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 1.40 1999/01/19 23:59:14 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 *));
159 static int setupapfile __P((char **));
163 * Authentication-related options.
165 option_t auth_options[] = {
166 { "require-pap", o_bool, &lcp_wantoptions[0].neg_upap,
167 "Require PAP authentication from peer", 1, &auth_required },
168 { "+pap", o_bool, &lcp_wantoptions[0].neg_upap,
169 "Require PAP authentication from peer", 1, &auth_required },
170 { "refuse-pap", o_bool, &refuse_pap,
171 "Don't agree to auth to peer with PAP", 1 },
172 { "-pap", o_bool, &refuse_pap,
173 "Don't allow UPAP authentication with peer", 1 },
174 { "require-chap", o_bool, &lcp_wantoptions[0].neg_chap,
175 "Require CHAP authentication from peer", 1, &auth_required },
176 { "+chap", o_bool, &lcp_wantoptions[0].neg_chap,
177 "Require CHAP authentication from peer", 1, &auth_required },
178 { "refuse-chap", o_bool, &refuse_chap,
179 "Don't agree to auth to peer with CHAP", 1 },
180 { "-chap", o_bool, &refuse_chap,
181 "Don't allow CHAP authentication with peer", 1 },
182 { "name", o_string, our_name,
183 "Set local name for authentication",
184 OPT_PRIV|OPT_STATIC, NULL, MAXNAMELEN },
185 { "user", o_string, user,
186 "Set name for auth with peer", OPT_STATIC, NULL, MAXNAMELEN },
187 { "usehostname", o_bool, &usehostname,
188 "Must use hostname for authentication", 1 },
189 { "remotename", o_string, remote_name,
190 "Set remote name for authentication", OPT_STATIC, NULL, MAXNAMELEN },
191 { "auth", o_bool, &auth_required,
192 "Require authentication from peer", 1 },
193 { "noauth", o_bool, &auth_required,
194 "Don't require peer to authenticate", OPT_PRIV, &allow_any_ip },
195 { "login", o_bool, &uselogin,
196 "Use system password database for PAP", 1 },
197 { "papcrypt", o_bool, &cryptpap,
198 "PAP passwords are encrypted", 1 },
200 { "+ua", o_special, setupapfile,
201 "Get PAP user and password from file" },
208 * setupapfile - specifies UPAP info for authenticating with peer.
217 lcp_allowoptions[0].neg_upap = 1;
219 /* open user info file */
220 if ((ufile = fopen(*argv, "r")) == NULL) {
221 option_error("unable to open user login data file %s", *argv);
224 if (!readable(fileno(ufile))) {
225 option_error("%s: access denied", *argv);
228 check_access(ufile, *argv);
231 if (fgets(user, MAXNAMELEN - 1, ufile) == NULL
232 || fgets(passwd, MAXSECRETLEN - 1, ufile) == NULL){
233 option_error("unable to read user login data file %s", *argv);
238 /* get rid of newlines */
240 if (l > 0 && user[l-1] == '\n')
243 if (l > 0 && passwd[l-1] == '\n')
252 * An Open on LCP has requested a change from Dead to Establish phase.
253 * Do what's necessary to bring the physical layer up.
262 * LCP has terminated the link; go to the Dead phase and take the
263 * physical layer down.
266 link_terminated(unit)
269 if (phase == PHASE_DEAD)
274 syslog(LOG_NOTICE, "Connection terminated.");
278 * LCP has gone down; it will either die or try to re-establish.
285 struct protent *protp;
288 auth_script(_PATH_AUTHDOWN);
291 for (i = 0; (protp = protocols[i]) != NULL; ++i) {
292 if (!protp->enabled_flag)
294 if (protp->protocol != PPP_LCP && protp->lowerdown != NULL)
295 (*protp->lowerdown)(unit);
296 if (protp->protocol < 0xC000 && protp->close != NULL)
297 (*protp->close)(unit, "LCP down");
301 if (phase != PHASE_DEAD)
302 phase = PHASE_TERMINATE;
306 * The link is established.
307 * Proceed to the Dead, Authenticate or Network phase as appropriate.
310 link_established(unit)
314 lcp_options *wo = &lcp_wantoptions[unit];
315 lcp_options *go = &lcp_gotoptions[unit];
316 lcp_options *ho = &lcp_hisoptions[unit];
318 struct protent *protp;
321 * Tell higher-level protocols that LCP is up.
323 for (i = 0; (protp = protocols[i]) != NULL; ++i)
324 if (protp->protocol != PPP_LCP && protp->enabled_flag
325 && protp->lowerup != NULL)
326 (*protp->lowerup)(unit);
328 if (auth_required && !(go->neg_chap || go->neg_upap)) {
330 * We wanted the peer to authenticate itself, and it refused:
331 * treat it as though it authenticated with PAP using a username
332 * of "" and a password of "". If that's not OK, boot it out.
334 if (!wo->neg_upap || !null_login(unit)) {
335 syslog(LOG_WARNING, "peer refused to authenticate");
336 lcp_close(unit, "peer refused to authenticate");
341 phase = PHASE_AUTHENTICATE;
344 ChapAuthPeer(unit, our_name, go->chap_mdtype);
346 } else if (go->neg_upap) {
351 ChapAuthWithPeer(unit, user, ho->chap_mdtype);
352 auth |= CHAP_WITHPEER;
353 } else if (ho->neg_upap) {
354 if (passwd[0] == 0) {
355 passwd_from_file = 1;
356 if (!get_pap_passwd(passwd))
357 syslog(LOG_ERR, "No secret found for PAP login");
359 upap_authwithpeer(unit, user, passwd);
360 auth |= PAP_WITHPEER;
362 auth_pending[unit] = auth;
369 * Proceed to the network phase.
376 struct protent *protp;
377 lcp_options *go = &lcp_gotoptions[unit];
380 * If the peer had to authenticate, run the auth-up script now.
382 if ((go->neg_chap || go->neg_upap) && !did_authup) {
383 auth_script(_PATH_AUTHUP);
389 * If we negotiated callback, do it now.
392 phase = PHASE_CALLBACK;
393 (*cbcp_protent.open)(unit);
398 phase = PHASE_NETWORK;
401 set_filters(&pass_filter, &active_filter);
403 for (i = 0; (protp = protocols[i]) != NULL; ++i)
404 if (protp->protocol < 0xC000 && protp->enabled_flag
405 && protp->open != NULL) {
406 (*protp->open)(unit);
407 if (protp->protocol != PPP_CCP)
411 if (num_np_open == 0)
413 lcp_close(0, "No network protocols running");
417 * The peer has failed to authenticate himself using `protocol'.
420 auth_peer_fail(unit, protocol)
424 * Authentication failure: take the link down
426 lcp_close(unit, "Authentication failed");
430 * The peer has been successfully authenticated using `protocol'.
433 auth_peer_success(unit, protocol, name, namelen)
448 syslog(LOG_WARNING, "auth_peer_success: unknown protocol %x",
454 * Save the authenticated name of the peer for later.
456 if (namelen > sizeof(peer_authname) - 1)
457 namelen = sizeof(peer_authname) - 1;
458 BCOPY(name, peer_authname, namelen);
459 peer_authname[namelen] = 0;
460 script_setenv("PEERNAME", peer_authname);
463 * If there is no more authentication still to be done,
464 * proceed to the network (or callback) phase.
466 if ((auth_pending[unit] &= ~bit) == 0)
471 * We have failed to authenticate ourselves to the peer using `protocol'.
474 auth_withpeer_fail(unit, protocol)
477 if (passwd_from_file)
478 BZERO(passwd, MAXSECRETLEN);
480 * We've failed to authenticate ourselves to our peer.
481 * He'll probably take the link down, and there's not much
482 * we can do except wait for that.
487 * We have successfully authenticated ourselves with the peer using `protocol'.
490 auth_withpeer_success(unit, protocol)
500 if (passwd_from_file)
501 BZERO(passwd, MAXSECRETLEN);
505 syslog(LOG_WARNING, "auth_peer_success: unknown protocol %x",
511 * If there is no more authentication still being done,
512 * proceed to the network (or callback) phase.
514 if ((auth_pending[unit] &= ~bit) == 0)
520 * np_up - a network protocol has come up.
526 if (num_np_up == 0) {
528 * At this point we consider that the link has come up successfully.
532 if (idle_time_limit > 0)
533 TIMEOUT(check_idle, NULL, idle_time_limit);
536 * Set a timeout to close the connection once the maximum
537 * connect time has expired.
540 TIMEOUT(connect_time_expired, 0, maxconnect);
543 * Detach now, if the updetach option was given.
545 if (updetach && !nodetach)
552 * np_down - a network protocol has gone down.
558 if (--num_np_up == 0 && idle_time_limit > 0) {
559 UNTIMEOUT(check_idle, NULL);
564 * np_finished - a network protocol has finished using the link.
567 np_finished(unit, proto)
570 if (--num_np_open <= 0) {
571 /* no further use for the link: shut up shop. */
572 lcp_close(0, "No network protocols running");
577 * check_idle - check whether the link has been idle for long
578 * enough that we can shut it down.
584 struct ppp_idle idle;
587 if (!get_idle_time(0, &idle))
589 itime = MIN(idle.xmit_idle, idle.recv_idle);
590 if (itime >= idle_time_limit) {
591 /* link is idle: shut it down. */
592 syslog(LOG_INFO, "Terminating connection due to lack of activity.");
593 lcp_close(0, "Link inactive");
595 TIMEOUT(check_idle, NULL, idle_time_limit - itime);
600 * connect_time_expired - log a message and close the connection.
603 connect_time_expired(arg)
606 syslog(LOG_INFO, "Connect time expired");
607 lcp_close(0, "Connect time expired"); /* Close connection */
611 * auth_check_options - called to check authentication options.
616 lcp_options *wo = &lcp_wantoptions[0];
618 ipcp_options *ipwo = &ipcp_wantoptions[0];
621 /* Default our_name to hostname, and user to our_name */
622 if (our_name[0] == 0 || usehostname)
623 strcpy(our_name, hostname);
625 strcpy(user, our_name);
627 /* If authentication is required, ask peer for CHAP or PAP. */
629 if (!wo->neg_chap && !wo->neg_upap) {
639 * Check whether we have appropriate secrets to use
640 * to authenticate the peer.
642 can_auth = wo->neg_upap && (uselogin || have_pap_secret());
643 if (!can_auth && wo->neg_chap) {
644 remote = ipwo->accept_remote? 0: ipwo->hisaddr;
645 can_auth = have_chap_secret(remote_name, our_name, remote);
648 if (auth_required && !can_auth) {
649 option_error("peer authentication required but no suitable secret(s) found\n");
650 if (remote_name[0] == 0)
651 option_error("for authenticating any peer to us (%s)\n", our_name);
653 option_error("for authenticating peer %s to us (%s)\n",
654 remote_name, our_name);
659 * Check whether the user tried to override certain values
663 if ((connector != NULL && connector_info.priv == 0)
664 || (disconnector != NULL && disconnector_info.priv == 0)
665 || (welcomer != NULL && welcomer_info.priv == 0)) {
666 option_error("connect, disconnect and welcome options");
667 option_error("are privileged when noauth option is used");
674 * auth_reset - called when LCP is starting negotiations to recheck
675 * authentication options, i.e. whether we have appropriate secrets
676 * to use for authenticating ourselves and/or the peer.
682 lcp_options *go = &lcp_gotoptions[unit];
683 lcp_options *ao = &lcp_allowoptions[0];
684 ipcp_options *ipwo = &ipcp_wantoptions[0];
687 ao->neg_upap = !refuse_pap && (passwd[0] != 0 || get_pap_passwd(NULL));
688 ao->neg_chap = !refuse_chap
689 && have_chap_secret(user, remote_name, (u_int32_t)0);
691 if (go->neg_upap && !uselogin && !have_pap_secret())
694 remote = ipwo->accept_remote? 0: ipwo->hisaddr;
695 if (!have_chap_secret(remote_name, our_name, remote))
702 * check_passwd - Check the user name and passwd against the PAP secrets
703 * file. If requested, also check against the system password database,
704 * and login the user if OK.
707 * UPAP_AUTHNAK: Authentication failed.
708 * UPAP_AUTHACK: Authentication succeeded.
709 * In either case, msg points to an appropriate message.
712 check_passwd(unit, auser, userlen, apasswd, passwdlen, msg, msglen)
724 struct wordlist *addrs;
726 ipcp_options *ipwo = &ipcp_wantoptions[unit];
727 char passwd[256], user[256];
728 char secret[MAXWORDLEN];
729 static int attempts = 0;
732 * Make copies of apasswd and auser, then null-terminate them.
734 BCOPY(apasswd, passwd, passwdlen);
735 passwd[passwdlen] = '\0';
736 BCOPY(auser, user, userlen);
737 user[userlen] = '\0';
741 * Open the file of pap secrets and scan for a suitable secret
742 * for authenticating this user.
744 filename = _PATH_UPAPFILE;
747 f = fopen(filename, "r");
749 syslog(LOG_ERR, "Can't open PAP password file %s: %m", filename);
753 check_access(f, filename);
754 remote = ipwo->accept_remote? 0: ipwo->hisaddr;
755 if (scan_authfile(f, user, our_name, remote,
756 secret, &addrs, filename) < 0
757 || (secret[0] != 0 && (cryptpap || strcmp(passwd, secret) != 0)
758 && strcmp(crypt(passwd, secret), secret) != 0)) {
759 syslog(LOG_WARNING, "PAP authentication failure for %s", user);
765 if (uselogin && ret == UPAP_AUTHACK) {
766 ret = plogin(user, passwd, msg, msglen);
767 if (ret == UPAP_AUTHNAK) {
768 syslog(LOG_WARNING, "PAP login failure for %s", user);
772 if (ret == UPAP_AUTHNAK) {
773 if (*msg == (char *) 0)
774 *msg = "Login incorrect";
775 *msglen = strlen(*msg);
777 * Frustrate passwd stealer programs.
778 * Allow 10 tries, but start backing off after 3 (stolen from login).
779 * On 10'th, drop the connection.
781 if (attempts++ >= 10) {
782 syslog(LOG_WARNING, "%d LOGIN FAILURES ON %s, %s",
783 attempts, devnam, user);
787 sleep((u_int) (attempts - 3) * 5);
789 free_wordlist(addrs);
792 attempts = 0; /* Reset count */
793 if (*msg == (char *) 0)
795 *msglen = strlen(*msg);
796 set_allowed_addrs(unit, addrs);
799 BZERO(passwd, sizeof(passwd));
800 BZERO(secret, sizeof(secret));
806 * This function is needed for PAM.
810 static char *PAM_username = "";
811 static char *PAM_password = "";
813 #ifdef PAM_ESTABLISH_CRED /* new PAM defines :(^ */
814 #define MY_PAM_STRERROR(err_code) (char *) pam_strerror(pamh,err_code)
816 #define MY_PAM_STRERROR(err_code) (char *) pam_strerror(err_code)
819 static int pam_conv (int num_msg,
820 const struct pam_message **msg,
821 struct pam_response **resp,
824 int count = 0, replies = 0;
825 struct pam_response *reply = NULL;
828 for (count = 0; count < num_msg; count++)
830 size += sizeof (struct pam_response);
831 reply = realloc (reply, size); /* ANSI: is malloc() if reply==NULL */
835 switch (msg[count]->msg_style)
837 case PAM_PROMPT_ECHO_ON:
838 reply[replies].resp_retcode = PAM_SUCCESS;
839 reply[replies++].resp = strdup(PAM_username); /* never NULL */
842 case PAM_PROMPT_ECHO_OFF:
843 reply[replies].resp_retcode = PAM_SUCCESS;
844 reply[replies++].resp = strdup(PAM_password); /* never NULL */
848 reply[replies].resp_retcode = PAM_SUCCESS;
849 reply[replies++].resp = NULL;
869 * plogin - Check the user name and password against the system
870 * password database, and login the user if OK.
873 * UPAP_AUTHNAK: Login failed.
874 * UPAP_AUTHACK: Login succeeded.
875 * In either case, msg points to an appropriate message.
879 plogin(user, passwd, msg, msglen)
888 struct pam_conv pam_conversation;
892 * Fill the pam_conversion structure
894 memset (&pam_conversation, '\0', sizeof (struct pam_conv));
895 pam_conversation.conv = &pam_conv;
897 pam_error = pam_start ("ppp", user, &pam_conversation, &pamh);
899 if (pam_error != PAM_SUCCESS) {
900 *msg = MY_PAM_STRERROR (pam_error);
904 * Define the fields for the credintial validation
906 (void) pam_set_item (pamh, PAM_TTY, devnam);
908 PAM_password = passwd;
912 pam_error = pam_authenticate (pamh, PAM_SILENT);
913 if (pam_error == PAM_SUCCESS) {
914 pam_error = pam_acct_mgmt (pamh, PAM_SILENT);
916 /* start a session for this user. Session closed when link ends. */
917 if (pam_error == PAM_SUCCESS)
918 (void) pam_open_session (pamh, PAM_SILENT);
921 *msg = MY_PAM_STRERROR (pam_error);
928 (void) pam_end (pamh, pam_error);
930 if (pam_error != PAM_SUCCESS)
933 * Use the non-PAM methods directly
935 #else /* #ifdef USE_PAM */
942 struct spwd *getspnam();
948 return (UPAP_AUTHNAK);
952 spwd = getspnam(user);
955 /* check the age of the password entry */
956 long now = time(NULL) / 86400L;
958 if ((spwd->sp_expire > 0 && now >= spwd->sp_expire)
959 || ((spwd->sp_max >= 0 && spwd->sp_max < 10000)
960 && spwd->sp_lstchg >= 0
961 && now >= spwd->sp_lstchg + spwd->sp_max)) {
962 syslog(LOG_WARNING, "Password for %s has expired", user);
963 return (UPAP_AUTHNAK);
965 pw->pw_passwd = spwd->sp_pwdp;
970 * If no passwd, don't let them login.
972 if (pw->pw_passwd == NULL || *pw->pw_passwd == '\0'
973 || strcmp(crypt(passwd, pw->pw_passwd), pw->pw_passwd) != 0)
974 return (UPAP_AUTHNAK);
976 /* These functions are not enabled for PAM. The reason for this is that */
977 /* there is not necessarily a "passwd" entry for this user. That is */
978 /* real purpose of 'PAM' -- to virtualize the account data from the */
979 /* application. If you want to do the same thing, write the entry in */
980 /* the 'session' hook. */
983 * Write a wtmp entry for this user.
987 if (strncmp(tty, "/dev/", 5) == 0)
989 logwtmp(tty, user, remote_name); /* Add wtmp login entry */
991 #if defined(_PATH_LASTLOG)
996 if ((fd = open(_PATH_LASTLOG, O_RDWR, 0)) >= 0) {
997 (void)lseek(fd, (off_t)(pw->pw_uid * sizeof(ll)), SEEK_SET);
998 memset((void *)&ll, 0, sizeof(ll));
999 (void)time(&ll.ll_time);
1000 (void)strncpy(ll.ll_line, tty, sizeof(ll.ll_line));
1001 (void)write(fd, (char *)&ll, sizeof(ll));
1007 #endif /* #ifdef USE_PAM */
1009 syslog(LOG_INFO, "user %s logged in", user);
1012 return (UPAP_AUTHACK);
1016 * plogout - Logout the user.
1022 struct pam_conv pam_conversation;
1026 * Fill the pam_conversion structure. The PAM specification states that the
1027 * session must be able to be closed by a totally different handle from which
1028 * it was created. Hold the PAM group to their own specification!
1030 memset (&pam_conversation, '\0', sizeof (struct pam_conv));
1031 pam_conversation.conv = &pam_conv;
1033 pam_error = pam_start ("ppp", user, &pam_conversation, &pamh);
1034 if (pam_error == PAM_SUCCESS) {
1035 (void) pam_set_item (pamh, PAM_TTY, devnam);
1036 (void) pam_close_session (pamh, PAM_SILENT);
1037 (void) pam_end (pamh, PAM_SUCCESS);
1044 if (strncmp(tty, "/dev/", 5) == 0)
1046 logwtmp(tty, "", ""); /* Wipe out utmp logout entry */
1054 * null_login - Check if a username of "" and a password of "" are
1055 * acceptable, and iff so, set the list of acceptable IP addresses
1065 struct wordlist *addrs;
1066 char secret[MAXWORDLEN];
1069 * Open the file of pap secrets and scan for a suitable secret.
1070 * We don't accept a wildcard client.
1072 filename = _PATH_UPAPFILE;
1074 f = fopen(filename, "r");
1077 check_access(f, filename);
1079 i = scan_authfile(f, "", our_name, (u_int32_t)0, secret, &addrs, filename);
1080 ret = i >= 0 && (i & NONWILD_CLIENT) != 0 && secret[0] == 0;
1081 BZERO(secret, sizeof(secret));
1084 set_allowed_addrs(unit, addrs);
1086 free_wordlist(addrs);
1094 * get_pap_passwd - get a password for authenticating ourselves with
1095 * our peer using PAP. Returns 1 on success, 0 if no suitable password
1099 get_pap_passwd(passwd)
1105 struct wordlist *addrs;
1106 char secret[MAXWORDLEN];
1108 filename = _PATH_UPAPFILE;
1110 f = fopen(filename, "r");
1113 check_access(f, filename);
1114 ret = scan_authfile(f, user,
1115 remote_name[0]? remote_name: NULL,
1116 (u_int32_t)0, secret, NULL, filename);
1120 if (passwd != NULL) {
1121 strncpy(passwd, secret, MAXSECRETLEN);
1122 passwd[MAXSECRETLEN-1] = 0;
1124 BZERO(secret, sizeof(secret));
1130 * have_pap_secret - check whether we have a PAP file with any
1131 * secrets that we could possibly use for authenticating the peer.
1139 ipcp_options *ipwo = &ipcp_wantoptions[0];
1142 filename = _PATH_UPAPFILE;
1143 f = fopen(filename, "r");
1147 remote = ipwo->accept_remote? 0: ipwo->hisaddr;
1148 ret = scan_authfile(f, NULL, our_name, remote, NULL, NULL, filename);
1158 * have_chap_secret - check whether we have a CHAP file with a
1159 * secret that we could possibly use for authenticating `client'
1160 * on `server'. Either can be the null string, meaning we don't
1161 * know the identity yet.
1164 have_chap_secret(client, server, remote)
1173 filename = _PATH_CHAPFILE;
1174 f = fopen(filename, "r");
1180 else if (server[0] == 0)
1183 ret = scan_authfile(f, client, server, remote, NULL, NULL, filename);
1193 * get_secret - open the CHAP secret file and return the secret
1194 * for authenticating the given client on the given server.
1195 * (We could be either client or server).
1198 get_secret(unit, client, server, secret, secret_len, save_addrs)
1209 struct wordlist *addrs;
1210 char secbuf[MAXWORDLEN];
1212 filename = _PATH_CHAPFILE;
1216 f = fopen(filename, "r");
1218 syslog(LOG_ERR, "Can't open chap secret file %s: %m", filename);
1221 check_access(f, filename);
1223 ret = scan_authfile(f, client, server, (u_int32_t)0,
1224 secbuf, &addrs, filename);
1230 set_allowed_addrs(unit, addrs);
1232 len = strlen(secbuf);
1233 if (len > MAXSECRETLEN) {
1234 syslog(LOG_ERR, "Secret for %s on %s is too long", client, server);
1237 BCOPY(secbuf, secret, len);
1238 BZERO(secbuf, sizeof(secbuf));
1245 * set_allowed_addrs() - set the list of allowed addresses.
1248 set_allowed_addrs(unit, addrs)
1250 struct wordlist *addrs;
1252 if (addresses[unit] != NULL)
1253 free_wordlist(addresses[unit]);
1254 addresses[unit] = addrs;
1257 * If there's only one authorized address we might as well
1258 * ask our peer for that one right away
1260 if (addrs != NULL && addrs->next == NULL) {
1261 char *p = addrs->word;
1262 struct ipcp_options *wo = &ipcp_wantoptions[unit];
1266 if (*p != '!' && *p != '-' && *p != '*' && strchr(p, '/') == NULL) {
1267 hp = gethostbyname(p);
1268 if (hp != NULL && hp->h_addrtype == AF_INET)
1269 a = *(u_int32_t *)hp->h_addr;
1272 if (a != (u_int32_t) -1)
1279 * auth_ip_addr - check whether the peer is authorized to use
1280 * a given IP address. Returns 1 if authorized, 0 otherwise.
1283 auth_ip_addr(unit, addr)
1287 return ip_addr_check(addr, addresses[unit]);
1291 ip_addr_check(addr, addrs)
1293 struct wordlist *addrs;
1295 u_int32_t a, mask, ah;
1297 char *ptr_word, *ptr_mask;
1301 /* don't allow loopback or multicast address */
1302 if (bad_ip_adrs(addr))
1305 if (addrs == NULL) {
1307 return 0; /* no addresses authorized */
1308 return allow_any_ip || !have_route_to(addr);
1311 for (; addrs != NULL; addrs = addrs->next) {
1312 /* "-" means no addresses authorized, "*" means any address allowed */
1313 ptr_word = addrs->word;
1314 if (strcmp(ptr_word, "-") == 0)
1316 if (strcmp(ptr_word, "*") == 0)
1320 if (*ptr_word == '!') {
1325 mask = ~ (u_int32_t) 0;
1326 ptr_mask = strchr (ptr_word, '/');
1327 if (ptr_mask != NULL) {
1330 bit_count = (int) strtol (ptr_mask+1, (char **) 0, 10);
1331 if (bit_count <= 0 || bit_count > 32) {
1332 syslog (LOG_WARNING,
1333 "invalid address length %s in auth. address list",
1338 mask <<= 32 - bit_count;
1341 hp = gethostbyname(ptr_word);
1342 if (hp != NULL && hp->h_addrtype == AF_INET) {
1343 a = *(u_int32_t *)hp->h_addr;
1345 np = getnetbyname (ptr_word);
1346 if (np != NULL && np->n_addrtype == AF_INET) {
1347 a = htonl (*(u_int32_t *)np->n_net);
1348 if (ptr_mask == NULL) {
1349 /* calculate appropriate mask for net */
1352 mask = IN_CLASSA_NET;
1353 else if (IN_CLASSB(ah))
1354 mask = IN_CLASSB_NET;
1355 else if (IN_CLASSC(ah))
1356 mask = IN_CLASSC_NET;
1359 a = inet_addr (ptr_word);
1363 if (ptr_mask != NULL)
1366 if (a == (u_int32_t)-1L)
1367 syslog (LOG_WARNING,
1368 "unknown host %s in auth. address list",
1371 /* Here a and addr are in network byte order,
1372 and mask is in host order. */
1373 if (((addr ^ a) & htonl(mask)) == 0)
1376 return 0; /* not in list => can't have it */
1380 * bad_ip_adrs - return 1 if the IP address is one we don't want
1381 * to use, such as an address in the loopback net or a multicast address.
1382 * addr is in network byte order.
1389 return (addr >> IN_CLASSA_NSHIFT) == IN_LOOPBACKNET
1390 || IN_MULTICAST(addr) || IN_BADCLASS(addr);
1394 * check_access - complain if a secret file has too-liberal permissions.
1397 check_access(f, filename)
1403 if (fstat(fileno(f), &sbuf) < 0) {
1404 syslog(LOG_WARNING, "cannot stat secret file %s: %m", filename);
1405 } else if ((sbuf.st_mode & (S_IRWXG | S_IRWXO)) != 0) {
1406 syslog(LOG_WARNING, "Warning - secret file %s has world and/or group access", filename);
1412 * scan_authfile - Scan an authorization file for a secret suitable
1413 * for authenticating `client' on `server'. The return value is -1
1414 * if no secret is found, otherwise >= 0. The return value has
1415 * NONWILD_CLIENT set if the secret didn't have "*" for the client, and
1416 * NONWILD_SERVER set if the secret didn't have "*" for the server.
1417 * Any following words on the line (i.e. address authorization
1418 * info) are placed in a wordlist and returned in *addrs.
1421 scan_authfile(f, client, server, ipaddr, secret, addrs, filename)
1427 struct wordlist **addrs;
1431 int got_flag, best_flag;
1433 struct wordlist *ap, *addr_list, *alist, *alast;
1434 char word[MAXWORDLEN];
1435 char atfile[MAXWORDLEN];
1436 char lsecret[MAXWORDLEN];
1441 if (!getword(f, word, &newline, filename))
1442 return -1; /* file is empty??? */
1447 * Skip until we find a word at the start of a line.
1449 while (!newline && getword(f, word, &newline, filename))
1452 break; /* got to end of file */
1455 * Got a client - check if it's a match or a wildcard.
1458 if (client != NULL && strcmp(word, client) != 0 && !ISWILD(word)) {
1463 got_flag = NONWILD_CLIENT;
1466 * Now get a server and check if it matches.
1468 if (!getword(f, word, &newline, filename))
1472 if (server != NULL && strcmp(word, server) != 0 && !ISWILD(word))
1475 got_flag |= NONWILD_SERVER;
1478 * Got some sort of a match - see if it's better than what
1481 if (got_flag <= best_flag)
1487 if (!getword(f, word, &newline, filename))
1493 * Special syntax: @filename means read secret from file.
1495 if (word[0] == '@') {
1496 strcpy(atfile, word+1);
1497 if ((sf = fopen(atfile, "r")) == NULL) {
1498 syslog(LOG_WARNING, "can't open indirect secret file %s",
1502 check_access(sf, atfile);
1503 if (!getword(sf, word, &xxx, atfile)) {
1504 syslog(LOG_WARNING, "no secret in indirect secret file %s",
1512 strcpy(lsecret, word);
1515 * Now read address authorization info and make a wordlist.
1517 alist = alast = NULL;
1519 if (!getword(f, word, &newline, filename) || newline)
1521 ap = (struct wordlist *) malloc(sizeof(struct wordlist)
1524 novm("authorized addresses");
1526 strcpy(ap->word, word);
1535 * Check if the given IP address is allowed by the wordlist.
1537 if (ipaddr != 0 && !ip_addr_check(ipaddr, alist)) {
1538 free_wordlist(alist);
1543 * This is the best so far; remember it.
1545 best_flag = got_flag;
1547 free_wordlist(addr_list);
1550 strcpy(secret, lsecret);
1558 else if (addr_list != NULL)
1559 free_wordlist(addr_list);
1565 * free_wordlist - release memory allocated for a wordlist.
1569 struct wordlist *wp;
1571 struct wordlist *next;
1573 while (wp != NULL) {
1581 * auth_script - execute a script with arguments
1582 * interface-name peer-name real-user tty speed
1594 if ((pw = getpwuid(getuid())) != NULL && pw->pw_name != NULL)
1595 user_name = pw->pw_name;
1597 sprintf(struid, "%d", getuid());
1600 sprintf(strspeed, "%d", baud_rate);
1604 argv[2] = peer_authname;
1605 argv[3] = user_name;
1610 authup_pid = run_program(script, argv, 0, NULL, NULL);