shadow/src/login.c

1310 lines
32 KiB
C

/*
* Copyright 1989 - 1994, Julianne Frances Haugh
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of Julianne F. Haugh nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY JULIE HAUGH AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL JULIE HAUGH OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include <config.h>
#include "rcsid.h"
RCSID (PKG_VER "$Id: login.c,v 1.38 2005/01/17 23:12:04 kloczek Exp $")
#include "prototypes.h"
#include "defines.h"
#include <sys/stat.h>
#include <stdio.h>
#include <errno.h>
#include <pwd.h>
#include <grp.h>
#include <signal.h>
#if HAVE_LASTLOG_H
#include <lastlog.h>
#else
#include "lastlog_.h"
#endif
#include "faillog.h"
#include "failure.h"
#include "pwauth.h"
#include "getdef.h"
#ifdef RADIUS
/*
* Support for RADIUS authentication based on a hacked util-linux login
* source sent to me by Jon Lewis. Not tested. You need to link login
* with the radauth.c file (not included here - it doesn't have a clear
* copyright statement, and I don't want to have problems with Debian
* putting the whole package in non-free because of this). --marekm
*/
#include "radlogin.h"
#endif
#ifdef UT_ADDR
#include <netdb.h>
#endif
#ifdef USE_PAM
#include "pam_defs.h"
static const struct pam_conv conv = {
misc_conv,
NULL
};
static pam_handle_t *pamh = NULL;
#define PAM_FAIL_CHECK if (retcode != PAM_SUCCESS) { \
fprintf(stderr,"\n%s\n",pam_strerror(pamh, retcode)); \
syslog(LOG_ERR,"%s",pam_strerror(pamh, retcode)); \
pam_end(pamh, retcode); exit(1); \
}
#define PAM_END { retcode = pam_close_session(pamh,0); \
pam_end(pamh,retcode); }
#endif /* USE_PAM */
/*
* Needed for MkLinux DR1/2/2.1 - J.
*/
#ifndef LASTLOG_FILE
#define LASTLOG_FILE "/var/log/lastlog"
#endif
const char *hostname = "";
static struct passwd pwent;
#if HAVE_UTMPX_H
extern struct utmpx utxent;
struct utmpx failent;
#else
struct utmp failent;
#endif
extern struct utmp utent;
struct lastlog lastlog;
static int pflg = 0;
static int fflg = 0;
#ifdef RLOGIN
static int rflg = 0;
#else
#define rflg 0
#endif
static int hflg = 0;
static int preauth_flag = 0;
/*
* Global variables.
*/
static char *Prog;
static int amroot;
static int timeout;
/*
* External identifiers.
*/
extern char **newenvp;
extern size_t newenvc;
extern void dolastlog (struct lastlog *, const struct passwd *,
const char *, const char *);
extern char **environ;
#ifndef USE_PAM
extern int login_access (const char *, const char *);
#endif
extern void login_fbtab (const char *, uid_t, gid_t);
#ifndef ALARM
#define ALARM 60
#endif
#ifndef RETRIES
#define RETRIES 3
#endif
#ifndef USE_PAM
static struct faillog faillog;
#endif
/* local function prototypes */
static void usage (void);
static void setup_tty (void);
static void check_flags (int, char *const *);
#ifndef USE_PAM
static void bad_time_notify (void);
static void check_nologin (void);
#endif
static void init_env (void);
static RETSIGTYPE alarm_handler (int);
/*
* usage - print login command usage and exit
*
* login [ name ]
* login -r hostname (for rlogind)
* login -h hostname (for telnetd, etc.)
* login -f name (for pre-authenticated login: datakit, xterm, etc.)
*/
static void usage (void)
{
fprintf (stderr, _("Usage: %s [-p] [name]\n"), Prog);
if (!amroot)
exit (1);
fprintf (stderr, _(" %s [-p] [-h host] [-f name]\n"), Prog);
#ifdef RLOGIN
fprintf (stderr, _(" %s [-p] -r host\n"), Prog);
#endif
exit (1);
}
static void setup_tty (void)
{
TERMIO termio;
GTTY (0, &termio); /* get terminal characteristics */
/*
* Add your favorite terminal modes here ...
*/
termio.c_lflag |= ISIG | ICANON | ECHO | ECHOE;
termio.c_iflag |= ICRNL;
#if defined(ECHOKE) && defined(ECHOCTL)
termio.c_lflag |= ECHOKE | ECHOCTL;
#endif
#if defined(ECHOPRT) && defined(NOFLSH) && defined(TOSTOP)
termio.c_lflag &= ~(ECHOPRT | NOFLSH | TOSTOP);
#endif
#ifdef ONLCR
termio.c_oflag |= ONLCR;
#endif
#ifdef SUN4
/*
* Terminal setup for SunOS 4.1 courtesy of Steve Allen
* at UCO/Lick.
*/
termio.c_cc[VEOF] = '\04';
termio.c_cflag &= ~CSIZE;
termio.c_cflag |= (PARENB | CS7);
termio.c_lflag |= (ISIG | ICANON | ECHO | IEXTEN);
termio.c_iflag |=
(BRKINT | IGNPAR | ISTRIP | IMAXBEL | ICRNL | IXON);
termio.c_iflag &= ~IXANY;
termio.c_oflag |= (XTABS | OPOST | ONLCR);
#endif
/* leave these values unchanged if not specified in login.defs */
termio.c_cc[VERASE] =
getdef_num ("ERASECHAR", termio.c_cc[VERASE]);
termio.c_cc[VKILL] = getdef_num ("KILLCHAR", termio.c_cc[VKILL]);
/*
* ttymon invocation prefers this, but these settings won't come into
* effect after the first username login
*/
STTY (0, &termio);
}
/*
* Tell the user that this is not the right time to login at this tty
*/
#ifndef USE_PAM
static void bad_time_notify (void)
{
#ifdef HUP_MESG_FILE
FILE *mfp;
if ((mfp = fopen (HUP_MESG_FILE, "r")) != NULL) {
int c;
while ((c = fgetc (mfp)) != EOF) {
if (c == '\n')
putchar ('\r');
putchar (c);
}
fclose (mfp);
} else
#endif
printf (_("Invalid login time\n"));
fflush (stdout);
}
#endif
static void check_flags (int argc, char *const *argv)
{
int arg;
/*
* Check the flags for proper form. Every argument starting with
* "-" must be exactly two characters long. This closes all the
* clever rlogin, telnet, and getty holes.
*/
for (arg = 1; arg < argc; arg++) {
if (argv[arg][0] == '-' && strlen (argv[arg]) > 2)
usage ();
}
}
#ifndef USE_PAM
static void check_nologin (void)
{
char *fname;
/*
* Check to see if system is turned off for non-root users.
* This would be useful to prevent users from logging in
* during system maintenance. We make sure the message comes
* out for root so she knows to remove the file if she's
* forgotten about it ...
*/
fname = getdef_str ("NOLOGINS_FILE");
if (fname != NULL && access (fname, F_OK) == 0) {
FILE *nlfp;
int c;
/*
* Cat the file if it can be opened, otherwise just
* print a default message
*/
if ((nlfp = fopen (fname, "r"))) {
while ((c = getc (nlfp)) != EOF) {
if (c == '\n')
putchar ('\r');
putchar (c);
}
fflush (stdout);
fclose (nlfp);
} else
printf (_
("\nSystem closed for routine maintenance\n"));
/*
* Non-root users must exit. Root gets the message, but
* gets to login.
*/
if (pwent.pw_uid != 0) {
closelog ();
exit (0);
}
printf (_
("\n[Disconnect bypassed -- root login allowed.]\n"));
}
}
#endif /* !USE_PAM */
static void init_env (void)
{
char *cp, *tmp;
if ((tmp = getenv ("LANG"))) {
addenv ("LANG", tmp);
}
/*
* Add the timezone environmental variable so that time functions
* work correctly.
*/
if ((tmp = getenv ("TZ"))) {
addenv ("TZ", tmp);
} else if ((cp = getdef_str ("ENV_TZ")))
addenv (*cp == '/' ? tz (cp) : cp, NULL);
/*
* Add the clock frequency so that profiling commands work
* correctly.
*/
if ((tmp = getenv ("HZ"))) {
addenv ("HZ", tmp);
} else if ((cp = getdef_str ("ENV_HZ")))
addenv (cp, NULL);
}
static RETSIGTYPE alarm_handler (int sig)
{
fprintf (stderr, _("\nLogin timed out after %d seconds.\n"),
timeout);
exit (0);
}
/*
* login - create a new login session for a user
*
* login is typically called by getty as the second step of a
* new user session. getty is responsible for setting the line
* characteristics to a reasonable set of values and getting
* the name of the user to be logged in. login may also be
* called to create a new user session on a pty for a variety
* of reasons, such as X servers or network logins.
*
* the flags which login supports are
*
* -p - preserve the environment
* -r - perform autologin protocol for rlogin
* -f - do not perform authentication, user is preauthenticated
* -h - the name of the remote host
*/
int main (int argc, char **argv)
{
char username[32];
char tty[BUFSIZ];
#ifdef RLOGIN
char term[128] = "";
#endif
#if defined(HAVE_STRFTIME) && !defined(USE_PAM)
char ptime[80];
#endif
int reason = PW_LOGIN;
int delay;
int retries;
int failed;
int flag;
int subroot = 0;
int is_console;
const char *cp;
char *tmp;
char fromhost[512];
struct passwd *pwd;
char **envp = environ;
static char temp_pw[2];
static char temp_shell[] = "/bin/sh";
#ifdef USE_PAM
int retcode;
pid_t child;
char *pam_user;
#endif /* USE_PAM */
#if defined(SHADOWPWD) && !defined(USE_PAM)
struct spwd *spwd = NULL;
#endif
#ifdef RADIUS
RAD_USER_DATA rad_user_data;
int is_rad_login;
#endif
#if defined(RADIUS) || defined(DES_RPC) || defined(KERBEROS)
/* from pwauth.c */
extern char *clear_pass;
extern int wipe_clear_pass;
/*
* We may need the password later, don't want pw_auth() to wipe it
* (we do it ourselves when it is no longer needed). --marekm
*/
wipe_clear_pass = 0;
#endif
/*
* Some quick initialization.
*/
sanitize_env ();
setlocale (LC_ALL, "");
bindtextdomain (PACKAGE, LOCALEDIR);
textdomain (PACKAGE);
initenv ();
username[0] = '\0';
amroot = (getuid () == 0);
Prog = Basename (argv[0]);
check_flags (argc, argv);
while ((flag = getopt (argc, argv, "d:f:h:pr:")) != EOF) {
switch (flag) {
case 'p':
pflg++;
break;
case 'f':
/*
* username must be a separate token
* (-f root, *not* -froot). --marekm
*/
if (optarg != argv[optind - 1])
usage ();
fflg++;
STRFCPY (username, optarg);
break;
#ifdef RLOGIN
case 'r':
rflg++;
hostname = optarg;
reason = PW_RLOGIN;
break;
#endif
case 'h':
hflg++;
hostname = optarg;
reason = PW_TELNET;
break;
case 'd':
/* "-d device" ignored for compatibility */
break;
default:
usage ();
}
}
#ifdef RLOGIN
/*
* Neither -h nor -f should be combined with -r.
*/
if (rflg && (hflg || fflg))
usage ();
#endif
/*
* Allow authentication bypass only if real UID is zero.
*/
if ((rflg || fflg || hflg) && !amroot) {
fprintf (stderr, _("%s: permission denied.\n"), Prog);
exit (1);
}
if (!isatty (0) || !isatty (1) || !isatty (2))
exit (1); /* must be a terminal */
#if 0
/*
* Get the utmp file entry and get the tty name from it. The
* current process ID must match the process ID in the utmp
* file if there are no additional flags on the command line.
*/
checkutmp (!rflg && !fflg && !hflg);
#else
/*
* Be picky if run by normal users (possible if installed setuid
* root), but not if run by root. This way it still allows logins
* even if your getty is broken, or if something corrupts utmp,
* but users must "exec login" which will use the existing utmp
* entry (will not overwrite remote hostname). --marekm
*/
checkutmp (!amroot);
#endif
STRFCPY (tty, utent.ut_line);
is_console = console (tty);
if (rflg || hflg) {
#ifdef UT_ADDR
struct hostent *he;
/*
* Fill in the ut_addr field (remote login IP address). XXX
* - login from util-linux does it, but this is not the
* right place to do it. The program that starts login
* (telnetd, rlogind) knows the IP address, so it should
* create the utmp entry and fill in ut_addr.
* gethostbyname() is not 100% reliable (the remote host may
* be unknown, etc.). --marekm
*/
if ((he = gethostbyname (hostname))) {
utent.ut_addr =
*((int32_t *) (he->h_addr_list[0]));
#endif
#ifdef UT_HOST
strncpy (utent.ut_host, hostname,
sizeof (utent.ut_host));
#endif
#if HAVE_UTMPX_H
strncpy (utxent.ut_host, hostname,
sizeof (utxent.ut_host));
#endif
/*
* Add remote hostname to the environment. I think
* (not sure) I saw it once on Irix. --marekm
*/
addenv ("REMOTEHOST", hostname);
}
#ifdef __linux__
/*
* workaround for init/getty leaving junk in ut_host at least in
* some version of RedHat. --marekm
*/
else if (amroot)
memzero (utent.ut_host, sizeof utent.ut_host);
#endif
if (fflg)
preauth_flag++;
if (hflg)
reason = PW_RLOGIN;
#ifdef RLOGIN
if (rflg
&& do_rlogin (hostname, username, sizeof username,
term, sizeof term))
preauth_flag++;
#endif
OPENLOG ("login");
setup_tty ();
umask (getdef_num ("UMASK", 077));
{
/*
* Use the ULIMIT in the login.defs file, and if
* there isn't one, use the default value. The
* user may have one for themselves, but otherwise,
* just take what you get.
*/
long limit = getdef_long ("ULIMIT", -1L);
if (limit != -1)
set_filesize_limit (limit);
}
/*
* The entire environment will be preserved if the -p flag
* is used.
*/
if (pflg)
while (*envp) /* add inherited environment, */
addenv (*envp++, NULL); /* some variables change later */
#ifdef RLOGIN
if (term[0] != '\0')
addenv ("TERM", term);
else
#endif
/* preserve TERM from getty */
if (!pflg && (tmp = getenv ("TERM")))
addenv ("TERM", tmp);
init_env ();
if (optind < argc) { /* get the user name */
if (rflg || fflg)
usage ();
STRFCPY (username, argv[optind]);
strzero (argv[optind]);
++optind;
}
if (optind < argc) /* now set command line variables */
set_env (argc - optind, &argv[optind]);
if (rflg || hflg)
cp = hostname;
else
#ifdef UT_HOST
if (utent.ut_host[0])
cp = utent.ut_host;
else
#endif
#if HAVE_UTMPX_H
if (utxent.ut_host[0])
cp = utxent.ut_host;
else
#endif
cp = "";
if (*cp)
snprintf (fromhost, sizeof fromhost,
_(" on `%.100s' from `%.200s'"), tty,
cp);
else
snprintf (fromhost, sizeof fromhost,
_(" on `%.100s'"), tty);
top:
/* only allow ALARM sec. for login */
signal (SIGALRM, alarm_handler);
timeout = getdef_num ("LOGIN_TIMEOUT", ALARM);
if (timeout > 0)
alarm (timeout);
environ = newenvp; /* make new environment active */
delay = getdef_num ("FAIL_DELAY", 1);
retries = getdef_num ("LOGIN_RETRIES", RETRIES);
#ifdef USE_PAM
retcode = pam_start ("login", username, &conv, &pamh);
if (retcode != PAM_SUCCESS) {
fprintf (stderr,
"login: PAM Failure, aborting: %s\n",
pam_strerror (pamh, retcode));
syslog (LOG_ERR, "Couldn't initialize PAM: %s",
pam_strerror (pamh, retcode));
exit (99);
}
/*
* hostname & tty are either set to NULL or their correct values,
* depending on how much we know. We also set PAM's fail delay to
* ours.
*/
retcode = pam_set_item (pamh, PAM_RHOST, hostname);
PAM_FAIL_CHECK;
retcode = pam_set_item (pamh, PAM_TTY, tty);
PAM_FAIL_CHECK;
#ifdef HAVE_PAM_FAIL_DELAY
retcode = pam_fail_delay (pamh, 1000000 * delay);
PAM_FAIL_CHECK;
#endif
/* if fflg == 1, then the user has already been authenticated */
if (!fflg || (getuid () != 0)) {
int failcount = 0;
char hostn[256];
char login_prompt[256]; /* That's one hell of a prompt :) */
/* Make the login prompt look like we want it */
if (!gethostname (hostn, sizeof (hostn)))
snprintf (login_prompt,
sizeof (login_prompt),
"%s login: ", hostn);
else
snprintf (login_prompt,
sizeof (login_prompt),
"login: ");
retcode =
pam_set_item (pamh, PAM_USER_PROMPT,
login_prompt);
PAM_FAIL_CHECK;
/* if we didn't get a user on the command line,
set it to NULL */
pam_get_item (pamh, PAM_USER,
(const void **) &pam_user);
if (pam_user[0] == '\0')
pam_set_item (pamh, PAM_USER, NULL);
/*
* There may be better ways to deal with some of
* these conditions, but at least this way I don't
* think we'll be giving away information. Perhaps
* someday we can trust that all PAM modules will
* pay attention to failure count and get rid of
* MAX_LOGIN_TRIES?
*/
retcode = pam_authenticate (pamh, 0);
while ((failcount++ < retries) &&
((retcode == PAM_AUTH_ERR) ||
(retcode == PAM_USER_UNKNOWN) ||
(retcode == PAM_CRED_INSUFFICIENT) ||
(retcode == PAM_AUTHINFO_UNAVAIL))) {
pam_get_item (pamh, PAM_USER,
(const void **) &pam_user);
syslog (LOG_NOTICE,
"FAILED LOGIN %d FROM %s FOR %s, %s",
failcount, hostname, pam_user,
pam_strerror (pamh, retcode));
#ifdef HAVE_PAM_FAIL_DELAY
pam_fail_delay (pamh, 1000000 * delay);
#endif
fprintf (stderr, "Login incorrect\n\n");
pam_set_item (pamh, PAM_USER, NULL);
retcode = pam_authenticate (pamh, 0);
}
if (retcode != PAM_SUCCESS) {
pam_get_item (pamh, PAM_USER,
(const void **) &pam_user);
if (retcode == PAM_MAXTRIES)
syslog (LOG_NOTICE,
"TOO MANY LOGIN TRIES (%d) FROM %s FOR %s, %s",
failcount, hostname,
pam_user,
pam_strerror (pamh,
retcode));
else
syslog (LOG_NOTICE,
"FAILED LOGIN SESSION FROM %s FOR %s, %s",
hostname, pam_user,
pam_strerror (pamh,
retcode));
fprintf (stderr, "\nLogin incorrect\n");
pam_end (pamh, retcode);
exit (0);
}
retcode = pam_acct_mgmt (pamh, 0);
if (retcode == PAM_NEW_AUTHTOK_REQD) {
retcode =
pam_chauthtok (pamh,
PAM_CHANGE_EXPIRED_AUTHTOK);
}
PAM_FAIL_CHECK;
}
/* Grab the user information out of the password file for future usage
First get the username that we are actually using, though.
*/
retcode =
pam_get_item (pamh, PAM_USER,
(const void **) &pam_user);
setpwent ();
pwd = getpwnam (pam_user);
if (fflg) {
retcode = pam_acct_mgmt(pamh, 0);
PAM_FAIL_CHECK;
}
if (!pwd || setup_groups (pwd))
exit (1);
retcode = pam_setcred (pamh, PAM_ESTABLISH_CRED);
PAM_FAIL_CHECK;
retcode = pam_open_session (pamh, 0);
PAM_FAIL_CHECK;
#else /* ! USE_PAM */
while (1) { /* repeatedly get login/password pairs */
failed = 0; /* haven't failed authentication yet */
#ifdef RADIUS
is_rad_login = 0;
#endif
if (!username[0]) { /* need to get a login id */
if (subroot) {
closelog ();
exit (1);
}
preauth_flag = 0;
#ifndef LOGIN_PROMPT
#ifdef __linux__ /* hostname login: - like in util-linux login */
login_prompt (_("\n%s login: "), username,
sizeof username);
#else
login_prompt (_("login: "), username,
sizeof username);
#endif
#else
login_prompt (LOGIN_PROMPT, username,
sizeof username);
#endif
continue;
}
#endif /* ! USE_PAM */
#ifdef USE_PAM
if (!(pwd = getpwnam (pam_user))) {
pwent.pw_name = pam_user;
#else
if (!(pwd = getpwnam (username))) {
pwent.pw_name = username;
#endif
strcpy (temp_pw, "!");
pwent.pw_passwd = temp_pw;
pwent.pw_shell = temp_shell;
preauth_flag = 0;
failed = 1;
} else {
pwent = *pwd;
}
#ifndef USE_PAM
#ifdef SHADOWPWD
spwd = NULL;
if (pwd
&& strcmp (pwd->pw_passwd,
SHADOW_PASSWD_STRING) == 0) {
spwd = getspnam (username);
if (spwd)
pwent.pw_passwd = spwd->sp_pwdp;
else
SYSLOG ((LOG_WARN,
"no shadow password for `%s'%s",
username, fromhost));
}
#endif /* SHADOWPWD */
/*
* If the encrypted password begins with a "!", the account
* is locked and the user cannot login, even if they have
* been "pre-authenticated."
*/
if (pwent.pw_passwd[0] == '!'
|| pwent.pw_passwd[0] == '*')
failed = 1;
/*
* The -r and -f flags provide a name which has already
* been authenticated by some server.
*/
if (preauth_flag)
goto auth_ok;
if (pw_auth
(pwent.pw_passwd, username, reason,
(char *) 0) == 0)
goto auth_ok;
#ifdef RADIUS
/*
* If normal passwd authentication didn't work, try radius.
*/
if (failed) {
pwd =
rad_authenticate (&rad_user_data,
username,
clear_pass ?
clear_pass : "");
if (pwd) {
is_rad_login = 1;
pwent = *pwd;
failed = 0;
goto auth_ok;
}
}
#endif /* RADIUS */
/*
* Don't log unknown usernames - I mistyped the password for
* username at least once. Should probably use LOG_AUTHPRIV
* for those who really want to log them. --marekm
*/
SYSLOG ((LOG_WARN, "invalid password for `%s' %s",
(pwd
|| getdef_bool ("LOG_UNKFAIL_ENAB")) ?
username : "UNKNOWN", fromhost));
failed = 1;
auth_ok:
/*
* This is the point where all authenticated users wind up.
* If you reach this far, your password has been
* authenticated and so on.
*/
#if defined(RADIUS) && !(defined(DES_RPC) || defined(KERBEROS))
if (clear_pass) {
strzero (clear_pass);
clear_pass = NULL;
}
#endif
if (!failed && pwent.pw_name && pwent.pw_uid == 0
&& !is_console) {
SYSLOG ((LOG_CRIT, "ILLEGAL ROOT LOGIN %s",
fromhost));
failed = 1;
}
#ifdef LOGIN_ACCESS
if (!failed
&& !login_access (username,
*hostname ? hostname : tty))
{
SYSLOG ((LOG_WARN, "LOGIN `%s' REFUSED %s", username,
fromhost));
failed = 1;
}
#endif
if (pwd && getdef_bool ("FAILLOG_ENAB") &&
!failcheck (pwent.pw_uid, &faillog, failed)) {
SYSLOG ((LOG_CRIT,
"exceeded failure limit for `%s' %s",
username, fromhost));
failed = 1;
}
if (!failed)
break;
/* don't log non-existent users */
if (pwd && getdef_bool ("FAILLOG_ENAB"))
failure (pwent.pw_uid, tty, &faillog);
if (getdef_str ("FTMP_FILE") != NULL) {
const char *failent_user;
#if HAVE_UTMPX_H
failent = utxent;
if (sizeof (failent.ut_tv) == sizeof (struct timeval))
gettimeofday ((struct timeval *) &failent.ut_tv, NULL);
else
{
struct timeval tv;
gettimeofday (&tv, NULL);
failent.ut_tv.tv_sec = tv.tv_sec;
failent.ut_tv.tv_usec = tv.tv_usec;
}
#else
failent = utent;
failent.ut_time = time (NULL);
#endif
if (pwd) {
failent_user = pwent.pw_name;
} else {
if (getdef_bool
("LOG_UNKFAIL_ENAB"))
failent_user = username;
else
failent_user = "UNKNOWN";
}
strncpy (failent.ut_user, failent_user,
sizeof (failent.ut_user));
#ifdef USER_PROCESS
failent.ut_type = USER_PROCESS;
#endif
failtmp (&failent);
}
memzero (username, sizeof username);
if (--retries <= 0)
SYSLOG ((LOG_CRIT, "REPEATED login failures%s",
fromhost));
#if 1
/*
* If this was a passwordless account and we get here, login
* was denied (securetty, faillog, etc.). There was no
* password prompt, so do it now (will always fail - the bad
* guys won't see that the passwordless account exists at
* all). --marekm
*/
if (pwent.pw_passwd[0] == '\0')
pw_auth ("!", username, reason,
(char *) 0);
#endif
/*
* Wait a while (a la SVR4 /usr/bin/login) before attempting
* to login the user again. If the earlier alarm occurs
* before the sleep() below completes, login will exit.
*/
if (delay > 0)
sleep (delay);
puts (_("Login incorrect"));
/* allow only one attempt with -r or -f */
if (rflg || fflg || retries <= 0) {
closelog ();
exit (1);
}
} /* while (1) */
#endif /* ! USE_PAM */
alarm (0); /* turn off alarm clock */
#ifndef USE_PAM /* PAM does this */
/*
* porttime checks moved here, after the user has been
* authenticated. now prints a message, as suggested
* by Ivan Nejgebauer <ian@unsux.ns.ac.yu>. --marekm
*/
if (getdef_bool ("PORTTIME_CHECKS_ENAB") &&
!isttytime (pwent.pw_name, tty, time ((time_t *) 0))) {
SYSLOG ((LOG_WARN, "invalid login time for `%s'%s",
username, fromhost));
closelog ();
bad_time_notify ();
exit (1);
}
check_nologin ();
#endif
if (getenv ("IFS")) /* don't export user IFS ... */
addenv ("IFS= \t\n", NULL); /* ... instead, set a safe IFS */
#ifdef USE_PAM
setutmp (pam_user, tty, hostname); /* make entry in utmp & wtmp files */
#else
setutmp (username, tty, hostname); /* make entry in utmp & wtmp files */
#endif
if (pwent.pw_shell[0] == '*') { /* subsystem root */
pwent.pw_shell++; /* skip the '*' */
subsystem (&pwent); /* figure out what to execute */
subroot++; /* say i was here again */
endpwent (); /* close all of the file which were */
endgrent (); /* open in the original rooted file */
#ifdef SHADOWPWD
endspent (); /* system. they will be re-opened */
#endif
#ifdef SHADOWGRP
endsgent (); /* in the new rooted file system */
#endif
goto top; /* go do all this all over again */
}
#ifndef USE_PAM /* pam_lastlog handles this */
if (getdef_bool ("LASTLOG_ENAB")) /* give last login and log this one */
dolastlog (&lastlog, &pwent, utent.ut_line,
hostname);
#endif
#ifndef USE_PAM /* PAM handles this as well */
/*
* Have to do this while we still have root privileges, otherwise we
* don't have access to /etc/shadow. expire() closes password files,
* and changes to the user in the child before executing the passwd
* program. --marekm
*/
#ifdef SHADOWPWD
if (spwd) { /* check for age of password */
if (expire (&pwent, spwd)) {
pwd = getpwnam (username);
spwd = getspnam (username);
if (pwd)
pwent = *pwd;
}
}
#endif /* SHADOWPWD */
#ifdef RADIUS
if (is_rad_login) {
char whofilename[128];
FILE *whofile;
snprintf (whofilename, sizeof whofilename,
"/var/log/radacct/%.20s", tty);
whofile = fopen (whofilename, "w");
if (whofile) {
fprintf (whofile, "%s\n", username);
fclose (whofile);
}
}
#endif
setup_limits (&pwent); /* nice, ulimit etc. */
#endif /* ! USE_PAM */
chown_tty (tty, &pwent);
#ifdef LOGIN_FBTAB
/*
* XXX - not supported yet. Change permissions and ownerships of
* devices like floppy/audio/mouse etc. for console logins, based
* on /etc/fbtab or /etc/logindevperm configuration files (Suns do
* this with their framebuffer devices). Problems:
*
* - most systems (except BSD) don't have that nice revoke() system
* call to ensure the previous user didn't leave a process holding
* one of these devices open or mmap'ed. Any volunteers to do it
* in Linux?
*
* - what to do with different users logged in on different virtual
* consoles? Maybe permissions should be changed only on user's
* request, by running a separate (setuid root) program?
*
* - init/telnetd/rlogind/whatever should restore permissions after
* the user logs out.
*
* Try the new CONSOLE_GROUPS feature instead. It adds specified
* groups (like "floppy") to the group set if the user is logged in
* on the console. This still has the first problem (users leaving
* processes with these devices open), but doesn't need to change
* any permissions, just make them 0660 root:floppy etc. --marekm
*
* Warning: users can still gain permanent access to these groups
* unless any user-writable filesystems are mounted with the
* "nosuid" option. Alternatively, the kernel could be modified to
* prevent ordinary users from setting the setgid bit on
* executables.
*/
login_fbtab (tty, pwent.pw_uid, pwent.pw_gid);
#endif
/* We call set_groups() above because this clobbers pam_groups.so */
#ifndef USE_PAM
if (setup_uid_gid (&pwent, is_console))
#else
if (change_uid (&pwent))
#endif
exit (1);
#ifdef KERBEROS
if (clear_pass)
login_kerberos (username, clear_pass);
#endif
#ifdef DES_RPC
if (clear_pass)
login_desrpc (clear_pass);
#endif
#if defined(DES_RPC) || defined(KERBEROS)
if (clear_pass)
strzero (clear_pass);
#endif
setup_env (&pwent); /* set env vars, cd to the home dir */
#ifdef USE_PAM
{
const char *const *env;
env = (const char *const *) pam_getenvlist (pamh);
while (env && *env) {
addenv (*env, NULL);
env++;
}
}
#endif
setlocale (LC_ALL, "");
bindtextdomain (PACKAGE, LOCALEDIR);
textdomain (PACKAGE);
if (!hushed (&pwent)) {
addenv ("HUSHLOGIN=FALSE", NULL);
/*
* pam_unix, pam_mail and pam_lastlog should take care of
* this
*/
#ifndef USE_PAM
motd (); /* print the message of the day */
if (getdef_bool ("FAILLOG_ENAB")
&& faillog.fail_cnt != 0) {
failprint (&faillog);
/* Reset the lockout times if logged in */
if (faillog.fail_max &&
faillog.fail_cnt >= faillog.fail_max) {
puts (_
("Warning: login re-enabled after temporary lockout.\n"));
SYSLOG ((LOG_WARN,
"login `%s' re-enabled after temporary lockout (%d failures)",
username,
(int) faillog.fail_cnt));
}
}
if (getdef_bool ("LASTLOG_ENAB")
&& lastlog.ll_time != 0) {
time_t ll_time = lastlog.ll_time;
#ifdef HAVE_STRFTIME
strftime (ptime, sizeof (ptime),
"%a %b %e %H:%M:%S %z %Y",
localtime (&ll_time));
printf (_("Last login: %s on %s"),
ptime, lastlog.ll_line);
#else
printf (_("Last login: %.19s on %s"),
ctime (&ll_time),
lastlog.ll_line);
#endif
#ifdef HAVE_LL_HOST /* __linux__ || SUN4 */
if (lastlog.ll_host[0])
printf (_(" from %.*s"),
(int) sizeof lastlog.
ll_host, lastlog.ll_host);
#endif
printf (".\n");
}
#ifdef SHADOWPWD
agecheck (&pwent, spwd);
#else
agecheck (&pwent);
#endif
mailcheck (); /* report on the status of mail */
#endif /* !USE_PAM */
} else
addenv ("HUSHLOGIN=TRUE", NULL);
if (getdef_str ("TTYTYPE_FILE") != NULL
&& getenv ("TERM") == NULL)
ttytype (tty);
signal (SIGQUIT, SIG_DFL); /* default quit signal */
signal (SIGTERM, SIG_DFL); /* default terminate signal */
signal (SIGALRM, SIG_DFL); /* default alarm signal */
signal (SIGHUP, SIG_DFL); /* added this. --marekm */
#ifdef USE_PAM
/*
* We must fork before setuid() because we need to call
* pam_close_session() as root.
*
* Note: not true in other (non-Linux) PAM implementations, where
* the parent process of login (init, telnetd, ...) is responsible
* for calling pam_close_session(). This avoids an extra process for
* each login. Maybe we should do this on Linux too? We let the
* admin configure whether they need to keep login around to close
* sessions.
*/
if (getdef_bool ("CLOSE_SESSIONS")) {
signal (SIGINT, SIG_IGN);
child = fork ();
if (child < 0) {
/* error in fork() */
fprintf (stderr,
"login: failure forking: %s",
strerror (errno));
PAM_END;
exit (0);
} else if (child) {
/*
* parent - wait for child to finish, then cleanup
* session
*/
wait (NULL);
PAM_END;
exit (0);
}
/* child */
}
#endif
signal (SIGINT, SIG_DFL); /* default interrupt signal */
endpwent (); /* stop access to password file */
endgrent (); /* stop access to group file */
#ifdef SHADOWPWD
endspent (); /* stop access to shadow passwd file */
#endif
#ifdef SHADOWGRP
endsgent (); /* stop access to shadow group file */
#endif
if (pwent.pw_uid == 0)
SYSLOG ((LOG_NOTICE, "ROOT LOGIN %s", fromhost));
else if (getdef_bool ("LOG_OK_LOGINS"))
SYSLOG ((LOG_INFO, "`%s' logged in %s", username, fromhost));
closelog ();
#ifdef RADIUS
if (is_rad_login) {
printf (_("Starting rad_login\n"));
rad_login (&rad_user_data);
exit (0);
}
#endif
if ((tmp = getdef_str ("FAKE_SHELL")) != NULL) {
shell (tmp, pwent.pw_shell); /* fake shell */
}
shell (pwent.pw_shell, (char *) 0); /* exec the shell finally. */
/* NOT REACHED */
return 0;
}