2 * auth.c - PPP authentication and phase control.
4 * Copyright (c) 1993 The Australian National University.
7 * Redistribution and use in source and binary forms are permitted
8 * provided that the above copyright notice and this paragraph are
9 * duplicated in all such forms and that any documentation,
10 * advertising materials, and other materials related to such
11 * distribution and use acknowledge that the software was developed
12 * by the Australian National University. The name of the University
13 * may not be used to endorse or promote products derived from this
14 * software without specific prior written permission.
15 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
16 * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
17 * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
19 * Copyright (c) 1989 Carnegie Mellon University.
20 * All rights reserved.
22 * Redistribution and use in source and binary forms are permitted
23 * provided that the above copyright notice and this paragraph are
24 * duplicated in all such forms and that any documentation,
25 * advertising materials, and other materials related to such
26 * distribution and use acknowledge that the software was developed
27 * by Carnegie Mellon University. The name of the
28 * University may not be used to endorse or promote products derived
29 * from this software without specific prior written permission.
30 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
31 * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
32 * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
36 static char rcsid[] = "$Id: auth.c,v 1.46 1999/03/16 03:15:12 paulus Exp $";
46 #include <sys/types.h>
48 #include <sys/socket.h>
51 #if defined(_PATH_LASTLOG) && defined(_linux_)
56 #include <netinet/in.h>
57 #include <arpa/inet.h>
60 #include <security/pam_appl.h>
66 #define PW_PPP PW_LOGIN
79 #include "pathnames.h"
81 /* Used for storing a sequence of words. Usually malloced. */
83 struct wordlist *next;
87 /* Bits in scan_authfile return value */
88 #define NONWILD_SERVER 1
89 #define NONWILD_CLIENT 2
91 #define ISWILD(word) (word[0] == '*' && word[1] == 0)
96 /* The name by which the peer authenticated itself to us. */
97 char peer_authname[MAXNAMELEN];
99 /* Records which authentication operations haven't completed yet. */
100 static int auth_pending[NUM_PPP];
102 /* Set if we have successfully called plogin() */
103 static int logged_in;
105 /* Set if we have run the /etc/ppp/auth-up script. */
106 static int did_authup;
107 static pid_t authup_pid; /* process ID of auth-up/down script */
109 /* List of addresses which the peer may use. */
110 static struct wordlist *addresses[NUM_PPP];
112 /* Number of network protocols which we have opened. */
113 static int num_np_open;
115 /* Number of network protocols which have come up. */
116 static int num_np_up;
118 /* Set if we got the contents of passwd[] from the pap-secrets file. */
119 static int passwd_from_file;
124 bool uselogin = 0; /* Use /etc/passwd for checking PAP */
125 bool cryptpap = 0; /* Passwords in pap-secrets are encrypted */
126 bool refuse_pap = 0; /* Don't wanna auth. ourselves with PAP */
127 bool refuse_chap = 0; /* Don't wanna auth. ourselves with CHAP */
128 bool usehostname = 0; /* Use hostname for our_name */
129 bool auth_required = 0; /* Always require authentication from peer */
130 bool allow_any_ip = 0; /* Allow peer to use any IP address */
132 /* Bits in auth_pending[] */
133 #define PAP_WITHPEER 1
135 #define CHAP_WITHPEER 4
138 extern char *crypt __P((const char *, const char *));
140 /* Prototypes for procedures local to this file. */
142 static void network_phase __P((int));
143 static void check_idle __P((void *));
144 static void connect_time_expired __P((void *));
145 static int plogin __P((char *, char *, char **, int *));
146 static void plogout __P((void));
147 static int null_login __P((int));
148 static int get_pap_passwd __P((char *));
149 static int have_pap_secret __P((void));
150 static int have_chap_secret __P((char *, char *, u_int32_t));
151 static int ip_addr_check __P((u_int32_t, struct wordlist *));
152 static int scan_authfile __P((FILE *, char *, char *, u_int32_t, char *,
153 struct wordlist **, char *));
154 static void free_wordlist __P((struct wordlist *));
155 static void auth_script __P((char *));
156 static void set_allowed_addrs __P((int, struct wordlist *));
157 static int setupapfile __P((char **));
158 static int privgroup __P((char **));
161 * Authentication-related options.
163 option_t auth_options[] = {
164 { "require-pap", o_bool, &lcp_wantoptions[0].neg_upap,
165 "Require PAP authentication from peer", 1, &auth_required },
166 { "+pap", o_bool, &lcp_wantoptions[0].neg_upap,
167 "Require PAP authentication from peer", 1, &auth_required },
168 { "refuse-pap", o_bool, &refuse_pap,
169 "Don't agree to auth to peer with PAP", 1 },
170 { "-pap", o_bool, &refuse_pap,
171 "Don't allow PAP authentication with peer", 1 },
172 { "require-chap", o_bool, &lcp_wantoptions[0].neg_chap,
173 "Require CHAP authentication from peer", 1, &auth_required },
174 { "+chap", o_bool, &lcp_wantoptions[0].neg_chap,
175 "Require CHAP authentication from peer", 1, &auth_required },
176 { "refuse-chap", o_bool, &refuse_chap,
177 "Don't agree to auth to peer with CHAP", 1 },
178 { "-chap", o_bool, &refuse_chap,
179 "Don't allow CHAP authentication with peer", 1 },
180 { "name", o_string, our_name,
181 "Set local name for authentication",
182 OPT_PRIV|OPT_STATIC, NULL, MAXNAMELEN },
183 { "user", o_string, user,
184 "Set name for auth with peer", OPT_STATIC, NULL, MAXNAMELEN },
185 { "usehostname", o_bool, &usehostname,
186 "Must use hostname for authentication", 1 },
187 { "remotename", o_string, remote_name,
188 "Set remote name for authentication", OPT_STATIC, NULL, MAXNAMELEN },
189 { "auth", o_bool, &auth_required,
190 "Require authentication from peer", 1 },
191 { "noauth", o_bool, &auth_required,
192 "Don't require peer to authenticate", OPT_PRIV, &allow_any_ip },
193 { "login", o_bool, &uselogin,
194 "Use system password database for PAP", 1 },
195 { "papcrypt", o_bool, &cryptpap,
196 "PAP passwords are encrypted", 1 },
197 { "+ua", o_special, setupapfile,
198 "Get PAP user and password from file" },
199 { "privgroup", o_special, privgroup,
200 "Allow group members to use privileged options", OPT_PRIV },
205 * setupapfile - specifies UPAP info for authenticating with peer.
214 lcp_allowoptions[0].neg_upap = 1;
216 /* open user info file */
218 ufile = fopen(*argv, "r");
221 option_error("unable to open user login data file %s", *argv);
224 #if 0 /* check done by setting effective UID above */
225 if (!readable(fileno(ufile))) {
226 option_error("%s: access denied", *argv);
230 check_access(ufile, *argv);
233 if (fgets(user, MAXNAMELEN - 1, ufile) == NULL
234 || fgets(passwd, MAXSECRETLEN - 1, ufile) == NULL){
235 option_error("unable to read user login data file %s", *argv);
240 /* get rid of newlines */
242 if (l > 0 && user[l-1] == '\n')
245 if (l > 0 && passwd[l-1] == '\n')
253 * privgroup - allow members of the group to have privileged access.
264 option_error("group %s is unknown", *argv);
267 for (i = 0; i < ngroups; ++i) {
268 if (groups[i] == g->gr_gid) {
278 * An Open on LCP has requested a change from Dead to Establish phase.
279 * Do what's necessary to bring the physical layer up.
288 * LCP has terminated the link; go to the Dead phase and take the
289 * physical layer down.
292 link_terminated(unit)
295 if (phase == PHASE_DEAD)
300 notice("Connection terminated.");
304 * LCP has gone down; it will either die or try to re-establish.
311 struct protent *protp;
314 auth_script(_PATH_AUTHDOWN);
317 for (i = 0; (protp = protocols[i]) != NULL; ++i) {
318 if (!protp->enabled_flag)
320 if (protp->protocol != PPP_LCP && protp->lowerdown != NULL)
321 (*protp->lowerdown)(unit);
322 if (protp->protocol < 0xC000 && protp->close != NULL)
323 (*protp->close)(unit, "LCP down");
327 if (phase != PHASE_DEAD)
328 phase = PHASE_TERMINATE;
332 * The link is established.
333 * Proceed to the Dead, Authenticate or Network phase as appropriate.
336 link_established(unit)
340 lcp_options *wo = &lcp_wantoptions[unit];
341 lcp_options *go = &lcp_gotoptions[unit];
342 lcp_options *ho = &lcp_hisoptions[unit];
344 struct protent *protp;
347 * Tell higher-level protocols that LCP is up.
349 for (i = 0; (protp = protocols[i]) != NULL; ++i)
350 if (protp->protocol != PPP_LCP && protp->enabled_flag
351 && protp->lowerup != NULL)
352 (*protp->lowerup)(unit);
354 if (auth_required && !(go->neg_chap || go->neg_upap)) {
356 * We wanted the peer to authenticate itself, and it refused:
357 * treat it as though it authenticated with PAP using a username
358 * of "" and a password of "". If that's not OK, boot it out.
360 if (!wo->neg_upap || !null_login(unit)) {
361 warn("peer refused to authenticate: terminating link");
362 lcp_close(unit, "peer refused to authenticate");
367 phase = PHASE_AUTHENTICATE;
370 ChapAuthPeer(unit, our_name, go->chap_mdtype);
372 } else if (go->neg_upap) {
377 ChapAuthWithPeer(unit, user, ho->chap_mdtype);
378 auth |= CHAP_WITHPEER;
379 } else if (ho->neg_upap) {
380 if (passwd[0] == 0) {
381 passwd_from_file = 1;
382 if (!get_pap_passwd(passwd))
383 error("No secret found for PAP login");
385 upap_authwithpeer(unit, user, passwd);
386 auth |= PAP_WITHPEER;
388 auth_pending[unit] = auth;
395 * Proceed to the network phase.
402 struct protent *protp;
403 lcp_options *go = &lcp_gotoptions[unit];
406 * If the peer had to authenticate, run the auth-up script now.
408 if ((go->neg_chap || go->neg_upap) && !did_authup) {
409 auth_script(_PATH_AUTHUP);
415 * If we negotiated callback, do it now.
418 phase = PHASE_CALLBACK;
419 (*cbcp_protent.open)(unit);
424 phase = PHASE_NETWORK;
427 set_filters(&pass_filter, &active_filter);
429 for (i = 0; (protp = protocols[i]) != NULL; ++i)
430 if (protp->protocol < 0xC000 && protp->enabled_flag
431 && protp->open != NULL) {
432 (*protp->open)(unit);
433 if (protp->protocol != PPP_CCP)
437 if (num_np_open == 0)
439 lcp_close(0, "No network protocols running");
443 * The peer has failed to authenticate himself using `protocol'.
446 auth_peer_fail(unit, protocol)
450 * Authentication failure: take the link down
452 lcp_close(unit, "Authentication failed");
456 * The peer has been successfully authenticated using `protocol'.
459 auth_peer_success(unit, protocol, name, namelen)
474 warn("auth_peer_success: unknown protocol %x", protocol);
479 * Save the authenticated name of the peer for later.
481 if (namelen > sizeof(peer_authname) - 1)
482 namelen = sizeof(peer_authname) - 1;
483 BCOPY(name, peer_authname, namelen);
484 peer_authname[namelen] = 0;
485 script_setenv("PEERNAME", peer_authname);
488 * If there is no more authentication still to be done,
489 * proceed to the network (or callback) phase.
491 if ((auth_pending[unit] &= ~bit) == 0)
496 * We have failed to authenticate ourselves to the peer using `protocol'.
499 auth_withpeer_fail(unit, protocol)
502 if (passwd_from_file)
503 BZERO(passwd, MAXSECRETLEN);
505 * We've failed to authenticate ourselves to our peer.
506 * He'll probably take the link down, and there's not much
507 * we can do except wait for that.
512 * We have successfully authenticated ourselves with the peer using `protocol'.
515 auth_withpeer_success(unit, protocol)
525 if (passwd_from_file)
526 BZERO(passwd, MAXSECRETLEN);
530 warn("auth_withpeer_success: unknown protocol %x", protocol);
535 * If there is no more authentication still being done,
536 * proceed to the network (or callback) phase.
538 if ((auth_pending[unit] &= ~bit) == 0)
544 * np_up - a network protocol has come up.
550 if (num_np_up == 0) {
552 * At this point we consider that the link has come up successfully.
556 if (idle_time_limit > 0)
557 TIMEOUT(check_idle, NULL, idle_time_limit);
560 * Set a timeout to close the connection once the maximum
561 * connect time has expired.
564 TIMEOUT(connect_time_expired, 0, maxconnect);
567 * Detach now, if the updetach option was given.
569 if (updetach && !nodetach)
576 * np_down - a network protocol has gone down.
582 if (--num_np_up == 0 && idle_time_limit > 0) {
583 UNTIMEOUT(check_idle, NULL);
588 * np_finished - a network protocol has finished using the link.
591 np_finished(unit, proto)
594 if (--num_np_open <= 0) {
595 /* no further use for the link: shut up shop. */
596 lcp_close(0, "No network protocols running");
601 * check_idle - check whether the link has been idle for long
602 * enough that we can shut it down.
608 struct ppp_idle idle;
611 if (!get_idle_time(0, &idle))
613 itime = MIN(idle.xmit_idle, idle.recv_idle);
614 if (itime >= idle_time_limit) {
615 /* link is idle: shut it down. */
616 info("Terminating connection due to lack of activity.");
617 lcp_close(0, "Link inactive");
619 TIMEOUT(check_idle, NULL, idle_time_limit - itime);
624 * connect_time_expired - log a message and close the connection.
627 connect_time_expired(arg)
630 info("Connect time expired");
631 lcp_close(0, "Connect time expired"); /* Close connection */
635 * auth_check_options - called to check authentication options.
640 lcp_options *wo = &lcp_wantoptions[0];
642 ipcp_options *ipwo = &ipcp_wantoptions[0];
645 /* Default our_name to hostname, and user to our_name */
646 if (our_name[0] == 0 || usehostname)
647 strlcpy(our_name, sizeof(our_name), hostname);
649 strlcpy(user, sizeof(user), our_name);
651 /* If authentication is required, ask peer for CHAP or PAP. */
653 if (!wo->neg_chap && !wo->neg_upap) {
663 * If we have a default route, require the peer to authenticate
664 * unless the noauth option was given.
666 if (!auth_required && !allow_any_ip && have_route_to(0))
670 * Check whether we have appropriate secrets to use
671 * to authenticate the peer.
673 can_auth = wo->neg_upap && (uselogin || have_pap_secret());
674 if (!can_auth && wo->neg_chap) {
675 remote = ipwo->accept_remote? 0: ipwo->hisaddr;
676 can_auth = have_chap_secret(remote_name, our_name, remote);
679 if (auth_required && !can_auth) {
680 option_error("peer authentication required but no suitable secret(s) found\n");
681 if (remote_name[0] == 0)
682 option_error("for authenticating any peer to us (%s)\n", our_name);
684 option_error("for authenticating peer %s to us (%s)\n",
685 remote_name, our_name);
691 * auth_reset - called when LCP is starting negotiations to recheck
692 * authentication options, i.e. whether we have appropriate secrets
693 * to use for authenticating ourselves and/or the peer.
699 lcp_options *go = &lcp_gotoptions[unit];
700 lcp_options *ao = &lcp_allowoptions[0];
701 ipcp_options *ipwo = &ipcp_wantoptions[0];
704 ao->neg_upap = !refuse_pap && (passwd[0] != 0 || get_pap_passwd(NULL));
705 ao->neg_chap = !refuse_chap
706 && have_chap_secret(user, remote_name, (u_int32_t)0);
708 if (go->neg_upap && !uselogin && !have_pap_secret())
711 remote = ipwo->accept_remote? 0: ipwo->hisaddr;
712 if (!have_chap_secret(remote_name, our_name, remote))
719 * check_passwd - Check the user name and passwd against the PAP secrets
720 * file. If requested, also check against the system password database,
721 * and login the user if OK.
724 * UPAP_AUTHNAK: Authentication failed.
725 * UPAP_AUTHACK: Authentication succeeded.
726 * In either case, msg points to an appropriate message.
729 check_passwd(unit, auser, userlen, apasswd, passwdlen, msg, msglen)
741 struct wordlist *addrs;
743 ipcp_options *ipwo = &ipcp_wantoptions[unit];
744 char passwd[256], user[256];
745 char secret[MAXWORDLEN];
746 static int attempts = 0;
749 * Make copies of apasswd and auser, then null-terminate them.
751 BCOPY(apasswd, passwd, passwdlen);
752 passwd[passwdlen] = '\0';
753 BCOPY(auser, user, userlen);
754 user[userlen] = '\0';
758 * Open the file of pap secrets and scan for a suitable secret
759 * for authenticating this user.
761 filename = _PATH_UPAPFILE;
764 f = fopen(filename, "r");
766 error("Can't open PAP password file %s: %m", filename);
770 check_access(f, filename);
771 remote = ipwo->accept_remote? 0: ipwo->hisaddr;
772 if (scan_authfile(f, user, our_name, remote,
773 secret, &addrs, filename) < 0
774 || (secret[0] != 0 && (cryptpap || strcmp(passwd, secret) != 0)
775 && strcmp(crypt(passwd, secret), secret) != 0)) {
776 warn("PAP authentication failure for %s", user);
782 if (uselogin && ret == UPAP_AUTHACK) {
783 ret = plogin(user, passwd, msg, msglen);
784 if (ret == UPAP_AUTHNAK) {
785 warn("PAP login failure for %s", user);
789 if (ret == UPAP_AUTHNAK) {
790 if (*msg == (char *) 0)
791 *msg = "Login incorrect";
792 *msglen = strlen(*msg);
794 * Frustrate passwd stealer programs.
795 * Allow 10 tries, but start backing off after 3 (stolen from login).
796 * On 10'th, drop the connection.
798 if (attempts++ >= 10) {
799 warn("%d LOGIN FAILURES ON %s, %s", attempts, devnam, user);
803 sleep((u_int) (attempts - 3) * 5);
805 free_wordlist(addrs);
808 attempts = 0; /* Reset count */
809 if (*msg == (char *) 0)
811 *msglen = strlen(*msg);
812 set_allowed_addrs(unit, addrs);
815 BZERO(passwd, sizeof(passwd));
816 BZERO(secret, sizeof(secret));
822 * This function is needed for PAM.
826 static char *PAM_username = "";
827 static char *PAM_password = "";
829 #ifdef PAM_ESTABLISH_CRED /* new PAM defines :(^ */
830 #define MY_PAM_STRERROR(err_code) (char *) pam_strerror(pamh,err_code)
832 #define MY_PAM_STRERROR(err_code) (char *) pam_strerror(err_code)
835 static int pam_conv (int num_msg,
836 const struct pam_message **msg,
837 struct pam_response **resp,
840 int count = 0, replies = 0;
841 struct pam_response *reply = NULL;
844 for (count = 0; count < num_msg; count++)
846 size += sizeof (struct pam_response);
847 reply = realloc (reply, size); /* ANSI: is malloc() if reply==NULL */
851 switch (msg[count]->msg_style)
853 case PAM_PROMPT_ECHO_ON:
854 reply[replies].resp_retcode = PAM_SUCCESS;
855 reply[replies++].resp = strdup(PAM_username); /* never NULL */
858 case PAM_PROMPT_ECHO_OFF:
859 reply[replies].resp_retcode = PAM_SUCCESS;
860 reply[replies++].resp = strdup(PAM_password); /* never NULL */
864 reply[replies].resp_retcode = PAM_SUCCESS;
865 reply[replies++].resp = NULL;
885 * plogin - Check the user name and password against the system
886 * password database, and login the user if OK.
889 * UPAP_AUTHNAK: Login failed.
890 * UPAP_AUTHACK: Login succeeded.
891 * In either case, msg points to an appropriate message.
895 plogin(user, passwd, msg, msglen)
904 struct pam_conv pam_conversation;
908 * Fill the pam_conversion structure
910 memset (&pam_conversation, '\0', sizeof (struct pam_conv));
911 pam_conversation.conv = &pam_conv;
913 pam_error = pam_start ("ppp", user, &pam_conversation, &pamh);
915 if (pam_error != PAM_SUCCESS) {
916 *msg = MY_PAM_STRERROR (pam_error);
920 * Define the fields for the credintial validation
922 (void) pam_set_item (pamh, PAM_TTY, devnam);
924 PAM_password = passwd;
928 pam_error = pam_authenticate (pamh, PAM_SILENT);
929 if (pam_error == PAM_SUCCESS) {
930 pam_error = pam_acct_mgmt (pamh, PAM_SILENT);
932 /* start a session for this user. Session closed when link ends. */
933 if (pam_error == PAM_SUCCESS)
934 (void) pam_open_session (pamh, PAM_SILENT);
937 *msg = MY_PAM_STRERROR (pam_error);
944 (void) pam_end (pamh, pam_error);
946 if (pam_error != PAM_SUCCESS)
949 * Use the non-PAM methods directly
951 #else /* #ifdef USE_PAM */
958 struct spwd *getspnam();
964 return (UPAP_AUTHNAK);
968 spwd = getspnam(user);
971 /* check the age of the password entry */
972 long now = time(NULL) / 86400L;
974 if ((spwd->sp_expire > 0 && now >= spwd->sp_expire)
975 || ((spwd->sp_max >= 0 && spwd->sp_max < 10000)
976 && spwd->sp_lstchg >= 0
977 && now >= spwd->sp_lstchg + spwd->sp_max)) {
978 warn("Password for %s has expired", user);
979 return (UPAP_AUTHNAK);
981 pw->pw_passwd = spwd->sp_pwdp;
986 * If no passwd, don't let them login.
988 if (pw->pw_passwd == NULL || *pw->pw_passwd == '\0'
989 || strcmp(crypt(passwd, pw->pw_passwd), pw->pw_passwd) != 0)
990 return (UPAP_AUTHNAK);
992 /* These functions are not enabled for PAM. The reason for this is that */
993 /* there is not necessarily a "passwd" entry for this user. That is */
994 /* real purpose of 'PAM' -- to virtualize the account data from the */
995 /* application. If you want to do the same thing, write the entry in */
996 /* the 'session' hook. */
999 * Write a wtmp entry for this user.
1003 if (strncmp(tty, "/dev/", 5) == 0)
1005 logwtmp(tty, user, remote_name); /* Add wtmp login entry */
1007 #if defined(_PATH_LASTLOG)
1012 if ((fd = open(_PATH_LASTLOG, O_RDWR, 0)) >= 0) {
1013 (void)lseek(fd, (off_t)(pw->pw_uid * sizeof(ll)), SEEK_SET);
1014 memset((void *)&ll, 0, sizeof(ll));
1015 (void)time(&ll.ll_time);
1016 (void)strlcpy(ll.ll_line, sizeof(ll.ll_line), tty);
1017 (void)write(fd, (char *)&ll, sizeof(ll));
1023 #endif /* #ifdef USE_PAM */
1025 info("user %s logged in", user);
1028 return (UPAP_AUTHACK);
1032 * plogout - Logout the user.
1038 struct pam_conv pam_conversation;
1042 * Fill the pam_conversion structure. The PAM specification states that the
1043 * session must be able to be closed by a totally different handle from which
1044 * it was created. Hold the PAM group to their own specification!
1046 memset (&pam_conversation, '\0', sizeof (struct pam_conv));
1047 pam_conversation.conv = &pam_conv;
1049 pam_error = pam_start ("ppp", user, &pam_conversation, &pamh);
1050 if (pam_error == PAM_SUCCESS) {
1051 (void) pam_set_item (pamh, PAM_TTY, devnam);
1052 (void) pam_close_session (pamh, PAM_SILENT);
1053 (void) pam_end (pamh, PAM_SUCCESS);
1060 if (strncmp(tty, "/dev/", 5) == 0)
1062 logwtmp(tty, "", ""); /* Wipe out utmp logout entry */
1070 * null_login - Check if a username of "" and a password of "" are
1071 * acceptable, and iff so, set the list of acceptable IP addresses
1081 struct wordlist *addrs;
1082 char secret[MAXWORDLEN];
1085 * Open the file of pap secrets and scan for a suitable secret.
1086 * We don't accept a wildcard client.
1088 filename = _PATH_UPAPFILE;
1090 f = fopen(filename, "r");
1093 check_access(f, filename);
1095 i = scan_authfile(f, "", our_name, (u_int32_t)0, secret, &addrs, filename);
1096 ret = i >= 0 && (i & NONWILD_CLIENT) != 0 && secret[0] == 0;
1097 BZERO(secret, sizeof(secret));
1100 set_allowed_addrs(unit, addrs);
1102 free_wordlist(addrs);
1110 * get_pap_passwd - get a password for authenticating ourselves with
1111 * our peer using PAP. Returns 1 on success, 0 if no suitable password
1113 * Assumes passwd points to MAXSECRETLEN bytes of space (if non-null).
1116 get_pap_passwd(passwd)
1122 struct wordlist *addrs;
1123 char secret[MAXWORDLEN];
1125 filename = _PATH_UPAPFILE;
1127 f = fopen(filename, "r");
1130 check_access(f, filename);
1131 ret = scan_authfile(f, user,
1132 remote_name[0]? remote_name: NULL,
1133 (u_int32_t)0, secret, NULL, filename);
1138 strlcpy(passwd, MAXSECRETLEN, secret);
1139 BZERO(secret, sizeof(secret));
1145 * have_pap_secret - check whether we have a PAP file with any
1146 * secrets that we could possibly use for authenticating the peer.
1154 ipcp_options *ipwo = &ipcp_wantoptions[0];
1157 filename = _PATH_UPAPFILE;
1158 f = fopen(filename, "r");
1162 remote = ipwo->accept_remote? 0: ipwo->hisaddr;
1163 ret = scan_authfile(f, NULL, our_name, remote, NULL, NULL, filename);
1173 * have_chap_secret - check whether we have a CHAP file with a
1174 * secret that we could possibly use for authenticating `client'
1175 * on `server'. Either can be the null string, meaning we don't
1176 * know the identity yet.
1179 have_chap_secret(client, server, remote)
1188 filename = _PATH_CHAPFILE;
1189 f = fopen(filename, "r");
1195 else if (server[0] == 0)
1198 ret = scan_authfile(f, client, server, remote, NULL, NULL, filename);
1208 * get_secret - open the CHAP secret file and return the secret
1209 * for authenticating the given client on the given server.
1210 * (We could be either client or server).
1213 get_secret(unit, client, server, secret, secret_len, save_addrs)
1224 struct wordlist *addrs;
1225 char secbuf[MAXWORDLEN];
1227 filename = _PATH_CHAPFILE;
1231 f = fopen(filename, "r");
1233 error("Can't open chap secret file %s: %m", filename);
1236 check_access(f, filename);
1238 ret = scan_authfile(f, client, server, (u_int32_t)0,
1239 secbuf, &addrs, filename);
1245 set_allowed_addrs(unit, addrs);
1247 len = strlen(secbuf);
1248 if (len > MAXSECRETLEN) {
1249 error("Secret for %s on %s is too long", client, server);
1252 BCOPY(secbuf, secret, len);
1253 BZERO(secbuf, sizeof(secbuf));
1260 * set_allowed_addrs() - set the list of allowed addresses.
1263 set_allowed_addrs(unit, addrs)
1265 struct wordlist *addrs;
1267 if (addresses[unit] != NULL)
1268 free_wordlist(addresses[unit]);
1269 addresses[unit] = addrs;
1272 * If there's only one authorized address we might as well
1273 * ask our peer for that one right away
1275 if (addrs != NULL && addrs->next == NULL) {
1276 char *p = addrs->word;
1277 struct ipcp_options *wo = &ipcp_wantoptions[unit];
1281 if (*p != '!' && *p != '-' && *p != '*' && strchr(p, '/') == NULL) {
1282 hp = gethostbyname(p);
1283 if (hp != NULL && hp->h_addrtype == AF_INET)
1284 a = *(u_int32_t *)hp->h_addr;
1287 if (a != (u_int32_t) -1)
1294 * auth_ip_addr - check whether the peer is authorized to use
1295 * a given IP address. Returns 1 if authorized, 0 otherwise.
1298 auth_ip_addr(unit, addr)
1303 if (addresses[unit] == NULL) {
1305 return 0; /* no addresses authorized */
1306 return allow_any_ip || !have_route_to(addr);
1308 return ip_addr_check(addr, addresses[unit]);
1312 ip_addr_check(addr, addrs)
1314 struct wordlist *addrs;
1316 u_int32_t a, mask, ah;
1318 char *ptr_word, *ptr_mask;
1322 /* don't allow loopback or multicast address */
1323 if (bad_ip_adrs(addr))
1327 return 0; /* no addresses authorized */
1329 for (; addrs != NULL; addrs = addrs->next) {
1330 /* "-" means no addresses authorized, "*" means any address allowed */
1331 ptr_word = addrs->word;
1332 if (strcmp(ptr_word, "-") == 0)
1334 if (strcmp(ptr_word, "*") == 0)
1338 if (*ptr_word == '!') {
1343 mask = ~ (u_int32_t) 0;
1344 ptr_mask = strchr (ptr_word, '/');
1345 if (ptr_mask != NULL) {
1348 bit_count = (int) strtol (ptr_mask+1, (char **) 0, 10);
1349 if (bit_count <= 0 || bit_count > 32) {
1350 warn("invalid address length %v in auth. address list",
1355 mask <<= 32 - bit_count;
1358 hp = gethostbyname(ptr_word);
1359 if (hp != NULL && hp->h_addrtype == AF_INET) {
1360 a = *(u_int32_t *)hp->h_addr;
1362 np = getnetbyname (ptr_word);
1363 if (np != NULL && np->n_addrtype == AF_INET) {
1364 a = htonl (*(u_int32_t *)np->n_net);
1365 if (ptr_mask == NULL) {
1366 /* calculate appropriate mask for net */
1369 mask = IN_CLASSA_NET;
1370 else if (IN_CLASSB(ah))
1371 mask = IN_CLASSB_NET;
1372 else if (IN_CLASSC(ah))
1373 mask = IN_CLASSC_NET;
1376 a = inet_addr (ptr_word);
1380 if (ptr_mask != NULL)
1383 if (a == (u_int32_t)-1L)
1384 warn("unknown host %s in auth. address list", addrs->word);
1386 /* Here a and addr are in network byte order,
1387 and mask is in host order. */
1388 if (((addr ^ a) & htonl(mask)) == 0)
1391 return 0; /* not in list => can't have it */
1395 * bad_ip_adrs - return 1 if the IP address is one we don't want
1396 * to use, such as an address in the loopback net or a multicast address.
1397 * addr is in network byte order.
1404 return (addr >> IN_CLASSA_NSHIFT) == IN_LOOPBACKNET
1405 || IN_MULTICAST(addr) || IN_BADCLASS(addr);
1409 * check_access - complain if a secret file has too-liberal permissions.
1412 check_access(f, filename)
1418 if (fstat(fileno(f), &sbuf) < 0) {
1419 warn("cannot stat secret file %s: %m", filename);
1420 } else if ((sbuf.st_mode & (S_IRWXG | S_IRWXO)) != 0) {
1421 warn("Warning - secret file %s has world and/or group access",
1428 * scan_authfile - Scan an authorization file for a secret suitable
1429 * for authenticating `client' on `server'. The return value is -1
1430 * if no secret is found, otherwise >= 0. The return value has
1431 * NONWILD_CLIENT set if the secret didn't have "*" for the client, and
1432 * NONWILD_SERVER set if the secret didn't have "*" for the server.
1433 * Any following words on the line (i.e. address authorization
1434 * info) are placed in a wordlist and returned in *addrs.
1435 * We assume secret is NULL or points to MAXWORDLEN bytes of space.
1438 scan_authfile(f, client, server, ipaddr, secret, addrs, filename)
1444 struct wordlist **addrs;
1448 int got_flag, best_flag;
1450 struct wordlist *ap, *addr_list, *alist, *alast;
1451 char word[MAXWORDLEN];
1452 char atfile[MAXWORDLEN];
1453 char lsecret[MAXWORDLEN];
1458 if (!getword(f, word, &newline, filename))
1459 return -1; /* file is empty??? */
1464 * Skip until we find a word at the start of a line.
1466 while (!newline && getword(f, word, &newline, filename))
1469 break; /* got to end of file */
1472 * Got a client - check if it's a match or a wildcard.
1475 if (client != NULL && strcmp(word, client) != 0 && !ISWILD(word)) {
1480 got_flag = NONWILD_CLIENT;
1483 * Now get a server and check if it matches.
1485 if (!getword(f, word, &newline, filename))
1489 if (server != NULL && strcmp(word, server) != 0 && !ISWILD(word))
1492 got_flag |= NONWILD_SERVER;
1495 * Got some sort of a match - see if it's better than what
1498 if (got_flag <= best_flag)
1504 if (!getword(f, word, &newline, filename))
1510 * Special syntax: @filename means read secret from file.
1512 if (word[0] == '@') {
1513 strlcpy(atfile, sizeof(atfile), word+1);
1514 if ((sf = fopen(atfile, "r")) == NULL) {
1515 warn("can't open indirect secret file %s", atfile);
1518 check_access(sf, atfile);
1519 if (!getword(sf, word, &xxx, atfile)) {
1520 warn("no secret in indirect secret file %s", atfile);
1527 strlcpy(lsecret, sizeof(lsecret), word);
1530 * Now read address authorization info and make a wordlist.
1532 alist = alast = NULL;
1534 if (!getword(f, word, &newline, filename) || newline)
1536 ap = (struct wordlist *) malloc(sizeof(struct wordlist));
1538 novm("authorized addresses");
1540 ap->word = strdup(word);
1541 if (ap->word == NULL)
1542 novm("authorized address");
1551 * Check if the given IP address is allowed by the wordlist.
1552 * XXX accepts this entry even if it has no allowed IP addresses
1553 * if they didn't specify a remote IP address. XXX
1555 if (ipaddr != 0 && !ip_addr_check(ipaddr, alist)) {
1556 free_wordlist(alist);
1561 * This is the best so far; remember it.
1563 best_flag = got_flag;
1565 free_wordlist(addr_list);
1568 strlcpy(secret, MAXWORDLEN, lsecret);
1576 else if (addr_list != NULL)
1577 free_wordlist(addr_list);
1583 * free_wordlist - release memory allocated for a wordlist.
1587 struct wordlist *wp;
1589 struct wordlist *next;
1591 while (wp != NULL) {
1599 * auth_script - execute a script with arguments
1600 * interface-name peer-name real-user tty speed
1612 if ((pw = getpwuid(getuid())) != NULL && pw->pw_name != NULL)
1613 user_name = pw->pw_name;
1615 slprintf(struid, sizeof(struid), "%d", getuid());
1618 slprintf(strspeed, sizeof(strspeed), "%d", baud_rate);
1622 argv[2] = peer_authname;
1623 argv[3] = user_name;
1628 authup_pid = run_program(script, argv, 0, NULL, NULL);