/***************************************************************************** * auth.c - Network Authentication and Phase Control program file. * * Copyright (c) 2003 by Marc Boucher, Services Informatiques (MBSI) inc. * Copyright (c) 1997 by Global Election Systems Inc. All rights reserved. * * The authors hereby grant permission to use, copy, modify, distribute, * and license this software and its documentation for any purpose, provided * that existing copyright notices are retained in all copies and that this * notice and the following disclaimer are included verbatim in any * distributions. No written agreement, license, or royalty fee is required * for any of the authorized uses. * * THIS SOFTWARE IS PROVIDED BY THE CONTRIBUTORS *AS IS* AND ANY EXPRESS OR * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. * IN NO EVENT SHALL THE CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. * ****************************************************************************** * REVISION HISTORY * * 03-01-01 Marc Boucher * Ported to lwIP. * 97-12-08 Guy Lancaster , Global Election Systems Inc. * Ported from public pppd code. *****************************************************************************/ /* * auth.c - PPP authentication and phase control. * * Copyright (c) 1993 The Australian National University. * All rights reserved. * * Redistribution and use in source and binary forms are permitted * provided that the above copyright notice and this paragraph are * duplicated in all such forms and that any documentation, * advertising materials, and other materials related to such * distribution and use acknowledge that the software was developed * by the Australian National University. The name of the University * may not be used to endorse or promote products derived from this * software without specific prior written permission. * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE. * * Copyright (c) 1989 Carnegie Mellon University. * All rights reserved. * * Redistribution and use in source and binary forms are permitted * provided that the above copyright notice and this paragraph are * duplicated in all such forms and that any documentation, * advertising materials, and other materials related to such * distribution and use acknowledge that the software was developed * by Carnegie Mellon University. The name of the * University may not be used to endorse or promote products derived * from this software without specific prior written permission. * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE. */ #include "ppp.h" #if PPP_SUPPORT > 0 #include "fsm.h" #include "lcp.h" #include "pap.h" #include "chap.h" #include "auth.h" #include "ipcp.h" #if CBCP_SUPPORT > 0 #include "cbcp.h" #endif #include "pppdebug.h" /*************************/ /*** LOCAL DEFINITIONS ***/ /*************************/ /* Bits in auth_pending[] */ #define PAP_WITHPEER 1 #define PAP_PEER 2 #define CHAP_WITHPEER 4 #define CHAP_PEER 8 /************************/ /*** LOCAL DATA TYPES ***/ /************************/ /* Used for storing a sequence of words. Usually malloced. */ struct wordlist { struct wordlist *next; char word[1]; }; /***********************************/ /*** LOCAL FUNCTION DECLARATIONS ***/ /***********************************/ extern char *crypt (const char *, const char *); /* Prototypes for procedures local to this file. */ static void network_phase (int); static void check_idle (void *); static void connect_time_expired (void *); #if 0 static int login (char *, char *, char **, int *); #endif static void logout (void); static int null_login (int); static int get_pap_passwd (int, char *, char *); static int have_pap_secret (void); static int have_chap_secret (char *, char *, u32_t); static int ip_addr_check (u32_t, struct wordlist *); #if PAP_SUPPORT > 0 || CHAP_SUPPORT > 0 static void set_allowed_addrs(int unit, struct wordlist *addrs); static void free_wordlist (struct wordlist *); #endif #if CBCP_SUPPORT > 0 static void callback_phase (int); #endif /******************************/ /*** PUBLIC DATA STRUCTURES ***/ /******************************/ /*****************************/ /*** LOCAL DATA STRUCTURES ***/ /*****************************/ #if PAP_SUPPORT > 0 || CHAP_SUPPORT > 0 /* The name by which the peer authenticated itself to us. */ static char peer_authname[MAXNAMELEN]; #endif /* Records which authentication operations haven't completed yet. */ static int auth_pending[NUM_PPP]; /* Set if we have successfully called login() */ static int logged_in; /* Set if we have run the /etc/ppp/auth-up script. */ static int did_authup; /* List of addresses which the peer may use. */ static struct wordlist *addresses[NUM_PPP]; /* Number of network protocols which we have opened. */ static int num_np_open; /* Number of network protocols which have come up. */ static int num_np_up; #if PAP_SUPPORT > 0 || CHAP_SUPPORT > 0 /* Set if we got the contents of passwd[] from the pap-secrets file. */ static int passwd_from_file; #endif /***********************************/ /*** PUBLIC FUNCTION DEFINITIONS ***/ /***********************************/ /* * An Open on LCP has requested a change from Dead to Establish phase. * Do what's necessary to bring the physical layer up. */ void link_required(int unit) { AUTHDEBUG((LOG_INFO, "link_required: %d\n", unit)); } /* * LCP has terminated the link; go to the Dead phase and take the * physical layer down. */ void link_terminated(int unit) { AUTHDEBUG((LOG_INFO, "link_terminated: %d\n", unit)); if (lcp_phase[unit] == PHASE_DEAD) return; if (logged_in) logout(); lcp_phase[unit] = PHASE_DEAD; ppp_trace(LOG_NOTICE, "Connection terminated.\n"); pppMainWakeup(unit); } /* * LCP has gone down; it will either die or try to re-establish. */ void link_down(int unit) { int i; struct protent *protp; AUTHDEBUG((LOG_INFO, "link_down: %d\n", unit)); if (did_authup) { /* XXX Do link down processing. */ did_authup = 0; } for (i = 0; (protp = ppp_protocols[i]) != NULL; ++i) { if (!protp->enabled_flag) continue; if (protp->protocol != PPP_LCP && protp->lowerdown != NULL) (*protp->lowerdown)(unit); if (protp->protocol < 0xC000 && protp->close != NULL) (*protp->close)(unit, "LCP down"); } num_np_open = 0; num_np_up = 0; if (lcp_phase[unit] != PHASE_DEAD) lcp_phase[unit] = PHASE_TERMINATE; pppMainWakeup(unit); } /* * The link is established. * Proceed to the Dead, Authenticate or Network phase as appropriate. */ void link_established(int unit) { int auth; int i; struct protent *protp; lcp_options *wo = &lcp_wantoptions[unit]; lcp_options *go = &lcp_gotoptions[unit]; #if PAP_SUPPORT > 0 || CHAP_SUPPORT > 0 lcp_options *ho = &lcp_hisoptions[unit]; #endif AUTHDEBUG((LOG_INFO, "link_established: %d\n", unit)); /* * Tell higher-level protocols that LCP is up. */ for (i = 0; (protp = ppp_protocols[i]) != NULL; ++i) if (protp->protocol != PPP_LCP && protp->enabled_flag && protp->lowerup != NULL) (*protp->lowerup)(unit); if (ppp_settings.auth_required && !(go->neg_chap || go->neg_upap)) { /* * We wanted the peer to authenticate itself, and it refused: * treat it as though it authenticated with PAP using a username * of "" and a password of "". If that's not OK, boot it out. */ if (!wo->neg_upap || !null_login(unit)) { ppp_trace(LOG_WARNING, "peer refused to authenticate\n"); lcp_close(unit, "peer refused to authenticate"); return; } } lcp_phase[unit] = PHASE_AUTHENTICATE; auth = 0; #if CHAP_SUPPORT > 0 if (go->neg_chap) { ChapAuthPeer(unit, ppp_settings.our_name, go->chap_mdtype); auth |= CHAP_PEER; } #endif #if PAP_SUPPORT > 0 && CHAP_SUPPORT > 0 else #endif #if PAP_SUPPORT > 0 if (go->neg_upap) { upap_authpeer(unit); auth |= PAP_PEER; } #endif #if CHAP_SUPPORT > 0 if (ho->neg_chap) { ChapAuthWithPeer(unit, ppp_settings.user, ho->chap_mdtype); auth |= CHAP_WITHPEER; } #endif #if PAP_SUPPORT > 0 && CHAP_SUPPORT > 0 else #endif #if PAP_SUPPORT > 0 if (ho->neg_upap) { if (ppp_settings.passwd[0] == 0) { passwd_from_file = 1; if (!get_pap_passwd(unit, ppp_settings.user, ppp_settings.passwd)) ppp_trace(LOG_ERR, "No secret found for PAP login\n"); } upap_authwithpeer(unit, ppp_settings.user, ppp_settings.passwd); auth |= PAP_WITHPEER; } #endif auth_pending[unit] = auth; if (!auth) network_phase(unit); } /* * The peer has failed to authenticate himself using `protocol'. */ void auth_peer_fail(int unit, u16_t protocol) { AUTHDEBUG((LOG_INFO, "auth_peer_fail: %d proto=%X\n", unit, protocol)); /* * Authentication failure: take the link down */ lcp_close(unit, "Authentication failed"); } #if PAP_SUPPORT > 0 || CHAP_SUPPORT > 0 /* * The peer has been successfully authenticated using `protocol'. */ void auth_peer_success(int unit, u16_t protocol, char *name, int namelen) { int pbit; AUTHDEBUG((LOG_INFO, "auth_peer_success: %d proto=%X\n", unit, protocol)); switch (protocol) { case PPP_CHAP: pbit = CHAP_PEER; break; case PPP_PAP: pbit = PAP_PEER; break; default: ppp_trace(LOG_WARNING, "auth_peer_success: unknown protocol %x\n", protocol); return; } /* * Save the authenticated name of the peer for later. */ if (namelen > sizeof(peer_authname) - 1) namelen = sizeof(peer_authname) - 1; BCOPY(name, peer_authname, namelen); peer_authname[namelen] = 0; /* * If there is no more authentication still to be done, * proceed to the network (or callback) phase. */ if ((auth_pending[unit] &= ~pbit) == 0) network_phase(unit); } /* * We have failed to authenticate ourselves to the peer using `protocol'. */ void auth_withpeer_fail(int unit, u16_t protocol) { int errCode = PPPERR_AUTHFAIL; AUTHDEBUG((LOG_INFO, "auth_withpeer_fail: %d proto=%X\n", unit, protocol)); if (passwd_from_file) BZERO(ppp_settings.passwd, MAXSECRETLEN); /* * XXX Warning: the unit number indicates the interface which is * not necessarily the PPP connection. It works here as long * as we are only supporting PPP interfaces. */ pppIOCtl(unit, PPPCTLS_ERRCODE, &errCode); /* * We've failed to authenticate ourselves to our peer. * He'll probably take the link down, and there's not much * we can do except wait for that. */ } /* * We have successfully authenticated ourselves with the peer using `protocol'. */ void auth_withpeer_success(int unit, u16_t protocol) { int pbit; AUTHDEBUG((LOG_INFO, "auth_withpeer_success: %d proto=%X\n", unit, protocol)); switch (protocol) { case PPP_CHAP: pbit = CHAP_WITHPEER; break; case PPP_PAP: if (passwd_from_file) BZERO(ppp_settings.passwd, MAXSECRETLEN); pbit = PAP_WITHPEER; break; default: ppp_trace(LOG_WARNING, "auth_peer_success: unknown protocol %x\n", protocol); pbit = 0; } /* * If there is no more authentication still being done, * proceed to the network (or callback) phase. */ if ((auth_pending[unit] &= ~pbit) == 0) network_phase(unit); } #endif /* * np_up - a network protocol has come up. */ void np_up(int unit, u16_t proto) { AUTHDEBUG((LOG_INFO, "np_up: %d proto=%X\n", unit, proto)); if (num_np_up == 0) { AUTHDEBUG((LOG_INFO, "np_up: maxconnect=%d idle_time_limit=%d\n",ppp_settings.maxconnect,ppp_settings.idle_time_limit)); /* * At this point we consider that the link has come up successfully. */ if (ppp_settings.idle_time_limit > 0) TIMEOUT(check_idle, NULL, ppp_settings.idle_time_limit); /* * Set a timeout to close the connection once the maximum * connect time has expired. */ if (ppp_settings.maxconnect > 0) TIMEOUT(connect_time_expired, 0, ppp_settings.maxconnect); } ++num_np_up; } /* * np_down - a network protocol has gone down. */ void np_down(int unit, u16_t proto) { AUTHDEBUG((LOG_INFO, "np_down: %d proto=%X\n", unit, proto)); if (--num_np_up == 0 && ppp_settings.idle_time_limit > 0) { UNTIMEOUT(check_idle, NULL); } } /* * np_finished - a network protocol has finished using the link. */ void np_finished(int unit, u16_t proto) { AUTHDEBUG((LOG_INFO, "np_finished: %d proto=%X\n", unit, proto)); if (--num_np_open <= 0) { /* no further use for the link: shut up shop. */ lcp_close(0, "No network protocols running"); } } /* * auth_reset - called when LCP is starting negotiations to recheck * authentication options, i.e. whether we have appropriate secrets * to use for authenticating ourselves and/or the peer. */ void auth_reset(int unit) { lcp_options *go = &lcp_gotoptions[unit]; lcp_options *ao = &lcp_allowoptions[0]; ipcp_options *ipwo = &ipcp_wantoptions[0]; u32_t remote; AUTHDEBUG((LOG_INFO, "auth_reset: %d\n", unit)); ao->neg_upap = !ppp_settings.refuse_pap && (ppp_settings.passwd[0] != 0 || get_pap_passwd(unit, NULL, NULL)); ao->neg_chap = !ppp_settings.refuse_chap && have_chap_secret(ppp_settings.user, ppp_settings.remote_name, (u32_t)0); if (go->neg_upap && !have_pap_secret()) go->neg_upap = 0; if (go->neg_chap) { remote = ipwo->accept_remote? 0: ipwo->hisaddr; if (!have_chap_secret(ppp_settings.remote_name, ppp_settings.our_name, remote)) go->neg_chap = 0; } } #if PAP_SUPPORT > 0 /* * check_passwd - Check the user name and passwd against the PAP secrets * file. If requested, also check against the system password database, * and login the user if OK. * * returns: * UPAP_AUTHNAK: Authentication failed. * UPAP_AUTHACK: Authentication succeeded. * In either case, msg points to an appropriate message. */ int check_passwd( int unit, char *auser, int userlen, char *apasswd, int passwdlen, char **msg, int *msglen ) { #if 1 *msg = (char *) 0; return UPAP_AUTHACK; /* XXX Assume all entries OK. */ #else int ret = 0; struct wordlist *addrs = NULL; char passwd[256], user[256]; char secret[MAXWORDLEN]; static u_short attempts = 0; /* * Make copies of apasswd and auser, then null-terminate them. */ BCOPY(apasswd, passwd, passwdlen); passwd[passwdlen] = '\0'; BCOPY(auser, user, userlen); user[userlen] = '\0'; *msg = (char *) 0; /* XXX Validate user name and password. */ ret = UPAP_AUTHACK; /* XXX Assume all entries OK. */ if (ret == UPAP_AUTHNAK) { if (*msg == (char *) 0) *msg = "Login incorrect"; *msglen = strlen(*msg); /* * Frustrate passwd stealer programs. * Allow 10 tries, but start backing off after 3 (stolen from login). * On 10'th, drop the connection. */ if (attempts++ >= 10) { ppp_trace(LOG_WARNING, "%d LOGIN FAILURES BY %s\n", attempts, user); ppp_panic("Excess Bad Logins"); } if (attempts > 3) { ppp_msleep((attempts - 3) * 5); } if (addrs != NULL) { free_wordlist(addrs); } } else { attempts = 0; /* Reset count */ if (*msg == (char *) 0) *msg = "Login ok"; *msglen = strlen(*msg); set_allowed_addrs(unit, addrs); } BZERO(passwd, sizeof(passwd)); BZERO(secret, sizeof(secret)); return ret; #endif } #endif /* * auth_ip_addr - check whether the peer is authorized to use * a given IP address. Returns 1 if authorized, 0 otherwise. */ int auth_ip_addr(int unit, u32_t addr) { return ip_addr_check(addr, addresses[unit]); } /* * bad_ip_adrs - return 1 if the IP address is one we don't want * to use, such as an address in the loopback net or a multicast address. * addr is in network byte order. */ int bad_ip_adrs(u32_t addr) { addr = ntohl(addr); return (addr >> IN_CLASSA_NSHIFT) == IN_LOOPBACKNET || IN_MULTICAST(addr) || IN_BADCLASS(addr); } #if CHAP_SUPPORT > 0 /* * get_secret - open the CHAP secret file and return the secret * for authenticating the given client on the given server. * (We could be either client or server). */ int get_secret( int unit, char *client, char *server, char *secret, int *secret_len, int save_addrs ) { #if 1 return 0; #else int ret = 0, len; struct wordlist *addrs; char secbuf[MAXWORDLEN]; addrs = NULL; secbuf[0] = 0; /* XXX Find secret. */ if (ret < 0) return 0; if (save_addrs) set_allowed_addrs(unit, addrs); len = strlen(secbuf); if (len > MAXSECRETLEN) { ppp_trace(LOG_ERR, "Secret for %s on %s is too long\n", client, server); len = MAXSECRETLEN; } BCOPY(secbuf, secret, len); BZERO(secbuf, sizeof(secbuf)); *secret_len = len; return 1; #endif } #endif #if 0 /* UNUSED */ /* * auth_check_options - called to check authentication options. */ void auth_check_options(void) { lcp_options *wo = &lcp_wantoptions[0]; int can_auth; ipcp_options *ipwo = &ipcp_wantoptions[0]; u32_t remote; /* Default our_name to hostname, and user to our_name */ if (ppp_settings.our_name[0] == 0 || ppp_settings.usehostname) strcpy(ppp_settings.our_name, ppp_settings.hostname); if (ppp_settings.user[0] == 0) strcpy(ppp_settings.user, ppp_settings.our_name); /* If authentication is required, ask peer for CHAP or PAP. */ if (ppp_settings.auth_required && !wo->neg_chap && !wo->neg_upap) { wo->neg_chap = 1; wo->neg_upap = 1; } /* * Check whether we have appropriate secrets to use * to authenticate the peer. */ can_auth = wo->neg_upap && have_pap_secret(); if (!can_auth && wo->neg_chap) { remote = ipwo->accept_remote? 0: ipwo->hisaddr; can_auth = have_chap_secret(ppp_settings.remote_name, ppp_settings.our_name, remote); } if (ppp_settings.auth_required && !can_auth) { ppp_panic("No auth secret"); } } #endif /**********************************/ /*** LOCAL FUNCTION DEFINITIONS ***/ /**********************************/ /* * Proceed to the network phase. */ static void network_phase(int unit) { int i; struct protent *protp; lcp_options *go = &lcp_gotoptions[unit]; /* * If the peer had to authenticate, run the auth-up script now. */ if ((go->neg_chap || go->neg_upap) && !did_authup) { /* XXX Do setup for peer authentication. */ did_authup = 1; } #if CBCP_SUPPORT > 0 /* * If we negotiated callback, do it now. */ if (go->neg_cbcp) { lcp_phase[unit] = PHASE_CALLBACK; (*cbcp_protent.open)(unit); return; } #endif lcp_phase[unit] = PHASE_NETWORK; for (i = 0; (protp = ppp_protocols[i]) != NULL; ++i) if (protp->protocol < 0xC000 && protp->enabled_flag && protp->open != NULL) { (*protp->open)(unit); if (protp->protocol != PPP_CCP) ++num_np_open; } if (num_np_open == 0) /* nothing to do */ lcp_close(0, "No network protocols running"); } /* * check_idle - check whether the link has been idle for long * enough that we can shut it down. */ static void check_idle(void *arg) { struct ppp_idle idle; u_short itime; (void)arg; if (!get_idle_time(0, &idle)) return; itime = LWIP_MIN(idle.xmit_idle, idle.recv_idle); if (itime >= ppp_settings.idle_time_limit) { /* link is idle: shut it down. */ ppp_trace(LOG_INFO, "Terminating connection due to lack of activity.\n"); lcp_close(0, "Link inactive"); } else { TIMEOUT(check_idle, NULL, ppp_settings.idle_time_limit - itime); } } /* * connect_time_expired - log a message and close the connection. */ static void connect_time_expired(void *arg) { (void)arg; ppp_trace(LOG_INFO, "Connect time expired\n"); lcp_close(0, "Connect time expired"); /* Close connection */ } #if 0 /* * login - Check the user name and password against the system * password database, and login the user if OK. * * returns: * UPAP_AUTHNAK: Login failed. * UPAP_AUTHACK: Login succeeded. * In either case, msg points to an appropriate message. */ static int login(char *user, char *passwd, char **msg, int *msglen) { /* XXX Fail until we decide that we want to support logins. */ return (UPAP_AUTHNAK); } #endif /* * logout - Logout the user. */ static void logout(void) { logged_in = 0; } /* * null_login - Check if a username of "" and a password of "" are * acceptable, and iff so, set the list of acceptable IP addresses * and return 1. */ static int null_login(int unit) { (void)unit; /* XXX Fail until we decide that we want to support logins. */ return 0; } /* * get_pap_passwd - get a password for authenticating ourselves with * our peer using PAP. Returns 1 on success, 0 if no suitable password * could be found. */ static int get_pap_passwd(int unit, char *user, char *passwd) { /* normally we would reject PAP if no password is provided, but this causes problems with some providers (like CHT in Taiwan) who incorrectly request PAP and expect a bogus/empty password, so always provide a default user/passwd of "none"/"none" */ if(user) strcpy(user, "none"); if(passwd) strcpy(passwd, "none"); return 1; } /* * have_pap_secret - check whether we have a PAP file with any * secrets that we could possibly use for authenticating the peer. */ static int have_pap_secret(void) { /* XXX Fail until we set up our passwords. */ return 0; } /* * have_chap_secret - check whether we have a CHAP file with a * secret that we could possibly use for authenticating `client' * on `server'. Either can be the null string, meaning we don't * know the identity yet. */ static int have_chap_secret(char *client, char *server, u32_t remote) { (void)client; (void)server; (void)remote; /* XXX Fail until we set up our passwords. */ return 0; } #if PAP_SUPPORT > 0 || CHAP_SUPPORT > 0 /* * set_allowed_addrs() - set the list of allowed addresses. */ static void set_allowed_addrs(int unit, struct wordlist *addrs) { if (addresses[unit] != NULL) free_wordlist(addresses[unit]); addresses[unit] = addrs; #if 0 /* * If there's only one authorized address we might as well * ask our peer for that one right away */ if (addrs != NULL && addrs->next == NULL) { char *p = addrs->word; struct ipcp_options *wo = &ipcp_wantoptions[unit]; u32_t a; struct hostent *hp; if (wo->hisaddr == 0 && *p != '!' && *p != '-' && strchr(p, '/') == NULL) { hp = gethostbyname(p); if (hp != NULL && hp->h_addrtype == AF_INET) a = *(u32_t *)hp->h_addr; else a = inet_addr(p); if (a != (u32_t) -1) wo->hisaddr = a; } } #endif } #endif static int ip_addr_check(u32_t addr, struct wordlist *addrs) { /* don't allow loopback or multicast address */ if (bad_ip_adrs(addr)) return 0; if (addrs == NULL) return !ppp_settings.auth_required; /* no addresses authorized */ /* XXX All other addresses allowed. */ return 1; } #if PAP_SUPPORT > 0 || CHAP_SUPPORT /* * free_wordlist - release memory allocated for a wordlist. */ static void free_wordlist(struct wordlist *wp) { struct wordlist *next; while (wp != NULL) { next = wp->next; free(wp); wp = next; } } #endif #endif /* PPP_SUPPORT */