/* * Copyright (c) 2000 Apple Computer, Inc. All rights reserved. * * @APPLE_LICENSE_HEADER_START@ * * The contents of this file constitute Original Code as defined in and * are subject to the Apple Public Source License Version 1.1 (the * "License"). You may not use this file except in compliance with the * License. Please obtain a copy of the License at * http://www.apple.com/publicsource and read it before using this file. * * This Original Code and all software distributed under the License are * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES, * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY, * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT. Please see the * License for the specific language governing rights and limitations * under the License. * * @APPLE_LICENSE_HEADER_END@ */ /* * 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. */ /* ----------------------------------------------------------------------------- includes ----------------------------------------------------------------------------- */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include "ppp_msg.h" #include "../Family/PPP.kmodproj/ppp.h" #include "fsm.h" #include "lcp.h" #include "ipcp.h" #include "chap.h" #include "upap.h" #include "auth.h" #include "ppp_client.h" #include "ppp_utils.h" #include "ppp_command.h" #include "ppp_manager.h" #include "ppp_utils.h" #include "link.h" #include "auth.h" #ifdef CBCP_SUPPORT #include "cbcp.h" #endif #include "pathnames.h" /* ----------------------------------------------------------------------------- Definitions ----------------------------------------------------------------------------- */ /* Bits in scan_authfile return value */ #define NONWILD_SERVER 1 #define NONWILD_CLIENT 2 #define ISWILD(word) (word[0] == '*' && word[1] == 0) /* Bits in auth_pending[] */ #define PAP_WITHPEER 1 #define PAP_PEER 2 #define CHAP_WITHPEER 4 #define CHAP_PEER 8 /* ----------------------------------------------------------------------------- Forward declarations ----------------------------------------------------------------------------- */ extern char *crypt __P((const char *, const char *)); /* Prototypes for procedures local to this file. */ static void network_phase(struct ppp *ppp); static void check_idle(CFRunLoopTimerRef timer, void *); static void connect_time_expired(CFRunLoopTimerRef timer, void *); //static int get_pap_passwd(struct ppp *ppp, char *); //static int have_pap_secret(int *); //static int have_chap_secret(char *, char *, int, int *); static int ip_addr_check(u_int32_t, struct permitted_ip *); static void free_wordlist(struct wordlist *); static void set_allowed_addrs(struct ppp *ppp, struct wordlist *addrs, struct wordlist *opts); //static int some_ip_ok(struct wordlist *); //static int setupapfile(char **); //static int set_noauth_addr(char **); static int scan_authfile(struct ppp *ppp, FILE *f, char *client, char *server, char *secret, struct wordlist **addrs, struct wordlist **opts, char *filename); int getword __P((FILE *f, char *word, int *newlinep, char *filename)); /* Read a word from a file */ /* ----------------------------------------------------------------------------- * An Open on LCP has requested a change from Dead to Establish phase. * Do what's necessary to bring the physical layer up. ----------------------------------------------------------------------------- */ void auth_link_required(struct ppp *ppp) { } /* ----------------------------------------------------------------------------- * LCP has terminated the link; go to the Dead phase and take the * physical layer down. ----------------------------------------------------------------------------- */ void auth_link_terminated(struct ppp *ppp) { if (ppp->phase == PPP_IDLE) return; ppp_new_phase(ppp, PPP_TERMINATE); link_disconnect(ppp); } /* ----------------------------------------------------------------------------- * LCP has gone down; it will either die or try to re-establish. ----------------------------------------------------------------------------- */ void auth_link_down(struct ppp *ppp) { int i; struct protent *protp; for (i = 0; (protp = ppp->protocols[i]) != NULL; ++i) { if (protp->protocol != PPP_LCP && protp->lowerdown != NULL) (*protp->lowerdown)(ppp); if (protp->protocol < 0xC000 && protp->close != NULL) (*protp->close)(ppp, "LCP down"); } ppp->num_np_open = 0; ppp->num_np_up = 0; if (ppp->phase != PPP_IDLE) { ppp_new_phase(ppp, PPP_TERMINATE); // don't disconnect, as it could be a lcp renegociation (l2tp) //link_disconnect(ppp); } } /* ----------------------------------------------------------------------------- * The link is established. * Proceed to the Dead, Authenticate or Network phase as appropriate. ----------------------------------------------------------------------------- */ void auth_link_established(struct ppp *ppp) { int auth; // lcp_options *wo = &ppp->lcp_wantoptions; lcp_options *go = &ppp->lcp_gotoptions; lcp_options *ho = &ppp->lcp_hisoptions; int i; struct protent *protp; /* * Tell higher-level protocols that LCP is up. */ for (i = 0; (protp = ppp->protocols[i]) != NULL; ++i) if (protp->protocol != PPP_LCP && protp->lowerup != NULL) (*protp->lowerup)(ppp); if (ppp->auth_required && !(go->neg_chap || go->neg_upap)) { /* * We wanted the peer to authenticate itself, and it refused: * if we have some address(es) it can use without auth, fine, * otherwise treat it as though it authenticated with PAP using * a username * of "" and a password of "". If that's not OK, * boot it out. */ warn(ppp, "peer refused to authenticate: terminating link"); lcp_close(ppp, "peer refused to authenticate"); ppp->status = PPP_ERR_AUTHFAILED; return; #if 0 if (ppp->noauth_addrs != NULL) { set_allowed_addrs(ppp, ppp->noauth_addrs, NULL); } else if (!wo->neg_upap || !null_login(ppp)) { warn(ppp, "peer refused to authenticate: terminating link"); lcp_close(ppp, "peer refused to authenticate"); ppp->status = EXIT_PEER_AUTH_FAILED; return; } #endif } ppp_new_phase(ppp, PPP_AUTHENTICATE); auth = 0; if (go->neg_chap) { ChapAuthPeer(ppp, ppp->our_name, go->chap_mdtype); auth |= CHAP_PEER; } else if (go->neg_upap) { upap_authpeer(ppp); auth |= PAP_PEER; } if (ho->neg_chap) { ChapAuthWithPeer(ppp, ppp->user, ho->chap_mdtype); auth |= CHAP_WITHPEER; } else if (ho->neg_upap) { #if 0 if (passwd[0] == 0) { passwd_from_file = 1; if (!get_pap_passwd(ppp, ppp->passwd)) error(ppp, "No secret found for PAP login"); } #endif upap_authwithpeer(ppp, ppp->user, ppp->passwd); auth |= PAP_WITHPEER; } ppp->auth_pending = auth; if (auth) ppp_new_event(ppp, PPP_EVT_AUTH_STARTED); if (!auth) network_phase(ppp); } /* ----------------------------------------------------------------------------- * Proceed to the network phase. ----------------------------------------------------------------------------- */ static void network_phase(struct ppp *ppp) { // lcp_options *go = &ppp->lcp_gotoptions; #ifdef CBCP_SUPPORT /* * If we negotiated callback, do it now. */ if (go->neg_cbcp) { ppp_new_phase(ppp, PPP_CALLBACK); (*cbcp_protent.open)(ppp); return; } #endif auth_start_networks(ppp); } /* ----------------------------------------------------------------------------- ----------------------------------------------------------------------------- */ void auth_start_networks(struct ppp *ppp) { int i; struct protent *protp; ppp_new_phase(ppp, PPP_NETWORK); for (i = 0; (protp = ppp->protocols[i]) != NULL; ++i) { if (protp->protocol < 0xC000 && protp->open != NULL) { (*protp->open)(ppp); if (protp->protocol != PPP_CCP) ++ppp->num_np_open; } } if (ppp->num_np_open == 0) /* nothing to do */ lcp_close(ppp, "No network protocols running"); } /* ----------------------------------------------------------------------------- * The peer has failed to authenticate himself using `protocol'. ----------------------------------------------------------------------------- */ void auth_peer_fail(struct ppp *ppp, int protocol) { /* * Authentication failure: take the link down */ lcp_close(ppp, "Authentication failed"); // ppp->status = EXIT_PEER_AUTH_FAILED; ppp->status = PPP_ERR_AUTHFAILED; // ??? maybe need a more specific server authe fail error } /* ----------------------------------------------------------------------------- * The peer has been successfully authenticated using `protocol'. ----------------------------------------------------------------------------- */ void auth_peer_success(struct ppp *ppp, int protocol, char *name, int namelen) { int bit; switch (protocol) { case PPP_CHAP: bit = CHAP_PEER; break; case PPP_PAP: bit = PAP_PEER; break; default: warn(ppp, "auth_peer_success: unknown protocol %x", protocol); return; } /* * Save the authenticated name of the peer for later. */ if (namelen > sizeof(ppp->peer_authname) - 1) namelen = sizeof(ppp->peer_authname) - 1; BCOPY(name, ppp->peer_authname, namelen); ppp->peer_authname[namelen] = 0; /* * If there is no more authentication still to be done, * proceed to the network (or callback) phase. */ if ((ppp->auth_pending &= ~bit) == 0) network_phase(ppp); } /* ----------------------------------------------------------------------------- * We have failed to authenticate ourselves to the peer using `protocol'. ----------------------------------------------------------------------------- */ void auth_withpeer_fail(struct ppp *ppp, int protocol) { ppp_new_event(ppp, PPP_EVT_AUTH_FAILED); if (ppp->passwd_from_file) BZERO(ppp->passwd, MAXSECRETLEN); /* * We've failed to authenticate ourselves to our peer. * Some servers keep sending CHAP challenges, but there * is no point in persisting without any way to get updated * authentication secrets. */ lcp_close(ppp, "Failed to authenticate ourselves to peer"); //ppp->status = EXIT_AUTH_TOPEER_FAILED; ppp->status = PPP_ERR_AUTHFAILED; } /* ----------------------------------------------------------------------------- * We have successfully authenticated ourselves with the peer using `protocol'. ----------------------------------------------------------------------------- */ void auth_withpeer_success(struct ppp *ppp, int protocol) { int bit; ppp_new_event(ppp, PPP_EVT_AUTH_SUCCEDED); switch (protocol) { case PPP_CHAP: bit = CHAP_WITHPEER; break; case PPP_PAP: if (ppp->passwd_from_file) BZERO(ppp->passwd, MAXSECRETLEN); bit = PAP_WITHPEER; break; default: warn(ppp, "auth_withpeer_success: unknown protocol %x", protocol); bit = 0; } /* * If there is no more authentication still being done, * proceed to the network (or callback) phase. */ if ((ppp->auth_pending &= ~bit) == 0) network_phase(ppp); } /* ----------------------------------------------------------------------------- * np_up - a network protocol has come up. ----------------------------------------------------------------------------- */ void auth_np_up(struct ppp *ppp, int proto) { int tlim; struct timeval tval; struct timezone tzone; if (ppp->num_np_up == 0) { /* * At this point we consider that the link has come up successfully. */ //ppp->status = EXIT_OK; ppp->unsuccess = 0; if (!gettimeofday(&tval, &tzone)) { ppp->conntime = tval.tv_sec; } ppp_new_phase(ppp, PPP_RUNNING); tlim = ppp->link_idle_timer; if (tlim > 0) ppp->auth_idleTORef = AddTimerToRunLoop(check_idle, ppp, tlim); /* * Set a timeout to close the connection once the maximum * connect time has expired. */ if (ppp->link_session_timer > 0) ppp->auth_sessionTORef = AddTimerToRunLoop(connect_time_expired, ppp, ppp->link_session_timer); } ++ppp->num_np_up; } /* ----------------------------------------------------------------------------- * np_down - a network protocol has gone down. ----------------------------------------------------------------------------- */ void auth_np_down(struct ppp *ppp, int proto) { if (--ppp->num_np_up == 0) { DelTimerFromRunLoop(&(ppp->auth_idleTORef)); /* Cancel timeout */ DelTimerFromRunLoop(&(ppp->auth_sessionTORef)); /* Cancel timeout */ ppp_new_phase(ppp, PPP_NETWORK); } } /* ----------------------------------------------------------------------------- * np_finished - a network protocol has finished using the link. ----------------------------------------------------------------------------- */ void auth_np_finished(struct ppp *ppp, int proto) { if (--ppp->num_np_open <= 0) { /* no further use for the link: shut up shop. */ lcp_close(ppp, "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(CFRunLoopTimerRef timer, void *arg) { struct ppp *ppp = (struct ppp *)arg; struct ppp_idle idle; time_t itime; int tlim; if (ppp_get_idle_time(ppp, &idle)) return; itime = MIN(idle.xmit_idle, idle.recv_idle); tlim = ppp->link_idle_timer - itime; if (tlim <= 0) { /* link is idle: shut it down. */ notice(ppp, "Terminating connection due to lack of activity."); lcp_close(ppp, "Link inactive"); //ppp->need_holdoff = 0; //ppp->status = EXIT_IDLE_TIMEOUT; ppp->status = PPP_ERR_IDLETIMEOUT; } else { ppp->auth_idleTORef = AddTimerToRunLoop(check_idle, ppp, tlim); } } /* ----------------------------------------------------------------------------- * connect_time_expired - log a message and close the connection. ----------------------------------------------------------------------------- */ static void connect_time_expired(CFRunLoopTimerRef timer, void *arg) { struct ppp *ppp = (struct ppp *)arg; //info("Connect time expired"); // could generate an event ? lcp_close(ppp, "Connect time expired"); /* Close connection */ ppp->status = PPP_ERR_SESSIONTIMEOUT; //ppp->status = EXIT_CONNECT_TIME; } /* ----------------------------------------------------------------------------- * 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(struct ppp *ppp) { lcp_options *ao = &ppp->lcp_allowoptions; ao->neg_upap = 1; ao->neg_chap = 1; } /* ----------------------------------------------------------------------------- * 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(struct ppp *ppp, char *auser, int userlen, char *apasswd, int passwdlen, char **msg) { int ret = 0; char *filename; FILE *f; struct wordlist *addrs = NULL, *opts = NULL; char passwd[256], user[256]; char secret[MAXWORDLEN]; /* * Make copies of apasswd and auser, then null-terminate them. * If there are unprintable characters in the password, make them visible. */ slprintf(ppp, passwd, sizeof(passwd), "%.*v", passwdlen, apasswd); slprintf(ppp, user, sizeof(user), "%.*v", userlen, auser); *msg = ""; /* * Open the file of pap secrets and scan for a suitable secret * for authenticating this user. */ filename = PATH_SECRETS; addrs = opts = NULL; ret = UPAP_AUTHNAK; f = fopen(filename, "r"); if (f == NULL) { error(ppp, "Can't open PAP password file %s: %m", filename); } else { if (scan_authfile(ppp, f, user, ppp->our_name, secret, &addrs, &opts, filename) < 0) { warn(ppp, "no PAP secret found for %s", user); } else if (secret[0] != 0) { /* password given in pap-secrets - must match */ if (strcmp(passwd, secret) == 0) ret = UPAP_AUTHACK; else warn(ppp, "PAP authentication failure for %s", user); } else { /* empty password in pap-secrets and login option not used */ ret = UPAP_AUTHACK; } fclose(f); } if (ret == UPAP_AUTHNAK) { if (**msg == 0) *msg = "Login incorrect"; /* * XXX can we ever get here more than once?? * Frustrate passwd stealer programs. * Allow 10 tries, but start backing off after 3 (stolen from login). * On 10'th, drop the connection. */ if (ppp->upap_attempts++ >= 10) { warn(ppp, "%d LOGIN FAILURES ON %s, %s", ppp->upap_attempts, ppp->devnam, user); lcp_close(ppp, "login failed"); } //if (ppp->upap_attempts > 3) // sleep((u_int) (ppp->upap_attempts - 3) * 5); if (opts != NULL) free_wordlist(opts); } else { ppp->upap_attempts = 0; /* Reset count */ if (**msg == 0) *msg = "Login ok"; set_allowed_addrs(ppp, addrs, opts); } if (addrs != NULL) free_wordlist(addrs); BZERO(passwd, sizeof(passwd)); BZERO(secret, sizeof(secret)); return ret; } #if 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(struct ppp *ppp) { char *filename; FILE *f; int i, ret; struct wordlist *addrs, *opts; char secret[MAXWORDLEN]; /* * Open the file of pap secrets and scan for a suitable secret. */ filename = _PATH_UPAPFILE; addrs = NULL; f = fopen(filename, "r"); if (f == NULL) return 0; i = scan_authfile(ppp, f, "", our_name, secret, &addrs, &opts, filename); ret = i >= 0 && secret[0] == 0; BZERO(secret, sizeof(secret)); if (ret) set_allowed_addrs(ppp, addrs, opts); else if (opts != 0) free_wordlist(opts); if (addrs != 0) free_wordlist(addrs); fclose(f); return ret; } #endif /* ----------------------------------------------------------------------------- * set_allowed_addrs() - set the list of allowed addresses. * Also looks for `--' indicating options to apply for this peer * and leaves the following words in extra_options. ----------------------------------------------------------------------------- */ static void set_allowed_addrs(struct ppp *ppp, struct wordlist *addrs, struct wordlist *opts) { int n; struct wordlist *ap, **pap; struct permitted_ip *ip; char *ptr_word, *ptr_mask; struct hostent *hp; struct netent *np; u_int32_t a, mask, ah, offset; struct ipcp_options *wo = &ppp->ipcp_wantoptions; u_int32_t suggested_ip = 0; if (ppp->addresses != NULL) free(ppp->addresses); ppp->addresses = NULL; if (ppp->extra_options != NULL) free_wordlist(ppp->extra_options); ppp->extra_options = opts; /* * Count the number of IP addresses given. */ for (n = 0, pap = &addrs; (ap = *pap) != NULL; pap = &ap->next) ++n; if (n == 0) return; ip = (struct permitted_ip *) malloc((n + 1) * sizeof(struct permitted_ip)); if (ip == 0) return; n = 0; for (ap = addrs; ap != NULL; ap = ap->next) { /* "-" means no addresses authorized, "*" means any address allowed */ ptr_word = ap->word; if (strcmp(ptr_word, "-") == 0) break; if (strcmp(ptr_word, "*") == 0) { ip[n].permit = 1; ip[n].base = ip[n].mask = 0; ++n; break; } ip[n].permit = 1; if (*ptr_word == '!') { ip[n].permit = 0; ++ptr_word; } mask = ~ (u_int32_t) 0; offset = 0; ptr_mask = strchr (ptr_word, '/'); if (ptr_mask != NULL) { int bit_count; char *endp; bit_count = (int) strtol (ptr_mask+1, &endp, 10); if (bit_count <= 0 || bit_count > 32) { warn(ppp, "invalid address length %v in auth. address list", ptr_mask+1); continue; } bit_count = 32 - bit_count; /* # bits in host part */ if (*endp == '+') { offset = ppp->unit + 1; ++endp; } if (*endp != 0) { warn(ppp, "invalid address length syntax: %v", ptr_mask+1); continue; } *ptr_mask = '\0'; mask <<= bit_count; } hp = gethostbyname(ptr_word); if (hp != NULL && hp->h_addrtype == AF_INET) { a = *(u_int32_t *)hp->h_addr; } else { np = getnetbyname (ptr_word); if (np != NULL && np->n_addrtype == AF_INET) { a = htonl (*(u_int32_t *)np->n_net); if (ptr_mask == NULL) { /* calculate appropriate mask for net */ ah = ntohl(a); if (IN_CLASSA(ah)) mask = IN_CLASSA_NET; else if (IN_CLASSB(ah)) mask = IN_CLASSB_NET; else if (IN_CLASSC(ah)) mask = IN_CLASSC_NET; } } else { a = inet_addr (ptr_word); } } if (ptr_mask != NULL) *ptr_mask = '/'; if (a == (u_int32_t)-1L) { warn(ppp, "unknown host %s in auth. address list", ap->word); continue; } if (offset != 0) { if (offset >= ~mask) { warn(ppp, "interface unit %d too large for subnet %v", ppp->unit, ptr_word); continue; } a = htonl((ntohl(a) & mask) + offset); mask = ~(u_int32_t)0; } ip[n].mask = htonl(mask); ip[n].base = a & ip[n].mask; ++n; if (~mask == 0 && suggested_ip == 0) suggested_ip = a; } ip[n].permit = 0; /* make the last entry forbid all addresses */ ip[n].base = 0; /* to terminate the list */ ip[n].mask = 0; ppp->addresses = ip; /* * If the address given for the peer isn't authorized, or if * the user hasn't given one, AND there is an authorized address * which is a single host, then use that if we find one. */ if (suggested_ip != 0 && (wo->hisaddr == 0 || !auth_ip_addr(ppp, wo->hisaddr))) wo->hisaddr = suggested_ip; } /* ----------------------------------------------------------------------------- * 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(struct ppp *ppp, u_int32_t addr) { int ok; /* don't allow loopback or multicast address */ if (bad_ip_adrs(addr)) return 0; if (ppp->addresses != NULL) { ok = ip_addr_check(addr, ppp->addresses); if (ok >= 0) return ok; } if (ppp->auth_required) return 0; /* no addresses authorized */ return ppp->allow_any_ip || !have_route_to(addr); } /* ----------------------------------------------------------------------------- ----------------------------------------------------------------------------- */ static int ip_addr_check(u_int32_t addr, struct permitted_ip * addrs) { for (; ; ++addrs) if ((addr & addrs->mask) == addrs->base) return addrs->permit; } /* ----------------------------------------------------------------------------- * 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(struct ppp *ppp, char *client, char *server, char *secret, int *secret_len, int am_server) { FILE *f; int ret, len; char *filename; struct wordlist *addrs, *opts; char secbuf[MAXWORDLEN]; if (!am_server && ppp->passwd[0] != 0) { strlcpy(secbuf, ppp->passwd, sizeof(secbuf)); } else { filename = PATH_SECRETS; addrs = NULL; secbuf[0] = 0; f = fopen(filename, "r"); if (f == NULL) { error(ppp, "Can't open chap secret file %s: %m", filename); return 0; } ret = scan_authfile(ppp, f, client, server, secbuf, &addrs, &opts, filename); fclose(f); if (ret < 0) return 0; if (am_server) set_allowed_addrs(ppp, addrs, opts); else if (opts != 0) free_wordlist(opts); if (addrs != 0) free_wordlist(addrs); } len = strlen(secbuf); if (len > MAXSECRETLEN) { error(ppp, "Secret for %s on %s is too long", client, server); len = MAXSECRETLEN; } BCOPY(secbuf, secret, len); BZERO(secbuf, sizeof(secbuf)); *secret_len = len; return 1; } /* ----------------------------------------------------------------------------- * 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(u_int32_t addr) { addr = ntohl(addr); return (addr >> IN_CLASSA_NSHIFT) == IN_LOOPBACKNET || IN_MULTICAST(addr) || IN_BADCLASS(addr); } #if 0 /* ----------------------------------------------------------------------------- * some_ip_ok - check a wordlist to see if it authorizes any * IP address(es). ----------------------------------------------------------------------------- */ static int some_ip_ok(struct wordlist *addrs) { for (; addrs != 0; addrs = addrs->next) { if (addrs->word[0] == '-') break; if (addrs->word[0] != '!') return 1; /* some IP address is allowed */ } return 0; } #endif /* ----------------------------------------------------------------------------- * 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; } } /* ----------------------------------------------------------------------------- * scan_authfile - Scan an authorization file for a secret suitable * for authenticating `client' on `server'. The return value is -1 * if no secret is found, otherwise >= 0. The return value has * NONWILD_CLIENT set if the secret didn't have "*" for the client, and * NONWILD_SERVER set if the secret didn't have "*" for the server. * Any following words on the line up to a "--" (i.e. address authorization * info) are placed in a wordlist and returned in *addrs. Any * following words (extra options) are placed in a wordlist and * returned in *opts. * We assume secret is NULL or points to MAXWORDLEN bytes of space. ----------------------------------------------------------------------------- */ int scan_authfile(struct ppp *ppp, FILE *f, char *client, char *server, char *secret, struct wordlist **addrs, struct wordlist **opts, char *filename) { int newline, xxx; int got_flag, best_flag; FILE *sf; struct wordlist *ap, *addr_list, *alist, **app; char word[MAXWORDLEN]; char atfile[MAXWORDLEN]; char lsecret[MAXWORDLEN]; if (addrs != NULL) *addrs = NULL; if (opts != NULL) *opts = NULL; addr_list = NULL; if (!getword(f, word, &newline, filename)) return -1; /* file is empty??? */ newline = 1; best_flag = -1; // should change this algo.... for (;;) { /* * Skip until we find a word at the start of a line. */ while (!newline && getword(f, word, &newline, filename)) ; if (!newline) break; /* got to end of file */ /* * Got a client - check if it's a match or a wildcard. */ got_flag = 0; if (client != NULL && strcmp(word, client) != 0 && !ISWILD(word)) { newline = 0; continue; } if (!ISWILD(word)) got_flag = NONWILD_CLIENT; #if 1 /* * Now get a server and check if it matches. */ if (!getword(f, word, &newline, filename)) break; if (newline) continue; if (!ISWILD(word)) { if (server != NULL && strcmp(word, server) != 0) continue; got_flag |= NONWILD_SERVER; } #else got_flag |= NONWILD_SERVER; #endif /* * Got some sort of a match - see if it's better than what * we have already. */ if (got_flag <= best_flag) continue; /* * Get the secret. */ if (!getword(f, word, &newline, filename)) break; if (newline) continue; /* * Special syntax: @filename means read secret from file. */ if (word[0] == '@') { strlcpy(atfile, word+1, sizeof(atfile)); if ((sf = fopen(atfile, "r")) == NULL) { warn(ppp, "can't open indirect secret file %s", atfile); continue; } //check_access(sf, atfile); if (!getword(sf, word, &xxx, atfile)) { warn(ppp, "no secret in indirect secret file %s", atfile); fclose(sf); continue; } fclose(sf); } if (secret != NULL) strlcpy(lsecret, word, sizeof(lsecret)); /* * Now read address authorization info and make a wordlist. */ app = &alist; for (;;) { if (!getword(f, word, &newline, filename) || newline) break; ap = (struct wordlist *) malloc(sizeof(struct wordlist)); if (ap == NULL) { //novm("authorized addresses"); // humm... return 0; } ap->word = strdup(word); if (ap->word == NULL) { //novm("authorized addresses"); // humm... return 0; } *app = ap; app = &ap->next; } *app = NULL; /* * This is the best so far; remember it. */ best_flag = got_flag; if (addr_list) free_wordlist(addr_list); addr_list = alist; if (secret != NULL) strlcpy(secret, lsecret, MAXWORDLEN); if (!newline) break; } /* scan for a -- word indicating the start of options */ for (app = &addr_list; (ap = *app) != NULL; app = &ap->next) if (strcmp(ap->word, "--") == 0) break; /* ap = start of options */ if (ap != NULL) { ap = ap->next; /* first option */ free(*app); /* free the "--" word */ *app = NULL; /* terminate addr list */ } if (opts != NULL) *opts = ap; else if (ap != NULL) free_wordlist(ap); if (addrs != NULL) *addrs = addr_list; else if (addr_list != NULL) free_wordlist(addr_list); return best_flag; } /* * Read a word from a file. * Words are delimited by white-space or by quotes (" or '). * Quotes, white-space and \ may be escaped with \. * \ is ignored. */ int getword(f, word, newlinep, filename) FILE *f; char *word; int *newlinep; char *filename; { int c, len, escape; int quoted, comment; int value, digit, got, n; #define isoctal(c) ((c) >= '0' && (c) < '8') *newlinep = 0; len = 0; escape = 0; comment = 0; /* * First skip white-space and comments. */ for (;;) { c = getc(f); if (c == EOF) break; /* * A newline means the end of a comment; backslash-newline * is ignored. Note that we cannot have escape && comment. */ if (c == '\n') { if (!escape) { *newlinep = 1; comment = 0; } else escape = 0; continue; } /* * Ignore characters other than newline in a comment. */ if (comment) continue; /* * If this character is escaped, we have a word start. */ if (escape) break; /* * If this is the escape character, look at the next character. */ if (c == '\\') { escape = 1; continue; } /* * If this is the start of a comment, ignore the rest of the line. */ if (c == '#') { comment = 1; continue; } /* * A non-whitespace character is the start of a word. */ if (!isspace(c)) break; } /* * Save the delimiter for quoted strings. */ if (!escape && (c == '"' || c == '\'')) { quoted = c; c = getc(f); } else quoted = 0; /* * Process characters until the end of the word. */ while (c != EOF) { if (escape) { /* * This character is escaped: backslash-newline is ignored, * various other characters indicate particular values * as for C backslash-escapes. */ escape = 0; if (c == '\n') { c = getc(f); continue; } got = 0; switch (c) { case 'a': value = '\a'; break; case 'b': value = '\b'; break; case 'f': value = '\f'; break; case 'n': value = '\n'; break; case 'r': value = '\r'; break; case 's': value = ' '; break; case 't': value = '\t'; break; default: if (isoctal(c)) { /* * \ddd octal sequence */ value = 0; for (n = 0; n < 3 && isoctal(c); ++n) { value = (value << 3) + (c & 07); c = getc(f); } got = 1; break; } if (c == 'x') { /* * \x sequence */ value = 0; c = getc(f); for (n = 0; n < 2 && isxdigit(c); ++n) { digit = toupper(c) - '0'; if (digit > 10) digit += '0' + 10 - 'A'; value = (value << 4) + digit; c = getc (f); } got = 1; break; } /* * Otherwise the character stands for itself. */ value = c; break; } /* * Store the resulting character for the escape sequence. */ if (len < MAXWORDLEN-1) word[len] = value; ++len; if (!got) c = getc(f); continue; } /* * Not escaped: see if we've reached the end of the word. */ if (quoted) { if (c == quoted) break; } else { if (isspace(c) || c == '#') { ungetc (c, f); break; } } /* * Backslash starts an escape sequence. */ if (c == '\\') { escape = 1; c = getc(f); continue; } /* * An ordinary character: store it in the word and get another. */ if (len < MAXWORDLEN-1) word[len] = c; ++len; c = getc(f); } /* * End of the word: check for errors. */ if (c == EOF) { if (ferror(f)) { if (errno == 0) errno = EIO; //option_error("Error reading %s: %m", filename); //die(1); return 0; } /* * If len is zero, then we didn't find a word before the * end of the file. */ if (len == 0) return 0; } /* * Warn if the word was too long, and append a terminating null. */ if (len >= MAXWORDLEN) { //option_error("warning: word in file %s too long (%.20s...)", // filename, word); len = MAXWORDLEN - 1; } word[len] = 0; return 1; #undef isoctal }