xref: /minix/usr.bin/passwd/passwd.c (revision 4684ddb6)
1 /*	$NetBSD: passwd.c,v 1.30 2009/04/17 20:25:08 dyoung Exp $	*/
2 
3 /*
4  * Copyright (c) 1988, 1993, 1994
5  *	The Regents of the University of California.  All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. Neither the name of the University nor the names of its contributors
16  *    may be used to endorse or promote products derived from this software
17  *    without specific prior written permission.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29  * SUCH DAMAGE.
30  */
31 
32 #include <sys/cdefs.h>
33 #ifndef lint
34 __COPYRIGHT("@(#) Copyright (c) 1988, 1993, 1994\
35  The Regents of the University of California.  All rights reserved.");
36 #endif /* not lint */
37 
38 #ifndef lint
39 #if 0
40 static char sccsid[] = "from: @(#)passwd.c    8.3 (Berkeley) 4/2/94";
41 #else
42 __RCSID("$NetBSD: passwd.c,v 1.30 2009/04/17 20:25:08 dyoung Exp $");
43 #endif
44 #endif /* not lint */
45 
46 #include <assert.h>
47 #include <err.h>
48 #include <stdio.h>
49 #include <stdlib.h>
50 #include <string.h>
51 #include <unistd.h>
52 #include <pwd.h>
53 
54 #include "extern.h"
55 
56 #ifdef USE_PAM
57 
58 static void global_usage(const char *);
59 
60 static const struct pw_module_s {
61 	const char *argv0;
62 	const char *dbname;
63 	char compat_opt;
64 	void (*pw_usage)(const char *);
65 	void (*pw_process)(const char *, int, char **);
66 } pw_modules[] = {
67 	/* "files" -- local password database */
68 	{ NULL, "files", 'l', pwlocal_usage, pwlocal_process },
69 #ifdef YP
70 	/* "nis" -- YP/NIS password database */
71 	{ NULL, "nis", 'y', pwyp_usage, pwyp_process },
72 	{ "yppasswd", NULL, 0, pwyp_argv0_usage, pwyp_process },
73 #endif
74 #ifdef KERBEROS5
75 	/* "krb5" -- Kerberos 5 password database */
76 	{ NULL, "krb5", 'k', pwkrb5_usage, pwkrb5_process },
77 	{ "kpasswd", NULL, 0, pwkrb5_argv0_usage, pwkrb5_process },
78 #endif
79 	/* default -- use whatever PAM decides */
80 	{ NULL, NULL, 0, NULL, pwpam_process },
81 
82 	{ NULL, NULL, 0, NULL, NULL }
83 };
84 
85 static const struct pw_module_s *personality;
86 
87 static void
global_usage(const char * prefix)88 global_usage(const char *prefix)
89 {
90 	const struct pw_module_s *pwm;
91 
92 	(void) fprintf(stderr, "%s %s [user]\n", prefix, getprogname());
93 	for (pwm = pw_modules; pwm->pw_process != NULL; pwm++) {
94 		if (pwm->argv0 == NULL && pwm->pw_usage != NULL)
95 			(*pwm->pw_usage)("      ");
96 	}
97 }
98 
99 void
usage(void)100 usage(void)
101 {
102 
103 	if (personality != NULL && personality->pw_usage != NULL)
104 		(*personality->pw_usage)("usage:");
105 	else
106 		global_usage("usage:");
107 	exit(1);
108 }
109 
110 int
main(int argc,char ** argv)111 main(int argc, char **argv)
112 {
113 	const struct pw_module_s *pwm;
114 	const char *username;
115 	int ch, i;
116 	char opts[16];
117 
118 	/* Build opts string from module compat_opts */
119 	i = 0;
120 	opts[i++] = 'd';
121 	opts[i++] = ':';
122 	for (pwm = pw_modules; pwm->pw_process != NULL; pwm++) {
123 		if (pwm->compat_opt != 0)
124 			opts[i++] = pwm->compat_opt;
125 	}
126 	opts[i++] = '\0';
127 
128 	/* First, look for personality based on argv[0]. */
129 	for (pwm = pw_modules; pwm->pw_process != NULL; pwm++) {
130 		if (pwm->argv0 != NULL &&
131 		    strcmp(pwm->argv0, getprogname()) == 0)
132 			goto got_personality;
133 	}
134 
135 	/* Try based on compat_opt or -d. */
136 	for (ch = 0, pwm = pw_modules; pwm->pw_process != NULL; pwm++) {
137 		if (pwm->argv0 == NULL && pwm->dbname == NULL &&
138 		    pwm->compat_opt == 0) {
139 			/*
140 			 * We have reached the default personality case.
141 			 * Make sure the user didn't provide a bogus
142 			 * personality name.
143 			 */
144 			if (ch == 'd')
145 				usage();
146 			break;
147 		}
148 
149 		ch = getopt(argc, argv, opts);
150 		if (ch == '?')
151 			usage();
152 
153 		if (ch == 'd' && pwm->dbname != NULL &&
154 		    strcmp(pwm->dbname, optarg) == 0) {
155 			/*
156 			 * "passwd -d dbname" matches; this is our
157 			 * chosen personality.
158 			 */
159 			break;
160 		}
161 
162 		if (pwm->compat_opt != 0 && ch == pwm->compat_opt) {
163 			/*
164 			 * Legacy "passwd -l" or similar matches; this
165 			 * is our chosen personality.
166 			 */
167 			break;
168 		}
169 
170 		/* Reset getopt() and go around again. */
171 		optind = 1;
172 		optreset = 1;
173 	}
174 
175  got_personality:
176 	personality = pwm;
177 
178 	/*
179 	 * At this point, optind should be either 1 ("passwd"),
180 	 * 2 ("passwd -l"), or 3 ("passwd -d files").  Consume
181 	 * these arguments and reset getopt() for the modules to use.
182 	 */
183 	assert(optind >= 1 && optind <= 3);
184 	argc -= optind;
185 	argv += optind;
186 	optind = 0;
187 	optreset = 1;
188 
189 	username = getlogin();
190 	if (username == NULL)
191 		errx(1, "who are you ??");
192 
193 	(*personality->pw_process)(username, argc, argv);
194 	return 0;
195 }
196 
197 #else /* ! USE_PAM */
198 
199 static struct pw_module_s {
200 	const char *argv0;
201 	const char *args;
202 	const char *usage;
203 	int (*pw_init) __P((const char *));
204 	int (*pw_arg) __P((char, const char *));
205 	int (*pw_arg_end) __P((void));
206 	void (*pw_end) __P((void));
207 
208 	int (*pw_chpw) __P((const char*));
209 	int invalid;
210 #define	INIT_INVALID 1
211 #define ARG_INVALID 2
212 	int use_class;
213 } pw_modules[] = {
214 #ifdef KERBEROS5
215 	{ NULL, "5ku:", "[-5] [-k] [-u principal]",
216 	    krb5_init, krb5_arg, krb5_arg_end, krb5_end, krb5_chpw, 0, 0 },
217 	{ "kpasswd", "5ku:", "[-5] [-k] [-u principal]",
218 	    krb5_init, krb5_arg, krb5_arg_end, krb5_end, krb5_chpw, 0, 0 },
219 #endif
220 #ifdef YP
221 	{ NULL, "y", "[-y]",
222 	    yp_init, yp_arg, yp_arg_end, yp_end, yp_chpw, 0, 0 },
223 	{ "yppasswd", "", "[-y]",
224 	    yp_init, yp_arg, yp_arg_end, yp_end, yp_chpw, 0, 0 },
225 #endif
226 	/* local */
227 	{ NULL, "l", "[-l]",
228 	    local_init, local_arg, local_arg_end, local_end, local_chpw, 0, 0 },
229 
230 	/* terminator */
231 	{ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 }
232 };
233 
234 #if defined(__minix)
235 static __dead void
236 #else
237 static void
238 #endif /* defined(__minix) */
usage(void)239 usage(void)
240 {
241 	int i;
242 
243 	fprintf(stderr, "usage:\n");
244 	for (i = 0; pw_modules[i].pw_init != NULL; i++)
245 		if (! (pw_modules[i].invalid & INIT_INVALID))
246 			fprintf(stderr, "\t%s %s [user]\n", getprogname(),
247 			    pw_modules[i].usage);
248 	exit(1);
249 }
250 
251 int
main(int argc,char ** argv)252 main(int argc, char **argv)
253 {
254 	int ch;
255 	char *username;
256 	char optstring[64];  /* if we ever get more than 64 args, shoot me. */
257 	const char *curopt, *oopt;
258 	int i, j;
259 	int valid;
260 	int use_always;
261 
262 	/* allow passwd modules to do argv[0] specific processing */
263 	use_always = 0;
264 	valid = 0;
265 	for (i = 0; pw_modules[i].pw_init != NULL; i++) {
266 		pw_modules[i].invalid = 0;
267 		if (pw_modules[i].argv0) {
268 			/*
269 			 * If we have a module that matches this progname, be
270 			 * sure that no modules but those that match this
271 			 * progname can be used.  If we have a module that
272 			 * matches against a particular progname, but does NOT
273 			 * match this one, don't use that module.
274 			 */
275 			if ((strcmp(getprogname(), pw_modules[i].argv0) == 0) &&
276 			    use_always == 0) {
277 				for (j = 0; j < i; j++) {
278 					pw_modules[j].invalid |= INIT_INVALID;
279 					(*pw_modules[j].pw_end)();
280 				}
281 				use_always = 1;
282 			} else if (use_always == 0)
283 				pw_modules[i].invalid |= INIT_INVALID;
284 		} else if (use_always)
285 			pw_modules[i].invalid |= INIT_INVALID;
286 
287 		if (pw_modules[i].invalid)
288 			continue;
289 
290 		pw_modules[i].invalid |=
291 		    (*pw_modules[i].pw_init)(getprogname()) ?
292 		    /* zero on success, non-zero on error */
293 		    INIT_INVALID : 0;
294 
295 		if (! pw_modules[i].invalid)
296 			valid = 1;
297 	}
298 
299 	if (valid == 0)
300 		errx(1, "Can't change password.");
301 
302 	/* Build the option string from the individual modules' option
303 	 * strings.  Note that two modules can share a single option
304 	 * letter. */
305 	optstring[0] = '\0';
306 	j = 0;
307 	for (i = 0; pw_modules[i].pw_init != NULL; i++) {
308 		if (pw_modules[i].invalid)
309 			continue;
310 
311 		curopt = pw_modules[i].args;
312 		while (*curopt != '\0') {
313 			if ((oopt = strchr(optstring, *curopt)) == NULL) {
314 				optstring[j++] = *curopt;
315 				if (curopt[1] == ':') {
316 					curopt++;
317 					optstring[j++] = *curopt;
318 				}
319 				optstring[j] = '\0';
320 			} else if ((oopt[1] == ':' && curopt[1] != ':') ||
321 			    (oopt[1] != ':' && curopt[1] == ':')) {
322 				errx(1, "NetBSD ERROR!  Different password "
323 				    "modules have two different ideas about "
324 				    "%c argument format.", curopt[0]);
325 			}
326 			curopt++;
327 		}
328 	}
329 
330 	while ((ch = getopt(argc, argv, optstring)) != -1)
331 	{
332 		valid = 0;
333 		for (i = 0; pw_modules[i].pw_init != NULL; i++) {
334 			if (pw_modules[i].invalid)
335 				continue;
336 			if ((oopt = strchr(pw_modules[i].args, ch)) != NULL) {
337 				j = (oopt[1] == ':') ?
338 				    ! (*pw_modules[i].pw_arg)(ch, optarg) :
339 				    ! (*pw_modules[i].pw_arg)(ch, NULL);
340 				if (j != 0)
341 					pw_modules[i].invalid |= ARG_INVALID;
342 				if (pw_modules[i].invalid)
343 					(*pw_modules[i].pw_end)();
344 			} else {
345 				/* arg doesn't match this module */
346 				pw_modules[i].invalid |= ARG_INVALID;
347 				(*pw_modules[i].pw_end)();
348 			}
349 			if (! pw_modules[i].invalid)
350 				valid = 1;
351 		}
352 		if (! valid) {
353 			usage();
354 			exit(1);
355 		}
356 	}
357 
358 	/* select which module to use to actually change the password. */
359 	use_always = 0;
360 	valid = 0;
361 	for (i = 0; pw_modules[i].pw_init != NULL; i++)
362 		if (! pw_modules[i].invalid) {
363 			pw_modules[i].use_class = (*pw_modules[i].pw_arg_end)();
364 			if (pw_modules[i].use_class != PW_DONT_USE)
365 				valid = 1;
366 			if (pw_modules[i].use_class == PW_USE_FORCE)
367 				use_always = 1;
368 		}
369 
370 
371 	if (! valid)
372 		/* hang the DJ */
373 		errx(1, "No valid password module specified.");
374 
375 	argc -= optind;
376 	argv += optind;
377 
378 	username = getlogin();
379 	if (username == NULL)
380 		errx(1, "who are you ??");
381 
382 	switch(argc) {
383 	case 0:
384 		break;
385 	case 1:
386 		username = argv[0];
387 		break;
388 	default:
389 		usage();
390 		exit(1);
391 	}
392 
393 	/* allow for fallback to other chpw() methods. */
394 	for (i = 0; pw_modules[i].pw_init != NULL; i++) {
395 		if (pw_modules[i].invalid)
396 			continue;
397 		if ((use_always && pw_modules[i].use_class == PW_USE_FORCE) ||
398 		    (!use_always && pw_modules[i].use_class == PW_USE)) {
399 			valid = (*pw_modules[i].pw_chpw)(username);
400 			(*pw_modules[i].pw_end)();
401 			if (valid >= 0)
402 				exit(valid);
403 			/* return value < 0 indicates continuation. */
404 		}
405 	}
406 	exit(1);
407 }
408 
409 #endif /* USE_PAM */
410