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1 /*
2  * auth.c - PPP authentication and phase control.
3  *
4  * Copyright (c) 1993-2002 Paul Mackerras. 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. The name(s) of the authors of this software must not be used to
14  *    endorse or promote products derived from this software without
15  *    prior written permission.
16  *
17  * 3. Redistributions of any form whatsoever must retain the following
18  *    acknowledgment:
19  *    "This product includes software developed by Paul Mackerras
20  *     <paulus@samba.org>".
21  *
22  * THE AUTHORS OF THIS SOFTWARE DISCLAIM ALL WARRANTIES WITH REGARD TO
23  * THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
24  * AND FITNESS, IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY
25  * SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
26  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN
27  * AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING
28  * OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
29  *
30  * Derived from main.c, which is:
31  *
32  * Copyright (c) 1984-2000 Carnegie Mellon University. All rights reserved.
33  *
34  * Redistribution and use in source and binary forms, with or without
35  * modification, are permitted provided that the following conditions
36  * are met:
37  *
38  * 1. Redistributions of source code must retain the above copyright
39  *    notice, this list of conditions and the following disclaimer.
40  *
41  * 2. Redistributions in binary form must reproduce the above copyright
42  *    notice, this list of conditions and the following disclaimer in
43  *    the documentation and/or other materials provided with the
44  *    distribution.
45  *
46  * 3. The name "Carnegie Mellon University" must not be used to
47  *    endorse or promote products derived from this software without
48  *    prior written permission. For permission or any legal
49  *    details, please contact
50  *      Office of Technology Transfer
51  *      Carnegie Mellon University
52  *      5000 Forbes Avenue
53  *      Pittsburgh, PA  15213-3890
54  *      (412) 268-4387, fax: (412) 268-7395
55  *      tech-transfer@andrew.cmu.edu
56  *
57  * 4. Redistributions of any form whatsoever must retain the following
58  *    acknowledgment:
59  *    "This product includes software developed by Computing Services
60  *     at Carnegie Mellon University (http://www.cmu.edu/computing/)."
61  *
62  * CARNEGIE MELLON UNIVERSITY DISCLAIMS ALL WARRANTIES WITH REGARD TO
63  * THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
64  * AND FITNESS, IN NO EVENT SHALL CARNEGIE MELLON UNIVERSITY BE LIABLE
65  * FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
66  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN
67  * AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING
68  * OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
69  */
70 
71 #include "netif/ppp/ppp_opts.h"
72 #if PPP_SUPPORT /* don't build if not configured for use in lwipopts.h */
73 
74 #if 0 /* UNUSED */
75 #include <stdio.h>
76 #include <stddef.h>
77 #include <stdlib.h>
78 #include <unistd.h>
79 #include <errno.h>
80 #include <pwd.h>
81 #include <grp.h>
82 #include <string.h>
83 #include <sys/types.h>
84 #include <sys/stat.h>
85 #include <sys/socket.h>
86 #include <utmp.h>
87 #include <fcntl.h>
88 #if defined(_PATH_LASTLOG) && defined(__linux__)
89 #include <lastlog.h>
90 #endif
91 
92 #include <netdb.h>
93 #include <netinet/in.h>
94 #include <arpa/inet.h>
95 
96 #ifdef HAS_SHADOW
97 #include <shadow.h>
98 #ifndef PW_PPP
99 #define PW_PPP PW_LOGIN
100 #endif
101 #endif
102 
103 #include <time.h>
104 #endif /* UNUSED */
105 
106 #include "netif/ppp/ppp_impl.h"
107 
108 #include "netif/ppp/fsm.h"
109 #include "netif/ppp/lcp.h"
110 #if CCP_SUPPORT
111 #include "netif/ppp/ccp.h"
112 #endif /* CCP_SUPPORT */
113 #if ECP_SUPPORT
114 #include "netif/ppp/ecp.h"
115 #endif /* ECP_SUPPORT */
116 #include "netif/ppp/ipcp.h"
117 #if PAP_SUPPORT
118 #include "netif/ppp/upap.h"
119 #endif /* PAP_SUPPORT */
120 #if CHAP_SUPPORT
121 #include "netif/ppp/chap-new.h"
122 #endif /* CHAP_SUPPORT */
123 #if EAP_SUPPORT
124 #include "netif/ppp/eap.h"
125 #endif /* EAP_SUPPORT */
126 #if CBCP_SUPPORT
127 #include "netif/ppp/cbcp.h"
128 #endif
129 
130 #if 0 /* UNUSED */
131 #include "session.h"
132 #endif /* UNUSED */
133 
134 #if 0 /* UNUSED */
135 /* Bits in scan_authfile return value */
136 #define NONWILD_SERVER	1
137 #define NONWILD_CLIENT	2
138 
139 #define ISWILD(word)	(word[0] == '*' && word[1] == 0)
140 #endif /* UNUSED */
141 
142 #if 0 /* UNUSED */
143 /* List of addresses which the peer may use. */
144 static struct permitted_ip *addresses[NUM_PPP];
145 
146 /* Wordlist giving addresses which the peer may use
147    without authenticating itself. */
148 static struct wordlist *noauth_addrs;
149 
150 /* Remote telephone number, if available */
151 char remote_number[MAXNAMELEN];
152 
153 /* Wordlist giving remote telephone numbers which may connect. */
154 static struct wordlist *permitted_numbers;
155 
156 /* Extra options to apply, from the secrets file entry for the peer. */
157 static struct wordlist *extra_options;
158 #endif /* UNUSED */
159 
160 #if 0 /* UNUSED */
161 /* Set if we require authentication only because we have a default route. */
162 static bool default_auth;
163 
164 /* Hook to enable a plugin to control the idle time limit */
165 int (*idle_time_hook) (struct ppp_idle *) = NULL;
166 
167 /* Hook for a plugin to say whether we can possibly authenticate any peer */
168 int (*pap_check_hook) (void) = NULL;
169 
170 /* Hook for a plugin to check the PAP user and password */
171 int (*pap_auth_hook) (char *user, char *passwd, char **msgp,
172 			  struct wordlist **paddrs,
173 			  struct wordlist **popts) = NULL;
174 
175 /* Hook for a plugin to know about the PAP user logout */
176 void (*pap_logout_hook) (void) = NULL;
177 
178 /* Hook for a plugin to get the PAP password for authenticating us */
179 int (*pap_passwd_hook) (char *user, char *passwd) = NULL;
180 
181 /* Hook for a plugin to say if we can possibly authenticate a peer using CHAP */
182 int (*chap_check_hook) (void) = NULL;
183 
184 /* Hook for a plugin to get the CHAP password for authenticating us */
185 int (*chap_passwd_hook) (char *user, char *passwd) = NULL;
186 
187 /* Hook for a plugin to say whether it is OK if the peer
188    refuses to authenticate. */
189 int (*null_auth_hook) (struct wordlist **paddrs,
190 			   struct wordlist **popts) = NULL;
191 
192 int (*allowed_address_hook) (u32_t addr) = NULL;
193 #endif /* UNUSED */
194 
195 #ifdef HAVE_MULTILINK
196 /* Hook for plugin to hear when an interface joins a multilink bundle */
197 void (*multilink_join_hook) (void) = NULL;
198 #endif
199 
200 #if PPP_NOTIFY
201 /* A notifier for when the peer has authenticated itself,
202    and we are proceeding to the network phase. */
203 struct notifier *auth_up_notifier = NULL;
204 
205 /* A notifier for when the link goes down. */
206 struct notifier *link_down_notifier = NULL;
207 #endif /* PPP_NOTIFY */
208 
209 /*
210  * Option variables.
211  */
212 #if 0 /* MOVED TO ppp_settings */
213 bool uselogin = 0;		/* Use /etc/passwd for checking PAP */
214 bool session_mgmt = 0;		/* Do session management (login records) */
215 bool cryptpap = 0;		/* Passwords in pap-secrets are encrypted */
216 bool refuse_pap = 0;		/* Don't wanna auth. ourselves with PAP */
217 bool refuse_chap = 0;		/* Don't wanna auth. ourselves with CHAP */
218 bool refuse_eap = 0;		/* Don't wanna auth. ourselves with EAP */
219 #if MSCHAP_SUPPORT
220 bool refuse_mschap = 0;		/* Don't wanna auth. ourselves with MS-CHAP */
221 bool refuse_mschap_v2 = 0;	/* Don't wanna auth. ourselves with MS-CHAPv2 */
222 #else /* MSCHAP_SUPPORT */
223 bool refuse_mschap = 1;		/* Don't wanna auth. ourselves with MS-CHAP */
224 bool refuse_mschap_v2 = 1;	/* Don't wanna auth. ourselves with MS-CHAPv2 */
225 #endif /* MSCHAP_SUPPORT */
226 bool usehostname = 0;		/* Use hostname for our_name */
227 bool auth_required = 0;		/* Always require authentication from peer */
228 bool allow_any_ip = 0;		/* Allow peer to use any IP address */
229 bool explicit_remote = 0;	/* User specified explicit remote name */
230 bool explicit_user = 0;		/* Set if "user" option supplied */
231 bool explicit_passwd = 0;	/* Set if "password" option supplied */
232 char remote_name[MAXNAMELEN];	/* Peer's name for authentication */
233 static char *uafname;		/* name of most recent +ua file */
234 
235 extern char *crypt (const char *, const char *);
236 #endif /* UNUSED */
237 /* Prototypes for procedures local to this file. */
238 
239 static void network_phase(ppp_pcb *pcb);
240 #if PPP_IDLETIMELIMIT
241 static void check_idle(void *arg);
242 #endif /* PPP_IDLETIMELIMIT */
243 #if PPP_MAXCONNECT
244 static void connect_time_expired(void *arg);
245 #endif /* PPP_MAXCONNECT */
246 #if 0 /* UNUSED */
247 static int  null_login (int);
248 /* static int  get_pap_passwd (char *); */
249 static int  have_pap_secret (int *);
250 static int  have_chap_secret (char *, char *, int, int *);
251 static int  have_srp_secret (char *client, char *server, int need_ip,
252     int *lacks_ipp);
253 static int  ip_addr_check (u32_t, struct permitted_ip *);
254 static int  scan_authfile (FILE *, char *, char *, char *,
255 			       struct wordlist **, struct wordlist **,
256 			       char *, int);
257 static void free_wordlist (struct wordlist *);
258 static void set_allowed_addrs (int, struct wordlist *, struct wordlist *);
259 static int  some_ip_ok (struct wordlist *);
260 static int  setupapfile (char **);
261 static int  privgroup (char **);
262 static int  set_noauth_addr (char **);
263 static int  set_permitted_number (char **);
264 static void check_access (FILE *, char *);
265 static int  wordlist_count (struct wordlist *);
266 #endif /* UNUSED */
267 
268 #ifdef MAXOCTETS
269 static void check_maxoctets (void *);
270 #endif
271 
272 #if PPP_OPTIONS
273 /*
274  * Authentication-related options.
275  */
276 option_t auth_options[] = {
277     { "auth", o_bool, &auth_required,
278       "Require authentication from peer", OPT_PRIO | 1 },
279     { "noauth", o_bool, &auth_required,
280       "Don't require peer to authenticate", OPT_PRIOSUB | OPT_PRIV,
281       &allow_any_ip },
282     { "require-pap", o_bool, &lcp_wantoptions[0].neg_upap,
283       "Require PAP authentication from peer",
284       OPT_PRIOSUB | 1, &auth_required },
285     { "+pap", o_bool, &lcp_wantoptions[0].neg_upap,
286       "Require PAP authentication from peer",
287       OPT_ALIAS | OPT_PRIOSUB | 1, &auth_required },
288     { "require-chap", o_bool, &auth_required,
289       "Require CHAP authentication from peer",
290       OPT_PRIOSUB | OPT_A2OR | MDTYPE_MD5,
291       &lcp_wantoptions[0].chap_mdtype },
292     { "+chap", o_bool, &auth_required,
293       "Require CHAP authentication from peer",
294       OPT_ALIAS | OPT_PRIOSUB | OPT_A2OR | MDTYPE_MD5,
295       &lcp_wantoptions[0].chap_mdtype },
296 #if MSCHAP_SUPPORT
297     { "require-mschap", o_bool, &auth_required,
298       "Require MS-CHAP authentication from peer",
299       OPT_PRIOSUB | OPT_A2OR | MDTYPE_MICROSOFT,
300       &lcp_wantoptions[0].chap_mdtype },
301     { "+mschap", o_bool, &auth_required,
302       "Require MS-CHAP authentication from peer",
303       OPT_ALIAS | OPT_PRIOSUB | OPT_A2OR | MDTYPE_MICROSOFT,
304       &lcp_wantoptions[0].chap_mdtype },
305     { "require-mschap-v2", o_bool, &auth_required,
306       "Require MS-CHAPv2 authentication from peer",
307       OPT_PRIOSUB | OPT_A2OR | MDTYPE_MICROSOFT_V2,
308       &lcp_wantoptions[0].chap_mdtype },
309     { "+mschap-v2", o_bool, &auth_required,
310       "Require MS-CHAPv2 authentication from peer",
311       OPT_ALIAS | OPT_PRIOSUB | OPT_A2OR | MDTYPE_MICROSOFT_V2,
312       &lcp_wantoptions[0].chap_mdtype },
313 #endif /* MSCHAP_SUPPORT */
314 #if 0
315     { "refuse-pap", o_bool, &refuse_pap,
316       "Don't agree to auth to peer with PAP", 1 },
317     { "-pap", o_bool, &refuse_pap,
318       "Don't allow PAP authentication with peer", OPT_ALIAS | 1 },
319     { "refuse-chap", o_bool, &refuse_chap,
320       "Don't agree to auth to peer with CHAP",
321       OPT_A2CLRB | MDTYPE_MD5,
322       &lcp_allowoptions[0].chap_mdtype },
323     { "-chap", o_bool, &refuse_chap,
324       "Don't allow CHAP authentication with peer",
325       OPT_ALIAS | OPT_A2CLRB | MDTYPE_MD5,
326       &lcp_allowoptions[0].chap_mdtype },
327 #endif
328 #if MSCHAP_SUPPORT
329 #if 0
330     { "refuse-mschap", o_bool, &refuse_mschap,
331       "Don't agree to auth to peer with MS-CHAP",
332       OPT_A2CLRB | MDTYPE_MICROSOFT,
333       &lcp_allowoptions[0].chap_mdtype },
334     { "-mschap", o_bool, &refuse_mschap,
335       "Don't allow MS-CHAP authentication with peer",
336       OPT_ALIAS | OPT_A2CLRB | MDTYPE_MICROSOFT,
337       &lcp_allowoptions[0].chap_mdtype },
338     { "refuse-mschap-v2", o_bool, &refuse_mschap_v2,
339       "Don't agree to auth to peer with MS-CHAPv2",
340       OPT_A2CLRB | MDTYPE_MICROSOFT_V2,
341       &lcp_allowoptions[0].chap_mdtype },
342     { "-mschap-v2", o_bool, &refuse_mschap_v2,
343       "Don't allow MS-CHAPv2 authentication with peer",
344       OPT_ALIAS | OPT_A2CLRB | MDTYPE_MICROSOFT_V2,
345       &lcp_allowoptions[0].chap_mdtype },
346 #endif
347 #endif /* MSCHAP_SUPPORT*/
348 #if EAP_SUPPORT
349     { "require-eap", o_bool, &lcp_wantoptions[0].neg_eap,
350       "Require EAP authentication from peer", OPT_PRIOSUB | 1,
351       &auth_required },
352 #if 0
353     { "refuse-eap", o_bool, &refuse_eap,
354       "Don't agree to authenticate to peer with EAP", 1 },
355 #endif
356 #endif /* EAP_SUPPORT */
357     { "name", o_string, our_name,
358       "Set local name for authentication",
359       OPT_PRIO | OPT_PRIV | OPT_STATIC, NULL, MAXNAMELEN },
360 
361     { "+ua", o_special, (void *)setupapfile,
362       "Get PAP user and password from file",
363       OPT_PRIO | OPT_A2STRVAL, &uafname },
364 
365 #if 0
366     { "user", o_string, user,
367       "Set name for auth with peer", OPT_PRIO | OPT_STATIC,
368       &explicit_user, MAXNAMELEN },
369 
370     { "password", o_string, passwd,
371       "Password for authenticating us to the peer",
372       OPT_PRIO | OPT_STATIC | OPT_HIDE,
373       &explicit_passwd, MAXSECRETLEN },
374 #endif
375 
376     { "usehostname", o_bool, &usehostname,
377       "Must use hostname for authentication", 1 },
378 
379     { "remotename", o_string, remote_name,
380       "Set remote name for authentication", OPT_PRIO | OPT_STATIC,
381       &explicit_remote, MAXNAMELEN },
382 
383     { "login", o_bool, &uselogin,
384       "Use system password database for PAP", OPT_A2COPY | 1 ,
385       &session_mgmt },
386     { "enable-session", o_bool, &session_mgmt,
387       "Enable session accounting for remote peers", OPT_PRIV | 1 },
388 
389     { "papcrypt", o_bool, &cryptpap,
390       "PAP passwords are encrypted", 1 },
391 
392     { "privgroup", o_special, (void *)privgroup,
393       "Allow group members to use privileged options", OPT_PRIV | OPT_A2LIST },
394 
395     { "allow-ip", o_special, (void *)set_noauth_addr,
396       "Set IP address(es) which can be used without authentication",
397       OPT_PRIV | OPT_A2LIST },
398 
399     { "remotenumber", o_string, remote_number,
400       "Set remote telephone number for authentication", OPT_PRIO | OPT_STATIC,
401       NULL, MAXNAMELEN },
402 
403     { "allow-number", o_special, (void *)set_permitted_number,
404       "Set telephone number(s) which are allowed to connect",
405       OPT_PRIV | OPT_A2LIST },
406 
407     { NULL }
408 };
409 #endif /* PPP_OPTIONS */
410 
411 #if 0 /* UNUSED */
412 /*
413  * setupapfile - specifies UPAP info for authenticating with peer.
414  */
415 static int
416 setupapfile(argv)
417     char **argv;
418 {
419     FILE *ufile;
420     int l;
421     uid_t euid;
422     char u[MAXNAMELEN], p[MAXSECRETLEN];
423     char *fname;
424 
425     lcp_allowoptions[0].neg_upap = 1;
426 
427     /* open user info file */
428     fname = strdup(*argv);
429     if (fname == NULL)
430 	novm("+ua file name");
431     euid = geteuid();
432     if (seteuid(getuid()) == -1) {
433 	option_error("unable to reset uid before opening %s: %m", fname);
434 	return 0;
435     }
436     ufile = fopen(fname, "r");
437     if (seteuid(euid) == -1)
438 	fatal("unable to regain privileges: %m");
439     if (ufile == NULL) {
440 	option_error("unable to open user login data file %s", fname);
441 	return 0;
442     }
443     check_access(ufile, fname);
444     uafname = fname;
445 
446     /* get username */
447     if (fgets(u, MAXNAMELEN - 1, ufile) == NULL
448 	|| fgets(p, MAXSECRETLEN - 1, ufile) == NULL) {
449 	fclose(ufile);
450 	option_error("unable to read user login data file %s", fname);
451 	return 0;
452     }
453     fclose(ufile);
454 
455     /* get rid of newlines */
456     l = strlen(u);
457     if (l > 0 && u[l-1] == '\n')
458 	u[l-1] = 0;
459     l = strlen(p);
460     if (l > 0 && p[l-1] == '\n')
461 	p[l-1] = 0;
462 
463     if (override_value("user", option_priority, fname)) {
464 	strlcpy(ppp_settings.user, u, sizeof(ppp_settings.user));
465 	explicit_user = 1;
466     }
467     if (override_value("passwd", option_priority, fname)) {
468 	strlcpy(ppp_settings.passwd, p, sizeof(ppp_settings.passwd));
469 	explicit_passwd = 1;
470     }
471 
472     return (1);
473 }
474 
475 /*
476  * privgroup - allow members of the group to have privileged access.
477  */
478 static int
479 privgroup(argv)
480     char **argv;
481 {
482     struct group *g;
483     int i;
484 
485     g = getgrnam(*argv);
486     if (g == 0) {
487 	option_error("group %s is unknown", *argv);
488 	return 0;
489     }
490     for (i = 0; i < ngroups; ++i) {
491 	if (groups[i] == g->gr_gid) {
492 	    privileged = 1;
493 	    break;
494 	}
495     }
496     return 1;
497 }
498 
499 
500 /*
501  * set_noauth_addr - set address(es) that can be used without authentication.
502  * Equivalent to specifying an entry like `"" * "" addr' in pap-secrets.
503  */
504 static int
505 set_noauth_addr(argv)
506     char **argv;
507 {
508     char *addr = *argv;
509     int l = strlen(addr) + 1;
510     struct wordlist *wp;
511 
512     wp = (struct wordlist *) malloc(sizeof(struct wordlist) + l);
513     if (wp == NULL)
514 	novm("allow-ip argument");
515     wp->word = (char *) (wp + 1);
516     wp->next = noauth_addrs;
517     MEMCPY(wp->word, addr, l);
518     noauth_addrs = wp;
519     return 1;
520 }
521 
522 
523 /*
524  * set_permitted_number - set remote telephone number(s) that may connect.
525  */
526 static int
527 set_permitted_number(argv)
528     char **argv;
529 {
530     char *number = *argv;
531     int l = strlen(number) + 1;
532     struct wordlist *wp;
533 
534     wp = (struct wordlist *) malloc(sizeof(struct wordlist) + l);
535     if (wp == NULL)
536 	novm("allow-number argument");
537     wp->word = (char *) (wp + 1);
538     wp->next = permitted_numbers;
539     MEMCPY(wp->word, number, l);
540     permitted_numbers = wp;
541     return 1;
542 }
543 #endif
544 
545 /*
546  * An Open on LCP has requested a change from Dead to Establish phase.
547  */
link_required(ppp_pcb * pcb)548 void link_required(ppp_pcb *pcb) {
549     LWIP_UNUSED_ARG(pcb);
550 }
551 
552 #if 0
553 /*
554  * Bring the link up to the point of being able to do ppp.
555  */
556 void start_link(unit)
557     int unit;
558 {
559     ppp_pcb *pcb = &ppp_pcb_list[unit];
560     char *msg;
561 
562     status = EXIT_NEGOTIATION_FAILED;
563     new_phase(pcb, PPP_PHASE_SERIALCONN);
564 
565     hungup = 0;
566     devfd = the_channel->connect();
567     msg = "Connect script failed";
568     if (devfd < 0)
569 	goto fail;
570 
571     /* set up the serial device as a ppp interface */
572     /*
573      * N.B. we used to do tdb_writelock/tdb_writeunlock around this
574      * (from establish_ppp to set_ifunit).  However, we won't be
575      * doing the set_ifunit in multilink mode, which is the only time
576      * we need the atomicity that the tdb_writelock/tdb_writeunlock
577      * gives us.  Thus we don't need the tdb_writelock/tdb_writeunlock.
578      */
579     fd_ppp = the_channel->establish_ppp(devfd);
580     msg = "ppp establishment failed";
581     if (fd_ppp < 0) {
582 	status = EXIT_FATAL_ERROR;
583 	goto disconnect;
584     }
585 
586     if (!demand && ifunit >= 0)
587 	set_ifunit(1);
588 
589     /*
590      * Start opening the connection and wait for
591      * incoming events (reply, timeout, etc.).
592      */
593     if (ifunit >= 0)
594 	ppp_notice("Connect: %s <--> %s", ifname, ppp_devnam);
595     else
596 	ppp_notice("Starting negotiation on %s", ppp_devnam);
597     add_fd(fd_ppp);
598 
599     new_phase(pcb, PPP_PHASE_ESTABLISH);
600 
601     lcp_lowerup(pcb);
602     return;
603 
604  disconnect:
605     new_phase(pcb, PPP_PHASE_DISCONNECT);
606     if (the_channel->disconnect)
607 	the_channel->disconnect();
608 
609  fail:
610     new_phase(pcb, PPP_PHASE_DEAD);
611     if (the_channel->cleanup)
612 	(*the_channel->cleanup)();
613 }
614 #endif
615 
616 /*
617  * LCP has terminated the link; go to the Dead phase and take the
618  * physical layer down.
619  */
link_terminated(ppp_pcb * pcb)620 void link_terminated(ppp_pcb *pcb) {
621     if (pcb->phase == PPP_PHASE_DEAD
622 #ifdef HAVE_MULTILINK
623     || pcb->phase == PPP_PHASE_MASTER
624 #endif /* HAVE_MULTILINK */
625     )
626 	return;
627     new_phase(pcb, PPP_PHASE_DISCONNECT);
628 
629 #if 0 /* UNUSED */
630     if (pap_logout_hook) {
631 	pap_logout_hook();
632     }
633     session_end(devnam);
634 #endif /* UNUSED */
635 
636     if (!doing_multilink) {
637 	ppp_notice("Connection terminated.");
638 #if PPP_STATS_SUPPORT
639 	print_link_stats();
640 #endif /* PPP_STATS_SUPPORT */
641     } else
642 	ppp_notice("Link terminated.");
643 
644     lcp_lowerdown(pcb);
645 
646     ppp_link_terminated(pcb);
647 #if 0
648     /*
649      * Delete pid files before disestablishing ppp.  Otherwise it
650      * can happen that another pppd gets the same unit and then
651      * we delete its pid file.
652      */
653     if (!doing_multilink && !demand)
654 	remove_pidfiles();
655 
656     /*
657      * If we may want to bring the link up again, transfer
658      * the ppp unit back to the loopback.  Set the
659      * real serial device back to its normal mode of operation.
660      */
661     if (fd_ppp >= 0) {
662 	remove_fd(fd_ppp);
663 	clean_check();
664 	the_channel->disestablish_ppp(devfd);
665 	if (doing_multilink)
666 	    mp_exit_bundle();
667 	fd_ppp = -1;
668     }
669     if (!hungup)
670 	lcp_lowerdown(pcb);
671     if (!doing_multilink && !demand)
672 	script_unsetenv("IFNAME");
673 
674     /*
675      * Run disconnector script, if requested.
676      * XXX we may not be able to do this if the line has hung up!
677      */
678     if (devfd >= 0 && the_channel->disconnect) {
679 	the_channel->disconnect();
680 	devfd = -1;
681     }
682     if (the_channel->cleanup)
683 	(*the_channel->cleanup)();
684 
685     if (doing_multilink && multilink_master) {
686 	if (!bundle_terminating)
687 	    new_phase(pcb, PPP_PHASE_MASTER);
688 	else
689 	    mp_bundle_terminated();
690     } else
691 	new_phase(pcb, PPP_PHASE_DEAD);
692 #endif
693 }
694 
695 /*
696  * LCP has gone down; it will either die or try to re-establish.
697  */
link_down(ppp_pcb * pcb)698 void link_down(ppp_pcb *pcb) {
699 #if PPP_NOTIFY
700     notify(link_down_notifier, 0);
701 #endif /* PPP_NOTIFY */
702 
703     if (!doing_multilink) {
704 	upper_layers_down(pcb);
705 	if (pcb->phase != PPP_PHASE_DEAD
706 #ifdef HAVE_MULTILINK
707 	&& pcb->phase != PPP_PHASE_MASTER
708 #endif /* HAVE_MULTILINK */
709 	)
710 	    new_phase(pcb, PPP_PHASE_ESTABLISH);
711     }
712     /* XXX if doing_multilink, should do something to stop
713        network-layer traffic on the link */
714 }
715 
upper_layers_down(ppp_pcb * pcb)716 void upper_layers_down(ppp_pcb *pcb) {
717     int i;
718     const struct protent *protp;
719 
720     for (i = 0; (protp = protocols[i]) != NULL; ++i) {
721         if (protp->protocol != PPP_LCP && protp->lowerdown != NULL)
722 	    (*protp->lowerdown)(pcb);
723         if (protp->protocol < 0xC000 && protp->close != NULL)
724 	    (*protp->close)(pcb, "LCP down");
725     }
726     pcb->num_np_open = 0;
727     pcb->num_np_up = 0;
728 }
729 
730 /*
731  * The link is established.
732  * Proceed to the Dead, Authenticate or Network phase as appropriate.
733  */
link_established(ppp_pcb * pcb)734 void link_established(ppp_pcb *pcb) {
735 #if PPP_AUTH_SUPPORT
736     int auth;
737 #if PPP_SERVER
738 #if PAP_SUPPORT
739     lcp_options *wo = &pcb->lcp_wantoptions;
740 #endif /* PAP_SUPPORT */
741     lcp_options *go = &pcb->lcp_gotoptions;
742 #endif /* PPP_SERVER */
743     lcp_options *ho = &pcb->lcp_hisoptions;
744 #endif /* PPP_AUTH_SUPPORT */
745     int i;
746     const struct protent *protp;
747 
748     /*
749      * Tell higher-level protocols that LCP is up.
750      */
751     if (!doing_multilink) {
752 	for (i = 0; (protp = protocols[i]) != NULL; ++i)
753 	    if (protp->protocol != PPP_LCP
754 		&& protp->lowerup != NULL)
755 		(*protp->lowerup)(pcb);
756     }
757 
758 #if PPP_AUTH_SUPPORT
759 #if PPP_SERVER
760 #if PPP_ALLOWED_ADDRS
761     if (!auth_required && noauth_addrs != NULL)
762 	set_allowed_addrs(unit, NULL, NULL);
763 #endif /* PPP_ALLOWED_ADDRS */
764 
765     if (pcb->settings.auth_required && !(0
766 #if PAP_SUPPORT
767 	|| go->neg_upap
768 #endif /* PAP_SUPPORT */
769 #if CHAP_SUPPORT
770 	|| go->neg_chap
771 #endif /* CHAP_SUPPORT */
772 #if EAP_SUPPORT
773 	|| go->neg_eap
774 #endif /* EAP_SUPPORT */
775 	)) {
776 
777 #if PPP_ALLOWED_ADDRS
778 	/*
779 	 * We wanted the peer to authenticate itself, and it refused:
780 	 * if we have some address(es) it can use without auth, fine,
781 	 * otherwise treat it as though it authenticated with PAP using
782 	 * a username of "" and a password of "".  If that's not OK,
783 	 * boot it out.
784 	 */
785 	if (noauth_addrs != NULL) {
786 	    set_allowed_addrs(unit, NULL, NULL);
787 	} else
788 #endif /* PPP_ALLOWED_ADDRS */
789 	if (!pcb->settings.null_login
790 #if PAP_SUPPORT
791 	    || !wo->neg_upap
792 #endif /* PAP_SUPPORT */
793 	    ) {
794 	    ppp_warn("peer refused to authenticate: terminating link");
795 #if 0 /* UNUSED */
796 	    status = EXIT_PEER_AUTH_FAILED;
797 #endif /* UNUSED */
798 	    pcb->err_code = PPPERR_AUTHFAIL;
799 	    lcp_close(pcb, "peer refused to authenticate");
800 	    return;
801 	}
802     }
803 #endif /* PPP_SERVER */
804 
805     new_phase(pcb, PPP_PHASE_AUTHENTICATE);
806     auth = 0;
807 #if PPP_SERVER
808 #if EAP_SUPPORT
809     if (go->neg_eap) {
810 	eap_authpeer(pcb, PPP_OUR_NAME);
811 	auth |= EAP_PEER;
812     } else
813 #endif /* EAP_SUPPORT */
814 #if CHAP_SUPPORT
815     if (go->neg_chap) {
816 	chap_auth_peer(pcb, PPP_OUR_NAME, CHAP_DIGEST(go->chap_mdtype));
817 	auth |= CHAP_PEER;
818     } else
819 #endif /* CHAP_SUPPORT */
820 #if PAP_SUPPORT
821     if (go->neg_upap) {
822 	upap_authpeer(pcb);
823 	auth |= PAP_PEER;
824     } else
825 #endif /* PAP_SUPPORT */
826     {}
827 #endif /* PPP_SERVER */
828 
829 #if EAP_SUPPORT
830     if (ho->neg_eap) {
831 	eap_authwithpeer(pcb, pcb->settings.user);
832 	auth |= EAP_WITHPEER;
833     } else
834 #endif /* EAP_SUPPORT */
835 #if CHAP_SUPPORT
836     if (ho->neg_chap) {
837 	chap_auth_with_peer(pcb, pcb->settings.user, CHAP_DIGEST(ho->chap_mdtype));
838 	auth |= CHAP_WITHPEER;
839     } else
840 #endif /* CHAP_SUPPORT */
841 #if PAP_SUPPORT
842     if (ho->neg_upap) {
843 	upap_authwithpeer(pcb, pcb->settings.user, pcb->settings.passwd);
844 	auth |= PAP_WITHPEER;
845     } else
846 #endif /* PAP_SUPPORT */
847     {}
848 
849     pcb->auth_pending = auth;
850     pcb->auth_done = 0;
851 
852     if (!auth)
853 #endif /* PPP_AUTH_SUPPORT */
854 	network_phase(pcb);
855 }
856 
857 /*
858  * Proceed to the network phase.
859  */
network_phase(ppp_pcb * pcb)860 static void network_phase(ppp_pcb *pcb) {
861 #if CBCP_SUPPORT
862     ppp_pcb *pcb = &ppp_pcb_list[unit];
863 #endif
864 #if 0 /* UNUSED */
865     lcp_options *go = &lcp_gotoptions[unit];
866 #endif /* UNUSED */
867 
868 #if 0 /* UNUSED */
869     /* Log calling number. */
870     if (*remote_number)
871 	ppp_notice("peer from calling number %q authorized", remote_number);
872 #endif /* UNUSED */
873 
874 #if PPP_NOTIFY
875     /*
876      * If the peer had to authenticate, notify it now.
877      */
878     if (0
879 #if CHAP_SUPPORT
880 	|| go->neg_chap
881 #endif /* CHAP_SUPPORT */
882 #if PAP_SUPPORT
883 	|| go->neg_upap
884 #endif /* PAP_SUPPORT */
885 #if EAP_SUPPORT
886 	|| go->neg_eap
887 #endif /* EAP_SUPPORT */
888 	) {
889 	notify(auth_up_notifier, 0);
890     }
891 #endif /* PPP_NOTIFY */
892 
893 #if CBCP_SUPPORT
894     /*
895      * If we negotiated callback, do it now.
896      */
897     if (go->neg_cbcp) {
898 	new_phase(pcb, PPP_PHASE_CALLBACK);
899 	(*cbcp_protent.open)(pcb);
900 	return;
901     }
902 #endif
903 
904 #if PPP_OPTIONS
905     /*
906      * Process extra options from the secrets file
907      */
908     if (extra_options) {
909 	options_from_list(extra_options, 1);
910 	free_wordlist(extra_options);
911 	extra_options = 0;
912     }
913 #endif /* PPP_OPTIONS */
914     start_networks(pcb);
915 }
916 
start_networks(ppp_pcb * pcb)917 void start_networks(ppp_pcb *pcb) {
918 #if CCP_SUPPORT || ECP_SUPPORT
919     int i;
920     const struct protent *protp;
921 #endif /* CCP_SUPPORT || ECP_SUPPORT */
922 
923     new_phase(pcb, PPP_PHASE_NETWORK);
924 
925 #ifdef HAVE_MULTILINK
926     if (multilink) {
927 	if (mp_join_bundle()) {
928 	    if (multilink_join_hook)
929 		(*multilink_join_hook)();
930 	    if (updetach && !nodetach)
931 		detach();
932 	    return;
933 	}
934     }
935 #endif /* HAVE_MULTILINK */
936 
937 #ifdef PPP_FILTER
938     if (!demand)
939 	set_filters(&pass_filter, &active_filter);
940 #endif
941 #if CCP_SUPPORT || ECP_SUPPORT
942     /* Start CCP and ECP */
943     for (i = 0; (protp = protocols[i]) != NULL; ++i)
944 	if (
945 	    (0
946 #if ECP_SUPPORT
947 	    || protp->protocol == PPP_ECP
948 #endif /* ECP_SUPPORT */
949 #if CCP_SUPPORT
950 	    || protp->protocol == PPP_CCP
951 #endif /* CCP_SUPPORT */
952 	    )
953 	    && protp->open != NULL)
954 	    (*protp->open)(pcb);
955 #endif /* CCP_SUPPORT || ECP_SUPPORT */
956 
957     /*
958      * Bring up other network protocols iff encryption is not required.
959      */
960     if (1
961 #if ECP_SUPPORT
962         && !ecp_gotoptions[unit].required
963 #endif /* ECP_SUPPORT */
964 #if MPPE_SUPPORT
965         && !pcb->ccp_gotoptions.mppe
966 #endif /* MPPE_SUPPORT */
967         )
968 	continue_networks(pcb);
969 }
970 
continue_networks(ppp_pcb * pcb)971 void continue_networks(ppp_pcb *pcb) {
972     int i;
973     const struct protent *protp;
974 
975     /*
976      * Start the "real" network protocols.
977      */
978     for (i = 0; (protp = protocols[i]) != NULL; ++i)
979 	if (protp->protocol < 0xC000
980 #if CCP_SUPPORT
981 	    && protp->protocol != PPP_CCP
982 #endif /* CCP_SUPPORT */
983 #if ECP_SUPPORT
984 	    && protp->protocol != PPP_ECP
985 #endif /* ECP_SUPPORT */
986 	    && protp->open != NULL) {
987 	    (*protp->open)(pcb);
988 	    ++pcb->num_np_open;
989 	}
990 
991     if (pcb->num_np_open == 0)
992 	/* nothing to do */
993 	lcp_close(pcb, "No network protocols running");
994 }
995 
996 #if PPP_AUTH_SUPPORT
997 #if PPP_SERVER
998 /*
999  * auth_check_passwd - Check the user name and passwd against configuration.
1000  *
1001  * returns:
1002  *      0: Authentication failed.
1003  *      1: Authentication succeeded.
1004  * In either case, msg points to an appropriate message and msglen to the message len.
1005  */
auth_check_passwd(ppp_pcb * pcb,char * auser,int userlen,char * apasswd,int passwdlen,const char ** msg,int * msglen)1006 int auth_check_passwd(ppp_pcb *pcb, char *auser, int userlen, char *apasswd, int passwdlen, const char **msg, int *msglen) {
1007   int secretuserlen;
1008   int secretpasswdlen;
1009 
1010   if (pcb->settings.user && pcb->settings.passwd) {
1011     secretuserlen = (int)strlen(pcb->settings.user);
1012     secretpasswdlen = (int)strlen(pcb->settings.passwd);
1013     if (secretuserlen == userlen
1014         && secretpasswdlen == passwdlen
1015         && !memcmp(auser, pcb->settings.user, userlen)
1016         && !memcmp(apasswd, pcb->settings.passwd, passwdlen) ) {
1017       *msg = "Login ok";
1018       *msglen = sizeof("Login ok")-1;
1019       return 1;
1020     }
1021   }
1022 
1023   *msg = "Login incorrect";
1024   *msglen = sizeof("Login incorrect")-1;
1025   return 0;
1026 }
1027 
1028 /*
1029  * The peer has failed to authenticate himself using `protocol'.
1030  */
auth_peer_fail(ppp_pcb * pcb,int protocol)1031 void auth_peer_fail(ppp_pcb *pcb, int protocol) {
1032     LWIP_UNUSED_ARG(protocol);
1033     /*
1034      * Authentication failure: take the link down
1035      */
1036 #if 0 /* UNUSED */
1037     status = EXIT_PEER_AUTH_FAILED;
1038 #endif /* UNUSED */
1039     pcb->err_code = PPPERR_AUTHFAIL;
1040     lcp_close(pcb, "Authentication failed");
1041 }
1042 
1043 /*
1044  * The peer has been successfully authenticated using `protocol'.
1045  */
auth_peer_success(ppp_pcb * pcb,int protocol,int prot_flavor,const char * name,int namelen)1046 void auth_peer_success(ppp_pcb *pcb, int protocol, int prot_flavor, const char *name, int namelen) {
1047     int bit;
1048 #ifndef HAVE_MULTILINK
1049     LWIP_UNUSED_ARG(name);
1050     LWIP_UNUSED_ARG(namelen);
1051 #endif /* HAVE_MULTILINK */
1052 
1053     switch (protocol) {
1054 #if CHAP_SUPPORT
1055     case PPP_CHAP:
1056 	bit = CHAP_PEER;
1057 	switch (prot_flavor) {
1058 	case CHAP_MD5:
1059 	    bit |= CHAP_MD5_PEER;
1060 	    break;
1061 #if MSCHAP_SUPPORT
1062 	case CHAP_MICROSOFT:
1063 	    bit |= CHAP_MS_PEER;
1064 	    break;
1065 	case CHAP_MICROSOFT_V2:
1066 	    bit |= CHAP_MS2_PEER;
1067 	    break;
1068 #endif /* MSCHAP_SUPPORT */
1069 	default:
1070 	    break;
1071 	}
1072 	break;
1073 #endif /* CHAP_SUPPORT */
1074 #if PAP_SUPPORT
1075     case PPP_PAP:
1076 	bit = PAP_PEER;
1077 	break;
1078 #endif /* PAP_SUPPORT */
1079 #if EAP_SUPPORT
1080     case PPP_EAP:
1081 	bit = EAP_PEER;
1082 	break;
1083 #endif /* EAP_SUPPORT */
1084     default:
1085 	ppp_warn("auth_peer_success: unknown protocol %x", protocol);
1086 	return;
1087     }
1088 
1089 #ifdef HAVE_MULTILINK
1090     /*
1091      * Save the authenticated name of the peer for later.
1092      */
1093     if (namelen > (int)sizeof(pcb->peer_authname) - 1)
1094 	namelen = (int)sizeof(pcb->peer_authname) - 1;
1095     MEMCPY(pcb->peer_authname, name, namelen);
1096     pcb->peer_authname[namelen] = 0;
1097 #endif /* HAVE_MULTILINK */
1098 #if 0 /* UNUSED */
1099     script_setenv("PEERNAME", , 0);
1100 #endif /* UNUSED */
1101 
1102     /* Save the authentication method for later. */
1103     pcb->auth_done |= bit;
1104 
1105     /*
1106      * If there is no more authentication still to be done,
1107      * proceed to the network (or callback) phase.
1108      */
1109     if ((pcb->auth_pending &= ~bit) == 0)
1110         network_phase(pcb);
1111 }
1112 #endif /* PPP_SERVER */
1113 
1114 /*
1115  * We have failed to authenticate ourselves to the peer using `protocol'.
1116  */
auth_withpeer_fail(ppp_pcb * pcb,int protocol)1117 void auth_withpeer_fail(ppp_pcb *pcb, int protocol) {
1118     LWIP_UNUSED_ARG(protocol);
1119     /*
1120      * We've failed to authenticate ourselves to our peer.
1121      *
1122      * Some servers keep sending CHAP challenges, but there
1123      * is no point in persisting without any way to get updated
1124      * authentication secrets.
1125      *
1126      * He'll probably take the link down, and there's not much
1127      * we can do except wait for that.
1128      */
1129     pcb->err_code = PPPERR_AUTHFAIL;
1130     lcp_close(pcb, "Failed to authenticate ourselves to peer");
1131 }
1132 
1133 /*
1134  * We have successfully authenticated ourselves with the peer using `protocol'.
1135  */
auth_withpeer_success(ppp_pcb * pcb,int protocol,int prot_flavor)1136 void auth_withpeer_success(ppp_pcb *pcb, int protocol, int prot_flavor) {
1137     int bit;
1138     const char *prot = "";
1139 
1140     switch (protocol) {
1141 #if CHAP_SUPPORT
1142     case PPP_CHAP:
1143 	bit = CHAP_WITHPEER;
1144 	prot = "CHAP";
1145 	switch (prot_flavor) {
1146 	case CHAP_MD5:
1147 	    bit |= CHAP_MD5_WITHPEER;
1148 	    break;
1149 #if MSCHAP_SUPPORT
1150 	case CHAP_MICROSOFT:
1151 	    bit |= CHAP_MS_WITHPEER;
1152 	    break;
1153 	case CHAP_MICROSOFT_V2:
1154 	    bit |= CHAP_MS2_WITHPEER;
1155 	    break;
1156 #endif /* MSCHAP_SUPPORT */
1157 	default:
1158 	    break;
1159 	}
1160 	break;
1161 #endif /* CHAP_SUPPORT */
1162 #if PAP_SUPPORT
1163     case PPP_PAP:
1164 	bit = PAP_WITHPEER;
1165 	prot = "PAP";
1166 	break;
1167 #endif /* PAP_SUPPORT */
1168 #if EAP_SUPPORT
1169     case PPP_EAP:
1170 	bit = EAP_WITHPEER;
1171 	prot = "EAP";
1172 	break;
1173 #endif /* EAP_SUPPORT */
1174     default:
1175 	ppp_warn("auth_withpeer_success: unknown protocol %x", protocol);
1176 	bit = 0;
1177 	/* no break */
1178     }
1179 
1180     ppp_notice("%s authentication succeeded", prot);
1181 
1182     /* Save the authentication method for later. */
1183     pcb->auth_done |= bit;
1184 
1185     /*
1186      * If there is no more authentication still being done,
1187      * proceed to the network (or callback) phase.
1188      */
1189     if ((pcb->auth_pending &= ~bit) == 0)
1190 	network_phase(pcb);
1191 }
1192 #endif /* PPP_AUTH_SUPPORT */
1193 
1194 
1195 /*
1196  * np_up - a network protocol has come up.
1197  */
np_up(ppp_pcb * pcb,int proto)1198 void np_up(ppp_pcb *pcb, int proto) {
1199 #if PPP_IDLETIMELIMIT
1200     int tlim;
1201 #endif /* PPP_IDLETIMELIMIT */
1202     LWIP_UNUSED_ARG(proto);
1203 
1204     if (pcb->num_np_up == 0) {
1205 	/*
1206 	 * At this point we consider that the link has come up successfully.
1207 	 */
1208 	new_phase(pcb, PPP_PHASE_RUNNING);
1209 
1210 #if PPP_IDLETIMELIMIT
1211 #if 0 /* UNUSED */
1212 	if (idle_time_hook != 0)
1213 	    tlim = (*idle_time_hook)(NULL);
1214 	else
1215 #endif /* UNUSED */
1216 	    tlim = pcb->settings.idle_time_limit;
1217 	if (tlim > 0)
1218 	    TIMEOUT(check_idle, (void*)pcb, tlim);
1219 #endif /* PPP_IDLETIMELIMIT */
1220 
1221 #if PPP_MAXCONNECT
1222 	/*
1223 	 * Set a timeout to close the connection once the maximum
1224 	 * connect time has expired.
1225 	 */
1226 	if (pcb->settings.maxconnect > 0)
1227 	    TIMEOUT(connect_time_expired, (void*)pcb, pcb->settings.maxconnect);
1228 #endif /* PPP_MAXCONNECT */
1229 
1230 #ifdef MAXOCTETS
1231 	if (maxoctets > 0)
1232 	    TIMEOUT(check_maxoctets, NULL, maxoctets_timeout);
1233 #endif
1234 
1235 #if 0 /* Unused */
1236 	/*
1237 	 * Detach now, if the updetach option was given.
1238 	 */
1239 	if (updetach && !nodetach)
1240 	    detach();
1241 #endif /* Unused */
1242     }
1243     ++pcb->num_np_up;
1244 }
1245 
1246 /*
1247  * np_down - a network protocol has gone down.
1248  */
np_down(ppp_pcb * pcb,int proto)1249 void np_down(ppp_pcb *pcb, int proto) {
1250     LWIP_UNUSED_ARG(proto);
1251     if (--pcb->num_np_up == 0) {
1252 #if PPP_IDLETIMELIMIT
1253 	UNTIMEOUT(check_idle, (void*)pcb);
1254 #endif /* PPP_IDLETIMELIMIT */
1255 #if PPP_MAXCONNECT
1256 	UNTIMEOUT(connect_time_expired, NULL);
1257 #endif /* PPP_MAXCONNECT */
1258 #ifdef MAXOCTETS
1259 	UNTIMEOUT(check_maxoctets, NULL);
1260 #endif
1261 	new_phase(pcb, PPP_PHASE_NETWORK);
1262     }
1263 }
1264 
1265 /*
1266  * np_finished - a network protocol has finished using the link.
1267  */
np_finished(ppp_pcb * pcb,int proto)1268 void np_finished(ppp_pcb *pcb, int proto) {
1269     LWIP_UNUSED_ARG(proto);
1270     if (--pcb->num_np_open <= 0) {
1271 	/* no further use for the link: shut up shop. */
1272 	lcp_close(pcb, "No network protocols running");
1273     }
1274 }
1275 
1276 #ifdef MAXOCTETS
1277 static void
check_maxoctets(arg)1278 check_maxoctets(arg)
1279     void *arg;
1280 {
1281 #if PPP_STATS_SUPPORT
1282     unsigned int used;
1283 
1284     update_link_stats(ifunit);
1285     link_stats_valid=0;
1286 
1287     switch(maxoctets_dir) {
1288 	case PPP_OCTETS_DIRECTION_IN:
1289 	    used = link_stats.bytes_in;
1290 	    break;
1291 	case PPP_OCTETS_DIRECTION_OUT:
1292 	    used = link_stats.bytes_out;
1293 	    break;
1294 	case PPP_OCTETS_DIRECTION_MAXOVERAL:
1295 	case PPP_OCTETS_DIRECTION_MAXSESSION:
1296 	    used = (link_stats.bytes_in > link_stats.bytes_out) ? link_stats.bytes_in : link_stats.bytes_out;
1297 	    break;
1298 	default:
1299 	    used = link_stats.bytes_in+link_stats.bytes_out;
1300 	    break;
1301     }
1302     if (used > maxoctets) {
1303 	ppp_notice("Traffic limit reached. Limit: %u Used: %u", maxoctets, used);
1304 	status = EXIT_TRAFFIC_LIMIT;
1305 	lcp_close(pcb, "Traffic limit");
1306 #if 0 /* UNUSED */
1307 	need_holdoff = 0;
1308 #endif /* UNUSED */
1309     } else {
1310         TIMEOUT(check_maxoctets, NULL, maxoctets_timeout);
1311     }
1312 #endif /* PPP_STATS_SUPPORT */
1313 }
1314 #endif /* MAXOCTETS */
1315 
1316 #if PPP_IDLETIMELIMIT
1317 /*
1318  * check_idle - check whether the link has been idle for long
1319  * enough that we can shut it down.
1320  */
check_idle(void * arg)1321 static void check_idle(void *arg) {
1322     ppp_pcb *pcb = (ppp_pcb*)arg;
1323     struct ppp_idle idle;
1324     time_t itime;
1325     int tlim;
1326 
1327     if (!get_idle_time(pcb, &idle))
1328 	return;
1329 #if 0 /* UNUSED */
1330     if (idle_time_hook != 0) {
1331 	tlim = idle_time_hook(&idle);
1332     } else {
1333 #endif /* UNUSED */
1334 	itime = LWIP_MIN(idle.xmit_idle, idle.recv_idle);
1335 	tlim = pcb->settings.idle_time_limit - itime;
1336 #if 0 /* UNUSED */
1337     }
1338 #endif /* UNUSED */
1339     if (tlim <= 0) {
1340 	/* link is idle: shut it down. */
1341 	ppp_notice("Terminating connection due to lack of activity.");
1342 	pcb->err_code = PPPERR_IDLETIMEOUT;
1343 	lcp_close(pcb, "Link inactive");
1344 #if 0 /* UNUSED */
1345 	need_holdoff = 0;
1346 #endif /* UNUSED */
1347     } else {
1348 	TIMEOUT(check_idle, (void*)pcb, tlim);
1349     }
1350 }
1351 #endif /* PPP_IDLETIMELIMIT */
1352 
1353 #if PPP_MAXCONNECT
1354 /*
1355  * connect_time_expired - log a message and close the connection.
1356  */
connect_time_expired(void * arg)1357 static void connect_time_expired(void *arg) {
1358     ppp_pcb *pcb = (ppp_pcb*)arg;
1359     ppp_info("Connect time expired");
1360     pcb->err_code = PPPERR_CONNECTTIME;
1361     lcp_close(pcb, "Connect time expired");	/* Close connection */
1362 }
1363 #endif /* PPP_MAXCONNECT */
1364 
1365 #if PPP_OPTIONS
1366 /*
1367  * auth_check_options - called to check authentication options.
1368  */
1369 void
auth_check_options()1370 auth_check_options()
1371 {
1372     lcp_options *wo = &lcp_wantoptions[0];
1373     int can_auth;
1374     int lacks_ip;
1375 
1376     /* Default our_name to hostname, and user to our_name */
1377     if (our_name[0] == 0 || usehostname)
1378 	strlcpy(our_name, hostname, sizeof(our_name));
1379     /* If a blank username was explicitly given as an option, trust
1380        the user and don't use our_name */
1381     if (ppp_settings.user[0] == 0 && !explicit_user)
1382 	strlcpy(ppp_settings.user, our_name, sizeof(ppp_settings.user));
1383 
1384     /*
1385      * If we have a default route, require the peer to authenticate
1386      * unless the noauth option was given or the real user is root.
1387      */
1388     if (!auth_required && !allow_any_ip && have_route_to(0) && !privileged) {
1389 	auth_required = 1;
1390 	default_auth = 1;
1391     }
1392 
1393 #if CHAP_SUPPORT
1394     /* If we selected any CHAP flavors, we should probably negotiate it. :-) */
1395     if (wo->chap_mdtype)
1396 	wo->neg_chap = 1;
1397 #endif /* CHAP_SUPPORT */
1398 
1399     /* If authentication is required, ask peer for CHAP, PAP, or EAP. */
1400     if (auth_required) {
1401 	allow_any_ip = 0;
1402 	if (1
1403 #if CHAP_SUPPORT
1404 	    && !wo->neg_chap
1405 #endif /* CHAP_SUPPORT */
1406 #if PAP_SUPPORT
1407 	    && !wo->neg_upap
1408 #endif /* PAP_SUPPORT */
1409 #if EAP_SUPPORT
1410 	    && !wo->neg_eap
1411 #endif /* EAP_SUPPORT */
1412 	    ) {
1413 #if CHAP_SUPPORT
1414 	    wo->neg_chap = CHAP_MDTYPE_SUPPORTED != MDTYPE_NONE;
1415 	    wo->chap_mdtype = CHAP_MDTYPE_SUPPORTED;
1416 #endif /* CHAP_SUPPORT */
1417 #if PAP_SUPPORT
1418 	    wo->neg_upap = 1;
1419 #endif /* PAP_SUPPORT */
1420 #if EAP_SUPPORT
1421 	    wo->neg_eap = 1;
1422 #endif /* EAP_SUPPORT */
1423 	}
1424     } else {
1425 #if CHAP_SUPPORT
1426 	wo->neg_chap = 0;
1427 	wo->chap_mdtype = MDTYPE_NONE;
1428 #endif /* CHAP_SUPPORT */
1429 #if PAP_SUPPORT
1430 	wo->neg_upap = 0;
1431 #endif /* PAP_SUPPORT */
1432 #if EAP_SUPPORT
1433 	wo->neg_eap = 0;
1434 #endif /* EAP_SUPPORT */
1435     }
1436 
1437     /*
1438      * Check whether we have appropriate secrets to use
1439      * to authenticate the peer.  Note that EAP can authenticate by way
1440      * of a CHAP-like exchanges as well as SRP.
1441      */
1442     lacks_ip = 0;
1443 #if PAP_SUPPORT
1444     can_auth = wo->neg_upap && (uselogin || have_pap_secret(&lacks_ip));
1445 #else
1446     can_auth = 0;
1447 #endif /* PAP_SUPPORT */
1448     if (!can_auth && (0
1449 #if CHAP_SUPPORT
1450 	|| wo->neg_chap
1451 #endif /* CHAP_SUPPORT */
1452 #if EAP_SUPPORT
1453 	|| wo->neg_eap
1454 #endif /* EAP_SUPPORT */
1455 	)) {
1456 #if CHAP_SUPPORT
1457 	can_auth = have_chap_secret((explicit_remote? remote_name: NULL),
1458 				    our_name, 1, &lacks_ip);
1459 #else
1460 	can_auth = 0;
1461 #endif
1462     }
1463     if (!can_auth
1464 #if EAP_SUPPORT
1465 	&& wo->neg_eap
1466 #endif /* EAP_SUPPORT */
1467 	) {
1468 	can_auth = have_srp_secret((explicit_remote? remote_name: NULL),
1469 				    our_name, 1, &lacks_ip);
1470     }
1471 
1472     if (auth_required && !can_auth && noauth_addrs == NULL) {
1473 	if (default_auth) {
1474 	    option_error(
1475 "By default the remote system is required to authenticate itself");
1476 	    option_error(
1477 "(because this system has a default route to the internet)");
1478 	} else if (explicit_remote)
1479 	    option_error(
1480 "The remote system (%s) is required to authenticate itself",
1481 			 remote_name);
1482 	else
1483 	    option_error(
1484 "The remote system is required to authenticate itself");
1485 	option_error(
1486 "but I couldn't find any suitable secret (password) for it to use to do so.");
1487 	if (lacks_ip)
1488 	    option_error(
1489 "(None of the available passwords would let it use an IP address.)");
1490 
1491 	exit(1);
1492     }
1493 
1494     /*
1495      * Early check for remote number authorization.
1496      */
1497     if (!auth_number()) {
1498 	ppp_warn("calling number %q is not authorized", remote_number);
1499 	exit(EXIT_CNID_AUTH_FAILED);
1500     }
1501 }
1502 #endif /* PPP_OPTIONS */
1503 
1504 #if 0 /* UNUSED */
1505 /*
1506  * auth_reset - called when LCP is starting negotiations to recheck
1507  * authentication options, i.e. whether we have appropriate secrets
1508  * to use for authenticating ourselves and/or the peer.
1509  */
1510 void
1511 auth_reset(unit)
1512     int unit;
1513 {
1514     lcp_options *go = &lcp_gotoptions[unit];
1515     lcp_options *ao = &lcp_allowoptions[unit];
1516     int hadchap;
1517 
1518     hadchap = -1;
1519     ao->neg_upap = !refuse_pap && (passwd[0] != 0 || get_pap_passwd(NULL));
1520     ao->neg_chap = (!refuse_chap || !refuse_mschap || !refuse_mschap_v2)
1521 	&& (passwd[0] != 0 ||
1522 	    (hadchap = have_chap_secret(user, (explicit_remote? remote_name:
1523 					       NULL), 0, NULL)));
1524     ao->neg_eap = !refuse_eap && (
1525 	passwd[0] != 0 ||
1526 	(hadchap == 1 || (hadchap == -1 && have_chap_secret(user,
1527 	    (explicit_remote? remote_name: NULL), 0, NULL))) ||
1528 	have_srp_secret(user, (explicit_remote? remote_name: NULL), 0, NULL));
1529 
1530     hadchap = -1;
1531     if (go->neg_upap && !uselogin && !have_pap_secret(NULL))
1532 	go->neg_upap = 0;
1533     if (go->neg_chap) {
1534 	if (!(hadchap = have_chap_secret((explicit_remote? remote_name: NULL),
1535 			      our_name, 1, NULL)))
1536 	    go->neg_chap = 0;
1537     }
1538     if (go->neg_eap &&
1539 	(hadchap == 0 || (hadchap == -1 &&
1540 	    !have_chap_secret((explicit_remote? remote_name: NULL), our_name,
1541 		1, NULL))) &&
1542 	!have_srp_secret((explicit_remote? remote_name: NULL), our_name, 1,
1543 	    NULL))
1544 	go->neg_eap = 0;
1545 }
1546 
1547 /*
1548  * check_passwd - Check the user name and passwd against the PAP secrets
1549  * file.  If requested, also check against the system password database,
1550  * and login the user if OK.
1551  *
1552  * returns:
1553  *	UPAP_AUTHNAK: Authentication failed.
1554  *	UPAP_AUTHACK: Authentication succeeded.
1555  * In either case, msg points to an appropriate message.
1556  */
1557 int
1558 check_passwd(unit, auser, userlen, apasswd, passwdlen, msg)
1559     int unit;
1560     char *auser;
1561     int userlen;
1562     char *apasswd;
1563     int passwdlen;
1564     char **msg;
1565 {
1566   return UPAP_AUTHNAK;
1567     int ret;
1568     char *filename;
1569     FILE *f;
1570     struct wordlist *addrs = NULL, *opts = NULL;
1571     char passwd[256], user[256];
1572     char secret[MAXWORDLEN];
1573     static int attempts = 0;
1574 
1575     /*
1576      * Make copies of apasswd and auser, then null-terminate them.
1577      * If there are unprintable characters in the password, make
1578      * them visible.
1579      */
1580     slprintf(ppp_settings.passwd, sizeof(ppp_settings.passwd), "%.*v", passwdlen, apasswd);
1581     slprintf(ppp_settings.user, sizeof(ppp_settings.user), "%.*v", userlen, auser);
1582     *msg = "";
1583 
1584     /*
1585      * Check if a plugin wants to handle this.
1586      */
1587     if (pap_auth_hook) {
1588 	ret = (*pap_auth_hook)(ppp_settings.user, ppp_settings.passwd, msg, &addrs, &opts);
1589 	if (ret >= 0) {
1590 	    /* note: set_allowed_addrs() saves opts (but not addrs):
1591 	       don't free it! */
1592 	    if (ret)
1593 		set_allowed_addrs(unit, addrs, opts);
1594 	    else if (opts != 0)
1595 		free_wordlist(opts);
1596 	    if (addrs != 0)
1597 		free_wordlist(addrs);
1598 	    BZERO(ppp_settings.passwd, sizeof(ppp_settings.passwd));
1599 	    return ret? UPAP_AUTHACK: UPAP_AUTHNAK;
1600 	}
1601     }
1602 
1603     /*
1604      * Open the file of pap secrets and scan for a suitable secret
1605      * for authenticating this user.
1606      */
1607     filename = _PATH_UPAPFILE;
1608     addrs = opts = NULL;
1609     ret = UPAP_AUTHNAK;
1610     f = fopen(filename, "r");
1611     if (f == NULL) {
1612 	ppp_error("Can't open PAP password file %s: %m", filename);
1613 
1614     } else {
1615 	check_access(f, filename);
1616 	if (scan_authfile(f, ppp_settings.user, our_name, secret, &addrs, &opts, filename, 0) < 0) {
1617 	    ppp_warn("no PAP secret found for %s", user);
1618 	} else {
1619 	    /*
1620 	     * If the secret is "@login", it means to check
1621 	     * the password against the login database.
1622 	     */
1623 	    int login_secret = strcmp(secret, "@login") == 0;
1624 	    ret = UPAP_AUTHACK;
1625 	    if (uselogin || login_secret) {
1626 		/* login option or secret is @login */
1627 		if (session_full(ppp_settings.user, ppp_settings.passwd, devnam, msg) == 0) {
1628 		    ret = UPAP_AUTHNAK;
1629 		}
1630 	    } else if (session_mgmt) {
1631 		if (session_check(ppp_settings.user, NULL, devnam, NULL) == 0) {
1632 		    ppp_warn("Peer %q failed PAP Session verification", user);
1633 		    ret = UPAP_AUTHNAK;
1634 		}
1635 	    }
1636 	    if (secret[0] != 0 && !login_secret) {
1637 		/* password given in pap-secrets - must match */
1638 		if ((cryptpap || strcmp(ppp_settings.passwd, secret) != 0)
1639 		    && strcmp(crypt(ppp_settings.passwd, secret), secret) != 0)
1640 		    ret = UPAP_AUTHNAK;
1641 	    }
1642 	}
1643 	fclose(f);
1644     }
1645 
1646     if (ret == UPAP_AUTHNAK) {
1647         if (**msg == 0)
1648 	    *msg = "Login incorrect";
1649 	/*
1650 	 * XXX can we ever get here more than once??
1651 	 * Frustrate passwd stealer programs.
1652 	 * Allow 10 tries, but start backing off after 3 (stolen from login).
1653 	 * On 10'th, drop the connection.
1654 	 */
1655 	if (attempts++ >= 10) {
1656 	    ppp_warn("%d LOGIN FAILURES ON %s, %s", attempts, devnam, user);
1657 	    lcp_close(pcb, "login failed");
1658 	}
1659 	if (attempts > 3)
1660 	    sleep((u_int) (attempts - 3) * 5);
1661 	if (opts != NULL)
1662 	    free_wordlist(opts);
1663 
1664     } else {
1665 	attempts = 0;			/* Reset count */
1666 	if (**msg == 0)
1667 	    *msg = "Login ok";
1668 	set_allowed_addrs(unit, addrs, opts);
1669     }
1670 
1671     if (addrs != NULL)
1672 	free_wordlist(addrs);
1673     BZERO(ppp_settings.passwd, sizeof(ppp_settings.passwd));
1674     BZERO(secret, sizeof(secret));
1675 
1676     return ret;
1677 }
1678 
1679 /*
1680  * null_login - Check if a username of "" and a password of "" are
1681  * acceptable, and iff so, set the list of acceptable IP addresses
1682  * and return 1.
1683  */
1684 static int
1685 null_login(unit)
1686     int unit;
1687 {
1688     char *filename;
1689     FILE *f;
1690     int i, ret;
1691     struct wordlist *addrs, *opts;
1692     char secret[MAXWORDLEN];
1693 
1694     /*
1695      * Check if a plugin wants to handle this.
1696      */
1697     ret = -1;
1698     if (null_auth_hook)
1699 	ret = (*null_auth_hook)(&addrs, &opts);
1700 
1701     /*
1702      * Open the file of pap secrets and scan for a suitable secret.
1703      */
1704     if (ret <= 0) {
1705 	filename = _PATH_UPAPFILE;
1706 	addrs = NULL;
1707 	f = fopen(filename, "r");
1708 	if (f == NULL)
1709 	    return 0;
1710 	check_access(f, filename);
1711 
1712 	i = scan_authfile(f, "", our_name, secret, &addrs, &opts, filename, 0);
1713 	ret = i >= 0 && secret[0] == 0;
1714 	BZERO(secret, sizeof(secret));
1715 	fclose(f);
1716     }
1717 
1718     if (ret)
1719 	set_allowed_addrs(unit, addrs, opts);
1720     else if (opts != 0)
1721 	free_wordlist(opts);
1722     if (addrs != 0)
1723 	free_wordlist(addrs);
1724 
1725     return ret;
1726 }
1727 
1728 /*
1729  * get_pap_passwd - get a password for authenticating ourselves with
1730  * our peer using PAP.  Returns 1 on success, 0 if no suitable password
1731  * could be found.
1732  * Assumes passwd points to MAXSECRETLEN bytes of space (if non-null).
1733  */
1734 static int
1735 get_pap_passwd(passwd)
1736     char *passwd;
1737 {
1738     char *filename;
1739     FILE *f;
1740     int ret;
1741     char secret[MAXWORDLEN];
1742 
1743     /*
1744      * Check whether a plugin wants to supply this.
1745      */
1746     if (pap_passwd_hook) {
1747 	ret = (*pap_passwd_hook)(ppp_settings,user, ppp_settings.passwd);
1748 	if (ret >= 0)
1749 	    return ret;
1750     }
1751 
1752     filename = _PATH_UPAPFILE;
1753     f = fopen(filename, "r");
1754     if (f == NULL)
1755 	return 0;
1756     check_access(f, filename);
1757     ret = scan_authfile(f, user,
1758 			(remote_name[0]? remote_name: NULL),
1759 			secret, NULL, NULL, filename, 0);
1760     fclose(f);
1761     if (ret < 0)
1762 	return 0;
1763     if (passwd != NULL)
1764 	strlcpy(passwd, secret, MAXSECRETLEN);
1765     BZERO(secret, sizeof(secret));
1766     return 1;
1767 }
1768 
1769 /*
1770  * have_pap_secret - check whether we have a PAP file with any
1771  * secrets that we could possibly use for authenticating the peer.
1772  */
1773 static int
1774 have_pap_secret(lacks_ipp)
1775     int *lacks_ipp;
1776 {
1777     FILE *f;
1778     int ret;
1779     char *filename;
1780     struct wordlist *addrs;
1781 
1782     /* let the plugin decide, if there is one */
1783     if (pap_check_hook) {
1784 	ret = (*pap_check_hook)();
1785 	if (ret >= 0)
1786 	    return ret;
1787     }
1788 
1789     filename = _PATH_UPAPFILE;
1790     f = fopen(filename, "r");
1791     if (f == NULL)
1792 	return 0;
1793 
1794     ret = scan_authfile(f, (explicit_remote? remote_name: NULL), our_name,
1795 			NULL, &addrs, NULL, filename, 0);
1796     fclose(f);
1797     if (ret >= 0 && !some_ip_ok(addrs)) {
1798 	if (lacks_ipp != 0)
1799 	    *lacks_ipp = 1;
1800 	ret = -1;
1801     }
1802     if (addrs != 0)
1803 	free_wordlist(addrs);
1804 
1805     return ret >= 0;
1806 }
1807 
1808 /*
1809  * have_chap_secret - check whether we have a CHAP file with a
1810  * secret that we could possibly use for authenticating `client'
1811  * on `server'.  Either can be the null string, meaning we don't
1812  * know the identity yet.
1813  */
1814 static int
1815 have_chap_secret(client, server, need_ip, lacks_ipp)
1816     char *client;
1817     char *server;
1818     int need_ip;
1819     int *lacks_ipp;
1820 {
1821     FILE *f;
1822     int ret;
1823     char *filename;
1824     struct wordlist *addrs;
1825 
1826     if (chap_check_hook) {
1827 	ret = (*chap_check_hook)();
1828 	if (ret >= 0) {
1829 	    return ret;
1830 	}
1831     }
1832 
1833     filename = _PATH_CHAPFILE;
1834     f = fopen(filename, "r");
1835     if (f == NULL)
1836 	return 0;
1837 
1838     if (client != NULL && client[0] == 0)
1839 	client = NULL;
1840     else if (server != NULL && server[0] == 0)
1841 	server = NULL;
1842 
1843     ret = scan_authfile(f, client, server, NULL, &addrs, NULL, filename, 0);
1844     fclose(f);
1845     if (ret >= 0 && need_ip && !some_ip_ok(addrs)) {
1846 	if (lacks_ipp != 0)
1847 	    *lacks_ipp = 1;
1848 	ret = -1;
1849     }
1850     if (addrs != 0)
1851 	free_wordlist(addrs);
1852 
1853     return ret >= 0;
1854 }
1855 
1856 /*
1857  * have_srp_secret - check whether we have a SRP file with a
1858  * secret that we could possibly use for authenticating `client'
1859  * on `server'.  Either can be the null string, meaning we don't
1860  * know the identity yet.
1861  */
1862 static int
1863 have_srp_secret(client, server, need_ip, lacks_ipp)
1864     char *client;
1865     char *server;
1866     int need_ip;
1867     int *lacks_ipp;
1868 {
1869     FILE *f;
1870     int ret;
1871     char *filename;
1872     struct wordlist *addrs;
1873 
1874     filename = _PATH_SRPFILE;
1875     f = fopen(filename, "r");
1876     if (f == NULL)
1877 	return 0;
1878 
1879     if (client != NULL && client[0] == 0)
1880 	client = NULL;
1881     else if (server != NULL && server[0] == 0)
1882 	server = NULL;
1883 
1884     ret = scan_authfile(f, client, server, NULL, &addrs, NULL, filename, 0);
1885     fclose(f);
1886     if (ret >= 0 && need_ip && !some_ip_ok(addrs)) {
1887 	if (lacks_ipp != 0)
1888 	    *lacks_ipp = 1;
1889 	ret = -1;
1890     }
1891     if (addrs != 0)
1892 	free_wordlist(addrs);
1893 
1894     return ret >= 0;
1895 }
1896 #endif /* UNUSED */
1897 
1898 #if PPP_AUTH_SUPPORT
1899 /*
1900  * get_secret - open the CHAP secret file and return the secret
1901  * for authenticating the given client on the given server.
1902  * (We could be either client or server).
1903  */
get_secret(ppp_pcb * pcb,const char * client,const char * server,char * secret,int * secret_len,int am_server)1904 int get_secret(ppp_pcb *pcb, const char *client, const char *server, char *secret, int *secret_len, int am_server) {
1905   int len;
1906   LWIP_UNUSED_ARG(server);
1907   LWIP_UNUSED_ARG(am_server);
1908 
1909   if (!client || !client[0] || !pcb->settings.user || !pcb->settings.passwd || strcmp(client, pcb->settings.user)) {
1910     return 0;
1911   }
1912 
1913   len = (int)strlen(pcb->settings.passwd);
1914   if (len > MAXSECRETLEN) {
1915     ppp_error("Secret for %s on %s is too long", client, server);
1916     len = MAXSECRETLEN;
1917   }
1918 
1919   MEMCPY(secret, pcb->settings.passwd, len);
1920   *secret_len = len;
1921   return 1;
1922 
1923 #if 0 /* UNUSED */
1924     FILE *f;
1925     int ret, len;
1926     char *filename;
1927     struct wordlist *addrs, *opts;
1928     char secbuf[MAXWORDLEN];
1929     struct wordlist *addrs;
1930     addrs = NULL;
1931 
1932     if (!am_server && ppp_settings.passwd[0] != 0) {
1933 	strlcpy(secbuf, ppp_settings.passwd, sizeof(secbuf));
1934     } else if (!am_server && chap_passwd_hook) {
1935 	if ( (*chap_passwd_hook)(client, secbuf) < 0) {
1936 	    ppp_error("Unable to obtain CHAP password for %s on %s from plugin",
1937 		  client, server);
1938 	    return 0;
1939 	}
1940     } else {
1941 	filename = _PATH_CHAPFILE;
1942 	addrs = NULL;
1943 	secbuf[0] = 0;
1944 
1945 	f = fopen(filename, "r");
1946 	if (f == NULL) {
1947 	    ppp_error("Can't open chap secret file %s: %m", filename);
1948 	    return 0;
1949 	}
1950 	check_access(f, filename);
1951 
1952 	ret = scan_authfile(f, client, server, secbuf, &addrs, &opts, filename, 0);
1953 	fclose(f);
1954 	if (ret < 0)
1955 	    return 0;
1956 
1957 	if (am_server)
1958 	    set_allowed_addrs(unit, addrs, opts);
1959 	else if (opts != 0)
1960 	    free_wordlist(opts);
1961 	if (addrs != 0)
1962 	    free_wordlist(addrs);
1963     }
1964 
1965     len = strlen(secbuf);
1966     if (len > MAXSECRETLEN) {
1967 	ppp_error("Secret for %s on %s is too long", client, server);
1968 	len = MAXSECRETLEN;
1969     }
1970     MEMCPY(secret, secbuf, len);
1971     BZERO(secbuf, sizeof(secbuf));
1972     *secret_len = len;
1973 
1974     return 1;
1975 #endif /* UNUSED */
1976 }
1977 #endif /* PPP_AUTH_SUPPORT */
1978 
1979 
1980 #if 0 /* UNUSED */
1981 /*
1982  * get_srp_secret - open the SRP secret file and return the secret
1983  * for authenticating the given client on the given server.
1984  * (We could be either client or server).
1985  */
1986 int
1987 get_srp_secret(unit, client, server, secret, am_server)
1988     int unit;
1989     char *client;
1990     char *server;
1991     char *secret;
1992     int am_server;
1993 {
1994     FILE *fp;
1995     int ret;
1996     char *filename;
1997     struct wordlist *addrs, *opts;
1998 
1999     if (!am_server && ppp_settings.passwd[0] != '\0') {
2000 	strlcpy(secret, ppp_settings.passwd, MAXWORDLEN);
2001     } else {
2002 	filename = _PATH_SRPFILE;
2003 	addrs = NULL;
2004 
2005 	fp = fopen(filename, "r");
2006 	if (fp == NULL) {
2007 	    ppp_error("Can't open srp secret file %s: %m", filename);
2008 	    return 0;
2009 	}
2010 	check_access(fp, filename);
2011 
2012 	secret[0] = '\0';
2013 	ret = scan_authfile(fp, client, server, secret, &addrs, &opts,
2014 	    filename, am_server);
2015 	fclose(fp);
2016 	if (ret < 0)
2017 	    return 0;
2018 
2019 	if (am_server)
2020 	    set_allowed_addrs(unit, addrs, opts);
2021 	else if (opts != NULL)
2022 	    free_wordlist(opts);
2023 	if (addrs != NULL)
2024 	    free_wordlist(addrs);
2025     }
2026 
2027     return 1;
2028 }
2029 
2030 /*
2031  * set_allowed_addrs() - set the list of allowed addresses.
2032  * Also looks for `--' indicating options to apply for this peer
2033  * and leaves the following words in extra_options.
2034  */
2035 static void
2036 set_allowed_addrs(unit, addrs, opts)
2037     int unit;
2038     struct wordlist *addrs;
2039     struct wordlist *opts;
2040 {
2041     int n;
2042     struct wordlist *ap, **plink;
2043     struct permitted_ip *ip;
2044     char *ptr_word, *ptr_mask;
2045     struct hostent *hp;
2046     struct netent *np;
2047     u32_t a, mask, ah, offset;
2048     struct ipcp_options *wo = &ipcp_wantoptions[unit];
2049     u32_t suggested_ip = 0;
2050 
2051     if (addresses[unit] != NULL)
2052 	free(addresses[unit]);
2053     addresses[unit] = NULL;
2054     if (extra_options != NULL)
2055 	free_wordlist(extra_options);
2056     extra_options = opts;
2057 
2058     /*
2059      * Count the number of IP addresses given.
2060      */
2061     n = wordlist_count(addrs) + wordlist_count(noauth_addrs);
2062     if (n == 0)
2063 	return;
2064     ip = (struct permitted_ip *) malloc((n + 1) * sizeof(struct permitted_ip));
2065     if (ip == 0)
2066 	return;
2067 
2068     /* temporarily append the noauth_addrs list to addrs */
2069     for (plink = &addrs; *plink != NULL; plink = &(*plink)->next)
2070 	;
2071     *plink = noauth_addrs;
2072 
2073     n = 0;
2074     for (ap = addrs; ap != NULL; ap = ap->next) {
2075 	/* "-" means no addresses authorized, "*" means any address allowed */
2076 	ptr_word = ap->word;
2077 	if (strcmp(ptr_word, "-") == 0)
2078 	    break;
2079 	if (strcmp(ptr_word, "*") == 0) {
2080 	    ip[n].permit = 1;
2081 	    ip[n].base = ip[n].mask = 0;
2082 	    ++n;
2083 	    break;
2084 	}
2085 
2086 	ip[n].permit = 1;
2087 	if (*ptr_word == '!') {
2088 	    ip[n].permit = 0;
2089 	    ++ptr_word;
2090 	}
2091 
2092 	mask = ~ (u32_t) 0;
2093 	offset = 0;
2094 	ptr_mask = strchr (ptr_word, '/');
2095 	if (ptr_mask != NULL) {
2096 	    int bit_count;
2097 	    char *endp;
2098 
2099 	    bit_count = (int) strtol (ptr_mask+1, &endp, 10);
2100 	    if (bit_count <= 0 || bit_count > 32) {
2101 		ppp_warn("invalid address length %v in auth. address list",
2102 		     ptr_mask+1);
2103 		continue;
2104 	    }
2105 	    bit_count = 32 - bit_count;	/* # bits in host part */
2106 	    if (*endp == '+') {
2107 		offset = ifunit + 1;
2108 		++endp;
2109 	    }
2110 	    if (*endp != 0) {
2111 		ppp_warn("invalid address length syntax: %v", ptr_mask+1);
2112 		continue;
2113 	    }
2114 	    *ptr_mask = '\0';
2115 	    mask <<= bit_count;
2116 	}
2117 
2118 	hp = gethostbyname(ptr_word);
2119 	if (hp != NULL && hp->h_addrtype == AF_INET) {
2120 	    a = *(u32_t *)hp->h_addr;
2121 	} else {
2122 	    np = getnetbyname (ptr_word);
2123 	    if (np != NULL && np->n_addrtype == AF_INET) {
2124 		a = lwip_htonl ((u32_t)np->n_net);
2125 		if (ptr_mask == NULL) {
2126 		    /* calculate appropriate mask for net */
2127 		    ah = lwip_ntohl(a);
2128 		    if (IN_CLASSA(ah))
2129 			mask = IN_CLASSA_NET;
2130 		    else if (IN_CLASSB(ah))
2131 			mask = IN_CLASSB_NET;
2132 		    else if (IN_CLASSC(ah))
2133 			mask = IN_CLASSC_NET;
2134 		}
2135 	    } else {
2136 		a = inet_addr (ptr_word);
2137 	    }
2138 	}
2139 
2140 	if (ptr_mask != NULL)
2141 	    *ptr_mask = '/';
2142 
2143 	if (a == (u32_t)-1L) {
2144 	    ppp_warn("unknown host %s in auth. address list", ap->word);
2145 	    continue;
2146 	}
2147 	if (offset != 0) {
2148 	    if (offset >= ~mask) {
2149 		ppp_warn("interface unit %d too large for subnet %v",
2150 		     ifunit, ptr_word);
2151 		continue;
2152 	    }
2153 	    a = lwip_htonl((lwip_ntohl(a) & mask) + offset);
2154 	    mask = ~(u32_t)0;
2155 	}
2156 	ip[n].mask = lwip_htonl(mask);
2157 	ip[n].base = a & ip[n].mask;
2158 	++n;
2159 	if (~mask == 0 && suggested_ip == 0)
2160 	    suggested_ip = a;
2161     }
2162     *plink = NULL;
2163 
2164     ip[n].permit = 0;		/* make the last entry forbid all addresses */
2165     ip[n].base = 0;		/* to terminate the list */
2166     ip[n].mask = 0;
2167 
2168     addresses[unit] = ip;
2169 
2170     /*
2171      * If the address given for the peer isn't authorized, or if
2172      * the user hasn't given one, AND there is an authorized address
2173      * which is a single host, then use that if we find one.
2174      */
2175     if (suggested_ip != 0
2176 	&& (wo->hisaddr == 0 || !auth_ip_addr(unit, wo->hisaddr))) {
2177 	wo->hisaddr = suggested_ip;
2178 	/*
2179 	 * Do we insist on this address?  No, if there are other
2180 	 * addresses authorized than the suggested one.
2181 	 */
2182 	if (n > 1)
2183 	    wo->accept_remote = 1;
2184     }
2185 }
2186 
2187 /*
2188  * auth_ip_addr - check whether the peer is authorized to use
2189  * a given IP address.  Returns 1 if authorized, 0 otherwise.
2190  */
2191 int
2192 auth_ip_addr(unit, addr)
2193     int unit;
2194     u32_t addr;
2195 {
2196     int ok;
2197 
2198     /* don't allow loopback or multicast address */
2199     if (bad_ip_adrs(addr))
2200 	return 0;
2201 
2202     if (allowed_address_hook) {
2203 	ok = allowed_address_hook(addr);
2204 	if (ok >= 0) return ok;
2205     }
2206 
2207     if (addresses[unit] != NULL) {
2208 	ok = ip_addr_check(addr, addresses[unit]);
2209 	if (ok >= 0)
2210 	    return ok;
2211     }
2212 
2213     if (auth_required)
2214 	return 0;		/* no addresses authorized */
2215     return allow_any_ip || privileged || !have_route_to(addr);
2216 }
2217 
2218 static int
2219 ip_addr_check(addr, addrs)
2220     u32_t addr;
2221     struct permitted_ip *addrs;
2222 {
2223     for (; ; ++addrs)
2224 	if ((addr & addrs->mask) == addrs->base)
2225 	    return addrs->permit;
2226 }
2227 
2228 /*
2229  * bad_ip_adrs - return 1 if the IP address is one we don't want
2230  * to use, such as an address in the loopback net or a multicast address.
2231  * addr is in network byte order.
2232  */
2233 int
2234 bad_ip_adrs(addr)
2235     u32_t addr;
2236 {
2237     addr = lwip_ntohl(addr);
2238     return (addr >> IN_CLASSA_NSHIFT) == IN_LOOPBACKNET
2239 	|| IN_MULTICAST(addr) || IN_BADCLASS(addr);
2240 }
2241 
2242 /*
2243  * some_ip_ok - check a wordlist to see if it authorizes any
2244  * IP address(es).
2245  */
2246 static int
2247 some_ip_ok(addrs)
2248     struct wordlist *addrs;
2249 {
2250     for (; addrs != 0; addrs = addrs->next) {
2251 	if (addrs->word[0] == '-')
2252 	    break;
2253 	if (addrs->word[0] != '!')
2254 	    return 1;		/* some IP address is allowed */
2255     }
2256     return 0;
2257 }
2258 
2259 /*
2260  * auth_number - check whether the remote number is allowed to connect.
2261  * Returns 1 if authorized, 0 otherwise.
2262  */
2263 int
2264 auth_number()
2265 {
2266     struct wordlist *wp = permitted_numbers;
2267     int l;
2268 
2269     /* Allow all if no authorization list. */
2270     if (!wp)
2271 	return 1;
2272 
2273     /* Allow if we have a match in the authorization list. */
2274     while (wp) {
2275 	/* trailing '*' wildcard */
2276 	l = strlen(wp->word);
2277 	if ((wp->word)[l - 1] == '*')
2278 	    l--;
2279 	if (!strncasecmp(wp->word, remote_number, l))
2280 	    return 1;
2281 	wp = wp->next;
2282     }
2283 
2284     return 0;
2285 }
2286 
2287 /*
2288  * check_access - complain if a secret file has too-liberal permissions.
2289  */
2290 static void
2291 check_access(f, filename)
2292     FILE *f;
2293     char *filename;
2294 {
2295     struct stat sbuf;
2296 
2297     if (fstat(fileno(f), &sbuf) < 0) {
2298 	ppp_warn("cannot stat secret file %s: %m", filename);
2299     } else if ((sbuf.st_mode & (S_IRWXG | S_IRWXO)) != 0) {
2300 	ppp_warn("Warning - secret file %s has world and/or group access",
2301 	     filename);
2302     }
2303 }
2304 
2305 /*
2306  * scan_authfile - Scan an authorization file for a secret suitable
2307  * for authenticating `client' on `server'.  The return value is -1
2308  * if no secret is found, otherwise >= 0.  The return value has
2309  * NONWILD_CLIENT set if the secret didn't have "*" for the client, and
2310  * NONWILD_SERVER set if the secret didn't have "*" for the server.
2311  * Any following words on the line up to a "--" (i.e. address authorization
2312  * info) are placed in a wordlist and returned in *addrs.  Any
2313  * following words (extra options) are placed in a wordlist and
2314  * returned in *opts.
2315  * We assume secret is NULL or points to MAXWORDLEN bytes of space.
2316  * Flags are non-zero if we need two colons in the secret in order to
2317  * match.
2318  */
2319 static int
2320 scan_authfile(f, client, server, secret, addrs, opts, filename, flags)
2321     FILE *f;
2322     char *client;
2323     char *server;
2324     char *secret;
2325     struct wordlist **addrs;
2326     struct wordlist **opts;
2327     char *filename;
2328     int flags;
2329 {
2330     int newline, xxx;
2331     int got_flag, best_flag;
2332     FILE *sf;
2333     struct wordlist *ap, *addr_list, *alist, **app;
2334     char word[MAXWORDLEN];
2335     char atfile[MAXWORDLEN];
2336     char lsecret[MAXWORDLEN];
2337     char *cp;
2338 
2339     if (addrs != NULL)
2340 	*addrs = NULL;
2341     if (opts != NULL)
2342 	*opts = NULL;
2343     addr_list = NULL;
2344     if (!getword(f, word, &newline, filename))
2345 	return -1;		/* file is empty??? */
2346     newline = 1;
2347     best_flag = -1;
2348     for (;;) {
2349 	/*
2350 	 * Skip until we find a word at the start of a line.
2351 	 */
2352 	while (!newline && getword(f, word, &newline, filename))
2353 	    ;
2354 	if (!newline)
2355 	    break;		/* got to end of file */
2356 
2357 	/*
2358 	 * Got a client - check if it's a match or a wildcard.
2359 	 */
2360 	got_flag = 0;
2361 	if (client != NULL && strcmp(word, client) != 0 && !ISWILD(word)) {
2362 	    newline = 0;
2363 	    continue;
2364 	}
2365 	if (!ISWILD(word))
2366 	    got_flag = NONWILD_CLIENT;
2367 
2368 	/*
2369 	 * Now get a server and check if it matches.
2370 	 */
2371 	if (!getword(f, word, &newline, filename))
2372 	    break;
2373 	if (newline)
2374 	    continue;
2375 	if (!ISWILD(word)) {
2376 	    if (server != NULL && strcmp(word, server) != 0)
2377 		continue;
2378 	    got_flag |= NONWILD_SERVER;
2379 	}
2380 
2381 	/*
2382 	 * Got some sort of a match - see if it's better than what
2383 	 * we have already.
2384 	 */
2385 	if (got_flag <= best_flag)
2386 	    continue;
2387 
2388 	/*
2389 	 * Get the secret.
2390 	 */
2391 	if (!getword(f, word, &newline, filename))
2392 	    break;
2393 	if (newline)
2394 	    continue;
2395 
2396 	/*
2397 	 * SRP-SHA1 authenticator should never be reading secrets from
2398 	 * a file.  (Authenticatee may, though.)
2399 	 */
2400 	if (flags && ((cp = strchr(word, ':')) == NULL ||
2401 	    strchr(cp + 1, ':') == NULL))
2402 	    continue;
2403 
2404 	if (secret != NULL) {
2405 	    /*
2406 	     * Special syntax: @/pathname means read secret from file.
2407 	     */
2408 	    if (word[0] == '@' && word[1] == '/') {
2409 		strlcpy(atfile, word+1, sizeof(atfile));
2410 		if ((sf = fopen(atfile, "r")) == NULL) {
2411 		    ppp_warn("can't open indirect secret file %s", atfile);
2412 		    continue;
2413 		}
2414 		check_access(sf, atfile);
2415 		if (!getword(sf, word, &xxx, atfile)) {
2416 		    ppp_warn("no secret in indirect secret file %s", atfile);
2417 		    fclose(sf);
2418 		    continue;
2419 		}
2420 		fclose(sf);
2421 	    }
2422 	    strlcpy(lsecret, word, sizeof(lsecret));
2423 	}
2424 
2425 	/*
2426 	 * Now read address authorization info and make a wordlist.
2427 	 */
2428 	app = &alist;
2429 	for (;;) {
2430 	    if (!getword(f, word, &newline, filename) || newline)
2431 		break;
2432 	    ap = (struct wordlist *)
2433 		    malloc(sizeof(struct wordlist) + strlen(word) + 1);
2434 	    if (ap == NULL)
2435 		novm("authorized addresses");
2436 	    ap->word = (char *) (ap + 1);
2437 	    strcpy(ap->word, word);
2438 	    *app = ap;
2439 	    app = &ap->next;
2440 	}
2441 	*app = NULL;
2442 
2443 	/*
2444 	 * This is the best so far; remember it.
2445 	 */
2446 	best_flag = got_flag;
2447 	if (addr_list)
2448 	    free_wordlist(addr_list);
2449 	addr_list = alist;
2450 	if (secret != NULL)
2451 	    strlcpy(secret, lsecret, MAXWORDLEN);
2452 
2453 	if (!newline)
2454 	    break;
2455     }
2456 
2457     /* scan for a -- word indicating the start of options */
2458     for (app = &addr_list; (ap = *app) != NULL; app = &ap->next)
2459 	if (strcmp(ap->word, "--") == 0)
2460 	    break;
2461     /* ap = start of options */
2462     if (ap != NULL) {
2463 	ap = ap->next;		/* first option */
2464 	free(*app);			/* free the "--" word */
2465 	*app = NULL;		/* terminate addr list */
2466     }
2467     if (opts != NULL)
2468 	*opts = ap;
2469     else if (ap != NULL)
2470 	free_wordlist(ap);
2471     if (addrs != NULL)
2472 	*addrs = addr_list;
2473     else if (addr_list != NULL)
2474 	free_wordlist(addr_list);
2475 
2476     return best_flag;
2477 }
2478 
2479 /*
2480  * wordlist_count - return the number of items in a wordlist
2481  */
2482 static int
2483 wordlist_count(wp)
2484     struct wordlist *wp;
2485 {
2486     int n;
2487 
2488     for (n = 0; wp != NULL; wp = wp->next)
2489 	++n;
2490     return n;
2491 }
2492 
2493 /*
2494  * free_wordlist - release memory allocated for a wordlist.
2495  */
2496 static void
2497 free_wordlist(wp)
2498     struct wordlist *wp;
2499 {
2500     struct wordlist *next;
2501 
2502     while (wp != NULL) {
2503 	next = wp->next;
2504 	free(wp);
2505 	wp = next;
2506     }
2507 }
2508 #endif /* UNUSED */
2509 
2510 #endif /* PPP_SUPPORT */
2511