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path: root/login-utils/login.c
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/* This program is derived from 4.3 BSD software and is
   subject to the copyright notice below.

   The port to HP-UX has been motivated by the incapability
   of 'rlogin'/'rlogind' as per HP-UX 6.5 (and 7.0) to transfer window sizes.

   Changes:

   - General HP-UX portation. Use of facilities not available
     in HP-UX (e.g. setpriority) has been eliminated.
     Utmp/wtmp handling has been ported.

   - The program uses BSD command line options to be used
     in connection with e.g. 'rlogind' i.e. 'new login'.

   - HP features left out:          logging of bad login attempts in /etc/btmp,
				    they are sent to syslog

				    password expiry

				    '*' as login shell, add it if you need it

   - BSD features left out:         quota checks
				    password expiry
				    analysis of terminal type (tset feature)

   - BSD features thrown in:        Security logging to syslogd.
                                    This requires you to have a (ported) syslog
				    system -- 7.0 comes with syslog
				    
				    'Lastlog' feature.

   - A lot of nitty gritty details has been adjusted in favour of
     HP-UX, e.g. /etc/securetty, default paths and the environment
     variables assigned by 'login'.

   - We do *nothing* to setup/alter tty state, under HP-UX this is
     to be done by getty/rlogind/telnetd/some one else.

   Michael Glad (glad@daimi.dk)
   Computer Science Department
   Aarhus University
   Denmark

   1990-07-04

   1991-09-24 glad@daimi.aau.dk: HP-UX 8.0 port:
              - now explictly sets non-blocking mode on descriptors
	      - strcasecmp is now part of HP-UX
   1992-02-05 poe@daimi.aau.dk: Ported the stuff to Linux 0.12
   From 1992 till now (1995) this code for Linux has been maintained at
   ftp.daimi.aau.dk:/pub/linux/poe/
*/
   
/*
 * Copyright (c) 1980, 1987, 1988 The Regents of the University of California.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms are permitted
 * provided that the above copyright notice and this paragraph are
 * duplicated in all such forms and that any documentation,
 * advertising materials, and other materials related to such
 * distribution and use acknowledge that the software was developed
 * by the University of California, Berkeley.  The name of the
 * University may not be used to endorse or promote products derived
 * from this software without specific prior written permission.
 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
 * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
 */

#ifndef lint
char copyright[] =
"@(#) Copyright (c) 1980, 1987, 1988 The Regents of the University of California.\n\
 All rights reserved.\n";
#endif /* not lint */

#ifndef lint
static char sccsid[] = "@(#)login.c	5.40 (Berkeley) 5/9/89";
#endif /* not lint */

/*
 * login [ name ]
 * login -h hostname	(for telnetd, etc.)
 * login -f name	(for pre-authenticated login: datakit, xterm, etc.)
 */

/* #define TESTING */

#ifdef TESTING
#include "param.h"
#else
#include <sys/param.h>
#endif

#include <ctype.h>
#include <unistd.h>
#include <getopt.h>
#include <memory.h>
#include <sys/stat.h>
#include <sys/time.h>
#include <sys/resource.h>
#include <sys/file.h>
#include <termios.h>
#include <string.h>
#define index strchr
#define rindex strrchr
#include <sys/ioctl.h>
#include <signal.h>
#include <errno.h>
#include <grp.h>
#include <pwd.h>
#include <setjmp.h>
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <sys/syslog.h>
#include <sys/sysmacros.h>
#include <netdb.h>

#ifdef TESTING
#  include "utmp.h"
#else
#  include <utmp.h>
#endif

#ifdef SHADOW_PWD
#include <shadow.h>
#endif

#ifndef linux
#include <tzfile.h>
#endif
#include <lastlog.h>

#if 0
/* from before we had a lastlog.h file in linux */
struct  lastlog
  { long ll_time;
    char ll_line[12];
    char ll_host[16];
  };
#endif

#include "pathnames.h"

#define P_(s) ()
void opentty P_((const char *tty));
void getloginname P_((void));
void timedout P_((void));
int rootterm P_((char *ttyn));
void motd P_((void));
void sigint P_((void));
void checknologin P_((void));
void dolastlog P_((int quiet));
void badlogin P_((char *name));
char *stypeof P_((char *ttyid));
void checktty P_((char *user, char *tty, struct passwd *pwd));
void getstr P_((char *buf, int cnt, char *err));
void sleepexit P_((int eval));
#undef P_

#ifdef	KERBEROS
#include <kerberos/krb.h>
#include <sys/termios.h>
char	realm[REALM_SZ];
int	kerror = KSUCCESS, notickets = 1;
#endif

#define	TTYGRPNAME	"tty"		/* name of group to own ttys */
/**#  define TTYGRPNAME      "other" **/

#ifndef MAXPATHLEN
#  define MAXPATHLEN 1024
#endif

/*
 * This bounds the time given to login.  Not a define so it can
 * be patched on machines where it's too small.
 */
#ifndef linux
int	timeout = 300;
#else
int     timeout = 60;
#endif

struct	passwd *pwd;
int	failures = 1;
char	term[64], *hostname, *username, *tty;
struct  hostent hostaddress;
char	thishost[100];

#ifndef linux
struct	sgttyb sgttyb;
struct	tchars tc = {
	CINTR, CQUIT, CSTART, CSTOP, CEOT, CBRK
};
struct	ltchars ltc = {
	CSUSP, CDSUSP, CRPRNT, CFLUSH, CWERASE, CLNEXT
};
#endif

char *months[] =
	{ "Jan", "Feb", "Mar", "Apr", "May", "Jun", "Jul", "Aug",
	  "Sep", "Oct", "Nov", "Dec" };

/* provided by Linus Torvalds 16-Feb-93 */
void 
opentty(const char * tty)
{
    int i;
    int fd = open(tty, O_RDWR);

    for (i = 0 ; i < fd ; i++)
      close(i);
    for (i = 0 ; i < 3 ; i++)
      dup2(fd, i);
    if (fd >= 3)
      close(fd);
}

int
main(argc, argv)
	int argc;
	char **argv;
{
	extern int errno, optind;
	extern char *optarg, **environ;
	struct timeval tp;
	struct tm *ttp;
	struct group *gr;
	register int ch;
	register char *p;
	int ask, fflag, hflag, pflag, cnt;
	int quietlog, passwd_req, ioctlval;
	char *domain, *salt, *ttyn, *pp;
	char tbuf[MAXPATHLEN + 2], tname[sizeof(_PATH_TTY) + 10];
	char *ctime(), *ttyname(), *stypeof();
	time_t time();
	void timedout();
	char *termenv;

#ifdef linux
	char tmp[100];
	/* Just as arbitrary as mountain time: */
        /* (void)setenv("TZ", "MET-1DST",0); */
#endif

	(void)signal(SIGALRM, timedout);
	(void)alarm((unsigned int)timeout);
	(void)signal(SIGQUIT, SIG_IGN);
	(void)signal(SIGINT, SIG_IGN);

	(void)setpriority(PRIO_PROCESS, 0, 0);
#ifdef HAVE_QUOTA
	(void)quota(Q_SETUID, 0, 0, 0);
#endif

	/*
	 * -p is used by getty to tell login not to destroy the environment
 	 * -f is used to skip a second login authentication 
	 * -h is used by other servers to pass the name of the remote
	 *    host to login so that it may be placed in utmp and wtmp
	 */
	(void)gethostname(tbuf, sizeof(tbuf));
	(void)strncpy(thishost, tbuf, sizeof(thishost)-1);
	domain = index(tbuf, '.');

	hostname = NULL;
	fflag = hflag = pflag = 0;
	passwd_req = 1;
	while ((ch = getopt(argc, argv, "fh:p")) != EOF)
		switch (ch) {
		case 'f':
			fflag = 1;
			break;

		case 'h':
			if (getuid()) {
				(void)fprintf(stderr,
				    "login: -h for super-user only.\n");
				exit(1);
			}
			hflag = 1;
			if (domain && (p = index(optarg, '.')) &&
			    strcasecmp(p, domain) == 0)
				*p = 0;
			hostname = optarg;
			{ 
			    struct hostent *he = gethostbyname(hostname);
			    if (he) {
				memcpy(&hostaddress, he, sizeof(hostaddress));
			    } else {
				memset(&hostaddress, 0, sizeof(hostaddress));
			    }
			}
			break;

		case 'p':
			pflag = 1;
			break;
		case '?':
		default:
			(void)fprintf(stderr,
			    "usage: login [-fp] [username]\n");
			exit(1);
		}
	argc -= optind;
	argv += optind;
	if (*argv) {
		username = *argv;
		ask = 0;
	} else
		ask = 1;

#ifndef linux
	ioctlval = 0;
	(void)ioctl(0, TIOCLSET, &ioctlval);
	(void)ioctl(0, TIOCNXCL, 0);
	(void)fcntl(0, F_SETFL, ioctlval);
	(void)ioctl(0, TIOCGETP, &sgttyb);
	sgttyb.sg_erase = CERASE;
	sgttyb.sg_kill = CKILL;
	(void)ioctl(0, TIOCSLTC, &ltc);
	(void)ioctl(0, TIOCSETC, &tc);
	(void)ioctl(0, TIOCSETP, &sgttyb);

	/*
	 * Be sure that we're in
	 * blocking mode!!!
	 * This is really for HPUX
	 */
        ioctlval = 0;
        (void)ioctl(0, FIOSNBIO, &ioctlval);
#endif

	for (cnt = getdtablesize(); cnt > 2; cnt--)
		close(cnt);

	ttyn = ttyname(0);
	if (ttyn == NULL || *ttyn == '\0') {
		(void)sprintf(tname, "%s??", _PATH_TTY);
		ttyn = tname;
	}

	setpgrp();

	{
	    struct termios tt, ttt;

	    tcgetattr(0, &tt);
	    ttt = tt;
	    ttt.c_cflag &= ~HUPCL;

	    if((chown(ttyn, 0, 0) == 0) && (chmod(ttyn, 0622) == 0)) {
		tcsetattr(0,TCSAFLUSH,&ttt);
		signal(SIGHUP, SIG_IGN); /* so vhangup() wont kill us */
		vhangup();
		signal(SIGHUP, SIG_DFL);
	    }

	    setsid();

	    /* re-open stdin,stdout,stderr after vhangup() closed them */
	    /* if it did, after 0.99.5 it doesn't! */
	    opentty(ttyn);
	    tcsetattr(0,TCSAFLUSH,&tt);
	}

	if ((tty = rindex(ttyn, '/')))
		++tty;
	else
		tty = ttyn;

	openlog("login", LOG_ODELAY, LOG_AUTH);

	for (cnt = 0;; ask = 1) {
		ioctlval = 0;
#ifndef linux
		(void)ioctl(0, TIOCSETD, &ioctlval);
#endif

		if (ask) {
			fflag = 0;
			getloginname();
		}

               /* Dirty patch to fix a gigantic security hole when using 
                  yellow pages. This problem should be solved by the
                  libraries, and not by programs, but this must be fixed
                  urgently! If the first char of the username is '+', we 
                  avoid login success.
                  Feb 95 <alvaro@etsit.upm.es> */

		if (username[0] == '+') {
		    puts("Illegal username");
		    badlogin(username);
		    sleepexit(1);
		}

		(void)strcpy(tbuf, username);
		if ((pwd = getpwnam(username)))
			salt = pwd->pw_passwd;
		else
			salt = "xx";

		checktty(username, tty, pwd); /* in checktty.c */

		/* if user not super-user, check for disabled logins */
		if (pwd == NULL || pwd->pw_uid)
			checknologin();

		/*
		 * Disallow automatic login to root; if not invoked by
		 * root, disallow if the uid's differ.
		 */
		if (fflag && pwd) {
			int uid = getuid();

			passwd_req = pwd->pw_uid == 0 ||
			    (uid && uid != pwd->pw_uid);
		}

		/*
		 * If trying to log in as root, but with insecure terminal,
		 * refuse the login attempt.
		 */
		if (pwd && pwd->pw_uid == 0 && !rootterm(tty)) {
			(void)fprintf(stderr,
			    "%s login refused on this terminal.\n",
			    pwd->pw_name);

			if (hostname)
				syslog(LOG_NOTICE,
				    "LOGIN %s REFUSED FROM %s ON TTY %s",
				    pwd->pw_name, hostname, tty);
			else
				syslog(LOG_NOTICE,
				    "LOGIN %s REFUSED ON TTY %s",
				     pwd->pw_name, tty);
			continue;
		}

		/*
		 * If no pre-authentication and a password exists
		 * for this user, prompt for one and verify it.
		 */
		if (!passwd_req || (pwd && !*pwd->pw_passwd))
			break;

		setpriority(PRIO_PROCESS, 0, -4);
		pp = getpass("Password: ");
		p = crypt(pp, salt);
		setpriority(PRIO_PROCESS, 0, 0);

#ifdef	KERBEROS

		/*
		 * If not present in pw file, act as we normally would.
		 * If we aren't Kerberos-authenticated, try the normal
		 * pw file for a password.  If that's ok, log the user
		 * in without issueing any tickets.
		 */

		if (pwd && !krb_get_lrealm(realm,1)) {
			/*
			 * get TGT for local realm; be careful about uid's
			 * here for ticket file ownership
			 */
			(void)setreuid(geteuid(),pwd->pw_uid);
			kerror = krb_get_pw_in_tkt(pwd->pw_name, "", realm,
				"krbtgt", realm, DEFAULT_TKT_LIFE, pp);
			(void)setuid(0);
			if (kerror == INTK_OK) {
				memset(pp, 0, strlen(pp));
				notickets = 0;	/* user got ticket */
				break;
			}
		}
#endif
		(void) memset(pp, 0, strlen(pp));
		if (pwd && !strcmp(p, pwd->pw_passwd))
			break;

		(void)printf("Login incorrect\n");
		failures++;
		badlogin(username); /* log ALL bad logins */

		/* we allow 10 tries, but after 3 we start backing off */
		if (++cnt > 3) {
			if (cnt >= 10) {
				sleepexit(1);
			}
			sleep((unsigned int)((cnt - 3) * 5));
		}
	}

	/* committed to login -- turn off timeout */
	(void)alarm((unsigned int)0);

#ifdef HAVE_QUOTA
	if (quota(Q_SETUID, pwd->pw_uid, 0, 0) < 0 && errno != EINVAL) {
		switch(errno) {
		case EUSERS:
			(void)fprintf(stderr,
		"Too many users logged on already.\nTry again later.\n");
			break;
		case EPROCLIM:
			(void)fprintf(stderr,
			    "You have too many processes running.\n");
			break;
		default:
			perror("quota (Q_SETUID)");
		}
		sleepexit(0);
	}
#endif

	/* paranoia... */
	endpwent();

	/* This requires some explanation: As root we may not be able to
	   read the directory of the user if it is on an NFS mounted
	   filesystem. We temporarily set our effective uid to the user-uid
	   making sure that we keep root privs. in the real uid. 

	   A portable solution would require a fork(), but we rely on Linux
	   having the BSD setreuid() */

	{
	    char tmpstr[MAXPATHLEN];
	    uid_t ruid = getuid();
	    gid_t egid = getegid();

	    strncpy(tmpstr, pwd->pw_dir, MAXPATHLEN-12);
	    strncat(tmpstr, ("/" _PATH_HUSHLOGIN), MAXPATHLEN);

	    setregid(-1, pwd->pw_gid);
	    setreuid(0, pwd->pw_uid);
	    quietlog = (access(tmpstr, R_OK) == 0);
	    setuid(0); /* setreuid doesn't do it alone! */
	    setreuid(ruid, 0);
	    setregid(-1, egid);
	}

#ifndef linux
#ifdef KERBEROS
	if (notickets && !quietlog)
		(void)printf("Warning: no Kerberos tickets issued\n");
#endif

#define	TWOWEEKS	(14*24*60*60)
	if (pwd->pw_change || pwd->pw_expire)
		(void)gettimeofday(&tp, (struct timezone *)NULL);
	if (pwd->pw_change)
		if (tp.tv_sec >= pwd->pw_change) {
			(void)printf("Sorry -- your password has expired.\n");
			sleepexit(1);
		}
		else if (tp.tv_sec - pwd->pw_change < TWOWEEKS && !quietlog) {
			ttp = localtime(&pwd->pw_change);
			(void)printf("Warning: your password expires on %s %d, %d\n",
			    months[ttp->tm_mon], ttp->tm_mday, TM_YEAR_BASE + ttp->tm_year);
		}
	if (pwd->pw_expire)
		if (tp.tv_sec >= pwd->pw_expire) {
			(void)printf("Sorry -- your account has expired.\n");
			sleepexit(1);
		}
		else if (tp.tv_sec - pwd->pw_expire < TWOWEEKS && !quietlog) {
			ttp = localtime(&pwd->pw_expire);
			(void)printf("Warning: your account expires on %s %d, %d\n",
			    months[ttp->tm_mon], ttp->tm_mday, TM_YEAR_BASE + ttp->tm_year);
		}

	/* nothing else left to fail -- really log in */
	{
		struct utmp utmp;

		memset((char *)&utmp, 0, sizeof(utmp));
		(void)time(&utmp.ut_time);
		strncpy(utmp.ut_name, username, sizeof(utmp.ut_name));
		if (hostname)
			strncpy(utmp.ut_host, hostname, sizeof(utmp.ut_host));
		strncpy(utmp.ut_line, tty, sizeof(utmp.ut_line));
		login(&utmp);
	}
#else
	/* for linux, write entries in utmp and wtmp */
	{
		struct utmp ut;
		int wtmp;
		struct utmp *utp;
		pid_t mypid = getpid();

		utmpname(_PATH_UTMP);
		setutent();
		while ((utp = getutent()) 
		       && !(utp->ut_pid == mypid)) /* nothing */;

		if (utp) {
		    memcpy(&ut, utp, sizeof(ut));
		} else {
		    /* some gettys/telnetds don't initialize utmp... */
		    memset(&ut, 0, sizeof(ut));
		}
		endutent();

		if (ut.ut_id[0] == 0)
		  strncpy(ut.ut_id, ttyn + 8, sizeof(ut.ut_id));
	
		strncpy(ut.ut_user, username, sizeof(ut.ut_user));
		strncpy(ut.ut_line, ttyn + 5, sizeof(ut.ut_line));
		time(&ut.ut_time);
		ut.ut_type = USER_PROCESS;
		ut.ut_pid = mypid;
		if (hostname) {
		    strncpy(ut.ut_host, hostname, sizeof(ut.ut_host));
		    if (hostaddress.h_addr_list)
		      memcpy(&ut.ut_addr, hostaddress.h_addr_list[0],
			     sizeof(ut.ut_addr));
		}

		pututline(&ut);
		endutent();
		
		if((wtmp = open(_PATH_WTMP, O_APPEND|O_WRONLY)) >= 0) {
		        flock(wtmp, LOCK_EX);
			write(wtmp, (char *)&ut, sizeof(ut));
		        flock(wtmp, LOCK_UN);
			close(wtmp);
		}
	}
#endif

	dolastlog(quietlog);
	
#ifndef linux
	if (!hflag) {					/* XXX */
		static struct winsize win = { 0, 0, 0, 0 };

		(void)ioctl(0, TIOCSWINSZ, &win);
	}
#endif
	(void)chown(ttyn, pwd->pw_uid,
	    (gr = getgrnam(TTYGRPNAME)) ? gr->gr_gid : pwd->pw_gid);

#ifdef USE_TTY_GROUP
	chmod(ttyn, 0620);
#else
	chmod(ttyn, 0600);
#endif

	setgid(pwd->pw_gid);
	initgroups(username, pwd->pw_gid);

#ifdef HAVE_QUOTA
	quota(Q_DOWARN, pwd->pw_uid, (dev_t)-1, 0);
#endif

	if (*pwd->pw_shell == '\0')
		pwd->pw_shell = _PATH_BSHELL;
#ifndef linux
	/* turn on new line discipline for the csh */
	else if (!strcmp(pwd->pw_shell, _PATH_CSHELL)) {
		ioctlval = NTTYDISC;
		(void)ioctl(0, TIOCSETD, &ioctlval);
	}
#endif

	/* preserve TERM even without -p flag */
	{
		char *ep;
		
		if(!((ep = getenv("TERM")) && (termenv = strdup(ep))))
		  termenv = "dumb";
	}

	/* destroy environment unless user has requested preservation */
	if (!pflag)
        {
          environ = (char**)malloc(sizeof(char*));
	  memset(environ, 0, sizeof(char*));
	}

#ifndef linux
	(void)setenv("HOME", pwd->pw_dir, 1);
	(void)setenv("SHELL", pwd->pw_shell, 1);
	if (term[0] == '\0')
		strncpy(term, stypeof(tty), sizeof(term));
	(void)setenv("TERM", term, 0);
	(void)setenv("USER", pwd->pw_name, 1);
	(void)setenv("PATH", _PATH_DEFPATH, 0);
#else
        (void)setenv("HOME", pwd->pw_dir, 0);      /* legal to override */
        if(pwd->pw_uid)
          (void)setenv("PATH", _PATH_DEFPATH, 1);
        else
          (void)setenv("PATH", _PATH_DEFPATH_ROOT, 1);
	(void)setenv("SHELL", pwd->pw_shell, 1);
	(void)setenv("TERM", termenv, 1);

        /* mailx will give a funny error msg if you forget this one */
        (void)sprintf(tmp,"%s/%s",_PATH_MAILDIR,pwd->pw_name);
        (void)setenv("MAIL",tmp,0);

        /* LOGNAME is not documented in login(1) but
	   HP-UX 6.5 does it. We'll not allow modifying it.
	 */
	(void)setenv("LOGNAME", pwd->pw_name, 1);
#endif

	if (tty[sizeof("tty")-1] == 'S')
		syslog(LOG_INFO, "DIALUP %s, %s", tty, pwd->pw_name);

	if (pwd->pw_uid == 0)
		if (hostname)
			syslog(LOG_NOTICE, "ROOT LOGIN ON %s FROM %s",
			    tty, hostname);
		else
			syslog(LOG_NOTICE, "ROOT LOGIN ON %s", tty);

	if (!quietlog) {
		struct stat st;

		motd();
		(void)sprintf(tbuf, "%s/%s", _PATH_MAILDIR, pwd->pw_name);
		if (stat(tbuf, &st) == 0 && st.st_size != 0)
			(void)printf("You have %smail.\n",
			    (st.st_mtime > st.st_atime) ? "new " : "");
	}

	(void)signal(SIGALRM, SIG_DFL);
	(void)signal(SIGQUIT, SIG_DFL);
	(void)signal(SIGINT, SIG_DFL);
	(void)signal(SIGTSTP, SIG_IGN);
	(void)signal(SIGHUP, SIG_DFL);

	/* discard permissions last so can't get killed and drop core */
	if(setuid(pwd->pw_uid) < 0 && pwd->pw_uid) {
	    syslog(LOG_ALERT, "setuid() failed");
	    exit(1);
	}

	/* wait until here to change directory! */
	if (chdir(pwd->pw_dir) < 0) {
		(void)printf("No directory %s!\n", pwd->pw_dir);
		if (chdir("/"))
			exit(0);
		pwd->pw_dir = "/";
		(void)printf("Logging in with home = \"/\".\n");
	}

	/* if the shell field has a space: treat it like a shell script */
	if (strchr(pwd->pw_shell, ' ')) {
	    char *buff = malloc(strlen(pwd->pw_shell) + 6);
	    if (buff) {
		strcpy(buff, "exec ");
		strcat(buff, pwd->pw_shell);
		execlp("/bin/sh", "-sh", "-c", buff, (char *)0);
		fprintf(stderr, "login: couldn't exec shell script: %s.\n",
			strerror(errno));
		exit(0);
	    }
	    fprintf(stderr, "login: no memory for shell script.\n");
	    exit(0);
	}

	tbuf[0] = '-';
	strcpy(tbuf + 1, ((p = rindex(pwd->pw_shell, '/')) ?
			  p + 1 : pwd->pw_shell));

	execlp(pwd->pw_shell, tbuf, (char *)0);
	(void)fprintf(stderr, "login: no shell: %s.\n", strerror(errno));
	exit(0);
}

void
getloginname()
{
	register int ch;
	register char *p;
	static char nbuf[UT_NAMESIZE + 1];
	int cnt, cnt2;

	cnt2 = 0;
	for (;;) {
	        cnt = 0;
		(void)printf("\n%s login: ", thishost); fflush(stdout);
		for (p = nbuf; (ch = getchar()) != '\n'; ) {
			if (ch == EOF) {
				badlogin("EOF");
				exit(0);
			}
			if (p < nbuf + UT_NAMESIZE)
				*p++ = ch;

			cnt++;
			if (cnt > UT_NAMESIZE + 20) {
				fprintf(stderr, "login name much too long.\n");
				badlogin("NAME too long");
				exit(0);
			}
		}
		if (p > nbuf)
			if (nbuf[0] == '-')
				(void)fprintf(stderr,
				    "login names may not start with '-'.\n");
			else {
				*p = '\0';
				username = nbuf;
				break;
			}

		cnt2++;
		if (cnt2 > 50) {
			fprintf(stderr, "too many bare linefeeds.\n");
			badlogin("EXCESSIVE linefeeds");
			exit(0);
		}
	}
}

void timedout()
{
	struct termio ti;
	
	(void)fprintf(stderr, "Login timed out after %d seconds\n", timeout);

	/* reset echo */
	(void) ioctl(0, TCGETA, &ti);
	ti.c_lflag |= ECHO;
	(void) ioctl(0, TCSETA, &ti);
	exit(0);
}

int
rootterm(ttyn)
	char *ttyn;
#ifndef linux
{
	struct ttyent *t;

	return((t = getttynam(ttyn)) && t->ty_status&TTY_SECURE);
}
#else
{ 
  int fd;
  char buf[100],*p;
  int cnt, more;

  fd = open(SECURETTY, O_RDONLY);
  if(fd < 0) return 1;

  /* read each line in /etc/securetty, if a line matches our ttyline
     then root is allowed to login on this tty, and we should return
     true. */
  for(;;) {
	p = buf; cnt = 100;
	while(--cnt >= 0 && (more = read(fd, p, 1)) == 1 && *p != '\n') p++;
	if(more && *p == '\n') {
		*p = '\0';
	  	if(!strcmp(buf, ttyn)) {
  			close(fd);
  			return 1;
	  	} else
  			continue;
  	} else {
  		close(fd);
  		return 0;
  	}
  }
}
#endif

jmp_buf motdinterrupt;

void
motd()
{
	register int fd, nchars;
	void (*oldint)(), sigint();
	char tbuf[8192];

	if ((fd = open(_PATH_MOTDFILE, O_RDONLY, 0)) < 0)
		return;
	oldint = signal(SIGINT, sigint);
	if (setjmp(motdinterrupt) == 0)
		while ((nchars = read(fd, tbuf, sizeof(tbuf))) > 0)
			(void)write(fileno(stdout), tbuf, nchars);
	(void)signal(SIGINT, oldint);
	(void)close(fd);
}

void sigint()
{
	longjmp(motdinterrupt, 1);
}

void
checknologin()
{
	register int fd, nchars;
	char tbuf[8192];

	if ((fd = open(_PATH_NOLOGIN, O_RDONLY, 0)) >= 0) {
		while ((nchars = read(fd, tbuf, sizeof(tbuf))) > 0)
			(void)write(fileno(stdout), tbuf, nchars);
		sleepexit(0);
	}
}

void
dolastlog(quiet)
	int quiet;
{
	struct lastlog ll;
	int fd;

	if ((fd = open(_PATH_LASTLOG, O_RDWR, 0)) >= 0) {
		(void)lseek(fd, (off_t)pwd->pw_uid * sizeof(ll), L_SET);
		if (!quiet) {
			if (read(fd, (char *)&ll, sizeof(ll)) == sizeof(ll) &&
			    ll.ll_time != 0) {
				(void)printf("Last login: %.*s ",
				    24-5, (char *)ctime(&ll.ll_time));

				if (*ll.ll_host != '\0')
				  printf("from %.*s\n",
					 (int)sizeof(ll.ll_host), ll.ll_host);
				else
				  printf("on %.*s\n",
					 (int)sizeof(ll.ll_line), ll.ll_line);
			}
			(void)lseek(fd, (off_t)pwd->pw_uid * sizeof(ll), L_SET);
		}
		memset((char *)&ll, 0, sizeof(ll));
		(void)time(&ll.ll_time);
		strncpy(ll.ll_line, tty, sizeof(ll.ll_line));
		if (hostname)
			strncpy(ll.ll_host, hostname, sizeof(ll.ll_host));
		(void)write(fd, (char *)&ll, sizeof(ll));
		(void)close(fd);
	}
}

void
badlogin(name)
	char *name;
{
	if (hostname)
		syslog(LOG_NOTICE, "%d LOGIN FAILURE%s FROM %s, %s",
		    failures, failures > 1 ? "S" : "", hostname, name);
	else
		syslog(LOG_NOTICE, "%d LOGIN FAILURE%s ON %s, %s",
		    failures, failures > 1 ? "S" : "", tty, name);
}

#undef	UNKNOWN
#define	UNKNOWN	"su"

#ifndef linux
char *
stypeof(ttyid)
	char *ttyid;
{
	struct ttyent *t;

	return(ttyid && (t = getttynam(ttyid)) ? t->ty_type : UNKNOWN);
}
#endif 

void
getstr(buf, cnt, err)
	char *buf, *err;
	int cnt;
{
	char ch;

	do {
		if (read(0, &ch, sizeof(ch)) != sizeof(ch))
			exit(1);
		if (--cnt < 0) {
			(void)fprintf(stderr, "%s too long\r\n", err);
			sleepexit(1);
		}
		*buf++ = ch;
	} while (ch);
}

void
sleepexit(eval)
	int eval;
{
	sleep((unsigned int)5);
	exit(eval);
}