*/
#ifndef lint
-static char rcsid[] = "$Id: auth.c,v 1.21 1996/01/01 22:53:04 paulus Exp $";
+static char rcsid[] = "$Id: auth.c,v 1.26 1996/08/28 06:39:12 paulus Exp $";
#endif
#include <stdio.h>
#include <stddef.h>
#include <stdlib.h>
+#include <unistd.h>
#include <syslog.h>
#include <pwd.h>
#include <string.h>
#include <netinet/in.h>
#include <arpa/inet.h>
+#ifdef SVR4
+#include <crypt.h>
+#else
+#ifdef SUNOS4
+extern char *crypt();
+#endif
+#endif
+
+#ifdef USE_PAM
+#include <security/pam_appl.h>
+#include <security/pam_modules.h>
+#endif
+
#ifdef HAS_SHADOW
#include <shadow.h>
#include <shadow/pwauth.h>
#include "pppd.h"
#include "fsm.h"
#include "lcp.h"
+#include "ipcp.h"
#include "upap.h"
+#include "chap.h"
#include "pathnames.h"
#if defined(sun) && defined(sparc)
#define FALSE 0
#define TRUE 1
+/* The name by which the peer authenticated itself to us. */
+char peer_authname[MAXNAMELEN];
+
/* 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 have come up. */
static int num_np_up;
+/* Set if we got the contents of passwd[] from the pap-secrets file. */
+static int passwd_from_file;
+
/* Bits in auth_pending[] */
-#define UPAP_WITHPEER 1
-#define UPAP_PEER 2
+#define PAP_WITHPEER 1
+#define PAP_PEER 2
#define CHAP_WITHPEER 4
#define CHAP_PEER 8
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 int get_pap_passwd __P((char *));
+static int have_pap_secret __P((void));
+static int have_chap_secret __P((char *, char *, u_int32_t));
+static int ip_addr_check __P((u_int32_t, struct wordlist *));
+static int scan_authfile __P((FILE *, char *, char *, u_int32_t, char *,
+ struct wordlist **, char *));
static void free_wordlist __P((struct wordlist *));
-
-extern char *crypt __P((char *, char *));
+static void auth_script __P((char *));
/*
* An Open on LCP has requested a change from Dead to Establish phase.
int i;
struct protent *protp;
+ if (did_authup) {
+ auth_script(_PATH_AUTHDOWN);
+ did_authup = 0;
+ }
for (i = 0; (protp = 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);
+ (*protp->close)(unit, "LCP down");
}
num_np_open = 0;
num_np_up = 0;
if (!wo->neg_upap || !null_login(unit)) {
syslog(LOG_WARNING, "peer refused to authenticate");
lcp_close(unit, "peer refused to authenticate");
- phase = PHASE_TERMINATE;
return;
}
}
auth |= CHAP_PEER;
} else if (go->neg_upap) {
upap_authpeer(unit);
- auth |= UPAP_PEER;
+ auth |= PAP_PEER;
}
if (ho->neg_chap) {
- ChapAuthWithPeer(unit, our_name, ho->chap_mdtype);
+ ChapAuthWithPeer(unit, user, ho->chap_mdtype);
auth |= CHAP_WITHPEER;
} else if (ho->neg_upap) {
+ if (passwd[0] == 0) {
+ passwd_from_file = 1;
+ if (!get_pap_passwd(passwd))
+ syslog(LOG_ERR, "No secret found for PAP login");
+ }
upap_authwithpeer(unit, user, passwd);
- auth |= UPAP_WITHPEER;
+ auth |= PAP_WITHPEER;
}
auth_pending[unit] = auth;
{
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) {
+ auth_script(_PATH_AUTHUP);
+ did_authup = 1;
+ }
phase = PHASE_NETWORK;
+#if 0
+ if (!demand)
+ set_filters(&pass_filter, &active_filter);
+#endif
for (i = 0; (protp = protocols[i]) != NULL; ++i)
if (protp->protocol < 0xC000 && protp->enabled_flag
&& protp->open != NULL) {
* Authentication failure: take the link down
*/
lcp_close(unit, "Authentication failed");
- phase = PHASE_TERMINATE;
}
/*
* The peer has been successfully authenticated using `protocol'.
*/
void
-auth_peer_success(unit, protocol)
+auth_peer_success(unit, protocol, name, namelen)
int unit, protocol;
+ char *name;
+ int namelen;
{
int bit;
bit = CHAP_PEER;
break;
case PPP_PAP:
- bit = UPAP_PEER;
+ bit = PAP_PEER;
break;
default:
syslog(LOG_WARNING, "auth_peer_success: unknown protocol %x",
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 phase.
auth_withpeer_fail(unit, protocol)
int unit, protocol;
{
+ if (passwd_from_file)
+ BZERO(passwd, MAXSECRETLEN);
/*
* We've failed to authenticate ourselves to our peer.
* He'll probably take the link down, and there's not much
bit = CHAP_WITHPEER;
break;
case PPP_PAP:
- bit = UPAP_WITHPEER;
+ if (passwd_from_file)
+ BZERO(passwd, MAXSECRETLEN);
+ bit = PAP_WITHPEER;
break;
default:
syslog(LOG_WARNING, "auth_peer_success: unknown protocol %x",
if (itime >= idle_time_limit) {
/* link is idle: shut it down. */
syslog(LOG_INFO, "Terminating connection due to lack of activity.");
+ need_holdoff = 0;
lcp_close(0, "Link inactive");
} else {
TIMEOUT(check_idle, NULL, idle_time_limit - itime);
auth_check_options()
{
lcp_options *wo = &lcp_wantoptions[0];
- lcp_options *ao = &lcp_allowoptions[0];
+ int can_auth;
+ ipcp_options *ipwo = &ipcp_wantoptions[0];
+ u_int32_t remote;
+
+ /* Check that we are running as root. */
+ if (geteuid() != 0) {
+ option_error("must be run with root privileges");
+ exit(1);
+ }
/* Default our_name to hostname, and user to our_name */
if (our_name[0] == 0 || usehostname)
/*
* Check whether we have appropriate secrets to use
- * to authenticate ourselves and/or the peer.
+ * to authenticate 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;
+ can_auth = wo->neg_upap && (uselogin || have_pap_secret());
+ if (!can_auth && wo->neg_chap) {
+ remote = ipwo->accept_remote? 0: ipwo->hisaddr;
+ can_auth = have_chap_secret(remote_name, our_name, remote);
+ }
- if (auth_required && !wo->neg_chap && !wo->neg_upap) {
- fprintf(stderr, "\
-pppd: peer authentication required but no authentication files accessible\n");
+ if (auth_required && !can_auth) {
+ option_error("peer authentication required but no suitable secret(s) found\n");
exit(1);
}
+ /*
+ * Check whether the user tried to override certain values
+ * set by root.
+ */
+ if (!auth_required && auth_req_info.priv > 0) {
+ if (!default_device && devnam_info.priv == 0) {
+ option_error("can't override device name when noauth option used");
+ exit(1);
+ }
+ if (connector != NULL && connector_info.priv == 0
+ || disconnector != NULL && disconnector_info.priv == 0
+ || welcomer != NULL && welcomer_info.priv == 0) {
+ option_error("can't override connect, disconnect or welcome");
+ option_error("option values when noauth option used");
+ exit(1);
+ }
+ }
+}
+
+/*
+ * 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(unit)
+ int unit;
+{
+ lcp_options *go = &lcp_gotoptions[unit];
+ lcp_options *ao = &lcp_allowoptions[0];
+ ipcp_options *ipwo = &ipcp_wantoptions[0];
+ u_int32_t remote;
+
+ ao->neg_upap = !refuse_pap && (passwd[0] != 0 || get_pap_passwd(NULL));
+ ao->neg_chap = !refuse_chap
+ && have_chap_secret(user, remote_name, (u_int32_t)0);
+
+ if (go->neg_upap && !uselogin && !have_pap_secret())
+ go->neg_upap = 0;
+ if (go->neg_chap) {
+ remote = ipwo->accept_remote? 0: ipwo->hisaddr;
+ if (!have_chap_secret(remote_name, our_name, remote))
+ go->neg_chap = 0;
+ }
+
}
char *filename;
FILE *f;
struct wordlist *addrs;
+ u_int32_t remote;
+ ipcp_options *ipwo = &ipcp_wantoptions[unit];
char passwd[256], user[256];
char secret[MAXWORDLEN];
static int attempts = 0;
passwd[passwdlen] = '\0';
BCOPY(auser, user, userlen);
user[userlen] = '\0';
+ *msg = (char *) 0;
/*
- * Open the file of upap secrets and scan for a suitable secret
+ * Open the file of pap secrets and scan for a suitable secret
* for authenticating this user.
*/
filename = _PATH_UPAPFILE;
} else {
check_access(f, filename);
- if (scan_authfile(f, user, our_name, secret, &addrs, filename) < 0
+ remote = ipwo->accept_remote? 0: ipwo->hisaddr;
+ if (scan_authfile(f, user, our_name, remote,
+ secret, &addrs, filename) < 0
|| (secret[0] != 0 && (cryptpap || strcmp(passwd, secret) != 0)
&& strcmp(crypt(passwd, secret), secret) != 0)) {
syslog(LOG_WARNING, "PAP authentication failure for %s", user);
}
if (ret == UPAP_AUTHNAK) {
- *msg = "Login incorrect";
+ if (*msg == (char *) 0)
+ *msg = "Login incorrect";
*msglen = strlen(*msg);
/*
* Frustrate passwd stealer programs.
} else {
attempts = 0; /* Reset count */
- *msg = "Login ok";
+ if (*msg == (char *) 0)
+ *msg = "Login ok";
*msglen = strlen(*msg);
if (addresses[unit] != NULL)
free_wordlist(addresses[unit]);
addresses[unit] = addrs;
}
+ BZERO(passwd, sizeof(passwd));
+ BZERO(secret, sizeof(secret));
+
return ret;
}
+#ifdef HAS_SHADOW
+/**************
+ * This function was lifted from the shadow-3.3.2 version by John Haugh II.
+ * It is included because the function was not in the standard libshadow
+ * library. If it is included in the library then I can remove it from here.
+ */
+
+#define DAY (24L*3600L)
+/*
+ * isexpired - determine if account is expired yet
+ *
+ * isexpired calculates the expiration date based on the
+ * password expiration criteria.
+ */
+
+/*ARGSUSED*/
+int
+isexpired (pw, sp)
+struct passwd *pw;
+struct spwd *sp;
+{
+ long clock;
+
+ clock = time ((time_t *) 0) / DAY;
+
+ /*
+ * Quick and easy - there is an expired account field
+ * along with an inactive account field. Do the expired
+ * one first since it is worse.
+ */
+
+ if (sp->sp_expire > 0 && sp->sp_expire < clock)
+ return 3;
+
+ if (sp->sp_inact > 0 && sp->sp_lstchg > 0 && sp->sp_max > 0 &&
+ sp->sp_inact + sp->sp_lstchg + sp->sp_max < clock)
+ return 2;
+
+ /*
+ * The last and max fields must be present for an account
+ * to have an expired password. A maximum of >10000 days
+ * is considered to be infinite.
+ */
+
+ if (sp->sp_lstchg == -1 ||
+ sp->sp_max == -1 || sp->sp_max >= 10000L)
+ return 0;
+
+ /*
+ * Calculate today's day and the day on which the password
+ * is going to expire. If that date has already passed,
+ * the password has expired.
+ */
+
+ if (sp->sp_lstchg + sp->sp_max < clock)
+ return 1;
+
+ return 0;
+}
+#endif
+
+
+/*
+ * This function is needed for PAM. However, it should not be called.
+ * If it is, return the error code.
+ */
+
+#ifdef USE_PAM
+static int pam_conv(int num_msg, const struct pam_message **msg,
+ struct pam_response **resp, void *appdata_ptr)
+{
+ return PAM_CONV_ERR;
+}
+#endif
/*
* login - Check the user name and password against the system
* UPAP_AUTHACK: Login succeeded.
* In either case, msg points to an appropriate message.
*/
+
static int
login(user, passwd, msg, msglen)
char *user;
char **msg;
int *msglen;
{
+ char *tty;
+
+#ifdef USE_PAM
+ struct pam_conv pam_conversation;
+ pam_handle_t *pamh;
+ int pam_error;
+ char *pass;
+ char *dev;
+/*
+ * Fill the pam_conversion structure
+ */
+ memset (&pam_conversation, '\0', sizeof (struct pam_conv));
+ pam_conversation.conv = &pam_conv;
+
+ pam_error = pam_start ("ppp", user, &pam_conversation, &pamh);
+ if (pam_error != PAM_SUCCESS) {
+ *msg = (char *) pam_strerror (pam_error);
+ return UPAP_AUTHNAK;
+ }
+/*
+ * Define the fields for the credintial validation
+ */
+ (void) pam_set_item (pamh, PAM_AUTHTOK, passwd);
+ (void) pam_set_item (pamh, PAM_TTY, devnam);
+/*
+ * Validate the user
+ */
+ pam_error = pam_authenticate (pamh, PAM_SILENT);
+ if (pam_error == PAM_SUCCESS)
+ pam_error = pam_acct_mgmt (pamh, PAM_SILENT);
+
+ *msg = (char *) pam_strerror (pam_error);
+/*
+ * Clean up the mess
+ */
+ (void) pam_end (pamh, pam_error);
+
+ if (pam_error != PAM_SUCCESS)
+ return UPAP_AUTHNAK;
+/*
+ * Use the non-PAM methods directly
+ */
+#else /* #ifdef USE_PAM */
+
struct passwd *pw;
char *epasswd;
- char *tty;
#ifdef HAS_SHADOW
struct spwd *spwd;
}
#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);
+ if (pw->pw_passwd) {
+ if (pw->pw_passwd[0] == '@') {
+ if (pw_auth (pw->pw_passwd+1, pw->pw_name, PW_PPP, NULL)) {
+ return (UPAP_AUTHNAK);
+ }
+ } else {
+ epasswd = pw_encrypt(passwd, pw->pw_passwd);
+ if (strcmp(epasswd, pw->pw_passwd)) {
+ return (UPAP_AUTHNAK);
+ }
+ }
+ /* check the age of the password entry */
+ if (spwd && (isexpired (pw, spwd) != 0)) {
+ return (UPAP_AUTHNAK);
+ }
}
#else
epasswd = crypt(passwd, pw->pw_passwd);
return (UPAP_AUTHNAK);
}
#endif
+#endif /* #ifdef USE_PAM */
syslog(LOG_INFO, "user %s logged in", user);
tty = devnam;
if (strncmp(tty, "/dev/", 5) == 0)
tty += 5;
- logwtmp(tty, user, ""); /* Add wtmp login entry */
+ logwtmp(tty, user, remote_name); /* Add wtmp login entry */
logged_in = TRUE;
return (UPAP_AUTHACK);
char secret[MAXWORDLEN];
/*
- * Open the file of upap secrets and scan for a suitable secret.
+ * Open the file of pap secrets and scan for a suitable secret.
* We don't accept a wildcard client.
*/
filename = _PATH_UPAPFILE;
return 0;
check_access(f, filename);
- i = scan_authfile(f, "", our_name, secret, &addrs, filename);
+ i = scan_authfile(f, "", our_name, (u_int32_t)0, secret, &addrs, filename);
ret = i >= 0 && (i & NONWILD_CLIENT) != 0 && secret[0] == 0;
+ BZERO(secret, sizeof(secret));
if (ret) {
if (addresses[unit] != NULL)
/*
- * get_upap_passwd - get a password for authenticating ourselves with
+ * 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_upap_passwd()
+get_pap_passwd(char *passwd)
{
char *filename;
FILE *f;
if (f == NULL)
return 0;
check_access(f, filename);
- if (scan_authfile(f, user, remote_name, secret, NULL, filename) < 0)
+ if (scan_authfile(f, user,
+ remote_name[0]? remote_name: NULL,
+ (u_int32_t)0, secret, NULL, filename) < 0)
return 0;
- strncpy(passwd, secret, MAXSECRETLEN);
- passwd[MAXSECRETLEN-1] = 0;
+ if (passwd != NULL) {
+ strncpy(passwd, secret, MAXSECRETLEN);
+ passwd[MAXSECRETLEN-1] = 0;
+ }
+ BZERO(secret, sizeof(secret));
return 1;
}
/*
- * have_upap_secret - check whether we have a PAP file with any
+ * 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_upap_secret()
+have_pap_secret()
{
FILE *f;
int ret;
char *filename;
+ ipcp_options *ipwo = &ipcp_wantoptions[0];
+ u_int32_t remote;
filename = _PATH_UPAPFILE;
f = fopen(filename, "r");
if (f == NULL)
return 0;
- ret = scan_authfile(f, NULL, our_name, NULL, NULL, filename);
+ remote = ipwo->accept_remote? 0: ipwo->hisaddr;
+ ret = scan_authfile(f, NULL, our_name, remote, NULL, NULL, filename);
fclose(f);
if (ret < 0)
return 0;
* know the identity yet.
*/
static int
-have_chap_secret(client, server)
+have_chap_secret(client, server, remote)
char *client;
char *server;
+ u_int32_t remote;
{
FILE *f;
int ret;
else if (server[0] == 0)
server = NULL;
- ret = scan_authfile(f, client, server, NULL, NULL, filename);
+ ret = scan_authfile(f, client, server, remote, NULL, NULL, filename);
fclose(f);
if (ret < 0)
return 0;
}
check_access(f, filename);
- ret = scan_authfile(f, client, server, secbuf, &addrs, filename);
+ ret = scan_authfile(f, client, server, (u_int32_t)0,
+ secbuf, &addrs, filename);
fclose(f);
if (ret < 0)
return 0;
len = MAXSECRETLEN;
}
BCOPY(secbuf, secret, len);
+ BZERO(secbuf, sizeof(secbuf));
*secret_len = len;
return 1;
int unit;
u_int32_t addr;
{
- u_int32_t a, mask;
+ return ip_addr_check(addr, addresses[unit]);
+}
+
+static int
+ip_addr_check(addr, addrs)
+ u_int32_t addr;
+ struct wordlist *addrs;
+{
+ u_int32_t a, mask, ah;
int accept;
char *ptr_word, *ptr_mask;
struct hostent *hp;
struct netent *np;
- struct wordlist *addrs;
/* don't allow loopback or multicast address */
if (bad_ip_adrs(addr))
return 0;
- if ((addrs = addresses[unit]) == NULL)
+ if (addrs == NULL)
return 1; /* no restriction */
for (; addrs != NULL; addrs = addrs->next) {
a = htonl (*(u_int32_t *)np->n_net);
else
a = inet_addr (ptr_word);
+ 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;
+ }
}
if (ptr_mask != NULL)
"unknown host %s in auth. address list",
addrs->word);
else
- if (((addr ^ a) & mask) == 0)
+ if (((addr ^ a) & htonl(mask)) == 0)
return accept;
}
return 0; /* not in list => can't have it */
* info) are placed in a wordlist and returned in *addrs.
*/
static int
-scan_authfile(f, client, server, secret, addrs, filename)
+scan_authfile(f, client, server, ipaddr, secret, addrs, filename)
FILE *f;
char *client;
char *server;
+ u_int32_t ipaddr;
char *secret;
struct wordlist **addrs;
char *filename;
int newline, xxx;
int got_flag, best_flag;
FILE *sf;
- struct wordlist *ap, *addr_list, *addr_last;
+ struct wordlist *ap, *addr_list, *alist, *alast;
char word[MAXWORDLEN];
char atfile[MAXWORDLEN];
+ char lsecret[MAXWORDLEN];
if (addrs != NULL)
*addrs = NULL;
fclose(sf);
}
if (secret != NULL)
- strcpy(secret, word);
-
- best_flag = got_flag;
+ strcpy(lsecret, word);
/*
* Now read address authorization info and make a wordlist.
*/
- if (addr_list)
- free_wordlist(addr_list);
- addr_list = addr_last = NULL;
+ alist = alast = NULL;
for (;;) {
if (!getword(f, word, &newline, filename) || newline)
break;
novm("authorized addresses");
ap->next = NULL;
strcpy(ap->word, word);
- if (addr_list == NULL)
- addr_list = ap;
+ if (alist == NULL)
+ alist = ap;
else
- addr_last->next = ap;
- addr_last = ap;
+ alast->next = ap;
+ alast = ap;
}
+
+ /*
+ * Check if the given IP address is allowed by the wordlist.
+ */
+ if (ipaddr != 0 && !ip_addr_check(ipaddr, alist)) {
+ free_wordlist(alist);
+ continue;
+ }
+
+ /*
+ * 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)
+ strcpy(secret, lsecret);
+
if (!newline)
break;
}
wp = next;
}
}
+
+/*
+ * auth_script - execute a script with arguments
+ * interface-name peer-name real-user tty speed
+ */
+static void
+auth_script(script)
+ char *script;
+{
+ char strspeed[32];
+ struct passwd *pw;
+ char struid[32];
+ char *user_name;
+ char *argv[8];
+
+ if ((pw = getpwuid(getuid())) != NULL && pw->pw_name != NULL)
+ user_name = pw->pw_name;
+ else {
+ sprintf(struid, "%d", getuid());
+ user_name = struid;
+ }
+ sprintf(strspeed, "%d", baud_rate);
+
+ argv[0] = script;
+ argv[1] = ifname;
+ argv[2] = peer_authname;
+ argv[3] = user_name;
+ argv[4] = devnam;
+ argv[5] = strspeed;
+ argv[6] = NULL;
+
+ run_program(script, argv, 0);
+}
projects / ppp.git / blobdiff