4.1cBSD/usr/src/bin/login.c
static char *sccsid = "@(#)login.c 4.20 82/12/21";
/*
* login [ name ]
* login -r
*/
#include <sys/types.h>
#include <sgtty.h>
#include <utmp.h>
#include <signal.h>
#include <pwd.h>
#include <stdio.h>
#include <sys/stat.h>
#include <lastlog.h>
#define SCPYN(a, b) strncpy(a, b, sizeof(a))
#define NMAX sizeof(utmp.ut_name)
#define LMAX sizeof(utmp.ut_line)
#define FALSE 0
#define TRUE -1
char nolog[] = "/etc/nologin";
char qlog[] = ".hushlogin";
char securetty[] = "/etc/securetty";
char maildir[30] = "/usr/spool/mail/";
char lastlog[] = "/usr/adm/lastlog";
struct passwd nouser = {"", "nope", -1, -1, -1, "", "", "", "" };
struct sgttyb ttyb;
struct utmp utmp;
char minusnam[16] = "-";
char homedir[64] = "HOME=";
char shell[64] = "SHELL=";
char term[64] = "TERM=";
char user[20] = "USER=";
char *speeds[] =
{ "0", "50", "75", "110", "134", "150", "200", "300",
"600", "1200", "1800", "2400", "4800", "9600", "19200", "38400" };
#define NSPEEDS (sizeof (speeds) / sizeof (speeds[0]))
char *envinit[] =
{homedir, shell, "PATH=:/usr/ucb:/bin:/usr/bin", term, user, 0};
struct passwd *pwd;
struct passwd *getpwnam();
char *strcat(), *rindex(), *index();
int setpwent();
char *ttyname();
char *crypt();
char *getpass();
char *rindex();
char *stypeof();
extern char **environ;
struct ttychars tc = {
CERASE, CKILL, CINTR, CQUIT, CSTART,
CSTOP, CEOF, CBRK, CSUSP, CDSUSP,
CRPRNT, CFLUSH, CWERASE,CLNEXT
};
int rflag;
char rusername[NMAX+1], lusername[NMAX+1];
char rpassword[NMAX+1];
char name[NMAX+1];
char *rhost;
main(argc, argv)
char **argv;
{
register char *namep;
int t, f, c;
int invalid;
int quietlog;
int i;
FILE *nlfd;
char *ttyn;
int ldisc = 0, zero = 0;
FILE *hostf; int first = 1;
alarm(60);
signal(SIGQUIT, SIG_IGN);
signal(SIGINT, SIG_IGN);
nice(-100);
nice(20);
nice(0);
if (argc > 1 && !strcmp(argv[1], "-r")) {
rflag++;
rhost = argv[2];
argc = 1;
getstr(rusername, sizeof (rusername), "remuser");
getstr(lusername, sizeof (lusername), "locuser");
getstr(term+5, sizeof(term)-5, "Terminal type");
if (getuid())
goto abnormal;
setpwent();
pwd = getpwnam(lusername);
endpwent();
if (pwd == NULL) {
if (strcmp(rusername, lusername))
printf("%s: No such user\r\n", lusername);
goto abnormal;
}
hostf = pwd->pw_uid ? fopen("/etc/hosts.equiv", "r") : 0;
again:
if (hostf) {
char ahost[32];
while (fgets(ahost, sizeof (ahost), hostf)) {
char *user;
if (index(ahost, '\n'))
*index(ahost, '\n') = 0;
user = index(ahost, ' ');
if (user)
*user++ = 0;
if (!strcmp(rhost, ahost) &&
!strcmp(rusername, user ? user : lusername)) {
fclose(hostf);
goto normal;
}
}
fclose(hostf);
}
if (first == 1) {
first = 0;
if (chdir(pwd->pw_dir) < 0)
goto again;
hostf = fopen(".rhosts", "r");
goto again;
}
abnormal:
rhost = 0;
rflag = -1;
}
normal:
ioctl(0, TIOCLSET, &zero); /* XXX */
ioctl(0, TIOCNXCL, 0);
ioctl(0, FIONBIO, &zero);
ioctl(0, FIOASYNC, &zero);
ioctl(0, TIOCGETP, &ttyb); /* XXX */
if (rflag) {
char *cp = index(term, '/');
if (cp) {
int i;
*cp++ = 0;
for (i = 0; i < NSPEEDS; i++)
if (!strcmp(speeds[i], cp)) {
ttyb.sg_ispeed = ttyb.sg_ospeed = i;
break;
}
}
ttyb.sg_flags = ECHO|CRMOD|ANYP|XTABS;
}
ioctl(0, TIOCSETP, &ttyb); /* XXX */
ioctl(0, TIOCCSET, &tc);
for (t=3; t<20; t++)
close(t);
ttyn = ttyname(0);
if (ttyn==(char *)0)
ttyn = "/dev/tty??";
do {
ldisc = 0;
ioctl(0, TIOCSETD, &ldisc);
invalid = FALSE;
SCPYN(utmp.ut_name, "");
if (argc>1) {
SCPYN(utmp.ut_name, argv[1]);
argc = 0;
}
if (rflag) {
SCPYN(utmp.ut_name, lusername);
if (rflag == -1)
rflag = 0;
} else
while (utmp.ut_name[0] == '\0') {
namep = utmp.ut_name;
{ char hostname[32];
gethostname(hostname, sizeof (hostname));
printf("%s login: ", hostname); }
while ((c = getchar()) != '\n') {
if (c == ' ')
c = '_';
if (c == EOF)
exit(0);
if (namep < utmp.ut_name+NMAX)
*namep++ = c;
}
}
if (rhost == 0) {
setpwent();
if ((pwd = getpwnam(utmp.ut_name)) == NULL)
pwd = &nouser;
endpwent();
}
if (!strcmp(pwd->pw_shell, "/bin/csh")) {
ldisc = NTTYDISC;
ioctl(0, TIOCSETD, &ldisc);
}
if (rhost == 0) {
if (*pwd->pw_passwd != '\0') {
char *pp;
nice(-4);
if (rflag == 0)
pp = getpass("Password:");
else
pp = rpassword;
namep = crypt(pp,pwd->pw_passwd);
nice(4);
if (strcmp(namep, pwd->pw_passwd))
invalid = TRUE;
}
}
if (pwd->pw_uid != 0 && (nlfd = fopen(nolog, "r")) > 0) {
/* logins are disabled except for root */
while ((c = getc(nlfd)) != EOF)
putchar(c);
fflush(stdout);
sleep(5);
exit(0);
}
if (!invalid && pwd->pw_uid == 0 &&
!rootterm(ttyn+sizeof("/dev/")-1)) {
logerr("ROOT LOGIN REFUSED %s",
ttyn+sizeof("/dev/")-1);
invalid = TRUE;
}
if (invalid) {
printf("Login incorrect\n");
if (ttyn[sizeof("/dev/tty")-1] == 'd')
logerr("BADDIALUP %s %s\n",
ttyn+sizeof("/dev/")-1, utmp.ut_name);
}
if (*pwd->pw_shell == '\0')
pwd->pw_shell = "/bin/sh";
i = strlen(pwd->pw_shell);
if (chdir(pwd->pw_dir) < 0 && !invalid ) {
if (chdir("/") < 0) {
printf("No directory!\n");
invalid = TRUE;
} else {
printf("No directory! Logging in with home=/\n");
pwd->pw_dir = "/";
}
}
if (rflag && invalid)
exit(1);
} while (invalid);
time(&utmp.ut_time);
t = ttyslot();
if (t>0 && (f = open("/etc/utmp", 1)) >= 0) {
lseek(f, (long)(t*sizeof(utmp)), 0);
SCPYN(utmp.ut_line, rindex(ttyn, '/')+1);
write(f, (char *)&utmp, sizeof(utmp));
close(f);
}
if (t>0 && (f = open("/usr/adm/wtmp", 1)) >= 0) {
lseek(f, 0L, 2);
write(f, (char *)&utmp, sizeof(utmp));
close(f);
}
quietlog = 0;
if (access(qlog, 0) == 0)
quietlog = 1;
if ((f = open(lastlog, 2)) >= 0) {
struct lastlog ll;
lseek(f, (long)pwd->pw_uid * sizeof (struct lastlog), 0);
if (read(f, (char *) &ll, sizeof ll) == sizeof ll &&
ll.ll_time != 0) {
if (quietlog == 0)
printf("Last login: %.*s on %.*s\n"
, 24-5
, (char *) ctime(&ll.ll_time)
, sizeof(ll.ll_line)
, ll.ll_line
);
}
lseek(f, (long)pwd->pw_uid * sizeof (struct lastlog), 0);
time(&ll.ll_time);
SCPYN(ll.ll_line, rindex(ttyn, '/')+1);
write(f, (char *) &ll, sizeof ll);
close(f);
}
chown(ttyn, pwd->pw_uid, pwd->pw_gid);
chmod(ttyn, 0622);
setgid(pwd->pw_gid);
strncpy(name, utmp.ut_name, NMAX);
name[NMAX] = '\0';
initgroups(name, pwd->pw_gid);
setuid(pwd->pw_uid);
environ = envinit;
strncat(homedir, pwd->pw_dir, sizeof(homedir)-6);
strncat(shell, pwd->pw_shell, sizeof(shell)-7);
if (term[strlen("TERM=")] == 0)
strncat(term, stypeof(ttyn), sizeof(term)-6);
strncat(user, pwd->pw_name, sizeof(user)-6);
if ((namep = rindex(pwd->pw_shell, '/')) == NULL)
namep = pwd->pw_shell;
else
namep++;
strcat(minusnam, namep);
alarm(0);
umask(022);
if (ttyn[sizeof("/dev/tty")-1] == 'd')
logerr("DIALUP %s %s\n", ttyn+sizeof("/dev/")-1, pwd->pw_name);
if (!quietlog) {
showmotd();
strcat(maildir, pwd->pw_name);
if (access(maildir,4)==0) {
struct stat statb;
stat(maildir, &statb);
if (statb.st_size)
printf("You have mail.\n");
}
}
signal(SIGQUIT, SIG_DFL);
signal(SIGINT, SIG_DFL);
signal(SIGTSTP, SIG_IGN);
execlp(pwd->pw_shell, minusnam, 0);
perror(pwd->pw_shell);
printf("No shell\n");
exit(0);
}
int stopmotd;
catch()
{
signal(SIGINT, SIG_IGN);
stopmotd++;
}
rootterm(tty)
char *tty;
{
register FILE *fd;
char buf[100];
if (rflag)
return(1);
if ((fd = fopen(securetty, "r")) == NULL)
return(1);
while (fgets(buf, sizeof buf, fd) != NULL) {
buf[strlen(buf)-1] = '\0';
if (strcmp(tty, buf) == 0) {
fclose(fd);
return(1);
}
}
fclose(fd);
return(0);
}
showmotd()
{
FILE *mf;
register c;
signal(SIGINT, catch);
if ((mf = fopen("/etc/motd","r")) != NULL) {
while ((c = getc(mf)) != EOF && stopmotd == 0)
putchar(c);
fclose(mf);
}
signal(SIGINT, SIG_IGN);
}
#undef UNKNOWN
#define UNKNOWN "su"
char *
stypeof(ttyid)
char *ttyid;
{
static char typebuf[16];
char buf[50];
register FILE *f;
register char *p, *t, *q;
if (ttyid == NULL)
return (UNKNOWN);
f = fopen("/etc/ttytype", "r");
if (f == NULL)
return (UNKNOWN);
/* split off end of name */
for (p = q = ttyid; *p != 0; p++)
if (*p == '/')
q = p + 1;
/* scan the file */
while (fgets(buf, sizeof buf, f) != NULL)
{
for (t=buf; *t!=' ' && *t != '\t'; t++)
;
*t++ = 0;
while (*t == ' ' || *t == '\t')
t++;
for (p=t; *p>' '; p++)
;
*p = 0;
if (strcmp(q,t)==0) {
strcpy(typebuf, buf);
fclose(f);
return (typebuf);
}
}
fclose (f);
return (UNKNOWN);
}
getstr(buf, cnt, err)
char *buf;
int cnt;
char *err;
{
char c;
do {
if (read(0, &c, 1) != 1)
exit(1);
if (--cnt < 0) {
printf("%s too long\r\n", err);
exit(1);
}
*buf++ = c;
} while (c != 0);
}
logerr(fmt, a1, a2, a3)
char *fmt, *a1, *a2, *a3;
{
}