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isdn4k-utils/ipppd/auth.c

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/*
* auth.c - PPP authentication and phase control.
*
* Fairly patched version for isdn4linux
* copyright (c) 1995,1996,1997 of all patches by Michael Hipp
* still no warranties (see disclaimer)
*
* Copyright (c) 1993 The Australian National University.
* All rights reserved.
*
* 2000-07-25 Callback improvements by richard.kunze@web.de
*
* 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.
*/
char auth_rcsid[] = "$Id: auth.c,v 1.17 2000/07/25 20:23:51 kai Exp $";
#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 <unistd.h>
#include <netdb.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#if defined __GLIBC__ && __GLIBC__ >= 2
# include <crypt.h>
#endif
#include "config.h"
#ifdef HAVE_SHADOW_H
#include <shadow.h>
#endif
#ifdef RADIUS
#include <radiusclient.h>
int radius_pap_auth __P((int, char *, char *, char **, int *));
extern int auth_order ;
extern int idle_time_limit ;
extern int default_idle_time_limit ;
extern int session_time_limit ;
extern int default_session_time_limit ;
#endif
#include "fsm.h"
#include "ipppd.h"
#include "lcp.h"
#include "upap.h"
#include "chap.h"
#include "cbcp.h"
#include "ipcp.h"
#include "ipxcp.h"
#include "ccp.h"
#include "pathnames.h"
#if defined(sun) && defined(sparc)
#include <alloca.h>
#endif /*sparc*/
/* 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
/* 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 void callback_phase __P((int));
static int link_lastlink(int);
static int check_login __P((char *, char *, char **, int *,int));
static void do_logout __P((int));
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 *));
static void auth_script __P((int,char *,int));
/*
* 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)
{
}
/*
* LCP has terminated the link; go to the Dead phase and take the
* physical layer down.
*/
void link_terminated(int linkunit)
{
#ifdef RADIUS
extern u_int32_t default_hisaddr;
extern u_int32_t default_ouraddr;
extern u_int32_t default_netmask;
struct in_addr hisifaddr;
struct in_addr ourifaddr;
#endif
if(lns[linkunit].auth_up_script)
auth_script(linkunit,_PATH_AUTHDOWN,0);
if (lns[linkunit].phase == PHASE_DEAD)
return;
if (lns[linkunit].logged_in) {
do_logout(linkunit);
lns[linkunit].logged_in = 0;
}
#ifdef RADIUS
if (lns[linkunit].radius_in )
{
lns[linkunit].radius_in = FALSE ;
if ( useradacct )
radius_acct_stop(linkunit) ;
}
/* reset some parameters to their default (option-parsed) values */
session_time_limit = default_session_time_limit ;
idle_time_limit = default_idle_time_limit ;
/* and reset IP addresses to their default values */
hisifaddr.s_addr = default_hisaddr ? default_hisaddr : ipcp_wantoptions[linkunit].hisaddr ;
ourifaddr.s_addr = default_ouraddr ? default_ouraddr : ipcp_wantoptions[linkunit].ouraddr ;
syslog(LOG_DEBUG,
"reseting remote ippp interface addresses for linkunit %d [ifunit %d] to %s:%s\n",
linkunit,
lns[linkunit].ifunit,
inet_ntoa(ourifaddr),
inet_ntoa(hisifaddr)
);
sifaddr(linkunit,
default_ouraddr ? default_ouraddr :ipcp_wantoptions[linkunit].ouraddr,
default_hisaddr ? default_hisaddr : ipcp_wantoptions[linkunit].hisaddr,
default_netmask ? default_netmask : 0xffffffff);
#endif
lns[linkunit].phase = PHASE_DEAD;
syslog(LOG_NOTICE, "Connection terminated.");
}
/*
* LCP has gone down; it will either die or try to re-establish.
*/
void link_down(int unit)
{
if(lns[unit].ccp_l_unit >= 0) {
(*ccp_link_protent.lowerdown)(lns[unit].ccp_l_unit);
(*ccp_link_protent.close)(lns[unit].ccp_l_unit,"link went down");
ccp_freeunit(lns[unit].ccp_l_unit);
lns[unit].ccp_l_unit = -1;
}
if(link_lastlink(unit)) {
if(lns[unit].ccp_unit >= 0) {
(*ccp_protent.lowerdown)(lns[unit].ccp_unit);
(*ccp_protent.close)(lns[unit].ccp_unit,"link went down");
ccp_freeunit(lns[unit].ccp_unit);
lns[unit].ccp_unit = -1;
}
if(lns[unit].ipcp_unit >= 0) {
(*ipcp_protent.lowerdown)(lns[unit].ipcp_unit);
(*ipcp_protent.close)(lns[unit].ipcp_unit,"link went down");
ipcp_freeunit(lns[unit].ipcp_unit);
lns[unit].ipcp_unit = -1;
}
if(lns[unit].cbcp_unit >= 0) {
(*cbcp_protent.lowerdown)(lns[unit].cbcp_unit);
(*cbcp_protent.close)(lns[unit].cbcp_unit,"link went down");
lns[unit].cbcp_unit = -1;
}
if(lns[unit].ipxcp_unit >= 0)
{
(*ipxcp_protent.lowerdown)(lns[unit].ipxcp_unit);
(*ipxcp_protent.close)(lns[unit].ipxcp_unit,"link went down");
ipxcp_freeunit(lns[unit].ipxcp_unit);
lns[unit].ipxcp_unit = -1;
}
}
else {
struct link_struct *q;
int i; /* bugcheck, stop after 1024 links */
for(i=1024,q=lns[unit].bundle_next;!i && q!=&lns[unit];q=q->bundle_next,i--) {
if(q->bundle_next == &lns[unit])
break;
}
if(!i || q == &lns[unit]) {
syslog(LOG_ERR,"Error on 'unbundling' link");
}
else {
/*
* maybe the dead link was our communication link -> set a valid 'fd'
*/
ipcp_fsm[lns[unit].ipcp_unit].unit = q->unit;
ccp_fsm[lns[unit].ccp_unit].unit = q->unit;
ipxcp_fsm[lns[unit].ipxcp_unit].unit = q->unit;
q->bundle_next = lns[unit].bundle_next;
lns[unit].bundle_next = &lns[unit];
}
}
lns[unit].phase = PHASE_TERMINATE;
}
/*
* check whether 'unit' is the last in the bundle
*/
static int link_lastlink(int unit)
{
if(lns[unit].bundle_next == &lns[unit])
return 1;
else
return 0;
}
/*
* The link is established.
* Proceed to the Dead, Authenticate or Network phase as appropriate.
*/
void link_established(int linkunit)
{
int auth;
lcp_options *wo = &lcp_wantoptions[ lns[linkunit].lcp_unit ];
lcp_options *go = &lcp_gotoptions[ lns[linkunit].lcp_unit ];
lcp_options *ho = &lcp_hisoptions[ lns[linkunit].lcp_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(linkunit)) {
syslog(LOG_WARNING, "peer refused to authenticate");
lcp_close(lns[linkunit].lcp_unit,"peer refused to authenticate");
lns[linkunit].phase = PHASE_TERMINATE;
return;
}
}
lns[linkunit].phase = PHASE_AUTHENTICATE;
auth = 0;
if (go->neg_chap) {
ChapAuthPeer(lns[linkunit].chap_unit, our_name, go->chap_mdtype);
auth |= CHAP_PEER;
} else if (go->neg_upap) {
upap_authpeer(lns[linkunit].upap_unit);
auth |= UPAP_PEER;
}
if (ho->neg_chap) {
ChapAuthWithPeer(lns[linkunit].chap_unit, our_name, ho->chap_mdtype);
auth |= CHAP_WITHPEER;
} else if (ho->neg_upap) {
upap_authwithpeer(lns[linkunit].upap_unit, user, passwd);
auth |= UPAP_WITHPEER;
}
lns[linkunit].auth_pending = auth;
if (!auth)
callback_phase(linkunit);
}
/*
* Proceed to the network phase.
*/
static void network_phase(int linkunit)
{
int lcp_unit = lns[linkunit].lcp_unit;
lcp_options *go=&lcp_gotoptions[lcp_unit],*ho=&lcp_hisoptions[lcp_unit];
int higher_up = 1;
int discr,i;
if(go->neg_mpmrru || go->neg_mpshortseq)
go->neg_mp = 1;
if(ho->neg_mpmrru || ho->neg_mpshortseq)
ho->neg_mp = 1;
syslog(LOG_INFO,"MPPP negotiation, He: %s We: %s",go->neg_mp?"Yes":"No",ho->neg_mp?"Yes":"No");
if(go->neg_mp && ho->neg_mp)
for(i=0;i<numdev && higher_up;i++)
{
if(i != linkunit && lns[i].phase == PHASE_NETWORK)
{
if(lcp_gotoptions[i].neg_mp && lcp_hisoptions[i].neg_mp)
{
discr = lcp_hisoptions[i].neg_mpdiscr ? 1 : 0;
if(ho->neg_mpdiscr)
discr++;
syslog(LOG_INFO,"ipppd[%d]: discr: %d\n",linkunit,discr);
switch(discr)
{
case 1: /* one peer has a discriminator, the other not */
break;
case 2:
/*
* maybe, we should check our side, too
* (but currently we use always the same discriminator)
*/
if(ho->mp_alen != lcp_hisoptions[i].mp_alen || ho->mp_class != lcp_hisoptions[i].mp_class)
break;
syslog(LOG_INFO,"ipppd[%d]: passed 1\n",linkunit);
if(memcmp(ho->mp_addr,lcp_hisoptions[i].mp_addr,ho->mp_alen))
break;
syslog(LOG_INFO,"ipppd[%d]: passed 2\n",linkunit);
case 0:
/*
* login check when peer has authentification
*/
if(go->neg_chap)
{
syslog(LOG_INFO,"ipppd[%d]: chap-check: NOT IMPLEMENTED YET\n",linkunit);
}
else if(go->neg_upap)
{
int l;
syslog(LOG_INFO,"ipppd[%d]: pap-check\n",linkunit);
if((l=upap[lns[linkunit].upap_unit].us_ruserlen) == upap[lns[i].upap_unit].us_ruserlen)
if(strncmp(upap[lns[linkunit].upap_unit].us_ruser,upap[lns[i].upap_unit].us_ruser,l))
{
syslog(LOG_INFO,"Making no bundle because of different login names");
break;
}
}
syslog(LOG_INFO,"ipppd[%d]: pap/chap-check passed\n",linkunit);
higher_up = 0;
/*
* ok: found a valid bundle
*/
syslog(LOG_INFO,"ok, found a valid bundle with linkunit %d",i);
lns[linkunit].bundle_next = lns[i].bundle_next;
lns[i].bundle_next = &lns[linkunit];
lns[linkunit].ifunit = lns[i].ifunit;
lns[linkunit].master = i;
lns[linkunit].ipcp_unit = lns[i].ipcp_unit; /* use fsm state of other link */
/*
* same fsm state for ccp, too???
*/
lns[linkunit].ccp_unit = lns[i].ccp_unit;
lns[linkunit].ipxcp_unit = lns[i].ipxcp_unit;
lns[linkunit].phase = PHASE_NETWORK;
/*
* bundle the links on driver layer
*/
syslog(LOG_INFO,"bundle: %d",
sifbundle(linkunit,i)); /* sets MP Flags */
break;
}
}
}
}
if(higher_up) /* no bundle -> kick higher layers */
{
if(go->neg_mp && ho->neg_mp)
enable_mp(linkunit,0x0);
if(ipcp_protent.enabled_flag) {
int ipcp_unit = lns[linkunit].ipcp_unit = ipcp_getunit(linkunit);
if(ipcp_unit >= 0) {
if(useifip)
setifip(lns[linkunit].ipcp_unit);
if(usefirstip && lns[linkunit].addresses) {
ipcp_options *wo = &ipcp_wantoptions[ipcp_unit];
struct hostent *hp = gethostbyname(lns[linkunit].addresses->word);
if (hp != NULL && hp->h_addrtype == AF_INET) {
wo->hisaddr = *(u_int32_t *)hp->h_addr;
}
}
(*ipcp_protent.lowerup)(lns[linkunit].ipcp_unit);
(*ipcp_protent.open)(lns[linkunit].ipcp_unit);
}
}
if(ipxcp_protent.enabled_flag) {
lns[linkunit].ipxcp_unit = ipxcp_getunit(linkunit);
(*ipxcp_protent.lowerup)(lns[linkunit].ipxcp_unit);
(*ipxcp_protent.open)(lns[linkunit].ipxcp_unit);
}
if(ccp_link_protent.enabled_flag) {
syslog(LOG_NOTICE,"linkCCP enabled! Trying CCP.\n");
lns[linkunit].ccp_unit = ccp_getunit(linkunit,PPP_LINK_CCP);
(*ccp_link_protent.lowerup)(lns[linkunit].ccp_unit);
(*ccp_link_protent.open)(lns[linkunit].ccp_unit);
}
if(ccp_protent.enabled_flag) {
syslog(LOG_NOTICE,"CCP enabled! Trying CCP.\n");
lns[linkunit].ccp_unit = ccp_getunit(linkunit,PPP_CCP);
(*ccp_protent.lowerup)(lns[linkunit].ccp_unit);
(*ccp_protent.open)(lns[linkunit].ccp_unit);
}
lns[linkunit].phase = PHASE_NETWORK;
}
if(ccp_link_protent.enabled_flag) {
syslog(LOG_NOTICE,"linkCCP enabled! Trying CCP.\n");
lns[linkunit].ccp_l_unit = ccp_getunit(linkunit,PPP_LINK_CCP);
(*ccp_link_protent.lowerup)(lns[linkunit].ccp_l_unit);
(*ccp_link_protent.open)(lns[linkunit].ccp_l_unit);
}
}
/*
* Proceed to the callback phase which may be empty.
*/
static void callback_phase(int linkunit)
{
lcp_options *go = &lcp_gotoptions[ lns[linkunit].lcp_unit ];
/* hack here: remote is always the server for callback */
if (go->neg_callback && !(lns[linkunit].pci.calltype & CALLTYPE_INCOMING)) {
/* Do CBCP if we did negotiate CBCP, take the lionk
down and wait for callback if we negotiated RFC
1570 style callback */
if (go->cbopt.type == CB_CBCP) {
lns[linkunit].phase = PHASE_CALLBACK;
/* cbcp always corresponds to a link */
lns[linkunit].cbcp_unit = linkunit;
cbcp[ lns[linkunit].cbcp_unit ].us_unit = linkunit;
(*cbcp_protent.lowerup)(lns[linkunit].cbcp_unit);
(*cbcp_protent.open)(lns[linkunit].cbcp_unit);
} else {
lns[linkunit].phase = PHASE_TERMINATE;
}
} else {
network_phase(linkunit);
}
}
/*
* The peer has failed to authenticate himself using `protocol'.
*/
void auth_peer_fail(int unit,int protocol, int reason)
{
/*
* Authentication failure: take the link down
*/
lcp_close(lns[unit].lcp_unit,"auth failure");
lns[unit].phase = PHASE_TERMINATE;
auth_script(unit, _PATH_AUTHFAIL, reason);
}
/*
* The peer has been successfully authenticated using `protocol'.
*/
void auth_peer_success(int linkunit,int 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. (via callback phase)
*/
if ((lns[linkunit].auth_pending &= ~bit) == 0 &&
lns[linkunit].phase == PHASE_AUTHENTICATE) {
callback_phase(linkunit);
}
}
/*
* We have failed to authenticate ourselves to the peer using `protocol'.
*/
void auth_withpeer_fail(int unit,int protocol,int reason)
{
/*
* 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.
*/
auth_script(unit, _PATH_AUTHFAIL, reason);
}
/*
* We have successfully authenticated ourselves with the peer using `protocol'.
*/
void auth_withpeer_success(int linkunit,int 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 ((lns[linkunit].auth_pending &= ~bit) == 0 &&
lns[linkunit].phase == PHASE_AUTHENTICATE)
callback_phase(linkunit);
}
/*
* check_auth_options - called to check authentication options.
*/
void check_auth_options()
{
int i;
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.
*/
#ifdef RADIUS
if (ao->neg_upap && passwd[0] == 0 && !get_upap_passwd()
&& !useradius ) {
#else
if (ao->neg_upap && passwd[0] == 0 && !get_upap_passwd()) {
#endif
syslog(LOG_INFO,"info: no PAP secret entry for this user!\n");
ao->neg_upap = 0;
}
#ifdef RADIUS
if (wo->neg_upap && !uselogin && !have_upap_secret()
&& !useradius )
#else
if (wo->neg_upap && !uselogin && !have_upap_secret())
#endif
wo->neg_upap = 0;
#ifdef RADIUS
if (ao->neg_chap && !have_chap_secret(our_name, remote_name)
&& !useradius ) {
#else
if (ao->neg_chap && !have_chap_secret(our_name, remote_name)) {
#endif
syslog(LOG_INFO,"info: no CHAP secret entry for this user!\n");
ao->neg_chap = 0;
}
#ifdef RADIUS
if (wo->neg_chap && !have_chap_secret(remote_name, our_name)
&& !useradius )
#else
if (wo->neg_chap && !have_chap_secret(remote_name, our_name))
#endif
wo->neg_chap = 0;
if (auth_required && !wo->neg_chap && !wo->neg_upap) {
fprintf(stderr,"ipppd: peer authentication required but no authentication files accessible\n or user %s not found in auth files",user);
exit(1);
}
for(i=1;i<NUM_PPP;i++) /* duplicate options */
{
lcp_wantoptions[i].neg_upap = lcp_wantoptions[0].neg_upap;
lcp_wantoptions[i].neg_chap = lcp_wantoptions[0].neg_chap;
lcp_allowoptions[i].neg_upap = lcp_allowoptions[0].neg_upap;
lcp_allowoptions[i].neg_chap = lcp_allowoptions[0].neg_chap;
}
}
/*
* reload PW
*/
void auth_reload_upap_pw(void)
{
if(lcp_allowoptions[0].neg_upap)
get_upap_passwd();
}
/*
* 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 linkunit,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];
/*
* Make copies of apasswd and auser, then null-terminate them.
*/
BCOPY(apasswd, passwd, passwdlen);
passwd[passwdlen] = '\0';
BCOPY(auser, user, userlen);
user[userlen] = '\0';
syslog(LOG_INFO,"Check_passwd called with user=%s\n",user);
strcpy(lns[linkunit].peer_authname,user);
/*
* 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 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 && (cryptpap || strcmp(passwd, secret) != 0)
&& strcmp(crypt(passwd, secret), secret) != 0)) {
syslog(LOG_WARNING, "PAP authentication failure for %s", user);
ret = UPAP_AUTHNAK;
}
fclose(f);
}
if (uselogin && ret == UPAP_AUTHACK) {
ret = check_login(user, passwd, msg, msglen,linkunit);
if (ret == UPAP_AUTHNAK) {
syslog(LOG_WARNING, "PAP login failure for %s", user);
}
else
lns[linkunit].logged_in = TRUE;
}
if (ret == UPAP_AUTHNAK) {
*msg = "Login incorrect";
*msglen = strlen(*msg);
if (lns[linkunit].attempts++ >= 10) {
syslog(LOG_WARNING, "%d LOGIN FAILURES ON %s, %s",
lns[linkunit].attempts, lns[linkunit].devnam, user);
lcp_close(lns[linkunit].lcp_unit,"max auth exceed");
lns[linkunit].phase = PHASE_TERMINATE;
}
#if 0
if (attempts > 3)
sleep((u_int) (attempts - 3) * 5);
#endif
if (addrs != NULL)
free_wordlist(addrs);
} else {
lns[linkunit].attempts = 0; /* Reset count */
*msg = "Login ok";
*msglen = strlen(*msg);
if (lns[linkunit].addresses != NULL)
free_wordlist(lns[linkunit].addresses);
lns[linkunit].addresses = addrs;
auth_script(linkunit,_PATH_AUTHUP,0);
lns[linkunit].auth_up_script = 1;
}
return ret;
}
#ifdef RADIUS
/*
* Name: radius_check_passwd
*
* Purpose: Check the user name and passwd against RADIUS server
* and acording to configuration also perform standard check_passwd
*
* returns:
* UPAP_AUTHNAK: Authentication failed.
* UPAP_AUTHACK: Authentication succeeded.
* In either case, msg points to an appropriate message.
*/
int radius_check_passwd(linkunit,auser,userlen,apasswd,passwdlen,msg,msglen)
int linkunit ;
char *auser ;
int userlen ;
char *apasswd ;
int passwdlen ;
char **msg ;
int *msglen ;
{
int ret;
char passwd[256], user[256];
/*
* Make copies of apasswd and auser, then null-terminate them.
*/
BCOPY(apasswd, passwd, passwdlen);
passwd[passwdlen] = '\0';
BCOPY(auser, user, userlen);
user[userlen] = '\0';
strcpy(lns[linkunit].peer_authname,user);
ret = UPAP_AUTHACK;
if ( useradius )
{
if ( auth_order & AUTH_RADIUS_FST )
{
ret = radius_pap_auth( linkunit, user, passwd, msg, msglen );
if ((ret == UPAP_AUTHNAK) && (auth_order & AUTH_LOCAL_SND))
{
ret = check_passwd (linkunit,auser,userlen,apasswd,passwdlen,msg,msglen) ;
}
}
else if ( auth_order & AUTH_LOCAL_FST )
{
ret = check_passwd (linkunit,auser,userlen,apasswd,passwdlen,msg,msglen) ;
if ((auth_order & AUTH_RADIUS_SND) && (ret == UPAP_AUTHNAK))
{
ret = radius_pap_auth( linkunit, user, passwd, msg, msglen );
}
}
}
else
{
ret = check_passwd (linkunit,auser,userlen,apasswd,passwdlen,msg,msglen) ;
}
if (ret == UPAP_AUTHNAK)
{
*msg = "Login incorrect";
*msglen = strlen(*msg);
if (lns[linkunit].attempts++ >= 10)
{
syslog(LOG_WARNING, "%d LOGIN FAILURES ON %s, %s",
lns[linkunit].attempts,
lns[linkunit].devnam, user);
lcp_close(lns[linkunit].lcp_unit,
"max auth exceed");
lns[linkunit].phase = PHASE_TERMINATE;
/* should I die here it must be something wrong here then */
/* then outside script can reestablish ipppd */
}
}
else
{
lns[linkunit].attempts = 0; /* Reset count */
*msg = "Login ok";
*msglen = strlen(*msg);
}
return ret;
}
#endif
/*
* check_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 check_login(char *user,char *passwd,char **msg,int *msglen,int unit)
{
struct passwd *pw;
char *epasswd;
char *tty;
#ifdef HAVE_SHADOW_H
struct spwd *spwd;
extern int isexpired (struct passwd *, struct spwd *);
#endif
if ((pw = getpwnam(user)) == NULL) {
return (UPAP_AUTHNAK);
}
#ifdef HAVE_SHADOW_H
/* try to deal with shadow */
spwd = getspnam(user);
if (spwd) {
/* check the age of the password entry */
if (isexpired(pw, spwd)) {
syslog(LOG_WARNING,"Expired password for %s",user);
return (UPAP_AUTHNAK);
}
pw->pw_passwd = spwd->sp_pwdp;
}
endspent();
#endif
/*
* XXX If no passwd, let them login without one.
*/
if (!pw->pw_passwd || *pw->pw_passwd == '\0') {
return (UPAP_AUTHACK);
}
epasswd = crypt(passwd, pw->pw_passwd);
if (strcmp(epasswd, pw->pw_passwd)) {
return (UPAP_AUTHNAK);
}
syslog(LOG_INFO, "user %s logged in", user);
/*
* Write a wtmp entry for this user.
*/
tty = lns[unit].devnam;
if (strncmp(tty, "/dev/", 5) == 0)
tty += 5;
logwtmputmp(unit, tty, user, ""); /* Add wtmp login entry */
return (UPAP_AUTHACK);
}
/*
* logout - Logout the user.
*/
static void do_logout(int unit)
{
char *tty;
tty = lns[unit].devnam;
if (strncmp(tty, "/dev/", 5) == 0)
tty += 5;
logwtmputmp(unit, tty, "", ""); /* Wipe out wtmp logout entry */
}
/*
* 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)
{
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 (lns[unit].addresses != NULL)
free_wordlist(lns[unit].addresses);
lns[unit].addresses = 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(void)
{
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(void)
{
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(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 (lns[unit].addresses != NULL)
free_wordlist(lns[unit].addresses);
lns[unit].addresses = 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(int unit,u_int32_t addr)
{
u_int32_t a;
int accept;
u_int32_t mask;
u_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 = lns[unit].addresses) == NULL)
return 1; /* no restriction */
for (; addrs != NULL; addrs = addrs->next) {
/* "-" means no addresses authorized */
ptr_word = addrs->word;
if (strcmp(ptr_word, "-") == 0)
break;
/* "*" means any addresses authorized */
if (strcmp(ptr_word, "*") == 0)
return 1;
accept = 1;
if (*ptr_word == '!') {
accept = 0;
++ptr_word;
}
ptr_mask = strchr (ptr_word, '/');
if (ptr_mask == NULL)
mask = 0xFFFFFFFFUL;
else {
int bit_count;
*ptr_mask = '\0';
bit_count = (int) strtol (ptr_mask, (char **) 0, 10);
if (bit_count <= 0 || bit_count > 32) {
syslog (LOG_WARNING,
"invalid address length %s in auth. address list",
ptr_mask);
*ptr_mask = '/';
continue;
}
mask = ~((1UL << (32 - bit_count)) - 1UL);
}
hp = gethostbyname(ptr_word);
if (hp != NULL && hp->h_addrtype == AF_INET) {
a = *(u_int32_t *)hp->h_addr;
mask = -1L;
} 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)
*ptr_mask = '/';
if (a == (u_int32_t)-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(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(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(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(struct wordlist *wp)
{
struct wordlist *next;
while (wp != NULL) {
next = wp->next;
free(wp);
wp = next;
}
}
/*
* auth_script - execute a script with arguments
* interface-name peer-name real-user tty speed remote-number [fail-reason]
*/
static void auth_script(int linkunit,char *script,int error_reason)
{
char strspeed[32];
struct passwd *pw;
char struid[32];
char *user_name;
char *argv[9];
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", 64000);
argv[0] = script;
argv[1] = lns[linkunit].ifname;
argv[2] = lns[linkunit].peer_authname;
argv[3] = user_name;
argv[4] = lns[linkunit].devnam;
argv[5] = strspeed;
argv[6] = lns[linkunit].pci.remote_num;
argv[7] = NULL;
if (error_reason) {
sprintf(struid,"%d",error_reason);
argv[7] = struid;
argv[8] = NULL;
}
run_program(script, argv, debug,linkunit);
}
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