*/
#ifndef lint
-static char rcsid[] = "$Id: auth.c,v 1.1 1993/11/11 03:54:25 paulus Exp $";
+static char rcsid[] = "$Id: auth.c,v 1.21 1996/01/01 22:53:04 paulus 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 <sys/socket.h>
#include <netdb.h>
#include <netinet/in.h>
#include <arpa/inet.h>
-#include "ppp.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 "pathnames.h"
-#ifdef sparc
+#if defined(sun) && defined(sparc)
#include <alloca.h>
-#ifndef __GNUC__
-/* why alloca.h doesn't define what alloca() returns is a mystery */
-char *alloca __ARGS((int));
-#endif /*__GNUC__*/
#endif /*sparc*/
/* Used for storing a sequence of words. Usually malloced. */
#define FALSE 0
#define TRUE 1
-extern char user[];
-extern char passwd[];
-extern char devname[];
-extern char our_name[];
-extern char remote_name[];
-extern char hostname[];
-extern int uselogin;
-extern int usehostname;
-extern int auth_required;
-
/* Records which authentication operations haven't completed yet. */
-static int auth_pending[NPPP];
+static int auth_pending[NUM_PPP];
+
+/* Set if we have successfully called login() */
static int logged_in;
-static struct wordlist *addresses[NPPP];
+
+/* 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;
/* Bits in auth_pending[] */
#define UPAP_WITHPEER 1
#define CHAP_WITHPEER 4
#define CHAP_PEER 8
-/* Prototypes */
-void check_access __ARGS((FILE *, char *));
-
-static int login __ARGS((char *, char *, char **, int *));
-static void logout __ARGS((void));
-static int get_upap_passwd __ARGS((void));
-static int have_upap_secret __ARGS((void));
-static int have_chap_secret __ARGS((char *, char *));
-static int scan_authfile __ARGS((FILE *, char *, char *, char *,
+/* Prototypes for procedures local to this file. */
+
+static void network_phase __P((int));
+static void check_idle __P((caddr_t));
+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 __ARGS((struct wordlist *));
+static void free_wordlist __P((struct wordlist *));
-extern char *crypt __ARGS((char *, char *));
+extern char *crypt __P((char *, char *));
/*
* An Open on LCP has requested a change from Dead to Establish phase.
link_terminated(unit)
int unit;
{
+ if (phase == PHASE_DEAD)
+ return;
if (logged_in)
logout();
- if (lcp_wantoptions[unit].restart) {
- lcp_lowerdown(unit);
- lcp_lowerup(unit);
- } else
- EXIT(unit);
+ 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;
+{
+ int i;
+ struct protent *protp;
+
+ 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);
+ }
+ num_np_open = 0;
+ num_np_up = 0;
+ phase = PHASE_TERMINATE;
}
/*
lcp_options *wo = &lcp_wantoptions[unit];
lcp_options *go = &lcp_gotoptions[unit];
lcp_options *ho = &lcp_hisoptions[unit];
+ int i;
+ struct protent *protp;
+
+ /*
+ * Tell higher-level protocols that LCP is up.
+ */
+ for (i = 0; (protp = protocols[i]) != NULL; ++i)
+ if (protp->protocol != PPP_LCP && protp->enabled_flag
+ && protp->lowerup != NULL)
+ (*protp->lowerup)(unit);
if (auth_required && !(go->neg_chap || go->neg_upap)) {
/*
- * We wanted the peer to authenticate himself, and he refused:
- * tell him to go away.
+ * 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.
*/
- syslog(LOG_WARNING, "peer refused to authenticate");
- lcp_close(unit);
- return;
+ 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;
+ }
}
+ phase = PHASE_AUTHENTICATE;
auth = 0;
if (go->neg_chap) {
ChapAuthPeer(unit, our_name, go->chap_mdtype);
auth_pending[unit] = auth;
if (!auth)
- ipcp_open(unit);
+ network_phase(unit);
+}
+
+/*
+ * Proceed to the network phase.
+ */
+static void
+network_phase(unit)
+ int unit;
+{
+ int i;
+ struct protent *protp;
+
+ phase = PHASE_NETWORK;
+ for (i = 0; (protp = 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;
+ }
}
/*
/*
* Authentication failure: take the link down
*/
- lcp_close(unit);
+ lcp_close(unit, "Authentication failed");
+ phase = PHASE_TERMINATE;
}
/*
int bit;
switch (protocol) {
- case CHAP:
+ case PPP_CHAP:
bit = CHAP_PEER;
break;
- case UPAP:
+ case PPP_PAP:
bit = UPAP_PEER;
break;
default:
* proceed to the network phase.
*/
if ((auth_pending[unit] &= ~bit) == 0)
- ipcp_open(unit);
+ network_phase(unit);
}
/*
int bit;
switch (protocol) {
- case CHAP:
+ case PPP_CHAP:
bit = CHAP_WITHPEER;
break;
- case UPAP:
+ case PPP_PAP:
bit = UPAP_WITHPEER;
break;
default:
syslog(LOG_WARNING, "auth_peer_success: unknown protocol %x",
protocol);
+ bit = 0;
}
/*
* proceed to the network phase.
*/
if ((auth_pending[unit] &= ~bit) == 0)
- ipcp_open(unit);
+ network_phase(unit);
+}
+
+
+/*
+ * np_up - a network protocol has come up.
+ */
+void
+np_up(unit, proto)
+ int unit, proto;
+{
+ if (num_np_up == 0 && idle_time_limit > 0) {
+ TIMEOUT(check_idle, NULL, idle_time_limit);
+ }
+ ++num_np_up;
}
+/*
+ * np_down - a network protocol has gone down.
+ */
+void
+np_down(unit, proto)
+ int unit, proto;
+{
+ if (--num_np_up == 0 && idle_time_limit > 0) {
+ UNTIMEOUT(check_idle, NULL);
+ }
+}
/*
- * check_auth_options - called to check authentication options.
+ * np_finished - a network protocol has finished using the link.
*/
void
-check_auth_options()
+np_finished(unit, proto)
+ int unit, proto;
+{
+ if (--num_np_open <= 0) {
+ /* no further use for the link: shut up shop. */
+ 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(arg)
+ caddr_t arg;
+{
+ struct ppp_idle idle;
+ time_t itime;
+
+ if (!get_idle_time(0, &idle))
+ return;
+ itime = MIN(idle.xmit_idle, idle.recv_idle);
+ if (itime >= idle_time_limit) {
+ /* link is idle: shut it down. */
+ syslog(LOG_INFO, "Terminating connection due to lack of activity.");
+ lcp_close(0, "Link inactive");
+ } else {
+ TIMEOUT(check_idle, NULL, idle_time_limit - itime);
+ }
+}
+
+/*
+ * auth_check_options - called to check authentication options.
+ */
+void
+auth_check_options()
{
lcp_options *wo = &lcp_wantoptions[0];
lcp_options *ao = &lcp_allowoptions[0];
f = fopen(filename, "r");
if (f == NULL) {
if (!uselogin) {
- syslog(LOG_ERR, "Can't open upap password file %s: %m", filename);
+ syslog(LOG_ERR, "Can't open PAP 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 && strcmp(passwd, secret) != 0
+ || (secret[0] != 0 && (cryptpap || strcmp(passwd, secret) != 0)
&& strcmp(crypt(passwd, secret), secret) != 0)) {
- syslog(LOG_WARNING, "upap authentication failure for %s", user);
+ syslog(LOG_WARNING, "PAP 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);
+ syslog(LOG_WARNING, "PAP login failure for %s", user);
}
}
*/
if (attempts++ >= 10) {
syslog(LOG_WARNING, "%d LOGIN FAILURES ON %s, %s",
- attempts, devname, user);
+ attempts, devnam, user);
quit();
}
if (attempts > 3)
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.
*/
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 = strrchr(devname, '/');
- if (tty == NULL)
- tty = devname;
- else
- tty++;
+ tty = devnam;
+ if (strncmp(tty, "/dev/", 5) == 0)
+ tty += 5;
logwtmp(tty, user, ""); /* Add wtmp login entry */
logged_in = TRUE;
{
char *tty;
- tty = strrchr(devname, '/');
- if (tty == NULL)
- tty = devname;
- else
- 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
* on `server'. Either can be the null string, meaning we don't
* know the identity yet.
*/
-int
+static int
have_chap_secret(client, server)
char *client;
char *server;
char *server;
char *secret;
int *secret_len;
+ int save_addrs;
{
FILE *f;
int ret, len;
int
auth_ip_addr(unit, addr)
int unit;
- u_long addr;
+ u_int32_t addr;
{
- u_long a;
+ u_int32_t a, mask;
+ 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)
return 1; /* no restriction */
for (; addrs != NULL; addrs = addrs->next) {
/* "-" means no addresses authorized */
- if (strcmp(addrs->word, "-") == 0)
+ ptr_word = addrs->word;
+ if (strcmp(ptr_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);
+
+ accept = 1;
+ if (*ptr_word == '!') {
+ accept = 0;
+ ++ptr_word;
+ }
+
+ mask = ~ (u_int32_t) 0;
+ ptr_mask = strchr (ptr_word, '/');
+ if (ptr_mask != NULL) {
+ int bit_count;
+
+ bit_count = (int) strtol (ptr_mask+1, (char **) 0, 10);
+ if (bit_count <= 0 || bit_count > 32) {
+ syslog (LOG_WARNING,
+ "invalid address length %s in auth. address list",
+ ptr_mask);
continue;
- } else
- a = *(u_long *)hp->h_addr;
+ }
+ *ptr_mask = '\0';
+ mask <<= 32 - bit_count;
}
- if (addr == a)
- return 1;
+
+ hp = gethostbyname(ptr_word);
+ if (hp != NULL && hp->h_addrtype == AF_INET) {
+ a = *(u_int32_t *)hp->h_addr;
+ mask = ~ (u_int32_t) 0; /* are we sure we want this? */
+ } else {
+ np = getnetbyname (ptr_word);
+ if (np != NULL && np->n_addrtype == AF_INET)
+ a = htonl (*(u_int32_t *)np->n_net);
+ else
+ a = inet_addr (ptr_word);
+ }
+
+ if (ptr_mask != NULL)
+ *ptr_mask = '/';
+
+ if (a == -1L)
+ syslog (LOG_WARNING,
+ "unknown host %s in auth. address list",
+ addrs->word);
+ else
+ if (((addr ^ a) & mask) == 0)
+ return accept;
}
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.
*/
*/
if (addr_list)
free_wordlist(addr_list);
- addr_list = NULL;
+ addr_list = addr_last = NULL;
for (;;) {
if (!getword(f, word, &newline, filename) || newline)
break;