1/*
2 * Copyright (c) 1999 Apple Computer, Inc. All rights reserved.
3 *
4 * @APPLE_LICENSE_HEADER_START@
5 *
6 * "Portions Copyright (c) 1999 Apple Computer, Inc.  All Rights
7 * Reserved.  This file contains Original Code and/or Modifications of
8 * Original Code as defined in and that are subject to the Apple Public
9 * Source License Version 1.0 (the 'License').  You may not use this file
10 * except in compliance with the License.  Please obtain a copy of the
11 * License at http://www.apple.com/publicsource and read it before using
12 * this file.
13 *
14 * The Original Code and all software distributed under the License are
15 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
16 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
17 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
18 * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT.  Please see the
19 * License for the specific language governing rights and limitations
20 * under the License."
21 *
22 * @APPLE_LICENSE_HEADER_END@
23 */
24/*	$NetBSD: passwd.c,v 1.11 1997/12/31 05:47:15 thorpej Exp $	*/
25
26/*
27 * Copyright (c) 1987, 1993, 1994, 1995
28 *	The Regents of the University of California.  All rights reserved.
29 *
30 * Redistribution and use in source and binary forms, with or without
31 * modification, are permitted provided that the following conditions
32 * are met:
33 * 1. Redistributions of source code must retain the above copyright
34 *    notice, this list of conditions and the following disclaimer.
35 * 2. Redistributions in binary form must reproduce the above copyright
36 *    notice, this list of conditions and the following disclaimer in the
37 *    documentation and/or other materials provided with the distribution.
38 * 3. All advertising materials mentioning features or use of this software
39 *    must display the following acknowledgement:
40 *	This product includes software developed by the University of
41 *	California, Berkeley and its contributors.
42 * 4. Neither the name of the University nor the names of its contributors
43 *    may be used to endorse or promote products derived from this software
44 *    without specific prior written permission.
45 *
46 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
47 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
48 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
49 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
50 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
51 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
52 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
53 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
54 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
55 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
56 * SUCH DAMAGE.
57 */
58
59#include <sys/cdefs.h>
60#if defined(LIBC_SCCS) && !defined(lint)
61__RCSID("$NetBSD: passwd.c,v 1.11 1997/12/31 05:47:15 thorpej Exp $");
62#endif /* LIBC_SCCS and not lint */
63
64#include <sys/types.h>
65#include <sys/stat.h>
66#include <sys/time.h>
67#include <sys/resource.h>
68#include <sys/wait.h>
69
70#include <ctype.h>
71#include <err.h>
72#include <fcntl.h>
73#include <unistd.h>
74#include <stdlib.h>
75#include <stdio.h>
76#include <string.h>
77#include <pwd.h>
78#include <errno.h>
79#include <paths.h>
80#include <signal.h>
81#include <limits.h>
82#include <util.h>
83
84static void	pw_cont __P((int sig));
85static int	pw_equal __P((char *buf, struct passwd *old_pw));
86void		pw_error __P((const char *, int, int)) __dead2;
87int		pw_scan __P((char *, struct passwd *, int *));
88
89int
90pw_lock(retries)
91	int retries;
92{
93	int i, fd;
94	mode_t old_mode;
95
96	/* Acquire the lock file. */
97	old_mode = umask(0);
98	fd = open(_PATH_MASTERPASSWD_LOCK, O_WRONLY|O_CREAT|O_EXCL, 0600);
99	for (i = 0; i < retries && fd < 0 && errno == EEXIST; i++) {
100		sleep(1);
101		fd = open(_PATH_MASTERPASSWD_LOCK, O_WRONLY|O_CREAT|O_EXCL,
102			  0600);
103	}
104	umask(old_mode);
105	return(fd);
106}
107
108int
109pw_mkdb()
110{
111	int pstat;
112	pid_t pid;
113	struct stat sb;
114
115	/* A zero length passwd file is never ok */
116	if (stat(_PATH_MASTERPASSWD_LOCK, &sb) == 0) {
117		if (sb.st_size == 0) {
118			warnx("%s is zero length", _PATH_MASTERPASSWD_LOCK);
119			return (-1);
120		}
121	}
122
123	pid = vfork();
124	if (pid == 0) {
125		execl(_PATH_PWD_MKDB, "pwd_mkdb", "-p",
126		      _PATH_MASTERPASSWD_LOCK, NULL);
127		_exit(1);
128	}
129	pid = waitpid(pid, &pstat, 0);
130	if (pid == -1 || !WIFEXITED(pstat) || WEXITSTATUS(pstat) != 0)
131		return(-1);
132	return(0);
133}
134
135int
136pw_abort()
137{
138	return(unlink(_PATH_MASTERPASSWD_LOCK));
139}
140
141/* Everything below this point is intended for the convenience of programs
142 * which allow a user to interactively edit the passwd file.  Errors in the
143 * routines below will cause the process to abort. */
144
145static pid_t editpid = -1;
146
147static void
148pw_cont(sig)
149	int sig;
150{
151
152	if (editpid != -1)
153		kill(editpid, sig);
154}
155
156void
157pw_init()
158{
159	struct rlimit rlim;
160
161	/* Unlimited resource limits. */
162	rlim.rlim_cur = rlim.rlim_max = RLIM_INFINITY;
163	(void)setrlimit(RLIMIT_CPU, &rlim);
164	(void)setrlimit(RLIMIT_FSIZE, &rlim);
165	(void)setrlimit(RLIMIT_STACK, &rlim);
166	(void)setrlimit(RLIMIT_DATA, &rlim);
167	(void)setrlimit(RLIMIT_RSS, &rlim);
168
169	/* Don't drop core (not really necessary, but GP's). */
170	rlim.rlim_cur = rlim.rlim_max = 0;
171	(void)setrlimit(RLIMIT_CORE, &rlim);
172
173	/* Turn off signals. */
174	(void)signal(SIGALRM, SIG_IGN);
175	(void)signal(SIGHUP, SIG_IGN);
176	(void)signal(SIGINT, SIG_IGN);
177	(void)signal(SIGPIPE, SIG_IGN);
178	(void)signal(SIGQUIT, SIG_IGN);
179	(void)signal(SIGTERM, SIG_IGN);
180	(void)signal(SIGCONT, pw_cont);
181}
182
183void
184pw_edit(notsetuid, filename)
185	int notsetuid;
186	const char *filename;
187{
188	int i, xargc, pstat;
189	char *p, *editor;
190	char **xargv;
191#ifdef __GNUC__
192	(void) &editor;
193#endif
194
195	if (filename == NULL)
196		filename = _PATH_MASTERPASSWD_LOCK;
197	if ((editor = getenv("EDITOR")) == NULL)
198		editor = strdup(_PATH_VI);
199	else
200		editor = strdup(editor);
201	if ((p = strrchr(editor, '/')))
202		++p;
203	else
204		p = editor;
205
206	/* Scan editor string, count spaces, allocate arg vector. */
207	for (i = 0, xargc = 0; p[i] != '\0'; i++) {
208		if (isspace(p[i])) {
209			while (isspace(p[i++]))
210				/* skip white space */ ;
211			if (p[i] == '\0')
212				break;
213			xargc++;
214		}
215	}
216
217	/* argv[0] + <xargc args> + filename + NULL */
218	xargv = (char **)malloc(sizeof(char *) * (xargc + 3));
219	if (xargv == NULL)
220		pw_error("malloc failed", 1, 1);
221
222	i = 0;
223	xargv[i++] = p;
224	for (; *p != '\0'; p++) {
225		if (isspace(*p)) {
226			while(isspace(*p))
227				*p++ = '\0';	/* blast whitespace */
228			if (*p == '\0')
229				break;
230			xargv[i++] = p;
231		}
232	}
233
234	xargv[i++] = (char *)filename;
235	xargv[i] = NULL;
236
237	if (!(editpid = vfork())) {
238		if (notsetuid) {
239			setgid(getgid());
240			setuid(getuid());
241		}
242		execvp(editor, xargv);
243		_exit(1);
244	}
245	for (;;) {
246		editpid = waitpid(editpid, (int *)&pstat, WUNTRACED);
247		if (editpid == -1)
248			pw_error(editor, 1, 1);
249		else if (WIFSTOPPED(pstat))
250			raise(WSTOPSIG(pstat));
251		else if (WIFEXITED(pstat) && WEXITSTATUS(pstat) == 0)
252			break;
253		else
254			pw_error(editor, 1, 1);
255	}
256	editpid = -1;
257	free(editor);
258	free(xargv);
259}
260
261void
262pw_prompt()
263{
264	int c;
265
266	(void)printf("re-edit the password file? [y]: ");
267	(void)fflush(stdout);
268	c = getchar();
269	if (c != EOF && c != '\n')
270		while (getchar() != '\n');
271	if (c == 'n')
272		pw_error(NULL, 0, 0);
273}
274
275/* for use in pw_copy(). Compare a pw entry to a pw struct. */
276static int
277pw_equal (buf, pw)
278	char *buf;
279	struct passwd *pw;
280{
281	struct passwd buf_pw;
282	int len = strlen (buf);
283	if (buf[len-1] == '\n')
284		buf[len-1] = '\0';
285	if (!pw_scan(buf, &buf_pw, NULL))
286		return 0;
287	return !strcmp(pw->pw_name, buf_pw.pw_name)
288		&& pw->pw_uid == buf_pw.pw_uid
289		&& pw->pw_gid == buf_pw.pw_gid
290		&& !strcmp(pw->pw_class, buf_pw.pw_class)
291		&& (long)pw->pw_change == (long)buf_pw.pw_change
292		&& (long)pw->pw_expire == (long)buf_pw.pw_expire
293		&& !strcmp(pw->pw_gecos, buf_pw.pw_gecos)
294		&& !strcmp(pw->pw_dir, buf_pw.pw_dir)
295		&& !strcmp(pw->pw_shell, buf_pw.pw_shell);
296}
297
298void
299pw_copy(ffd, tfd, pw, old_pw)
300	int ffd, tfd;
301	struct passwd *pw, *old_pw;
302{
303	FILE *from, *to;
304	int done;
305	char *p, buf[8192];
306
307	if (!(from = fdopen(ffd, "r")))
308		pw_error(_PATH_MASTERPASSWD, 1, 1);
309	if (!(to = fdopen(tfd, "w")))
310		pw_error(_PATH_MASTERPASSWD_LOCK, 1, 1);
311
312	for (done = 0; fgets(buf, sizeof(buf), from);) {
313		if (!strchr(buf, '\n')) {
314			warnx("%s: line too long", _PATH_MASTERPASSWD);
315			pw_error(NULL, 0, 1);
316		}
317		if (done) {
318			(void)fprintf(to, "%s", buf);
319			if (ferror(to))
320				goto err;
321			continue;
322		}
323		if (buf[0] == '#') {
324			/* skip comments for Rhapsody. */
325			continue;
326		}
327		if (!(p = strchr(buf, ':'))) {
328			warnx("%s: corrupted entry", _PATH_MASTERPASSWD);
329			pw_error(NULL, 0, 1);
330		}
331		*p = '\0';
332		if (strcmp(buf, pw->pw_name)) {
333			*p = ':';
334			(void)fprintf(to, "%s", buf);
335			if (ferror(to))
336				goto err;
337			continue;
338		}
339		*p = ':';
340		if (old_pw && !pw_equal(buf, old_pw)) {
341			warnx("%s: entry inconsistent",
342			      _PATH_MASTERPASSWD);
343			pw_error(NULL, 0, 1);
344		}
345		(void)fprintf(to, "%s:%s:%d:%d:%s:%ld:%ld:%s:%s:%s\n",
346		    pw->pw_name, pw->pw_passwd, pw->pw_uid, pw->pw_gid,
347		    pw->pw_class, (long)pw->pw_change, (long)pw->pw_expire,
348		    pw->pw_gecos, pw->pw_dir, pw->pw_shell);
349		done = 1;
350		if (ferror(to))
351			goto err;
352	}
353	/* Only append a new entry if real uid is root! */
354	if (!done) {
355		if (getuid() == 0) {
356			(void)fprintf(to, "%s:%s:%d:%d:%s:%ld:%ld:%s:%s:%s\n",
357			    pw->pw_name, pw->pw_passwd, pw->pw_uid, pw->pw_gid,
358			    pw->pw_class, (long)pw->pw_change,
359			    (long)pw->pw_expire, pw->pw_gecos, pw->pw_dir,
360			    pw->pw_shell);
361		} else {
362			warnx("%s: changes not made, no such entry",
363		      	    _PATH_MASTERPASSWD);
364		}
365	}
366
367	if (ferror(to))
368err:		pw_error(NULL, 1, 1);
369	(void)fclose(to);
370}
371
372int
373pw_scan(bp, pw, flags)
374	char *bp;
375	struct passwd *pw;
376	int *flags;
377{
378	unsigned long id;
379	int root;
380	char *p, *sh, *ep;
381
382	if (flags != (int *)NULL)
383		*flags = 0;
384
385	if (!(pw->pw_name = strsep(&bp, ":")))		/* login */
386		goto fmt;
387	root = !strcmp(pw->pw_name, "root");
388
389	if (!(pw->pw_passwd = strsep(&bp, ":")))	/* passwd */
390		goto fmt;
391
392	if (!(p = strsep(&bp, ":")))			/* uid */
393		goto fmt;
394	id = strtoul(p, &ep, 10);
395	if (root && id) {
396		warnx("root uid should be 0");
397		return (0);
398	}
399	if (id > UID_MAX || *ep != '\0') {
400		warnx("invalid uid '%s'", p);
401		return (0);
402	}
403	pw->pw_uid = (uid_t)id;
404	if ((*p == '\0') && (flags != (int *)NULL))
405		*flags |= _PASSWORD_NOUID;
406
407	if (!(p = strsep(&bp, ":")))			/* gid */
408		goto fmt;
409	id = strtoul(p, &ep, 10);
410	if (id > GID_MAX || *ep != '\0') {
411		warnx("invalid gid '%s'", p);
412		return (0);
413	}
414	pw->pw_gid = (gid_t)id;
415	if ((*p == '\0') && (flags != (int *)NULL))
416		*flags |= _PASSWORD_NOGID;
417
418	pw->pw_class = strsep(&bp, ":");		/* class */
419	if (!(p = strsep(&bp, ":")))			/* change */
420		goto fmt;
421	pw->pw_change = atol(p);
422	if ((*p == '\0') && (flags != (int *)NULL))
423		*flags |= _PASSWORD_NOCHG;
424	if (!(p = strsep(&bp, ":")))			/* expire */
425		goto fmt;
426	pw->pw_expire = atol(p);
427	if ((*p == '\0') && (flags != (int *)NULL))
428		*flags |= _PASSWORD_NOEXP;
429	pw->pw_gecos = strsep(&bp, ":");		/* gecos */
430	pw->pw_dir = strsep(&bp, ":");			/* directory */
431	if (!(pw->pw_shell = strsep(&bp, ":")))		/* shell */
432		goto fmt;
433
434	p = pw->pw_shell;
435	if (root && *p)					/* empty == /bin/sh */
436		for (setusershell();;) {
437			if (!(sh = getusershell())) {
438				warnx("warning, unknown root shell");
439				break;
440			}
441			if (!strcmp(p, sh))
442				break;
443		}
444
445	if ((p = strsep(&bp, ":"))) {			/* too many */
446fmt:		warnx("corrupted entry");
447		return (0);
448	}
449
450	return (1);
451}
452
453void
454pw_error(name, err, eval)
455	const char *name;
456	int err, eval;
457{
458	if (err)
459		warn("%s", name);
460
461	warnx("%s: unchanged", _PATH_MASTERPASSWD);
462	pw_abort();
463	exit(eval);
464}
465
466