612
613
614 /*
615 * ipcp_open - IPCP is allowed to come up.
616 */
617 static void
ipcp_open(unit)618 ipcp_open(unit)
619 int unit;
620 {
621 fsm_open(&ipcp_fsm[unit]);
622 ipcp_is_open = 1;
623 }
624
625
626 /*
627 * ipcp_close - Take IPCP down.
628 */
629 static void
ipcp_close(unit,reason)630 ipcp_close(unit, reason)
631 int unit;
632 char *reason;
633 {
634 fsm_close(&ipcp_fsm[unit], reason);
635 }
636
637
638 /*
639 * ipcp_lowerup - The lower layer is up.
640 */
641 static void
ipcp_lowerup(unit)642 ipcp_lowerup(unit)
643 int unit;
644 {
645 fsm_lowerup(&ipcp_fsm[unit]);
646 }
647
648
649 /*
650 * ipcp_lowerdown - The lower layer is down.
651 */
652 static void
ipcp_lowerdown(unit)653 ipcp_lowerdown(unit)
654 int unit;
655 {
656 fsm_lowerdown(&ipcp_fsm[unit]);
657 }
658
659
660 /*
661 * ipcp_input - Input IPCP packet.
662 */
663 static void
ipcp_input(unit,p,len)664 ipcp_input(unit, p, len)
665 int unit;
666 u_char *p;
667 int len;
668 {
669 fsm_input(&ipcp_fsm[unit], p, len);
670 }
671
672
673 /*
674 * ipcp_protrej - A Protocol-Reject was received for IPCP.
675 *
676 * Pretend the lower layer went down, so we shut up.
677 */
678 static void
ipcp_protrej(unit)679 ipcp_protrej(unit)
680 int unit;
681 {
682 fsm_lowerdown(&ipcp_fsm[unit]);
683 }
684
685
686 /*
687 * ipcp_resetci - Reset our CI.
688 * Called by fsm_sconfreq, Send Configure Request.
689 */
690 static void
ipcp_resetci(f)691 ipcp_resetci(f)
692 fsm *f;
693 {
694 ipcp_options *wo = &ipcp_wantoptions[f->unit];
695 ipcp_options *go = &ipcp_gotoptions[f->unit];
696 ipcp_options *ao = &ipcp_allowoptions[f->unit];
697
698 wo->req_addr = (wo->neg_addr || wo->old_addrs) &&
699 (ao->neg_addr || ao->old_addrs);
700 if (wo->ouraddr == 0)
701 wo->accept_local = 1;
702 if (wo->hisaddr == 0)
703 wo->accept_remote = 1;
704 wo->req_dns1 = usepeerdns; /* Request DNS addresses from the peer */
705 wo->req_dns2 = usepeerdns;
706 *go = *wo;
707 if (!ask_for_local)
708 go->ouraddr = 0;
709 if (ip_choose_hook) {
710 ip_choose_hook(&wo->hisaddr);
711 if (wo->hisaddr) {
712 wo->accept_remote = 0;
713 }
714 }
715 BZERO(&ipcp_hisoptions[f->unit], sizeof(ipcp_options));
716 }
717
718
719 /*
720 * ipcp_cilen - Return length of our CI.
721 * Called by fsm_sconfreq, Send Configure Request.
722 */
723 static int
ipcp_cilen(f)724 ipcp_cilen(f)
725 fsm *f;
726 {
727 ipcp_options *go = &ipcp_gotoptions[f->unit];
728 ipcp_options *wo = &ipcp_wantoptions[f->unit];
729 ipcp_options *ho = &ipcp_hisoptions[f->unit];
730
731 #define LENCIADDRS(neg) (neg ? CILEN_ADDRS : 0)
732 #define LENCIVJ(neg, old) (neg ? (old? CILEN_COMPRESS : CILEN_VJ) : 0)
733 #define LENCIADDR(neg) (neg ? CILEN_ADDR : 0)
734 #define LENCIDNS(neg) LENCIADDR(neg)
735 #define LENCIWINS(neg) LENCIADDR(neg)
736
737 /*
738 * First see if we want to change our options to the old
739 * forms because we have received old forms from the peer.
740 */
741 if (go->neg_addr && go->old_addrs && !ho->neg_addr && ho->old_addrs)
742 go->neg_addr = 0;
743 if (wo->neg_vj && !go->neg_vj && !go->old_vj) {
744 /* try an older style of VJ negotiation */
745 /* use the old style only if the peer did */
746 if (ho->neg_vj && ho->old_vj) {
747 go->neg_vj = 1;
748 go->old_vj = 1;
749 go->vj_protocol = ho->vj_protocol;
750 }
751 }
752
753 return (LENCIADDRS(!go->neg_addr && go->old_addrs) +
754 LENCIVJ(go->neg_vj, go->old_vj) +
755 LENCIADDR(go->neg_addr) +
756 LENCIDNS(go->req_dns1) +
757 LENCIDNS(go->req_dns2) +
758 LENCIWINS(go->winsaddr[0]) +
759 LENCIWINS(go->winsaddr[1])) ;
760 }
761
762
763 /*
764 * ipcp_addci - Add our desired CIs to a packet.
765 * Called by fsm_sconfreq, Send Configure Request.
766 */
767 static void
ipcp_addci(f,ucp,lenp)768 ipcp_addci(f, ucp, lenp)
769 fsm *f;
770 u_char *ucp;
771 int *lenp;
772 {
773 ipcp_options *go = &ipcp_gotoptions[f->unit];
774 int len = *lenp;
775
776 #define ADDCIADDRS(opt, neg, val1, val2) \
777 if (neg) { \
778 if (len >= CILEN_ADDRS) { \
779 u_int32_t l; \
780 PUTCHAR(opt, ucp); \
781 PUTCHAR(CILEN_ADDRS, ucp); \
782 l = ntohl(val1); \
783 PUTLONG(l, ucp); \
784 l = ntohl(val2); \
785 PUTLONG(l, ucp); \
786 len -= CILEN_ADDRS; \
787 } else \
788 go->old_addrs = 0; \
789 }
790
791 #define ADDCIVJ(opt, neg, val, old, maxslotindex, cflag) \
792 if (neg) { \
793 int vjlen = old? CILEN_COMPRESS : CILEN_VJ; \
794 if (len >= vjlen) { \
795 PUTCHAR(opt, ucp); \
796 PUTCHAR(vjlen, ucp); \
797 PUTSHORT(val, ucp); \
798 if (!old) { \
799 PUTCHAR(maxslotindex, ucp); \
800 PUTCHAR(cflag, ucp); \
801 } \
802 len -= vjlen; \
803 } else \
804 neg = 0; \
805 }
806
807 #define ADDCIADDR(opt, neg, val) \
808 if (neg) { \
809 if (len >= CILEN_ADDR) { \
810 u_int32_t l; \
811 PUTCHAR(opt, ucp); \
812 PUTCHAR(CILEN_ADDR, ucp); \
813 l = ntohl(val); \
814 PUTLONG(l, ucp); \
815 len -= CILEN_ADDR; \
816 } else \
817 neg = 0; \
818 }
819
820 #define ADDCIDNS(opt, neg, addr) \
821 if (neg) { \
822 if (len >= CILEN_ADDR) { \
823 u_int32_t l; \
824 PUTCHAR(opt, ucp); \
825 PUTCHAR(CILEN_ADDR, ucp); \
826 l = ntohl(addr); \
827 PUTLONG(l, ucp); \
828 len -= CILEN_ADDR; \
829 } else \
830 neg = 0; \
831 }
832
833 #define ADDCIWINS(opt, addr) \
834 if (addr) { \
835 if (len >= CILEN_ADDR) { \
836 u_int32_t l; \
837 PUTCHAR(opt, ucp); \
838 PUTCHAR(CILEN_ADDR, ucp); \
839 l = ntohl(addr); \
840 PUTLONG(l, ucp); \
841 len -= CILEN_ADDR; \
842 } else \
843 addr = 0; \
844 }
845
846 ADDCIADDRS(CI_ADDRS, !go->neg_addr && go->old_addrs, go->ouraddr,
847 go->hisaddr);
848
849 ADDCIVJ(CI_COMPRESSTYPE, go->neg_vj, go->vj_protocol, go->old_vj,
850 go->maxslotindex, go->cflag);
851
852 ADDCIADDR(CI_ADDR, go->neg_addr, go->ouraddr);
853
854 ADDCIDNS(CI_MS_DNS1, go->req_dns1, go->dnsaddr[0]);
855
856 ADDCIDNS(CI_MS_DNS2, go->req_dns2, go->dnsaddr[1]);
857
858 ADDCIWINS(CI_MS_WINS1, go->winsaddr[0]);
859
860 ADDCIWINS(CI_MS_WINS2, go->winsaddr[1]);
861
862 *lenp -= len;
863 }
864
865
866 /*
867 * ipcp_ackci - Ack our CIs.
868 * Called by fsm_rconfack, Receive Configure ACK.
869 *
870 * Returns:
871 * 0 - Ack was bad.
872 * 1 - Ack was good.
873 */
874 static int
ipcp_ackci(f,p,len)875 ipcp_ackci(f, p, len)
876 fsm *f;
877 u_char *p;
878 int len;
879 {
880 ipcp_options *go = &ipcp_gotoptions[f->unit];
881 u_short cilen, citype, cishort;
882 u_int32_t cilong;
883 u_char cimaxslotindex, cicflag;
884
885 /*
886 * CIs must be in exactly the same order that we sent...
887 * Check packet length and CI length at each step.
888 * If we find any deviations, then this packet is bad.
889 */
890
891 #define ACKCIADDRS(opt, neg, val1, val2) \
892 if (neg) { \
893 u_int32_t l; \
894 if ((len -= CILEN_ADDRS) < 0) \
895 goto bad; \
896 GETCHAR(citype, p); \
897 GETCHAR(cilen, p); \
898 if (cilen != CILEN_ADDRS || \
899 citype != opt) \
900 goto bad; \
901 GETLONG(l, p); \
902 cilong = htonl(l); \
903 if (val1 != cilong) \
904 goto bad; \
905 GETLONG(l, p); \
906 cilong = htonl(l); \
907 if (val2 != cilong) \
908 goto bad; \
909 }
910
911 #define ACKCIVJ(opt, neg, val, old, maxslotindex, cflag) \
912 if (neg) { \
913 int vjlen = old? CILEN_COMPRESS : CILEN_VJ; \
914 if ((len -= vjlen) < 0) \
915 goto bad; \
916 GETCHAR(citype, p); \
917 GETCHAR(cilen, p); \
918 if (cilen != vjlen || \
919 citype != opt) \
920 goto bad; \
921 GETSHORT(cishort, p); \
922 if (cishort != val) \
923 goto bad; \
924 if (!old) { \
925 GETCHAR(cimaxslotindex, p); \
926 if (cimaxslotindex != maxslotindex) \
927 goto bad; \
928 GETCHAR(cicflag, p); \
929 if (cicflag != cflag) \
930 goto bad; \
931 } \
932 }
933
934 #define ACKCIADDR(opt, neg, val) \
935 if (neg) { \
936 u_int32_t l; \
937 if ((len -= CILEN_ADDR) < 0) \
938 goto bad; \
939 GETCHAR(citype, p); \
940 GETCHAR(cilen, p); \
941 if (cilen != CILEN_ADDR || \
942 citype != opt) \
943 goto bad; \
944 GETLONG(l, p); \
945 cilong = htonl(l); \
946 if (val != cilong) \
947 goto bad; \
948 }
949
950 #define ACKCIDNS(opt, neg, addr) \
951 if (neg) { \
952 u_int32_t l; \
953 if ((len -= CILEN_ADDR) < 0) \
954 goto bad; \
955 GETCHAR(citype, p); \
956 GETCHAR(cilen, p); \
957 if (cilen != CILEN_ADDR || citype != opt) \
958 goto bad; \
959 GETLONG(l, p); \
960 cilong = htonl(l); \
961 if (addr != cilong) \
962 goto bad; \
963 }
964
965 #define ACKCIWINS(opt, addr) \
966 if (addr) { \
967 u_int32_t l; \
968 if ((len -= CILEN_ADDR) < 0) \
969 goto bad; \
970 GETCHAR(citype, p); \
971 GETCHAR(cilen, p); \
972 if (cilen != CILEN_ADDR || citype != opt) \
973 goto bad; \
974 GETLONG(l, p); \
975 cilong = htonl(l); \
976 if (addr != cilong) \
977 goto bad; \
978 }
979
980 ACKCIADDRS(CI_ADDRS, !go->neg_addr && go->old_addrs, go->ouraddr,
981 go->hisaddr);
982
983 ACKCIVJ(CI_COMPRESSTYPE, go->neg_vj, go->vj_protocol, go->old_vj,
984 go->maxslotindex, go->cflag);
985
986 ACKCIADDR(CI_ADDR, go->neg_addr, go->ouraddr);
987
988 ACKCIDNS(CI_MS_DNS1, go->req_dns1, go->dnsaddr[0]);
989
990 ACKCIDNS(CI_MS_DNS2, go->req_dns2, go->dnsaddr[1]);
991
992 ACKCIWINS(CI_MS_WINS1, go->winsaddr[0]);
993
994 ACKCIWINS(CI_MS_WINS2, go->winsaddr[1]);
995
996 /*
997 * If there are any remaining CIs, then this packet is bad.
998 */
999 if (len != 0)
1000 goto bad;
1001 return (1);
1002
1003 bad:
1004 IPCPDEBUG(("ipcp_ackci: received bad Ack!"));
1005 return (0);
1006 }
1007
1008 /*
1009 * ipcp_nakci - Peer has sent a NAK for some of our CIs.
1010 * This should not modify any state if the Nak is bad
1011 * or if IPCP is in the OPENED state.
1012 * Calback from fsm_rconfnakrej - Receive Configure-Nak or Configure-Reject.
1013 *
1014 * Returns:
1015 * 0 - Nak was bad.
1016 * 1 - Nak was good.
1017 */
1018 static int
ipcp_nakci(f,p,len,treat_as_reject)1019 ipcp_nakci(f, p, len, treat_as_reject)
1020 fsm *f;
1021 u_char *p;
1022 int len;
1023 int treat_as_reject;
1024 {
1025 ipcp_options *go = &ipcp_gotoptions[f->unit];
1026 u_char cimaxslotindex, cicflag;
1027 u_char citype, cilen, *next;
1028 u_short cishort;
1029 u_int32_t ciaddr1, ciaddr2, l, cidnsaddr;
1030 ipcp_options no; /* options we've seen Naks for */
1031 ipcp_options try; /* options to request next time */
1032
1033 BZERO(&no, sizeof(no));
1034 try = *go;
1035
1036 /*
1037 * Any Nak'd CIs must be in exactly the same order that we sent.
1038 * Check packet length and CI length at each step.
1039 * If we find any deviations, then this packet is bad.
1040 */
1041 #define NAKCIADDRS(opt, neg, code) \
1042 if ((neg) && \
1043 (cilen = p[1]) == CILEN_ADDRS && \
1044 len >= cilen && \
1045 p[0] == opt) { \
1046 len -= cilen; \
1047 INCPTR(2, p); \
1048 GETLONG(l, p); \
1049 ciaddr1 = htonl(l); \
1050 GETLONG(l, p); \
1051 ciaddr2 = htonl(l); \
1052 no.old_addrs = 1; \
1053 code \
1054 }
1055
1056 #define NAKCIVJ(opt, neg, code) \
1057 if (go->neg && \
1058 ((cilen = p[1]) == CILEN_COMPRESS || cilen == CILEN_VJ) && \
1059 len >= cilen && \
1060 p[0] == opt) { \
1061 len -= cilen; \
1062 INCPTR(2, p); \
1063 GETSHORT(cishort, p); \
1064 no.neg = 1; \
1065 code \
1066 }
1067
1068 #define NAKCIADDR(opt, neg, code) \
1069 if (go->neg && \
1070 (cilen = p[1]) == CILEN_ADDR && \
1071 len >= cilen && \
1072 p[0] == opt) { \
1073 len -= cilen; \
1074 INCPTR(2, p); \
1075 GETLONG(l, p); \
1076 ciaddr1 = htonl(l); \
1077 no.neg = 1; \
1078 code \
1079 }
1080
1081 #define NAKCIDNS(opt, neg, code) \
1082 if (go->neg && \
1083 ((cilen = p[1]) == CILEN_ADDR) && \
1084 len >= cilen && \
1085 p[0] == opt) { \
1086 len -= cilen; \
1087 INCPTR(2, p); \
1088 GETLONG(l, p); \
1089 cidnsaddr = htonl(l); \
1090 no.neg = 1; \
1091 code \
1092 }
1093
1094 /*
1095 * Accept the peer's idea of {our,his} address, if different
1096 * from our idea, only if the accept_{local,remote} flag is set.
1097 */
1098 NAKCIADDRS(CI_ADDRS, !go->neg_addr && go->old_addrs,
1099 if (treat_as_reject) {
1100 try.old_addrs = 0;
1101 } else {
1102 if (go->accept_local && ciaddr1) {
1103 /* take his idea of our address */
1104 try.ouraddr = ciaddr1;
1105 }
1106 if (go->accept_remote && ciaddr2) {
1107 /* take his idea of his address */
1108 try.hisaddr = ciaddr2;
1109 }
1110 }
1111 );
1112
1113 /*
1114 * Accept the peer's value of maxslotindex provided that it
1115 * is less than what we asked for. Turn off slot-ID compression
1116 * if the peer wants. Send old-style compress-type option if
1117 * the peer wants.
1118 */
1119 NAKCIVJ(CI_COMPRESSTYPE, neg_vj,
1120 if (treat_as_reject) {
1121 try.neg_vj = 0;
1122 } else if (cilen == CILEN_VJ) {
1123 GETCHAR(cimaxslotindex, p);
1124 GETCHAR(cicflag, p);
1125 if (cishort == IPCP_VJ_COMP) {
1126 try.old_vj = 0;
1127 if (cimaxslotindex < go->maxslotindex)
1128 try.maxslotindex = cimaxslotindex;
1129 if (!cicflag)
1130 try.cflag = 0;
1131 } else {
1132 try.neg_vj = 0;
1133 }
1134 } else {
1135 if (cishort == IPCP_VJ_COMP || cishort == IPCP_VJ_COMP_OLD) {
1136 try.old_vj = 1;
1137 try.vj_protocol = cishort;
1138 } else {
1139 try.neg_vj = 0;
1140 }
1141 }
1142 );
1143
1144 NAKCIADDR(CI_ADDR, neg_addr,
1145 if (treat_as_reject) {
1146 try.neg_addr = 0;
1147 try.old_addrs = 0;
1148 } else if (go->accept_local && ciaddr1) {
1149 /* take his idea of our address */
1150 try.ouraddr = ciaddr1;
1151 }
1152 );
1153
1154 NAKCIDNS(CI_MS_DNS1, req_dns1,
1155 if (treat_as_reject) {
1156 try.req_dns1 = 0;
1157 } else {
1158 try.dnsaddr[0] = cidnsaddr;
1159 }
1160 );
1161
1162 NAKCIDNS(CI_MS_DNS2, req_dns2,
1163 if (treat_as_reject) {
1164 try.req_dns2 = 0;
1165 } else {
1166 try.dnsaddr[1] = cidnsaddr;
1167 }
1168 );
1169
1170 /*
1171 * There may be remaining CIs, if the peer is requesting negotiation
1172 * on an option that we didn't include in our request packet.
1173 * If they want to negotiate about IP addresses, we comply.
1174 * If they want us to ask for compression, we refuse.
1175 * If they want us to ask for ms-dns, we do that, since some
1176 * peers get huffy if we don't.
1177 */
1178 while (len >= CILEN_VOID) {
1179 GETCHAR(citype, p);
1180 GETCHAR(cilen, p);
1181 if ( cilen < CILEN_VOID || (len -= cilen) < 0 )
1182 goto bad;
1183 next = p + cilen - 2;
1184
1185 switch (citype) {
1186 case CI_COMPRESSTYPE:
1187 if (go->neg_vj || no.neg_vj ||
1188 (cilen != CILEN_VJ && cilen != CILEN_COMPRESS))
1189 goto bad;
1190 no.neg_vj = 1;
1191 break;
1192 case CI_ADDRS:
1193 if ((!go->neg_addr && go->old_addrs) || no.old_addrs
1194 || cilen != CILEN_ADDRS)
1195 goto bad;
1196 try.neg_addr = 0;
1197 GETLONG(l, p);
1198 ciaddr1 = htonl(l);
1199 if (ciaddr1 && go->accept_local)
1200 try.ouraddr = ciaddr1;
1201 GETLONG(l, p);
1202 ciaddr2 = htonl(l);
1203 if (ciaddr2 && go->accept_remote)
1204 try.hisaddr = ciaddr2;
1205 no.old_addrs = 1;
1206 break;
1207 case CI_ADDR:
1208 if (go->neg_addr || no.neg_addr || cilen != CILEN_ADDR)
1209 goto bad;
1210 try.old_addrs = 0;
1211 GETLONG(l, p);
1212 ciaddr1 = htonl(l);
1213 if (ciaddr1 && go->accept_local)
1214 try.ouraddr = ciaddr1;
1215 if (try.ouraddr != 0)
1216 try.neg_addr = 1;
1217 no.neg_addr = 1;
1218 break;
1219 case CI_MS_DNS1:
1220 if (go->req_dns1 || no.req_dns1 || cilen != CILEN_ADDR)
1221 goto bad;
1222 GETLONG(l, p);
1223 try.dnsaddr[0] = htonl(l);
1224 try.req_dns1 = 1;
1225 no.req_dns1 = 1;
1226 break;
1227 case CI_MS_DNS2:
1228 if (go->req_dns2 || no.req_dns2 || cilen != CILEN_ADDR)
1229 goto bad;
1230 GETLONG(l, p);
1231 try.dnsaddr[1] = htonl(l);
1232 try.req_dns2 = 1;
1233 no.req_dns2 = 1;
1234 break;
1235 case CI_MS_WINS1:
1236 case CI_MS_WINS2:
1237 if (cilen != CILEN_ADDR)
1238 goto bad;
1239 GETLONG(l, p);
1240 ciaddr1 = htonl(l);
1241 if (ciaddr1)
1242 try.winsaddr[citype == CI_MS_WINS2] = ciaddr1;
1243 break;
1244 }
1245 p = next;
1246 }
1247
1248 /*
1249 * OK, the Nak is good. Now we can update state.
1250 * If there are any remaining options, we ignore them.
1251 */
1252 if (f->state != OPENED)
1253 *go = try;
1254
1255 return 1;
1256
1257 bad:
1258 IPCPDEBUG(("ipcp_nakci: received bad Nak!"));
1259 return 0;
1260 }
1261
1262
1263 /*
1264 * ipcp_rejci - Reject some of our CIs.
1265 * Callback from fsm_rconfnakrej.
1266 */
1267 static int
ipcp_rejci(f,p,len)1268 ipcp_rejci(f, p, len)
1269 fsm *f;
1270 u_char *p;
1271 int len;
1272 {
1273 ipcp_options *go = &ipcp_gotoptions[f->unit];
1274 u_char cimaxslotindex, ciflag, cilen;
1275 u_short cishort;
1276 u_int32_t cilong;
1277 ipcp_options try; /* options to request next time */
1278
1279 try = *go;
1280 /*
1281 * Any Rejected CIs must be in exactly the same order that we sent.
1282 * Check packet length and CI length at each step.
1283 * If we find any deviations, then this packet is bad.
1284 */
1285 #define REJCIADDRS(opt, neg, val1, val2) \
1286 if ((neg) && \
1287 (cilen = p[1]) == CILEN_ADDRS && \
1288 len >= cilen && \
1289 p[0] == opt) { \
1290 u_int32_t l; \
1291 len -= cilen; \
1292 INCPTR(2, p); \
1293 GETLONG(l, p); \
1294 cilong = htonl(l); \
1295 /* Check rejected value. */ \
1296 if (cilong != val1) \
1297 goto bad; \
1298 GETLONG(l, p); \
1299 cilong = htonl(l); \
1300 /* Check rejected value. */ \
1301 if (cilong != val2) \
1302 goto bad; \
1303 try.old_addrs = 0; \
1304 }
1305
1306 #define REJCIVJ(opt, neg, val, old, maxslot, cflag) \
1307 if (go->neg && \
1308 p[1] == (old? CILEN_COMPRESS : CILEN_VJ) && \
1309 len >= p[1] && \
1310 p[0] == opt) { \
1311 len -= p[1]; \
1312 INCPTR(2, p); \
1313 GETSHORT(cishort, p); \
1314 /* Check rejected value. */ \
1315 if (cishort != val) \
1316 goto bad; \
1317 if (!old) { \
1318 GETCHAR(cimaxslotindex, p); \
1319 if (cimaxslotindex != maxslot) \
1320 goto bad; \
1321 GETCHAR(ciflag, p); \
1322 if (ciflag != cflag) \
1323 goto bad; \
1324 } \
1325 try.neg = 0; \
1326 }
1327
1328 #define REJCIADDR(opt, neg, val) \
1329 if (go->neg && \
1330 (cilen = p[1]) == CILEN_ADDR && \
1331 len >= cilen && \
1332 p[0] == opt) { \
1333 u_int32_t l; \
1334 len -= cilen; \
1335 INCPTR(2, p); \
1336 GETLONG(l, p); \
1337 cilong = htonl(l); \
1338 /* Check rejected value. */ \
1339 if (cilong != val) \
1340 goto bad; \
1341 try.neg = 0; \
1342 }
1343
1344 #define REJCIDNS(opt, neg, dnsaddr) \
1345 if (go->neg && \
1346 ((cilen = p[1]) == CILEN_ADDR) && \
1347 len >= cilen && \
1348 p[0] == opt) { \
1349 u_int32_t l; \
1350 len -= cilen; \
1351 INCPTR(2, p); \
1352 GETLONG(l, p); \
1353 cilong = htonl(l); \
1354 /* Check rejected value. */ \
1355 if (cilong != dnsaddr) \
1356 goto bad; \
1357 try.neg = 0; \
1358 }
1359
1360 #define REJCIWINS(opt, addr) \
1361 if (addr && \
1362 ((cilen = p[1]) == CILEN_ADDR) && \
1363 len >= cilen && \
1364 p[0] == opt) { \
1365 u_int32_t l; \
1366 len -= cilen; \
1367 INCPTR(2, p); \
1368 GETLONG(l, p); \
1369 cilong = htonl(l); \
1370 /* Check rejected value. */ \
1371 if (cilong != addr) \
1372 goto bad; \
1373 try.winsaddr[opt == CI_MS_WINS2] = 0; \
1374 }
1375
1376 REJCIADDRS(CI_ADDRS, !go->neg_addr && go->old_addrs,
1377 go->ouraddr, go->hisaddr);
1378
1379 REJCIVJ(CI_COMPRESSTYPE, neg_vj, go->vj_protocol, go->old_vj,
1380 go->maxslotindex, go->cflag);
1381
1382 REJCIADDR(CI_ADDR, neg_addr, go->ouraddr);
1383
1384 REJCIDNS(CI_MS_DNS1, req_dns1, go->dnsaddr[0]);
1385
1386 REJCIDNS(CI_MS_DNS2, req_dns2, go->dnsaddr[1]);
1387
1388 REJCIWINS(CI_MS_WINS1, go->winsaddr[0]);
1389
1390 REJCIWINS(CI_MS_WINS2, go->winsaddr[1]);
1391
1392 /*
1393 * If there are any remaining CIs, then this packet is bad.
1394 */
1395 if (len != 0)
1396 goto bad;
1397 /*
1398 * Now we can update state.
1399 */
1400 if (f->state != OPENED)
1401 *go = try;
1402 return 1;
1403
1404 bad:
1405 IPCPDEBUG(("ipcp_rejci: received bad Reject!"));
1406 return 0;
1407 }
1408
1409
1410 /*
1411 * ipcp_reqci - Check the peer's requested CIs and send appropriate response.
1412 * Callback from fsm_rconfreq, Receive Configure Request
1413 *
1414 * Returns: CONFACK, CONFNAK or CONFREJ and input packet modified
1415 * appropriately. If reject_if_disagree is non-zero, doesn't return
1416 * CONFNAK; returns CONFREJ if it can't return CONFACK.
1417 */
1418 static int
ipcp_reqci(f,inp,len,reject_if_disagree)1419 ipcp_reqci(f, inp, len, reject_if_disagree)
1420 fsm *f;
1421 u_char *inp; /* Requested CIs */
1422 int *len; /* Length of requested CIs */
1423 int reject_if_disagree;
1424 {
1425 ipcp_options *wo = &ipcp_wantoptions[f->unit];
1426 ipcp_options *ho = &ipcp_hisoptions[f->unit];
1427 ipcp_options *ao = &ipcp_allowoptions[f->unit];
1428 u_char *cip, *next; /* Pointer to current and next CIs */
1429 u_short cilen, citype; /* Parsed len, type */
1430 u_short cishort; /* Parsed short value */
1431 u_int32_t tl, ciaddr1, ciaddr2;/* Parsed address values */
1432 int rc = CONFACK; /* Final packet return code */
1433 int orc; /* Individual option return code */
1434 u_char *p; /* Pointer to next char to parse */
1435 u_char *ucp = inp; /* Pointer to current output char */
1436 int l = *len; /* Length left */
1437 u_char maxslotindex, cflag;
1438 int d;
1439
1440 /*
1441 * Reset all his options.
1442 */
1443 BZERO(ho, sizeof(*ho));
1444
1445 /*
1446 * Process all his options.
1447 */
1448 next = inp;
1449 while (l) {
1450 orc = CONFACK; /* Assume success */
1451 cip = p = next; /* Remember begining of CI */
1452 if (l < 2 || /* Not enough data for CI header or */
1453 p[1] < 2 || /* CI length too small or */
1454 p[1] > l) { /* CI length too big? */
1455 IPCPDEBUG(("ipcp_reqci: bad CI length!"));
1456 orc = CONFREJ; /* Reject bad CI */
1457 cilen = l; /* Reject till end of packet */
1458 l = 0; /* Don't loop again */
1459 goto endswitch;
1460 }
1461 GETCHAR(citype, p); /* Parse CI type */
1462 GETCHAR(cilen, p); /* Parse CI length */
1463 l -= cilen; /* Adjust remaining length */
1464 next += cilen; /* Step to next CI */
1465
1466 switch (citype) { /* Check CI type */
1467 case CI_ADDRS:
1468 if (!ao->old_addrs || ho->neg_addr ||
1469 cilen != CILEN_ADDRS) { /* Check CI length */
1470 orc = CONFREJ; /* Reject CI */
1471 break;
1472 }
1473
1474 /*
1475 * If he has no address, or if we both have his address but
1476 * disagree about it, then NAK it with our idea.
1477 * In particular, if we don't know his address, but he does,
1478 * then accept it.
1479 */
1480 GETLONG(tl, p); /* Parse source address (his) */
1481 ciaddr1 = htonl(tl);
1482 if (ciaddr1 != wo->hisaddr
1483 && (ciaddr1 == 0 || !wo->accept_remote)) {
1484 orc = CONFNAK;
1485 if (!reject_if_disagree) {
1486 DECPTR(sizeof(u_int32_t), p);
1487 tl = ntohl(wo->hisaddr);
1488 PUTLONG(tl, p);
1489 }
1490 } else if (ciaddr1 == 0 && wo->hisaddr == 0) {
1491 /*
1492 * If neither we nor he knows his address, reject the option.
1493 */
1494 orc = CONFREJ;
1495 wo->req_addr = 0; /* don't NAK with 0.0.0.0 later */
1496 break;
1497 }
1498
1499 /*
1500 * If he doesn't know our address, or if we both have our address
1501 * but disagree about it, then NAK it with our idea.
1502 */
1503 GETLONG(tl, p); /* Parse desination address (ours) */
1504 ciaddr2 = htonl(tl);
1505 if (ciaddr2 != wo->ouraddr) {
1506 if (ciaddr2 == 0 || !wo->accept_local) {
1507 orc = CONFNAK;
1508 if (!reject_if_disagree) {
1509 DECPTR(sizeof(u_int32_t), p);
1510 tl = ntohl(wo->ouraddr);
1511 PUTLONG(tl, p);
1512 }
1513 } else {
1514 wo->ouraddr = ciaddr2; /* accept peer's idea */
1515 }
1516 }
1517
1518 ho->old_addrs = 1;
1519 ho->hisaddr = ciaddr1;
1520 ho->ouraddr = ciaddr2;
1521 break;
1522
1523 case CI_ADDR:
1524 if (!ao->neg_addr || ho->old_addrs ||
1525 cilen != CILEN_ADDR) { /* Check CI length */
1526 orc = CONFREJ; /* Reject CI */
1527 break;
1528 }
1529
1530 /*
1531 * If he has no address, or if we both have his address but
1532 * disagree about it, then NAK it with our idea.
1533 * In particular, if we don't know his address, but he does,
1534 * then accept it.
1535 */
1536 GETLONG(tl, p); /* Parse source address (his) */
1537 ciaddr1 = htonl(tl);
1538 if (ciaddr1 != wo->hisaddr
1539 && (ciaddr1 == 0 || !wo->accept_remote)) {
1540 orc = CONFNAK;
1541 if (!reject_if_disagree) {
1542 DECPTR(sizeof(u_int32_t), p);
1543 tl = ntohl(wo->hisaddr);
1544 PUTLONG(tl, p);
1545 }
1546 } else if (ciaddr1 == 0 && wo->hisaddr == 0) {
1547 /*
1548 * Don't ACK an address of 0.0.0.0 - reject it instead.
1549 */
1550 orc = CONFREJ;
1551 wo->req_addr = 0; /* don't NAK with 0.0.0.0 later */
1552 break;
1553 }
1554
1555 ho->neg_addr = 1;
1556 ho->hisaddr = ciaddr1;
1557 break;
1558
1559 case CI_MS_DNS1:
1560 case CI_MS_DNS2:
1561 /* Microsoft primary or secondary DNS request */
1562 d = citype == CI_MS_DNS2;
1563
1564 /* If we do not have a DNS address then we cannot send it */
1565 if (ao->dnsaddr[d] == 0 ||
1566 cilen != CILEN_ADDR) { /* Check CI length */
1567 orc = CONFREJ; /* Reject CI */
1568 break;
1569 }
1570 GETLONG(tl, p);
1571 if (htonl(tl) != ao->dnsaddr[d]) {
1572 DECPTR(sizeof(u_int32_t), p);
1573 tl = ntohl(ao->dnsaddr[d]);
1574 PUTLONG(tl, p);
1575 orc = CONFNAK;
1576 }
1577 break;
1578
1579 case CI_MS_WINS1:
1580 case CI_MS_WINS2:
1581 /* Microsoft primary or secondary WINS request */
1582 d = citype == CI_MS_WINS2;
1583
1584 /* If we do not have a DNS address then we cannot send it */
1585 if (ao->winsaddr[d] == 0 ||
1586 cilen != CILEN_ADDR) { /* Check CI length */
1587 orc = CONFREJ; /* Reject CI */
1588 break;
1589 }
1590 GETLONG(tl, p);
1591 if (htonl(tl) != ao->winsaddr[d]) {
1592 DECPTR(sizeof(u_int32_t), p);
1593 tl = ntohl(ao->winsaddr[d]);
1594 PUTLONG(tl, p);
1595 orc = CONFNAK;
1596 }
1597 break;
1598
1599 case CI_COMPRESSTYPE:
1600 if (!ao->neg_vj ||
1601 (cilen != CILEN_VJ && cilen != CILEN_COMPRESS)) {
1602 orc = CONFREJ;
1603 break;
1604 }
1605 GETSHORT(cishort, p);
1606
1607 if (!(cishort == IPCP_VJ_COMP ||
1608 (cishort == IPCP_VJ_COMP_OLD && cilen == CILEN_COMPRESS))) {
1609 orc = CONFREJ;
1610 break;
1611 }
1612
1613 ho->neg_vj = 1;
1614 ho->vj_protocol = cishort;
1615 if (cilen == CILEN_VJ) {
1616 GETCHAR(maxslotindex, p);
1617 if (maxslotindex > ao->maxslotindex) {
1618 orc = CONFNAK;
1619 if (!reject_if_disagree){
1620 DECPTR(1, p);
1621 PUTCHAR(ao->maxslotindex, p);
1622 }
1623 }
1624 GETCHAR(cflag, p);
1625 if (cflag && !ao->cflag) {
1626 orc = CONFNAK;
1627 if (!reject_if_disagree){
1628 DECPTR(1, p);
1629 PUTCHAR(wo->cflag, p);
1630 }
1631 }
1632 ho->maxslotindex = maxslotindex;
1633 ho->cflag = cflag;
1634 } else {
1635 ho->old_vj = 1;
1636 ho->maxslotindex = MAX_STATES - 1;
1637 ho->cflag = 1;
1638 }
1639 break;
1640
1641 default:
1642 orc = CONFREJ;
1643 break;
1644 }
1645 endswitch:
1646 if (orc == CONFACK && /* Good CI */
1647 rc != CONFACK) /* but prior CI wasnt? */
1648 continue; /* Don't send this one */
1649
1650 if (orc == CONFNAK) { /* Nak this CI? */
1651 if (reject_if_disagree) /* Getting fed up with sending NAKs? */
1652 orc = CONFREJ; /* Get tough if so */
1653 else {
1654 if (rc == CONFREJ) /* Rejecting prior CI? */
1655 continue; /* Don't send this one */
1656 if (rc == CONFACK) { /* Ack'd all prior CIs? */
1657 rc = CONFNAK; /* Not anymore... */
1658 ucp = inp; /* Backup */
1659 }
1660 }
1661 }
1662
1663 if (orc == CONFREJ && /* Reject this CI */
1664 rc != CONFREJ) { /* but no prior ones? */
1665 rc = CONFREJ;
1666 ucp = inp; /* Backup */
1667 }
1668
1669 /* Need to move CI? */
1670 if (ucp != cip)
1671 BCOPY(cip, ucp, cilen); /* Move it */
1672
1673 /* Update output pointer */
1674 INCPTR(cilen, ucp);
1675 }
1676
1677 /*
1678 * If we aren't rejecting this packet, and we want to negotiate
1679 * their address, and they didn't send their address, then we
1680 * send a NAK with a CI_ADDR option appended. We assume the
1681 * input buffer is long enough that we can append the extra
1682 * option safely.
1683 */
1684 if (rc != CONFREJ && !ho->neg_addr && !ho->old_addrs &&
1685 wo->req_addr && !reject_if_disagree && !noremoteip) {
1686 if (rc == CONFACK) {
1687 rc = CONFNAK;
1688 ucp = inp; /* reset pointer */
1689 wo->req_addr = 0; /* don't ask again */
1690 }
1691 PUTCHAR(CI_ADDR, ucp);
1692 PUTCHAR(CILEN_ADDR, ucp);
1693 tl = ntohl(wo->hisaddr);
1694 PUTLONG(tl, ucp);
1695 }
1696
1697 *len = ucp - inp; /* Compute output length */
1698 IPCPDEBUG(("ipcp: returning Configure-%s", CODENAME(rc)));
1699 return (rc); /* Return final code */
1700 }
1701
1702
1703 /*
1704 * ip_check_options - check that any IP-related options are OK,
1705 * and assign appropriate defaults.
1706 */
1707 static void
ip_check_options()1708 ip_check_options()
1709 {
1710 struct hostent *hp;
1711 u_int32_t local;
1712 ipcp_options *wo = &ipcp_wantoptions[0];
1713
1714 /*
1715 * Default our local IP address based on our hostname.
1716 * If local IP address already given, don't bother.
1717 */
1718 if (wo->ouraddr == 0 && !disable_defaultip) {
1719 /*
1720 * Look up our hostname (possibly with domain name appended)
1721 * and take the first IP address as our local IP address.
1722 * If there isn't an IP address for our hostname, too bad.
1723 */
1724 wo->accept_local = 1; /* don't insist on this default value */
1725 if ((hp = gethostbyname(hostname)) != NULL) {
1726 local = *(u_int32_t *)hp->h_addr;
1727 if (local != 0 && !bad_ip_adrs(local))
1728 wo->ouraddr = local;
1729 }
1730 }
1731 ask_for_local = wo->ouraddr != 0 || !disable_defaultip;
1732 }
1733
1734
1735 /*
1736 * ip_demand_conf - configure the interface as though
1737 * IPCP were up, for use with dial-on-demand.
1738 */
1739 static int
ip_demand_conf(u)1740 ip_demand_conf(u)
1741 int u;
1742 {
1743 ipcp_options *wo = &ipcp_wantoptions[u];
1744
1745 if (wo->hisaddr == 0 && !noremoteip) {
1746 /* make up an arbitrary address for the peer */
1747 wo->hisaddr = htonl(0x0a707070 + ifunit);
1748 wo->accept_remote = 1;
1749 }
1750 if (wo->ouraddr == 0) {
1751 /* make up an arbitrary address for us */
1752 wo->ouraddr = htonl(0x0a404040 + ifunit);
1753 wo->accept_local = 1;
1754 ask_for_local = 0; /* don't tell the peer this address */
1755 }
1756 if (!sifaddr(u, wo->ouraddr, wo->hisaddr, GetMask(wo->ouraddr)))
1757 return 0;
1758 ipcp_script(_PATH_IPPREUP, 1);
1759 if (!sifup(u))
1760 return 0;
1761 if (!sifnpmode(u, PPP_IP, NPMODE_QUEUE))
1762 return 0;
1763 if (wo->default_route)
1764 if (sifdefaultroute(u, wo->ouraddr, wo->hisaddr))
1765 default_route_set[u] = 1;
1766 if (wo->proxy_arp)
1767 if (sifproxyarp(u, wo->hisaddr))
1768 proxy_arp_set[u] = 1;
1769
1770 notice("local IP address %I", wo->ouraddr);
1771 if (wo->hisaddr)
1772 notice("remote IP address %I", wo->hisaddr);
1773
1774 return 1;
1775 }
1776
1777
1778 /*
1779 * ipcp_up - IPCP has come UP.
1780 *
1781 * Configure the IP network interface appropriately and bring it up.
1782 */
1783 static void
ipcp_up(f)1784 ipcp_up(f)
1785 fsm *f;
1786 {
1787 u_int32_t mask;
1788 ipcp_options *ho = &ipcp_hisoptions[f->unit];
1789 ipcp_options *go = &ipcp_gotoptions[f->unit];
1790 ipcp_options *wo = &ipcp_wantoptions[f->unit];
1791
1792 IPCPDEBUG(("ipcp: up"));
1793
1794 /*
1795 * We must have a non-zero IP address for both ends of the link.
1796 */
1797 if (!ho->neg_addr && !ho->old_addrs)
1798 ho->hisaddr = wo->hisaddr;
1799
1800 if (!(go->neg_addr || go->old_addrs) && (wo->neg_addr || wo->old_addrs)
1801 && wo->ouraddr != 0) {
1802 error("Peer refused to agree to our IP address");
1803 ipcp_close(f->unit, "Refused our IP address");
1804 return;
1805 }
1806 if (go->ouraddr == 0) {
1807 error("Could not determine local IP address");
1808 ipcp_close(f->unit, "Could not determine local IP address");
1809 return;
1810 }
1811 if (ho->hisaddr == 0 && !noremoteip) {
1812 ho->hisaddr = htonl(0x0a404040 + ifunit);
1813 warn("Could not determine remote IP address: defaulting to %I",
1814 ho->hisaddr);
1815 }
1816 script_setenv("IPLOCAL", ip_ntoa(go->ouraddr), 0);
1817 if (ho->hisaddr != 0)
1818 script_setenv("IPREMOTE", ip_ntoa(ho->hisaddr), 1);
1819
1820 if (!go->req_dns1)
1821 go->dnsaddr[0] = 0;
1822 if (!go->req_dns2)
1823 go->dnsaddr[1] = 0;
1824 if (go->dnsaddr[0])
1825 script_setenv("DNS1", ip_ntoa(go->dnsaddr[0]), 0);
1826 if (go->dnsaddr[1])
1827 script_setenv("DNS2", ip_ntoa(go->dnsaddr[1]), 0);
1828 if (usepeerdns && (go->dnsaddr[0] || go->dnsaddr[1])) {
1829 script_setenv("USEPEERDNS", "1", 0);
1830 create_resolv(go->dnsaddr[0], go->dnsaddr[1]);
1831 }
1832
1833 /*
1834 * Check that the peer is allowed to use the IP address it wants.
1835 */
1836 if (ho->hisaddr != 0 && !auth_ip_addr(f->unit, ho->hisaddr)) {
1837 error("Peer is not authorized to use remote address %I", ho->hisaddr);
1838 ipcp_close(f->unit, "Unauthorized remote IP address");
1839 return;
1840 }
1841
1842 /* set tcp compression */
1843 sifvjcomp(f->unit, ho->neg_vj, ho->cflag, ho->maxslotindex);
1844
1845 /*
1846 * If we are doing dial-on-demand, the interface is already
1847 * configured, so we put out any saved-up packets, then set the
1848 * interface to pass IP packets.
1849 */
1850 if (demand) {
1851 if (go->ouraddr != wo->ouraddr || ho->hisaddr != wo->hisaddr) {
1852 ipcp_clear_addrs(f->unit, wo->ouraddr, wo->hisaddr);
1853 if (go->ouraddr != wo->ouraddr) {
1854 warn("Local IP address changed to %I", go->ouraddr);
1855 script_setenv("OLDIPLOCAL", ip_ntoa(wo->ouraddr), 0);
1856 wo->ouraddr = go->ouraddr;
1857 } else
1858 script_unsetenv("OLDIPLOCAL");
1859 if (ho->hisaddr != wo->hisaddr && wo->hisaddr != 0) {
1860 warn("Remote IP address changed to %I", ho->hisaddr);
1861 script_setenv("OLDIPREMOTE", ip_ntoa(wo->hisaddr), 0);
1862 wo->hisaddr = ho->hisaddr;
1863 } else
1864 script_unsetenv("OLDIPREMOTE");
1865
1866 /* Set the interface to the new addresses */
1867 mask = GetMask(go->ouraddr);
1868 if (!sifaddr(f->unit, go->ouraddr, ho->hisaddr, mask)) {
1869 if (debug)
1870 warn("Interface configuration failed");
1871 ipcp_close(f->unit, "Interface configuration failed");
1872 return;
1873 }
1874
1875 /* assign a default route through the interface if required */
1876 if (ipcp_wantoptions[f->unit].default_route)
1877 if (sifdefaultroute(f->unit, go->ouraddr, ho->hisaddr))
1878 default_route_set[f->unit] = 1;
1879
1880 /* Make a proxy ARP entry if requested. */
1881 if (ho->hisaddr != 0 && ipcp_wantoptions[f->unit].proxy_arp)
1882 if (sifproxyarp(f->unit, ho->hisaddr))
1883 proxy_arp_set[f->unit] = 1;
1884
1885 }
1886 demand_rexmit(PPP_IP);
1887 sifnpmode(f->unit, PPP_IP, NPMODE_PASS);
1888
1889 } else {
1890 /*
1891 * Set IP addresses and (if specified) netmask.
1892 */
1893 mask = GetMask(go->ouraddr);
1894
1895 #if !(defined(SVR4) && (defined(SNI) || defined(__USLC__)))
1896 if (!sifaddr(f->unit, go->ouraddr, ho->hisaddr, mask)) {
1897 if (debug)
1898 warn("Interface configuration failed");
1899 ipcp_close(f->unit, "Interface configuration failed");
1900 return;
1901 }
1902 #endif
1903
1904 /* run the pre-up script, if any, and wait for it to finish */
1905 ipcp_script(_PATH_IPPREUP, 1);
1906
1907 /* bring the interface up for IP */
1908 if (!sifup(f->unit)) {
1909 if (debug)
1910 warn("Interface failed to come up");
1911 ipcp_close(f->unit, "Interface configuration failed");
1912 return;
1913 }
1914
1915 #if (defined(SVR4) && (defined(SNI) || defined(__USLC__)))
1916 if (!sifaddr(f->unit, go->ouraddr, ho->hisaddr, mask)) {
1917 if (debug)
1918 warn("Interface configuration failed");
1919 ipcp_close(f->unit, "Interface configuration failed");
1920 return;
1921 }
1922 #endif
1923 sifnpmode(f->unit, PPP_IP, NPMODE_PASS);
1924
1925 /* assign a default route through the interface if required */
1926 if (ipcp_wantoptions[f->unit].default_route)
1927 if (sifdefaultroute(f->unit, go->ouraddr, ho->hisaddr))
1928 default_route_set[f->unit] = 1;
1929
1930 /* Make a proxy ARP entry if requested. */
1931 if (ho->hisaddr != 0 && ipcp_wantoptions[f->unit].proxy_arp)
1932 if (sifproxyarp(f->unit, ho->hisaddr))
1933 proxy_arp_set[f->unit] = 1;
1934
1935 ipcp_wantoptions[0].ouraddr = go->ouraddr;
1936
1937 notice("local IP address %I", go->ouraddr);
1938 if (ho->hisaddr != 0)
1939 notice("remote IP address %I", ho->hisaddr);
1940 if (go->dnsaddr[0])
1941 notice("primary DNS address %I", go->dnsaddr[0]);
1942 if (go->dnsaddr[1])
1943 notice("secondary DNS address %I", go->dnsaddr[1]);
1944 }
1945
1946 reset_link_stats(f->unit);
1947
1948 np_up(f->unit, PPP_IP);
1949 ipcp_is_up = 1;
1950
1951 notify(ip_up_notifier, 0);
1952 if (ip_up_hook)
1953 ip_up_hook();
1954
1955 /*
1956 * Execute the ip-up script, like this:
1957 * /etc/ppp/ip-up interface tty speed local-IP remote-IP
1958 */
1959 if (ipcp_script_state == s_down && ipcp_script_pid == 0) {
1960 ipcp_script_state = s_up;
1961 ipcp_script(_PATH_IPUP, 0);
1962 }
1963 }
1964
1965
1966 /*
1967 * ipcp_down - IPCP has gone DOWN.
1968 *
1969 * Take the IP network interface down, clear its addresses
1970 * and delete routes through it.
1971 */
1972 static void
ipcp_down(f)1973 ipcp_down(f)
1974 fsm *f;
1975 {
1976 IPCPDEBUG(("ipcp: down"));
1977 /* XXX a bit IPv4-centric here, we only need to get the stats
1978 * before the interface is marked down. */
1979 /* XXX more correct: we must get the stats before running the notifiers,
1980 * at least for the radius plugin */
1981 update_link_stats(f->unit);
1982 notify(ip_down_notifier, 0);
1983 if (ip_down_hook)
1984 ip_down_hook();
1985 if (ipcp_is_up) {
1986 ipcp_is_up = 0;
1987 np_down(f->unit, PPP_IP);
1988 }
1989 sifvjcomp(f->unit, 0, 0, 0);
1990
1991 print_link_stats(); /* _after_ running the notifiers and ip_down_hook(),
1992 * because print_link_stats() sets link_stats_valid
1993 * to 0 (zero) */
1994
1995 /*
1996 * If we are doing dial-on-demand, set the interface
1997 * to queue up outgoing packets (for now).
1998 */
1999 if (demand) {
2000 sifnpmode(f->unit, PPP_IP, NPMODE_QUEUE);
2001 } else {
2002 sifnpmode(f->unit, PPP_IP, NPMODE_DROP);
2003 sifdown(f->unit);
2004 ipcp_clear_addrs(f->unit, ipcp_gotoptions[f->unit].ouraddr,
2005 ipcp_hisoptions[f->unit].hisaddr);
2006 }
2007
2008 /* Execute the ip-down script */
2009 if (ipcp_script_state == s_up && ipcp_script_pid == 0) {
2010 ipcp_script_state = s_down;
2011 ipcp_script(_PATH_IPDOWN, 0);
2012 }
2013 }
2014
2015
2016 /*
2017 * ipcp_clear_addrs() - clear the interface addresses, routes,
2018 * proxy arp entries, etc.
2019 */
2020 static void
ipcp_clear_addrs(unit,ouraddr,hisaddr)2021 ipcp_clear_addrs(unit, ouraddr, hisaddr)
2022 int unit;
2023 u_int32_t ouraddr; /* local address */
2024 u_int32_t hisaddr; /* remote address */
2025 {
2026 if (proxy_arp_set[unit]) {
2027 cifproxyarp(unit, hisaddr);
2028 proxy_arp_set[unit] = 0;
2029 }
2030 if (default_route_set[unit]) {
2031 cifdefaultroute(unit, ouraddr, hisaddr);
2032 default_route_set[unit] = 0;
2033 }
2034 cifaddr(unit, ouraddr, hisaddr);
2035 }
2036
2037
2038 /*
2039 * ipcp_finished - possibly shut down the lower layers.
2040 */
2041 static void
ipcp_finished(f)2042 ipcp_finished(f)
2043 fsm *f;
2044 {
2045 if (ipcp_is_open) {
2046 ipcp_is_open = 0;
2047 np_finished(f->unit, PPP_IP);
2048 }
2049 }
2050
2051
2052 /*
2053 * ipcp_script_done - called when the ip-up or ip-down script
2054 * has finished.
2055 */
2056 static void
ipcp_script_done(arg)2057 ipcp_script_done(arg)
2058 void *arg;
2059 {
2060 ipcp_script_pid = 0;
2061 switch (ipcp_script_state) {
2062 case s_up:
2063 if (ipcp_fsm[0].state != OPENED) {
2064 ipcp_script_state = s_down;
2065 ipcp_script(_PATH_IPDOWN, 0);
2066 }
2067 break;
2068 case s_down:
2069 if (ipcp_fsm[0].state == OPENED) {
2070 ipcp_script_state = s_up;
2071 ipcp_script(_PATH_IPUP, 0);
2072 }
2073 break;
2074 }
2075 }
2076
2077
2078 /*
2079 * ipcp_script - Execute a script with arguments
2080 * interface-name tty-name speed local-IP remote-IP.
2081 */
2082 static void
ipcp_script(script,wait)2083 ipcp_script(script, wait)
2084 char *script;
2085 int wait;
2086 {
2087 char strspeed[32], strlocal[32], strremote[32];
2088 char *argv[8];
2089
2090 slprintf(strspeed, sizeof(strspeed), "%d", baud_rate);
2091 slprintf(strlocal, sizeof(strlocal), "%I", ipcp_gotoptions[0].ouraddr);
2092 slprintf(strremote, sizeof(strremote), "%I", ipcp_hisoptions[0].hisaddr);
2093
2094 argv[0] = script;
2095 argv[1] = ifname;
2096 argv[2] = devnam;
2097 argv[3] = strspeed;
2098 argv[4] = strlocal;
2099 argv[5] = strremote;
2100 argv[6] = ipparam;
2101 argv[7] = NULL;
2102 if (wait)
2103 run_program(script, argv, 0, NULL, NULL, 1);
2104 else
2105 ipcp_script_pid = run_program(script, argv, 0, ipcp_script_done,
2106 NULL, 0);
2107 }
2108
2109 /*
2110 * create_resolv - create the replacement resolv.conf file
2111 */
2112 static void
create_resolv(peerdns1,peerdns2)2113 create_resolv(peerdns1, peerdns2)
2114 u_int32_t peerdns1, peerdns2;
2115 {
2116 #if !defined(__ANDROID__)
2117 FILE *f;
2118
2119 f = fopen(_PATH_RESOLV, "w");
2120 if (f == NULL) {
2121 error("Failed to create %s: %m", _PATH_RESOLV);
2122 return;
2123 }
2124
2125 if (peerdns1)
2126 fprintf(f, "nameserver %s\n", ip_ntoa(peerdns1));
2127
2128 if (peerdns2)
2129 fprintf(f, "nameserver %s\n", ip_ntoa(peerdns2));
2130
2131 if (ferror(f))
2132 error("Write failed to %s: %m", _PATH_RESOLV);
2133
2134 fclose(f);
2135 #endif
2136 }
2137
2138 /*
2139 * ipcp_printpkt - print the contents of an IPCP packet.
2140 */
2141 static char *ipcp_codenames[] = {
2142 "ConfReq", "ConfAck", "ConfNak", "ConfRej",
2143 "TermReq", "TermAck", "CodeRej"
2144 };
2145
2146 static int
ipcp_printpkt(p,plen,printer,arg)2147 ipcp_printpkt(p, plen, printer, arg)
2148 u_char *p;
2149 int plen;
2150 void (*printer) __P((void *, char *, ...));
2151 void *arg;
2152 {
2153 int code, id, len, olen;
2154 u_char *pstart, *optend;
2155 u_short cishort;
2156 u_int32_t cilong;
2157
2158 if (plen < HEADERLEN)
2159 return 0;
2160 pstart = p;
2161 GETCHAR(code, p);
2162 GETCHAR(id, p);
2163 GETSHORT(len, p);
2164 if (len < HEADERLEN || len > plen)
2165 return 0;
2166
2167 if (code >= 1 && code <= sizeof(ipcp_codenames) / sizeof(char *))
2168 printer(arg, " %s", ipcp_codenames[code-1]);
2169 else
2170 printer(arg, " code=0x%x", code);
2171 printer(arg, " id=0x%x", id);
2172 len -= HEADERLEN;
2173 switch (code) {
2174 case CONFREQ:
2175 case CONFACK:
2176 case CONFNAK:
2177 case CONFREJ:
2178 /* print option list */
2179 while (len >= 2) {
2180 GETCHAR(code, p);
2181 GETCHAR(olen, p);
2182 p -= 2;
2183 if (olen < 2 || olen > len) {
2184 break;
2185 }
2186 printer(arg, " <");
2187 len -= olen;
2188 optend = p + olen;
2189 switch (code) {
2190 case CI_ADDRS:
2191 if (olen == CILEN_ADDRS) {
2192 p += 2;
2193 GETLONG(cilong, p);
2194 printer(arg, "addrs %I", htonl(cilong));
2195 GETLONG(cilong, p);
2196 printer(arg, " %I", htonl(cilong));
2197 }
2198 break;
2199 case CI_COMPRESSTYPE:
2200 if (olen >= CILEN_COMPRESS) {
2201 p += 2;
2202 GETSHORT(cishort, p);
2203 printer(arg, "compress ");
2204 switch (cishort) {
2205 case IPCP_VJ_COMP:
2206 printer(arg, "VJ");
2207 break;
2208 case IPCP_VJ_COMP_OLD:
2209 printer(arg, "old-VJ");
2210 break;
2211 default:
2212 printer(arg, "0x%x", cishort);
2213 }
2214 }
2215 break;
2216 case CI_ADDR:
2217 if (olen == CILEN_ADDR) {
2218 p += 2;
2219 GETLONG(cilong, p);
2220 printer(arg, "addr %I", htonl(cilong));
2221 }
2222 break;
2223 case CI_MS_DNS1:
2224 case CI_MS_DNS2:
2225 p += 2;
2226 GETLONG(cilong, p);
2227 printer(arg, "ms-dns%d %I", (code == CI_MS_DNS1? 1: 2),
2228 htonl(cilong));
2229 break;
2230 case CI_MS_WINS1:
2231 case CI_MS_WINS2:
2232 p += 2;
2233 GETLONG(cilong, p);
2234 printer(arg, "ms-wins %I", htonl(cilong));
2235 break;
2236 }
2237 while (p < optend) {
2238 GETCHAR(code, p);
2239 printer(arg, " %.2x", code);
2240 }
2241 printer(arg, ">");
2242 }
2243 break;
2244
2245 case TERMACK:
2246 case TERMREQ:
2247 if (len > 0 && *p >= ' ' && *p < 0x7f) {
2248 printer(arg, " ");
2249 print_string((char *)p, len, printer, arg);
2250 p += len;
2251 len = 0;
2252 }
2253 break;
2254 }
2255
2256 /* print the rest of the bytes in the packet */
2257 for (; len > 0; --len) {
2258 GETCHAR(code, p);
2259 printer(arg, " %.2x", code);
2260 }
2261
2262 return p - pstart;
2263 }
2264
2265 /*
2266 * ip_active_pkt - see if this IP packet is worth bringing the link up for.
2267 * We don't bring the link up for IP fragments or for TCP FIN packets
2268 * with no data.
2269 */
2270 #define IP_HDRLEN 20 /* bytes */
2271 #define IP_OFFMASK 0x1fff
2272 #ifndef IPPROTO_TCP
2273 #define IPPROTO_TCP 6
2274 #endif
2275 #define TCP_HDRLEN 20
2276 #define TH_FIN 0x01
2277
2278 /*
2279 * We use these macros because the IP header may be at an odd address,
2280 * and some compilers might use word loads to get th_off or ip_hl.
2281 */
2282
2283 #define net_short(x) (((x)[0] << 8) + (x)[1])
2284 #define get_iphl(x) (((unsigned char *)(x))[0] & 0xF)
2285 #define get_ipoff(x) net_short((unsigned char *)(x) + 6)
2286 #define get_ipproto(x) (((unsigned char *)(x))[9])
2287 #define get_tcpoff(x) (((unsigned char *)(x))[12] >> 4)
2288 #define get_tcpflags(x) (((unsigned char *)(x))[13])
2289
2290 static int
ip_active_pkt(pkt,len)2291 ip_active_pkt(pkt, len)
2292 u_char *pkt;
2293 int len;
2294 {
2295 u_char *tcp;
2296 int hlen;
2297
2298 len -= PPP_HDRLEN;
2299 pkt += PPP_HDRLEN;
2300 if (len < IP_HDRLEN)
2301 return 0;
2302 if ((get_ipoff(pkt) & IP_OFFMASK) != 0)
2303 return 0;
2304 if (get_ipproto(pkt) != IPPROTO_TCP)
2305 return 1;
2306 hlen = get_iphl(pkt) * 4;
2307 if (len < hlen + TCP_HDRLEN)
2308 return 0;
2309 tcp = pkt + hlen;
2310 if ((get_tcpflags(tcp) & TH_FIN) != 0 && len == hlen + get_tcpoff(tcp) * 4)
2311 return 0;
2312 return 1;
2313 }
2314