xref: /original-bsd/usr.bin/login/login.c.1 (revision 1e7fda44)
1static	char *sccsid = "@(#)login.c.1	4.16 82/04/03";
2/*
3 * login [ name ]
4 * login -r
5 */
6
7#include <sys/types.h>
8#include <sgtty.h>
9#include <utmp.h>
10#include <signal.h>
11#include <pwd.h>
12#include <stdio.h>
13#include <sys/stat.h>
14#include <lastlog.h>
15
16#define	SCPYN(a, b)	strncpy(a, b, sizeof(a))
17
18#define NMAX	sizeof(utmp.ut_name)
19#define LMAX	sizeof(utmp.ut_line)
20
21#define	FALSE	0
22#define	TRUE	-1
23
24char	nolog[] =	"/etc/nologin";
25char	qlog[]  =	".hushlogin";
26char	securetty[] =	"/etc/securetty";
27char	maildir[30] =	"/usr/spool/mail/";
28char	lastlog[] =	"/usr/adm/lastlog";
29struct	passwd nouser = {"", "nope"};
30struct	sgttyb ttyb;
31struct	utmp utmp;
32char	minusnam[16] = "-";
33
34char	homedir[64] = "HOME=";
35char	shell[64] = "SHELL=";
36char	term[64] = "TERM=";
37char	user[20] = "USER=";
38char	*speeds[] =
39    { "0", "50", "75", "110", "134", "150", "200", "300",
40      "600", "1200", "1800", "2400", "4800", "9600", "19200", "38400" };
41#define	NSPEEDS	(sizeof (speeds) / sizeof (speeds[0]))
42
43char	*envinit[] =
44    {homedir, shell, "PATH=:/usr/ucb:/bin:/usr/bin", term, user, 0};
45
46struct	passwd *pwd;
47struct	passwd *getpwnam();
48char	*strcat(), *rindex(), *index();
49int	setpwent();
50char	*ttyname();
51char	*crypt();
52char	*getpass();
53char	*rindex();
54char	*stypeof();
55extern	char **environ;
56
57#define	CTRL(c)	('c'&037)
58#define	CERASE	'#'
59#define	CEOT	CTRL(d)
60#define	CKILL	'@'
61#define	CQUIT	034		/* FS, cntl shift L */
62#define	CINTR	0177		/* DEL */
63#define	CSTOP	CTRL(s)
64#define	CSTART	CTRL(q)
65#define	CBRK	0377
66struct	tchars tc = {
67	CINTR, CQUIT, CSTART, CSTOP, CEOT, CBRK
68};
69struct	ltchars ltc = {
70	CTRL(z), CTRL(y), CTRL(r), CTRL(o), CTRL(w), CTRL(v)
71};
72
73int	rflag;
74char	rusername[NMAX+1], lusername[NMAX+1];
75char	rpassword[NMAX+1];
76char	*rhost;
77
78main(argc, argv)
79char **argv;
80{
81	register char *namep;
82	int t, f, c;
83	int invalid;
84	int quietlog;
85	int i;
86	FILE *nlfd;
87	char *ttyn;
88	int ldisc = 0, zero = 0;
89	FILE *hostf; int first = 1;
90
91	alarm(60);
92	signal(SIGQUIT, SIG_IGN);
93	signal(SIGINT, SIG_IGN);
94	nice(-100);
95	nice(20);
96	nice(0);
97	if (argc > 1 && !strcmp(argv[1], "-r")) {
98		rflag++;
99		rhost = argv[2];
100		argc = 1;
101		getstr(rusername, sizeof (rusername), "remuser");
102		getstr(lusername, sizeof (lusername), "locuser");
103		getstr(term+5, sizeof(term)-5, "Terminal type");
104		if (getuid())
105			goto abnormal;
106		setpwent();
107		pwd = getpwnam(lusername);
108		endpwent();
109		if (pwd == NULL) {
110			if (strcmp(rusername, lusername))
111				printf("%s: No such user\r\n", lusername);
112			goto abnormal;
113		}
114		hostf = pwd->pw_uid ? fopen("/etc/hosts.equiv", "r") : 0;
115	again:
116		if (hostf) {
117		  char ahost[32];
118		  while (fgets(ahost, sizeof (ahost), hostf)) {
119			char *user;
120			if (index(ahost, '\n'))
121				*index(ahost, '\n') = 0;
122			user = index(ahost, ' ');
123			if (user)
124				*user++ = 0;
125			if (!strcmp(rhost, ahost) &&
126			    !strcmp(rusername, user ? user : lusername)) {
127				fclose(hostf);
128				goto normal;
129			}
130		  }
131		  fclose(hostf);
132		}
133		if (first == 1) {
134			first = 0;
135			if (chdir(pwd->pw_dir) < 0)
136				goto again;
137			hostf = fopen(".rhosts", "r");
138			goto again;
139		}
140abnormal:
141		rhost = 0;
142		rflag = -1;
143	}
144normal:
145	ioctl(0, TIOCLSET, &zero);
146	ioctl(0, TIOCNXCL, 0);
147	ioctl(0, FIONBIO, &zero);
148	ioctl(0, FIOASYNC, &zero);
149	gtty(0, &ttyb);
150	if (rflag) {
151		char *cp = index(term, '/');
152		if (cp) {
153			int i;
154			*cp++ = 0;
155			for (i = 0; i < NSPEEDS; i++)
156				if (!strcmp(speeds[i], cp)) {
157					ttyb.sg_ispeed = ttyb.sg_ospeed = i;
158					break;
159				}
160		}
161		ttyb.sg_flags = ECHO|CRMOD|ANYP|XTABS;
162	}
163	ttyb.sg_erase = CERASE;
164	ttyb.sg_kill = CKILL;
165	stty(0, &ttyb);
166	ioctl(0, TIOCSETC, &tc);
167	ioctl(0, TIOCSLTC, &ltc);
168	for (t=3; t<20; t++)
169		close(t);
170	ttyn = ttyname(0);
171	if (ttyn==(char *)0)
172		ttyn = "/dev/tty??";
173	do {
174		ldisc = 0;
175		ioctl(0, TIOCSETD, &ldisc);
176		invalid = FALSE;
177		SCPYN(utmp.ut_name, "");
178		if (argc>1) {
179			SCPYN(utmp.ut_name, argv[1]);
180			argc = 0;
181		}
182		if (rflag) {
183			strcpy(utmp.ut_name, lusername);
184			if (rflag == -1)
185				rflag = 0;
186		} else
187			while (utmp.ut_name[0] == '\0') {
188				namep = utmp.ut_name;
189				{ char hostname[32];
190				  gethostname(hostname, sizeof (hostname));
191				  printf("%s login: ", hostname); }
192				while ((c = getchar()) != '\n') {
193					if (c == ' ')
194						c = '_';
195					if (c == EOF)
196						exit(0);
197					if (namep < utmp.ut_name+NMAX)
198						*namep++ = c;
199				}
200			}
201		if (rhost == 0) {
202			setpwent();
203			if ((pwd = getpwnam(utmp.ut_name)) == NULL)
204				pwd = &nouser;
205			endpwent();
206		}
207		if (!strcmp(pwd->pw_shell, "/bin/csh")) {
208			ldisc = NTTYDISC;
209			ioctl(0, TIOCSETD, &ldisc);
210		}
211		if (rhost == 0) {
212			if (*pwd->pw_passwd != '\0') {
213				char *pp;
214				nice(-4);
215				if (rflag == 0)
216					pp = getpass("Password:");
217				else
218					pp = rpassword;
219				namep = crypt(pp,pwd->pw_passwd);
220				nice(4);
221				if (strcmp(namep, pwd->pw_passwd))
222					invalid = TRUE;
223			}
224		}
225		if (pwd->pw_uid != 0 && (nlfd = fopen(nolog, "r")) > 0) {
226			/* logins are disabled except for root */
227			while ((c = getc(nlfd)) != EOF)
228				putchar(c);
229			fflush(stdout);
230			sleep(5);
231			exit(0);
232		}
233		if (!invalid && pwd->pw_uid == 0 &&
234		    !rootterm(ttyn+sizeof("/dev/")-1)) {
235			logerr("ROOT LOGIN REFUSED %s",
236			    ttyn+sizeof("/dev/")-1);
237			invalid = TRUE;
238		}
239		if (invalid) {
240			printf("Login incorrect\n");
241			if (ttyn[sizeof("/dev/tty")-1] == 'd')
242				logerr("BADDIALUP %s %s\n",
243				    ttyn+sizeof("/dev/")-1, utmp.ut_name);
244		}
245		if (*pwd->pw_shell == '\0')
246			pwd->pw_shell = "/bin/sh";
247		i = strlen(pwd->pw_shell);
248		if (chdir(pwd->pw_dir) < 0 && !invalid ) {
249			if (chdir("/") < 0) {
250				printf("No directory!\n");
251				invalid = TRUE;
252			} else {
253				printf("No directory!  Logging in with home=/\n");
254				pwd->pw_dir = "/";
255			}
256		}
257		if (rflag && invalid)
258			exit(1);
259	} while (invalid);
260
261
262	time(&utmp.ut_time);
263	t = ttyslot();
264	if (t>0 && (f = open("/etc/utmp", 1)) >= 0) {
265		lseek(f, (long)(t*sizeof(utmp)), 0);
266		SCPYN(utmp.ut_line, rindex(ttyn, '/')+1);
267		write(f, (char *)&utmp, sizeof(utmp));
268		close(f);
269	}
270	if (t>0 && (f = open("/usr/adm/wtmp", 1)) >= 0) {
271		lseek(f, 0L, 2);
272		write(f, (char *)&utmp, sizeof(utmp));
273		close(f);
274	}
275	quietlog = 0;
276	if (access(qlog, 0) == 0)
277		quietlog = 1;
278	if ((f = open(lastlog, 2)) >= 0) {
279		struct lastlog ll;
280
281		lseek(f, (long)pwd->pw_uid * sizeof (struct lastlog), 0);
282		if (read(f, (char *) &ll, sizeof ll) == sizeof ll &&
283		    ll.ll_time != 0) {
284			if (quietlog == 0)
285			printf("Last login: %.*s on %.*s\n"
286			    , 24-5
287			    , (char *) ctime(&ll.ll_time)
288			    , sizeof(ll.ll_line)
289			    , ll.ll_line
290			);
291		}
292		lseek(f, (long)pwd->pw_uid * sizeof (struct lastlog), 0);
293		time(&ll.ll_time);
294		SCPYN(ll.ll_line, rindex(ttyn, '/')+1);
295		write(f, (char *) &ll, sizeof ll);
296		close(f);
297	}
298	chown(ttyn, pwd->pw_uid, pwd->pw_gid);
299	setgid(pwd->pw_gid);
300	inigrp(utmp.ut_name, pwd->pw_gid);
301	setuid(pwd->pw_uid);
302	environ = envinit;
303	strncat(homedir, pwd->pw_dir, sizeof(homedir)-6);
304	strncat(shell, pwd->pw_shell, sizeof(shell)-7);
305	if (term[strlen("TERM=")] == 0)
306		strncat(term, stypeof(ttyn), sizeof(term)-6);
307	strncat(user, pwd->pw_name, sizeof(user)-6);
308	if ((namep = rindex(pwd->pw_shell, '/')) == NULL)
309		namep = pwd->pw_shell;
310	else
311		namep++;
312	strcat(minusnam, namep);
313	alarm(0);
314	umask(022);
315	if (ttyn[sizeof("/dev/tty")-1] == 'd')
316		logerr("DIALUP %s %s\n", ttyn+sizeof("/dev/")-1, pwd->pw_name);
317	if (!quietlog) {
318		showmotd();
319		strcat(maildir, pwd->pw_name);
320		if (access(maildir,4)==0) {
321			struct stat statb;
322			stat(maildir, &statb);
323			if (statb.st_size)
324				printf("You have mail.\n");
325		}
326	}
327
328	signal(SIGQUIT, SIG_DFL);
329	signal(SIGINT, SIG_DFL);
330	signal(SIGTSTP, SIG_IGN);
331	execlp(pwd->pw_shell, minusnam, 0);
332	perror(pwd->pw_shell);
333	printf("No shell\n");
334	exit(0);
335}
336
337int	stopmotd;
338catch()
339{
340
341	signal(SIGINT, SIG_IGN);
342	stopmotd++;
343}
344
345rootterm(tty)
346	char *tty;
347{
348	register FILE *fd;
349	char buf[100];
350
351	if (rflag)
352		return(1);
353	if ((fd = fopen(securetty, "r")) == NULL)
354		return(1);
355	while (fgets(buf, sizeof buf, fd) != NULL) {
356		buf[strlen(buf)-1] = '\0';
357		if (strcmp(tty, buf) == 0) {
358			fclose(fd);
359			return(1);
360		}
361	}
362	fclose(fd);
363	return(0);
364}
365
366showmotd()
367{
368	FILE *mf;
369	register c;
370
371	signal(SIGINT, catch);
372	if ((mf = fopen("/etc/motd","r")) != NULL) {
373		while ((c = getc(mf)) != EOF && stopmotd == 0)
374			putchar(c);
375		fclose(mf);
376	}
377	signal(SIGINT, SIG_IGN);
378}
379
380#undef	UNKNOWN
381#define UNKNOWN "su"
382
383char *
384stypeof(ttyid)
385char	*ttyid;
386{
387	static char	typebuf[16];
388	char		buf[50];
389	register FILE	*f;
390	register char	*p, *t, *q;
391
392	if (ttyid == NULL)
393		return (UNKNOWN);
394	f = fopen("/etc/ttytype", "r");
395	if (f == NULL)
396		return (UNKNOWN);
397	/* split off end of name */
398	for (p = q = ttyid; *p != 0; p++)
399		if (*p == '/')
400			q = p + 1;
401
402	/* scan the file */
403	while (fgets(buf, sizeof buf, f) != NULL)
404	{
405		for (t=buf; *t!=' ' && *t != '\t'; t++)
406			;
407		*t++ = 0;
408		while (*t == ' ' || *t == '\t')
409			t++;
410		for (p=t; *p>' '; p++)
411			;
412		*p = 0;
413		if (strcmp(q,t)==0) {
414			strcpy(typebuf, buf);
415			fclose(f);
416			return (typebuf);
417		}
418	}
419	fclose (f);
420	return (UNKNOWN);
421}
422
423getstr(buf, cnt, err)
424	char *buf;
425	int cnt;
426	char *err;
427{
428	char c;
429
430	do {
431		if (read(0, &c, 1) != 1)
432			exit(1);
433		if (--cnt < 0) {
434			printf("%s too long\r\n", err);
435			exit(1);
436		}
437		*buf++ = c;
438	} while (c != 0);
439}
440
441logerr(fmt, a1, a2, a3)
442	char *fmt, *a1, *a2, *a3;
443{
444
445}
446