1/*
2 * CDDL HEADER START
3 *
4 * The contents of this file are subject to the terms of the
5 * Common Development and Distribution License (the "License").
6 * You may not use this file except in compliance with the License.
7 *
8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9 * or http://www.opensolaris.org/os/licensing.
10 * See the License for the specific language governing permissions
11 * and limitations under the License.
12 *
13 * When distributing Covered Code, include this CDDL HEADER in each
14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15 * If applicable, add the following below this CDDL HEADER, with the
16 * fields enclosed by brackets "[]" replaced with your own identifying
17 * information: Portions Copyright [yyyy] [name of copyright owner]
18 *
19 * CDDL HEADER END
20 */
21
22/*
23 * Copyright 2008 Sun Microsystems, Inc.  All rights reserved.
24 * Use is subject to license terms.
25 */
26/*	Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T	*/
27/*	  All Rights Reserved  	*/
28
29#include	<stdio.h>
30#include	<stdlib.h>
31#include	<unistd.h>
32#include	<fcntl.h>
33#include	<errno.h>
34#include	<ctype.h>
35#include	<string.h>
36#include	<signal.h>
37#include	<sys/stat.h>
38#include	<utmpx.h>
39#include	<pwd.h>
40#include	<dirent.h>
41#include	<sys/param.h>
42#include	<sys/acl.h>
43#include	<sys/stat.h>
44#include	<sys/types.h>
45#include	<sys/console.h>
46#include	"ttymon.h"
47#include	"tmextern.h"
48#include	"tmstruct.h"
49
50static	char	devbuf[BUFSIZ];
51static	char	*devname;
52
53static	int	parse_args();
54static	void	ttymon_options();
55static	void	getty_options();
56static	void	usage();
57static	char	*find_ttyname();
58
59extern	void	tmchild();
60extern	int	vml();
61
62void		revokedevaccess(char *, uid_t, gid_t, mode_t);
63/* cannot include libdevinfo.h */
64extern int di_devperm_logout(const char *);
65
66/*
67 * ttymon_express - This is call when ttymon is invoked with args
68 *		    or invoked as getty
69 *		  - This special version of ttymon will monitor
70 *		    one port only
71 *		  - It is intended to be used when some process
72 *		    wants to have a login session on the fly
73 */
74void
75ttymon_express(int argc, char **argv)
76{
77	struct	pmtab	*pmtab;
78	struct	sigaction	sigact;
79	extern	int	Retry;
80	extern	void	open_device();
81	extern	void	read_ttydefs();
82	extern	int	checkut_line();
83#ifdef	DEBUG
84	extern	FILE	*Debugfp;
85	extern	void	opendebug();
86#endif
87
88#ifdef	DEBUG
89	opendebug(TRUE);
90#endif
91
92	sigact.sa_flags = 0;
93	sigact.sa_handler = SIG_IGN;
94	(void) sigemptyset(&sigact.sa_mask);
95	(void) sigaction(SIGINT, &sigact, NULL);
96
97	if ((pmtab = ALLOC_PMTAB) == PNULL) {
98		log("ttymon_express: ALLOC_PMTAB failed");
99		exit(1);
100	}
101
102	if (parse_args(argc, argv, pmtab) != 0) {
103		log("ttymon_express: parse_args failed");
104		exit(1);
105	}
106
107	read_ttydefs(NULL, FALSE);
108
109	if ((pmtab->p_device != NULL) && (*(pmtab->p_device) != '\0'))
110		while (checkut_line(pmtab->p_device))
111			sleep(15);
112
113	if ((pmtab->p_device == NULL) || (*(pmtab->p_device) == '\0')) {
114		devname = find_ttyname(0);
115		if ((devname == NULL) || (*devname == '\0')) {
116			log("ttyname cannot find the device on fd 0");
117			exit(1);
118		}
119		pmtab->p_device = devname;
120#ifdef	DEBUG
121		debug("ttymon_express: devname = %s", devname);
122#endif
123		/*
124		 * become session leader
125		 * fd 0 is closed and reopened just to make sure
126		 * controlling tty is set up right
127		 */
128		(void) setsid();
129		(void) close(0);
130		revokedevaccess(pmtab->p_device, 0, 0, 0);
131		if (open(pmtab->p_device, O_RDWR) < 0) {
132			log("open %s failed: %s", pmtab->p_device,
133			    strerror(errno));
134			exit(1);
135		}
136		if ((pmtab->p_modules != NULL) &&
137		    (*(pmtab->p_modules) != '\0')) {
138			if (push_linedisc(0, pmtab->p_modules,
139			    pmtab->p_device) == -1)
140				exit(1);
141		}
142		if (initial_termio(0, pmtab) == -1)
143			exit(1);
144		di_devperm_logout((const char *)pmtab->p_device);
145	} else {
146		(void) setsid();
147		(void) close(0);
148		Retry = FALSE;
149		open_device(pmtab);
150		if (Retry)		/* open failed */
151			exit(1);
152	}
153	tmchild(pmtab);
154	exit(1);	/*NOTREACHED*/
155}
156
157/*
158 * parse_arg	- parse cmd line arguments
159 */
160static	int
161parse_args(int argc, char **argv, struct pmtab *pmtab)
162{
163	static	char	p_server[] = "/usr/bin/login";
164	extern	char	*lastname();
165	extern	void	getty_account();
166	static	char	termbuf[MAX_TERM_TYPE_LEN];
167	static	struct	cons_getterm cnterm = {sizeof (termbuf), termbuf};
168
169	/* initialize fields to some default first */
170	pmtab->p_tag = "";
171	pmtab->p_flags = 0;
172	pmtab->p_identity = "root";
173	pmtab->p_res1 = "reserved";
174	pmtab->p_res2 = "reserved";
175	pmtab->p_res3 = "reserved";
176	pmtab->p_uid = 0;
177	pmtab->p_gid = 0;
178	pmtab->p_dir = "/";
179	pmtab->p_ttyflags = 0;
180	pmtab->p_count = 0;
181	pmtab->p_server = p_server;
182	pmtab->p_timeout = 0;
183	pmtab->p_modules = "";
184	pmtab->p_prompt = "login: ";
185	pmtab->p_dmsg = "";
186	pmtab->p_termtype = "";
187	pmtab->p_device = "";
188	pmtab->p_status = GETTY;
189	if (strcmp(lastname(argv[0]), "getty") == 0) {
190		pmtab->p_ttylabel = "300";
191		getty_options(argc, argv, pmtab);
192	} else {
193		int	cn_fd;
194
195		pmtab->p_ttylabel = "9600";
196		ttymon_options(argc, argv, pmtab);
197
198		/*
199		 * The following code is only reached if -g was specified.
200		 * It attempts to determine a suitable terminal type for
201		 * the console login process.
202		 *
203		 * If -d /dev/console also specified, we send an ioctl
204		 * to the console device to query the TERM type.
205		 *
206		 * If any of the tests, system calls, or ioctls fail
207		 * then pmtab->p_termtype retains its default value
208		 * of "".  otherwise it is set to a term type value
209		 * that was returned.
210		 */
211		if ((strlen(pmtab->p_termtype) == 0) &&
212		    (strcmp(pmtab->p_device, "/dev/console") == 0) &&
213		    ((cn_fd = open("/dev/console", O_RDONLY)) != -1)) {
214
215			if (ioctl(cn_fd, CONS_GETTERM, &cnterm) != -1)
216				pmtab->p_termtype = cnterm.cn_term_type;
217			(void) close(cn_fd);
218		}
219	}
220
221	if ((pmtab->p_device != NULL) && (*(pmtab->p_device) != '\0'))
222		getty_account(pmtab->p_device); /* utmp accounting */
223	return (0);
224}
225
226
227/*
228 * 	ttymon_options - scan and check args for ttymon express
229 */
230
231static	void
232ttymon_options(int argc, char **argv, struct pmtab *pmtab)
233{
234	int 	c;			/* option letter */
235	char 	*timeout;
236	int  	gflag = 0;		/* -g seen */
237	int	size = 0;
238	char	tbuf[BUFSIZ];
239
240	extern	char	*optarg;
241	extern	int	optind;
242	extern	void	copystr();
243	extern	char	*strsave();
244	extern	char	*getword();
245
246	while ((c = getopt(argc, argv, "T:gd:ht:p:m:l:")) != -1) {
247		switch (c) {
248		case 'g':
249			gflag = 1;
250			break;
251		case 'd':
252			pmtab->p_device = optarg;
253			break;
254		case 'h':
255			pmtab->p_ttyflags &= ~H_FLAG;
256			break;
257
258		case 'T':
259			pmtab->p_termtype = optarg;
260			break;
261/*
262 *		case 'b':
263 *			pmtab->p_ttyflags |= B_FLAG;
264 *			pmtab->p_ttyflags |= R_FLAG;
265 *			break;
266 */
267		case 't':
268			timeout = optarg;
269			while (*optarg) {
270				if (!isdigit(*optarg++)) {
271					log("Invalid argument for "
272					    "\"-t\" -- number expected.");
273					usage();
274				}
275			}
276			pmtab->p_timeout = atoi(timeout);
277			break;
278		case 'p':
279			copystr(tbuf, optarg);
280			pmtab->p_prompt = strsave(getword(tbuf, &size, TRUE));
281			break;
282		case 'm':
283			pmtab->p_modules = optarg;
284			if (vml(pmtab->p_modules) != 0)
285				usage();
286			break;
287		case 'l':
288			pmtab->p_ttylabel = optarg;
289			break;
290		case '?':
291			usage();
292			break;	/*NOTREACHED*/
293		}
294	}
295	if (optind < argc)
296		usage();
297
298	if (!gflag)
299		usage();
300}
301
302/*
303 * usage - print out a usage message
304 */
305
306static 	void
307usage()
308{
309	char	*umsg = "Usage: ttymon\n  ttymon -g [-h] [-d device] "
310	    "[-l ttylabel] [-t timeout] [-p prompt] [-m modules]\n";
311
312	if (isatty(STDERR_FILENO))
313		(void) fprintf(stderr, "%s", umsg);
314	else
315		cons_printf(umsg);
316	exit(1);
317}
318
319/*
320 *	getty_options	- this is cut from getty.c
321 *			- it scan getty cmd args
322 *			- modification is made to stuff args in pmtab
323 */
324static	void
325getty_options(argc, argv, pmtab)
326int argc;
327char **argv;
328struct	pmtab	*pmtab;
329{
330	char	*ptr;
331
332	/*
333	 * the pre-4.0 getty's hang_up_line() is a no-op.
334	 * For compatibility, H_FLAG cannot be set for this "getty".
335	 */
336	pmtab->p_ttyflags &= ~(H_FLAG);
337
338	while (--argc && **++argv == '-') {
339		for (ptr = *argv + 1; *ptr; ptr++)
340		switch (*ptr) {
341		case 'h':
342			break;
343		case 't':
344			if (isdigit(*++ptr)) {
345				(void) sscanf(ptr, "%d", &(pmtab->p_timeout));
346				while (isdigit(*++ptr));
347				ptr--;
348			} else if (--argc) {
349				if (isdigit(*(ptr = *++argv)))
350					(void) sscanf(ptr, "%d",
351					    &(pmtab->p_timeout));
352				else {
353					log("getty: timeout argument <%s> "
354					    "invalid", *argv);
355					exit(1);
356				}
357			}
358			break;
359
360		case 'c':
361			log("Use \"sttydefs -l\" to check /etc/ttydefs.");
362			exit(0);
363		default:
364			break;
365		}
366	}
367
368	if (argc < 1) {
369		log("getty: no terminal line specified.");
370		exit(1);
371	} else {
372		(void) strcat(devbuf, "/dev/");
373		(void) strcat(devbuf, *argv);
374		pmtab->p_device = devbuf;
375	}
376
377	if (--argc > 0) {
378		pmtab->p_ttylabel = *++argv;
379	}
380
381	/*
382	 * every thing after this will be ignored
383	 * i.e. termtype and linedisc are ignored
384	 */
385}
386
387/*
388 * find_ttyname(fd) 	- find the name of device associated with fd.
389 *			- it first tries utmpx to see if an entry exists
390 *			- with my pid and ut_line is defined. If ut_line
391 *			- is defined, it will see if the major and minor
392 *			- number of fd and devname from utmpx match.
393 *			- If utmpx search fails, ttyname(fd) will be called.
394 */
395static	char	*
396find_ttyname(fd)
397int	fd;
398{
399	pid_t ownpid;
400	struct utmpx *u;
401	static	struct	stat	statf, statu;
402	static	char	buf[BUFSIZ];
403
404	ownpid = getpid();
405	setutxent();
406	while ((u = getutxent()) != NULL) {
407		if (u->ut_pid == ownpid) {
408			if (strlen(u->ut_line) != 0) {
409				if (*(u->ut_line) != '/') {
410					(void) strcpy(buf, "/dev/");
411					(void) strncat(buf, u->ut_line,
412						sizeof (u->ut_line));
413				} else {
414					(void) strncat(buf, u->ut_line,
415					    sizeof (u->ut_line));
416				}
417			}
418			else
419				u = NULL;
420			break;
421		}
422	}
423	endutxent();
424	if ((u != NULL) &&
425		(fstat(fd, &statf) == 0) &&
426		(stat(buf, &statu) == 0) &&
427		(statf.st_dev == statu.st_dev) &&
428		(statf.st_rdev == statu.st_rdev)) {
429#ifdef	DEBUG
430			debug("ttymon_express: find device name from utmpx.");
431#endif
432			return (buf);
433	} else {
434#ifdef	DEBUG
435		debug("ttymon_express: calling ttyname to find device name.");
436#endif
437		return (ttyname(fd));
438	}
439}
440
441/*
442 * Revoke all access to a device node and make sure that there are
443 * no interposed streams devices attached.  Must be called before a
444 * device is actually opened.
445 * When fdetach is called, the underlying device node is revealed; it
446 * will have the previous owner and that owner can re-attach; so we
447 * retry until we win.
448 * Ignore non-existent devices.
449 */
450void
451revokedevaccess(char *dev, uid_t uid, gid_t gid, mode_t mode)
452{
453	do {
454		if (chown(dev, uid, gid) == -1)
455			return;
456	} while (fdetach(dev) == 0);
457
458	/* Remove ACLs */
459
460	(void) acl_strip(dev, uid, gid, mode);
461}
462