summaryrefslogtreecommitdiff
path: root/usr.sbin/pppd/auth.c
diff options
context:
space:
mode:
authorTheo de Raadt <deraadt@cvs.openbsd.org>1995-10-18 08:53:40 +0000
committerTheo de Raadt <deraadt@cvs.openbsd.org>1995-10-18 08:53:40 +0000
commitd6583bb2a13f329cf0332ef2570eb8bb8fc0e39c (patch)
treeece253b876159b39c620e62b6c9b1174642e070e /usr.sbin/pppd/auth.c
initial import of NetBSD tree
Diffstat (limited to 'usr.sbin/pppd/auth.c')
-rw-r--r--usr.sbin/pppd/auth.c934
1 files changed, 934 insertions, 0 deletions
diff --git a/usr.sbin/pppd/auth.c b/usr.sbin/pppd/auth.c
new file mode 100644
index 00000000000..2af78f6fc94
--- /dev/null
+++ b/usr.sbin/pppd/auth.c
@@ -0,0 +1,934 @@
+/*
+ * 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.
+ */
+
+#ifndef lint
+static char rcsid[] = "$Id: auth.c,v 1.1 1995/10/18 08:47:58 deraadt Exp $";
+#endif
+
+#include <stdio.h>
+#include <stddef.h>
+#include <stdlib.h>
+#include <syslog.h>
+#include <pwd.h>
+#include <string.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+
+#include <netdb.h>
+#include <netinet/in.h>
+#include <arpa/inet.h>
+
+#ifdef HAS_SHADOW
+#include <shadow.h>
+#include <shadow/pwauth.h>
+#ifndef PW_PPP
+#define PW_PPP PW_LOGIN
+#endif
+#endif
+
+#include "pppd.h"
+#include "fsm.h"
+#include "lcp.h"
+#include "upap.h"
+#include "chap.h"
+#include "ipcp.h"
+#include "ccp.h"
+#include "pathnames.h"
+
+#if defined(sun) && defined(sparc)
+#include <alloca.h>
+#endif /*sparc*/
+
+/* Used for storing a sequence of words. Usually malloced. */
+struct wordlist {
+ struct wordlist *next;
+ char word[1];
+};
+
+/* Bits in scan_authfile return value */
+#define NONWILD_SERVER 1
+#define NONWILD_CLIENT 2
+
+#define ISWILD(word) (word[0] == '*' && word[1] == 0)
+
+#define FALSE 0
+#define TRUE 1
+
+/* Records which authentication operations haven't completed yet. */
+static int auth_pending[NUM_PPP];
+static int logged_in;
+static struct wordlist *addresses[NUM_PPP];
+
+/* Bits in auth_pending[] */
+#define UPAP_WITHPEER 1
+#define UPAP_PEER 2
+#define CHAP_WITHPEER 4
+#define CHAP_PEER 8
+
+/* Prototypes */
+void check_access __P((FILE *, char *));
+
+static void network_phase __P((int));
+static int login __P((char *, char *, char **, int *));
+static void logout __P((void));
+static int null_login __P((int));
+static int get_upap_passwd __P((void));
+static int have_upap_secret __P((void));
+static int have_chap_secret __P((char *, char *));
+static int scan_authfile __P((FILE *, char *, char *, char *,
+ struct wordlist **, char *));
+static void free_wordlist __P((struct wordlist *));
+
+extern char *crypt __P((char *, char *));
+
+/*
+ * 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(unit)
+ int unit;
+{
+}
+
+/*
+ * LCP has terminated the link; go to the Dead phase and take the
+ * physical layer down.
+ */
+void
+link_terminated(unit)
+ int unit;
+{
+ if (phase == PHASE_DEAD)
+ return;
+ if (logged_in)
+ logout();
+ phase = PHASE_DEAD;
+ syslog(LOG_NOTICE, "Connection terminated.");
+}
+
+/*
+ * LCP has gone down; it will either die or try to re-establish.
+ */
+void
+link_down(unit)
+ int unit;
+{
+ ipcp_close(0);
+ ccp_close(0);
+ phase = PHASE_TERMINATE;
+}
+
+/*
+ * The link is established.
+ * Proceed to the Dead, Authenticate or Network phase as appropriate.
+ */
+void
+link_established(unit)
+ int unit;
+{
+ int auth;
+ lcp_options *wo = &lcp_wantoptions[unit];
+ lcp_options *go = &lcp_gotoptions[unit];
+ lcp_options *ho = &lcp_hisoptions[unit];
+
+ if (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)) {
+ syslog(LOG_WARNING, "peer refused to authenticate");
+ lcp_close(unit);
+ phase = PHASE_TERMINATE;
+ return;
+ }
+ }
+
+ phase = PHASE_AUTHENTICATE;
+ auth = 0;
+ if (go->neg_chap) {
+ ChapAuthPeer(unit, our_name, go->chap_mdtype);
+ auth |= CHAP_PEER;
+ } else if (go->neg_upap) {
+ upap_authpeer(unit);
+ auth |= UPAP_PEER;
+ }
+ if (ho->neg_chap) {
+ ChapAuthWithPeer(unit, our_name, ho->chap_mdtype);
+ auth |= CHAP_WITHPEER;
+ } else if (ho->neg_upap) {
+ upap_authwithpeer(unit, user, passwd);
+ auth |= UPAP_WITHPEER;
+ }
+ auth_pending[unit] = auth;
+
+ if (!auth)
+ network_phase(unit);
+}
+
+/*
+ * Proceed to the network phase.
+ */
+static void
+network_phase(unit)
+ int unit;
+{
+ phase = PHASE_NETWORK;
+ ipcp_open(unit);
+ ccp_open(unit);
+}
+
+/*
+ * The peer has failed to authenticate himself using `protocol'.
+ */
+void
+auth_peer_fail(unit, protocol)
+ int unit, protocol;
+{
+ /*
+ * Authentication failure: take the link down
+ */
+ lcp_close(unit);
+ phase = PHASE_TERMINATE;
+}
+
+/*
+ * The peer has been successfully authenticated using `protocol'.
+ */
+void
+auth_peer_success(unit, protocol)
+ int unit, protocol;
+{
+ int bit;
+
+ switch (protocol) {
+ case PPP_CHAP:
+ bit = CHAP_PEER;
+ break;
+ case PPP_PAP:
+ bit = UPAP_PEER;
+ break;
+ default:
+ syslog(LOG_WARNING, "auth_peer_success: unknown protocol %x",
+ protocol);
+ return;
+ }
+
+ /*
+ * If there is no more authentication still to be done,
+ * proceed to the network phase.
+ */
+ if ((auth_pending[unit] &= ~bit) == 0) {
+ phase = PHASE_NETWORK;
+ ipcp_open(unit);
+ ccp_open(unit);
+ }
+}
+
+/*
+ * We have failed to authenticate ourselves to the peer using `protocol'.
+ */
+void
+auth_withpeer_fail(unit, protocol)
+ int unit, protocol;
+{
+ /*
+ * 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(unit, protocol)
+ int unit, protocol;
+{
+ int bit;
+
+ switch (protocol) {
+ case PPP_CHAP:
+ bit = CHAP_WITHPEER;
+ break;
+ case PPP_PAP:
+ bit = UPAP_WITHPEER;
+ break;
+ default:
+ syslog(LOG_WARNING, "auth_peer_success: unknown protocol %x",
+ protocol);
+ bit = 0;
+ }
+
+ /*
+ * If there is no more authentication still being done,
+ * proceed to the network phase.
+ */
+ if ((auth_pending[unit] &= ~bit) == 0)
+ network_phase(unit);
+}
+
+
+/*
+ * check_auth_options - called to check authentication options.
+ */
+void
+check_auth_options()
+{
+ lcp_options *wo = &lcp_wantoptions[0];
+ lcp_options *ao = &lcp_allowoptions[0];
+
+ /* Default our_name to hostname, and user to our_name */
+ if (our_name[0] == 0 || usehostname)
+ strcpy(our_name, hostname);
+ if (user[0] == 0)
+ strcpy(user, our_name);
+
+ /* If authentication is required, ask peer for CHAP or PAP. */
+ if (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 ourselves and/or the peer.
+ */
+ if (ao->neg_upap && passwd[0] == 0 && !get_upap_passwd())
+ ao->neg_upap = 0;
+ if (wo->neg_upap && !uselogin && !have_upap_secret())
+ wo->neg_upap = 0;
+ if (ao->neg_chap && !have_chap_secret(our_name, remote_name))
+ ao->neg_chap = 0;
+ if (wo->neg_chap && !have_chap_secret(remote_name, our_name))
+ wo->neg_chap = 0;
+
+ if (auth_required && !wo->neg_chap && !wo->neg_upap) {
+ fprintf(stderr, "\
+pppd: peer authentication required but no authentication files accessible\n");
+ exit(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(unit, auser, userlen, apasswd, passwdlen, msg, msglen)
+ int unit;
+ char *auser;
+ int userlen;
+ char *apasswd;
+ int passwdlen;
+ char **msg;
+ int *msglen;
+{
+ int ret;
+ char *filename;
+ FILE *f;
+ struct wordlist *addrs;
+ char passwd[256], user[256];
+ char secret[MAXWORDLEN];
+ static int 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';
+
+ /*
+ * Open the file of upap secrets and scan for a suitable secret
+ * for authenticating this user.
+ */
+ filename = _PATH_UPAPFILE;
+ addrs = NULL;
+ ret = UPAP_AUTHACK;
+ f = fopen(filename, "r");
+ if (f == NULL) {
+ if (!uselogin) {
+ syslog(LOG_ERR, "Can't open upap password file %s: %m", filename);
+ ret = UPAP_AUTHNAK;
+ }
+
+ } else {
+ check_access(f, filename);
+ if (scan_authfile(f, user, our_name, secret, &addrs, filename) < 0
+ || (secret[0] != 0 && (cryptpap || strcmp(passwd, secret) != 0)
+ && strcmp(crypt(passwd, secret), secret) != 0)) {
+ syslog(LOG_WARNING, "upap authentication failure for %s", user);
+ ret = UPAP_AUTHNAK;
+ }
+ fclose(f);
+ }
+
+ if (uselogin && ret == UPAP_AUTHACK) {
+ ret = login(user, passwd, msg, msglen);
+ if (ret == UPAP_AUTHNAK) {
+ syslog(LOG_WARNING, "upap login failure for %s", user);
+ }
+ }
+
+ if (ret == UPAP_AUTHNAK) {
+ *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) {
+ syslog(LOG_WARNING, "%d LOGIN FAILURES ON %s, %s",
+ attempts, devnam, user);
+ quit();
+ }
+ if (attempts > 3)
+ sleep((u_int) (attempts - 3) * 5);
+ if (addrs != NULL)
+ free_wordlist(addrs);
+
+ } else {
+ attempts = 0; /* Reset count */
+ *msg = "Login ok";
+ *msglen = strlen(*msg);
+ if (addresses[unit] != NULL)
+ free_wordlist(addresses[unit]);
+ addresses[unit] = addrs;
+ }
+
+ return ret;
+}
+
+
+/*
+ * 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(user, passwd, msg, msglen)
+ char *user;
+ char *passwd;
+ char **msg;
+ int *msglen;
+{
+ struct passwd *pw;
+ char *epasswd;
+ char *tty;
+
+#ifdef HAS_SHADOW
+ struct spwd *spwd;
+ struct spwd *getspnam();
+#endif
+
+ if ((pw = getpwnam(user)) == NULL) {
+ return (UPAP_AUTHNAK);
+ }
+
+#ifdef HAS_SHADOW
+ if ((spwd = getspnam(user)) == NULL) {
+ pw->pw_passwd = "";
+ } else {
+ pw->pw_passwd = spwd->sp_pwdp;
+ }
+#endif
+
+ /*
+ * XXX If no passwd, let them login without one.
+ */
+ if (pw->pw_passwd == '\0') {
+ return (UPAP_AUTHACK);
+ }
+
+#ifdef HAS_SHADOW
+ if ((pw->pw_passwd && pw->pw_passwd[0] == '@'
+ && pw_auth (pw->pw_passwd+1, pw->pw_name, PW_PPP, NULL))
+ || !valid (passwd, pw)) {
+ return (UPAP_AUTHNAK);
+ }
+#else
+ epasswd = crypt(passwd, pw->pw_passwd);
+ if (strcmp(epasswd, pw->pw_passwd)) {
+ return (UPAP_AUTHNAK);
+ }
+#endif
+
+ syslog(LOG_INFO, "user %s logged in", user);
+
+ /*
+ * Write a wtmp entry for this user.
+ */
+ tty = devnam;
+ if (strncmp(tty, "/dev/", 5) == 0)
+ tty += 5;
+ logwtmp(tty, user, ""); /* Add wtmp login entry */
+ logged_in = TRUE;
+
+ return (UPAP_AUTHACK);
+}
+
+/*
+ * logout - Logout the user.
+ */
+static void
+logout()
+{
+ char *tty;
+
+ tty = devnam;
+ if (strncmp(tty, "/dev/", 5) == 0)
+ tty += 5;
+ logwtmp(tty, "", ""); /* Wipe out wtmp logout entry */
+ logged_in = FALSE;
+}
+
+
+/*
+ * 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(unit)
+ int unit;
+{
+ char *filename;
+ FILE *f;
+ int i, ret;
+ struct wordlist *addrs;
+ char secret[MAXWORDLEN];
+
+ /*
+ * Open the file of upap secrets and scan for a suitable secret.
+ * We don't accept a wildcard client.
+ */
+ filename = _PATH_UPAPFILE;
+ addrs = NULL;
+ f = fopen(filename, "r");
+ if (f == NULL)
+ return 0;
+ check_access(f, filename);
+
+ i = scan_authfile(f, "", our_name, secret, &addrs, filename);
+ ret = i >= 0 && (i & NONWILD_CLIENT) != 0 && secret[0] == 0;
+
+ if (ret) {
+ if (addresses[unit] != NULL)
+ free_wordlist(addresses[unit]);
+ addresses[unit] = addrs;
+ }
+
+ fclose(f);
+ return ret;
+}
+
+
+/*
+ * get_upap_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_upap_passwd()
+{
+ char *filename;
+ FILE *f;
+ struct wordlist *addrs;
+ char secret[MAXWORDLEN];
+
+ filename = _PATH_UPAPFILE;
+ addrs = NULL;
+ f = fopen(filename, "r");
+ if (f == NULL)
+ return 0;
+ check_access(f, filename);
+ if (scan_authfile(f, user, remote_name, secret, NULL, filename) < 0)
+ return 0;
+ strncpy(passwd, secret, MAXSECRETLEN);
+ passwd[MAXSECRETLEN-1] = 0;
+ return 1;
+}
+
+
+/*
+ * have_upap_secret - check whether we have a PAP file with any
+ * secrets that we could possibly use for authenticating the peer.
+ */
+static int
+have_upap_secret()
+{
+ FILE *f;
+ int ret;
+ char *filename;
+
+ filename = _PATH_UPAPFILE;
+ f = fopen(filename, "r");
+ if (f == NULL)
+ return 0;
+
+ ret = scan_authfile(f, NULL, our_name, NULL, NULL, filename);
+ fclose(f);
+ if (ret < 0)
+ return 0;
+
+ return 1;
+}
+
+
+/*
+ * 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(client, server)
+ char *client;
+ char *server;
+{
+ FILE *f;
+ int ret;
+ char *filename;
+
+ filename = _PATH_CHAPFILE;
+ f = fopen(filename, "r");
+ if (f == NULL)
+ return 0;
+
+ if (client[0] == 0)
+ client = NULL;
+ else if (server[0] == 0)
+ server = NULL;
+
+ ret = scan_authfile(f, client, server, NULL, NULL, filename);
+ fclose(f);
+ if (ret < 0)
+ return 0;
+
+ return 1;
+}
+
+
+/*
+ * 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(unit, client, server, secret, secret_len, save_addrs)
+ int unit;
+ char *client;
+ char *server;
+ char *secret;
+ int *secret_len;
+ int save_addrs;
+{
+ FILE *f;
+ int ret, len;
+ char *filename;
+ struct wordlist *addrs;
+ char secbuf[MAXWORDLEN];
+
+ filename = _PATH_CHAPFILE;
+ addrs = NULL;
+ secbuf[0] = 0;
+
+ f = fopen(filename, "r");
+ if (f == NULL) {
+ syslog(LOG_ERR, "Can't open chap secret file %s: %m", filename);
+ return 0;
+ }
+ check_access(f, filename);
+
+ ret = scan_authfile(f, client, server, secbuf, &addrs, filename);
+ fclose(f);
+ if (ret < 0)
+ return 0;
+
+ if (save_addrs) {
+ if (addresses[unit] != NULL)
+ free_wordlist(addresses[unit]);
+ addresses[unit] = addrs;
+ }
+
+ len = strlen(secbuf);
+ if (len > MAXSECRETLEN) {
+ syslog(LOG_ERR, "Secret for %s on %s is too long", client, server);
+ len = MAXSECRETLEN;
+ }
+ BCOPY(secbuf, secret, len);
+ *secret_len = len;
+
+ return 1;
+}
+
+/*
+ * 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(unit, addr)
+ int unit;
+ u_int32_t addr;
+{
+ u_int32_t a;
+ struct hostent *hp;
+ struct wordlist *addrs;
+
+ /* don't allow loopback or multicast address */
+ if (bad_ip_adrs(addr))
+ return 0;
+
+ if ((addrs = addresses[unit]) == NULL)
+ return 1; /* no restriction */
+
+ for (; addrs != NULL; addrs = addrs->next) {
+ /* "-" means no addresses authorized */
+ if (strcmp(addrs->word, "-") == 0)
+ break;
+ if ((a = inet_addr(addrs->word)) == -1) {
+ if ((hp = gethostbyname(addrs->word)) == NULL) {
+ syslog(LOG_WARNING, "unknown host %s in auth. address list",
+ addrs->word);
+ continue;
+ } else
+ a = *(u_int32_t *)hp->h_addr;
+ }
+ if (addr == a)
+ return 1;
+ }
+ return 0; /* not in list => can't have it */
+}
+
+/*
+ * 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(addr)
+ u_int32_t addr;
+{
+ addr = ntohl(addr);
+ return (addr >> IN_CLASSA_NSHIFT) == IN_LOOPBACKNET
+ || IN_MULTICAST(addr) || IN_BADCLASS(addr);
+}
+
+/*
+ * check_access - complain if a secret file has too-liberal permissions.
+ */
+void
+check_access(f, filename)
+ FILE *f;
+ char *filename;
+{
+ struct stat sbuf;
+
+ if (fstat(fileno(f), &sbuf) < 0) {
+ syslog(LOG_WARNING, "cannot stat secret file %s: %m", filename);
+ } else if ((sbuf.st_mode & (S_IRWXG | S_IRWXO)) != 0) {
+ syslog(LOG_WARNING, "Warning - secret file %s has world and/or group access", filename);
+ }
+}
+
+
+/*
+ * 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 (i.e. address authorization
+ * info) are placed in a wordlist and returned in *addrs.
+ */
+static int
+scan_authfile(f, client, server, secret, addrs, filename)
+ FILE *f;
+ char *client;
+ char *server;
+ char *secret;
+ struct wordlist **addrs;
+ char *filename;
+{
+ int newline, xxx;
+ int got_flag, best_flag;
+ FILE *sf;
+ struct wordlist *ap, *addr_list, *addr_last;
+ char word[MAXWORDLEN];
+ char atfile[MAXWORDLEN];
+
+ if (addrs != NULL)
+ *addrs = NULL;
+ addr_list = NULL;
+ if (!getword(f, word, &newline, filename))
+ return -1; /* file is empty??? */
+ newline = 1;
+ best_flag = -1;
+ 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;
+
+ /*
+ * Now get a server and check if it matches.
+ */
+ if (!getword(f, word, &newline, filename))
+ break;
+ if (newline)
+ continue;
+ if (server != NULL && strcmp(word, server) != 0 && !ISWILD(word))
+ continue;
+ if (!ISWILD(word))
+ got_flag |= NONWILD_SERVER;
+
+ /*
+ * 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] == '@') {
+ strcpy(atfile, word+1);
+ if ((sf = fopen(atfile, "r")) == NULL) {
+ syslog(LOG_WARNING, "can't open indirect secret file %s",
+ atfile);
+ continue;
+ }
+ check_access(sf, atfile);
+ if (!getword(sf, word, &xxx, atfile)) {
+ syslog(LOG_WARNING, "no secret in indirect secret file %s",
+ atfile);
+ fclose(sf);
+ continue;
+ }
+ fclose(sf);
+ }
+ if (secret != NULL)
+ strcpy(secret, word);
+
+ best_flag = got_flag;
+
+ /*
+ * Now read address authorization info and make a wordlist.
+ */
+ if (addr_list)
+ free_wordlist(addr_list);
+ addr_list = addr_last = NULL;
+ for (;;) {
+ if (!getword(f, word, &newline, filename) || newline)
+ break;
+ ap = (struct wordlist *) malloc(sizeof(struct wordlist)
+ + strlen(word));
+ if (ap == NULL)
+ novm("authorized addresses");
+ ap->next = NULL;
+ strcpy(ap->word, word);
+ if (addr_list == NULL)
+ addr_list = ap;
+ else
+ addr_last->next = ap;
+ addr_last = ap;
+ }
+ if (!newline)
+ break;
+ }
+
+ if (addrs != NULL)
+ *addrs = addr_list;
+ else if (addr_list != NULL)
+ free_wordlist(addr_list);
+
+ return best_flag;
+}
+
+/*
+ * free_wordlist - release memory allocated for a wordlist.
+ */
+static void
+free_wordlist(wp)
+ struct wordlist *wp;
+{
+ struct wordlist *next;
+
+ while (wp != NULL) {
+ next = wp->next;
+ free(wp);
+ wp = next;
+ }
+}