xref: /illumos-gate/usr/src/cmd/pwconv/pwconv.c (revision d583b39bfb4e2571d3e41097c5c357ffe353ad45)
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 2006 Sun Microsystems, Inc.  All rights reserved.
24  * Use is subject to license terms.
25  */
26 
27 /*	Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T	*/
28 /*	  All Rights Reserved  	*/
29 
30 #pragma ident	"%Z%%M%	%I%	%E% SMI"
31 
32 /*  pwconv.c  */
33 /*  Conversion aid to copy appropriate fields from the	*/
34 /*  password file to the shadow file.			*/
35 
36 #include <pwd.h>
37 #include <fcntl.h>
38 #include <stdio.h>
39 #include <sys/types.h>
40 #include <sys/stat.h>
41 #include <time.h>
42 #include <shadow.h>
43 #include <grp.h>
44 #include <signal.h>
45 #include <errno.h>
46 #include <unistd.h>
47 #include <stdlib.h>
48 #include <locale.h>
49 #include <string.h>
50 
51 #define	PRIVILEGED	0 			/* priviledged id */
52 
53 /* exit  code */
54 #define	SUCCESS	0	/* succeeded */
55 #define	NOPERM	1	/* No permission */
56 #define	BADSYN	2	/* Incorrect syntax */
57 #define	FMERR	3	/* File manipulation error */
58 #define	FATAL	4	/* Old file can not be recover */
59 #define	FBUSY	5	/* Lock file busy */
60 #define	BADSHW	6	/* Bad entry in shadow file  */
61 
62 #define	DELPTMP()	(void) unlink(PASSTEMP)
63 #define	DELSHWTMP()	(void) unlink(SHADTEMP)
64 
65 char pwdflr[]	= "x";				/* password filler */
66 char *prognamp;
67 void f_err(void), f_miss(void), f_bdshw(void);
68 
69 /*
70  * getspnan routine that ONLY looks at the local shadow file
71  */
72 struct spwd *
73 local_getspnam(char *name)
74 {
75 	FILE *shadf;
76 	struct spwd *sp;
77 
78 
79 	if ((shadf = fopen("/etc/shadow", "r")) == NULL)
80 		return (NULL);
81 
82 	while ((sp = fgetspent(shadf)) != NULL) {
83 		if (strcmp(sp->sp_namp, name) == 0)
84 			break;
85 	}
86 
87 	(void) fclose(shadf);
88 
89 	return (sp);
90 }
91 
92 int
93 main(int argc, char **argv)
94 {
95 	extern	int	errno;
96 	void  no_recover(void), no_convert(void);
97 	struct  passwd  *pwdp;
98 	struct	spwd	*sp, sp_pwd;		/* default entry */
99 	struct stat buf;
100 	FILE	*tp_fp, *tsp_fp;
101 	time_t	when, minweeks, maxweeks;
102 	int file_exist = 1;
103 	int end_of_file = 0;
104 	mode_t mode;
105 	mode_t pwd_mode;
106 	int pwerr = 0;
107 	ushort_t i;
108 	gid_t pwd_gid, sp_gid;
109 	uid_t pwd_uid, sp_uid;
110 	FILE *pwf;
111 	int black_magic = 0;
112 	int count;
113 
114 	(void) setlocale(LC_ALL, "");
115 
116 #if !defined(TEXT_DOMAIN)	/* Should be defined by cc -D */
117 #define	TEXT_DOMAIN "SYS_TEST"
118 #endif
119 	(void) textdomain(TEXT_DOMAIN);
120 
121 	prognamp = argv[0];
122 	/* only PRIVILEGED can execute this command */
123 	if (getuid() != PRIVILEGED) {
124 		(void) fprintf(stderr, gettext("%s: Permission denied.\n"),
125 		    prognamp);
126 		exit(NOPERM);
127 	}
128 
129 	/* No argument can be passed to the command */
130 	if (argc > 1) {
131 		(void) fprintf(stderr,
132 		gettext("%s: Invalid command syntax.\n"),
133 			prognamp);
134 		(void) fprintf(stderr, gettext("Usage: pwconv\n"));
135 		exit(BADSYN);
136 	}
137 
138 	/* lock file so that only one process can read or write at a time */
139 	if (lckpwdf() < 0) {
140 		(void) fprintf(stderr,
141 		gettext("%s: Password file(s) busy.  Try again later.\n"),
142 			prognamp);
143 		exit(FBUSY);
144 	}
145 
146 	/* All signals will be ignored during the execution of pwconv */
147 	for (i = 1; i < NSIG; i++)
148 		(void) sigset(i, SIG_IGN);
149 
150 	/* reset errno to avoid side effects of a failed */
151 	/* sigset (e.g., SIGKILL) */
152 	errno = 0;
153 
154 	/* check the file status of the password file */
155 	/* get the gid of the password file */
156 	if (stat(PASSWD, &buf) < 0) {
157 		(void) f_miss();
158 		exit(FATAL);
159 	}
160 	pwd_gid = buf.st_gid;
161 	pwd_uid = buf.st_uid;
162 	pwd_mode = buf.st_mode;
163 
164 	/* mode for the password file should be read-only or less */
165 	(void) umask(S_IAMB & ~(buf.st_mode & (S_IRUSR|S_IRGRP|S_IROTH)));
166 
167 	/* open temporary password file */
168 	if ((tp_fp = fopen(PASSTEMP, "w")) == NULL) {
169 		(void) f_err();
170 		exit(FMERR);
171 	}
172 
173 	if (chown(PASSTEMP, pwd_uid, pwd_gid) < 0) {
174 		DELPTMP();
175 		(void) f_err();
176 		exit(FMERR);
177 	}
178 	/* default mode mask of the shadow file */
179 	mode = S_IAMB & ~(S_IRUSR);
180 
181 	/* check the existence of  shadow file */
182 	/* if the shadow file exists, get mode mask and group id of the file */
183 	/* if file does not exist, the default group name will be the group  */
184 	/* name of the password file.  */
185 
186 	if (access(SHADOW, F_OK) == 0) {
187 		if (stat(SHADOW, &buf) == 0) {
188 			mode  = S_IAMB & ~(buf.st_mode & S_IRUSR);
189 			sp_gid = buf.st_gid;
190 			sp_uid = buf.st_uid;
191 		} else {
192 			DELPTMP();
193 			(void) f_err();
194 			exit(FMERR);
195 		}
196 	} else {
197 		sp_gid = pwd_gid;
198 		sp_uid = pwd_uid;
199 		file_exist = 0;
200 	}
201 	/*
202 	 * get the mode of shadow password file  -- mode of the file should
203 	 * be read-only for user or less.
204 	 */
205 	(void) umask(mode);
206 
207 	/* open temporary shadow file */
208 	if ((tsp_fp = fopen(SHADTEMP, "w")) == NULL) {
209 		DELPTMP();
210 		(void) f_err();
211 		exit(FMERR);
212 	}
213 
214 	/* change the group of the temporary shadow password file */
215 	if (chown(SHADTEMP, sp_uid, sp_gid) < 0) {
216 		(void) no_convert();
217 		exit(FMERR);
218 	}
219 
220 	/* Reads the password file.  				*/
221 	/* If the shadow password file not exists, or		*/
222 	/* if an entry doesn't have a corresponding entry in    */
223 	/* the shadow file, entries/entry will be created.	*/
224 
225 	if ((pwf = fopen("/etc/passwd", "r")) == NULL) {
226 		no_recover();
227 		exit(FATAL);
228 	}
229 
230 	count = 0;
231 	while (!end_of_file) {
232 		count++;
233 		if ((pwdp = fgetpwent(pwf)) != NULL) {
234 			if (!file_exist ||
235 			    (sp = local_getspnam(pwdp->pw_name)) == NULL) {
236 				if (errno == EINVAL) {
237 				/* Bad entry in shadow exit */
238 					DELSHWTMP();
239 					DELPTMP();
240 					(void) f_bdshw();
241 					exit(BADSHW);
242 				}
243 				sp = &sp_pwd;
244 				sp->sp_namp = pwdp->pw_name;
245 				if (!pwdp->pw_passwd ||
246 				    (pwdp->pw_passwd &&
247 					*pwdp->pw_passwd == NULL)) {
248 					(void) fprintf(stderr,
249 			gettext("%s: WARNING user %s has no password\n"),
250 					prognamp, sp->sp_namp);
251 				}
252 				/*
253 				 * copy the password field in the password
254 				 * file to the shadow file.
255 				 * replace the password field with an 'x'.
256 				 */
257 				sp->sp_pwdp = pwdp->pw_passwd;
258 				pwdp->pw_passwd = pwdflr;
259 				/*
260 				 * if aging, split the aging info
261 				 * into age, max and min
262 				 * convert aging info from weeks to days
263 				 */
264 				if (pwdp->pw_age && *pwdp->pw_age != NULL) {
265 					when = (long)a64l(pwdp->pw_age);
266 					maxweeks = when & 077;
267 					minweeks = (when >> 6) & 077;
268 					when >>= 12;
269 					sp->sp_lstchg = when * 7;
270 					sp->sp_min = minweeks * 7;
271 					sp->sp_max = maxweeks * 7;
272 					sp->sp_warn = -1;
273 					sp->sp_inact = -1;
274 					sp->sp_expire = -1;
275 					sp->sp_flag = 0;
276 					pwdp->pw_age = "";  /* do we care? */
277 				} else {
278 				/*
279 				 * if !aging, last_changed will be the day the
280 				 * conversion is done, min and max fields will
281 				 * be null - use timezone to get local time
282 				 */
283 					sp->sp_lstchg = DAY_NOW;
284 					sp->sp_min =  -1;
285 					sp->sp_max =  -1;
286 					sp->sp_warn = -1;
287 					sp->sp_inact = -1;
288 					sp->sp_expire = -1;
289 					sp->sp_flag = 0;
290 				}
291 	    } else {
292 			/*
293 			 * if the passwd field has a string other than 'x',
294 			 * the entry will be written into the shadow file
295 			 * and the character 'x' is re-written as the passwd
296 			 * if !aging, last_changed as above
297 			 */
298 
299 			/*
300 			 * with NIS, only warn about password missing if entry
301 			 * is not a NIS-lookup entry ("+" or "-")
302 			 * black_magic from getpwnam_r.c
303 			 */
304 			black_magic = (*pwdp->pw_name == '+' ||
305 					*pwdp->pw_name == '-');
306 			/*
307 			 * moan about absence of non "+/-" passwd
308 			 * we could do more, but what?
309 			 */
310 			if ((!pwdp->pw_passwd ||
311 			    (pwdp->pw_passwd && *pwdp->pw_passwd == NULL)) &&
312 			    !black_magic) {
313 				(void) fprintf(stderr,
314 			gettext("%s: WARNING user %s has no password\n"),
315 					prognamp, sp->sp_namp);
316 			}
317 			if (pwdp->pw_passwd && *pwdp->pw_passwd) {
318 				if (strcmp(pwdp->pw_passwd, pwdflr)) {
319 					sp->sp_pwdp = pwdp->pw_passwd;
320 					pwdp->pw_passwd = pwdflr;
321 					if (!pwdp->pw_age ||
322 					    (pwdp->pw_age &&
323 						*pwdp->pw_age == NULL)) {
324 						sp->sp_lstchg = DAY_NOW;
325 						sp->sp_min =  -1;
326 						sp->sp_max =  -1;
327 						sp->sp_warn = -1;
328 						sp->sp_inact = -1;
329 						sp->sp_expire = -1;
330 						sp->sp_flag = 0;
331 					}
332 				}
333 			} else {
334 				/*
335 				 * black_magic needs a non-null passwd
336 				 * and pwdflr seem appropriate here
337 				 * clear garbage if any
338 				 */
339 				sp->sp_pwdp = "";
340 				pwdp->pw_passwd = pwdflr;
341 				sp->sp_lstchg = sp->sp_min = sp->sp_max = -1;
342 				sp->sp_warn = sp->sp_inact = sp->sp_expire = -1;
343 				sp->sp_flag = 0;
344 			}
345 			/*
346 			 * if aging, split the aging info
347 			 * into age, max and min
348 			 * convert aging info from weeks to days
349 			 */
350 			if (pwdp->pw_age && *pwdp->pw_age != NULL) {
351 				when = (long)a64l(pwdp->pw_age);
352 				maxweeks = when & 077;
353 				minweeks = (when >> 6) & 077;
354 				when >>= 12;
355 				sp->sp_lstchg = when * 7;
356 				sp->sp_min = minweeks * 7;
357 				sp->sp_max = maxweeks * 7;
358 				sp->sp_warn = -1;
359 				sp->sp_inact = -1;
360 				sp->sp_expire = -1;
361 				sp->sp_flag = 0;
362 				pwdp->pw_age = ""; /* do we care? */
363 			}
364 		}
365 
366 		/* write an entry to temporary password file */
367 		if ((putpwent(pwdp, tp_fp)) != 0) {
368 			(void) no_convert();
369 			exit(FMERR);
370 		}
371 
372 		/* write an entry to temporary shadow password file */
373 		if (putspent(sp, tsp_fp) != 0) {
374 			(void) no_convert();
375 			exit(FMERR);
376 		}
377 	    } else {
378 		if (feof(pwf)) {
379 			end_of_file = 1;
380 		} else {
381 			errno = 0;
382 			pwerr = 1;
383 			(void) fprintf(stderr,
384 			    gettext("%s: ERROR: bad entry or blank "
385 			    "line at line %d in /etc/passwd\n"),
386 			    prognamp, count);
387 		}
388 	    }
389 	} /* end of while */
390 
391 	(void) fclose(pwf);
392 	(void) fclose(tsp_fp);
393 	(void) fclose(tp_fp);
394 	if (pwerr) {
395 		(void) no_convert();
396 		exit(FMERR);
397 	}
398 
399 	/* delete old password file if it exists */
400 	if (unlink(OPASSWD) && (access(OPASSWD, F_OK) == 0)) {
401 		(void) no_convert();
402 		exit(FMERR);
403 	}
404 
405 	/* rename the password file to old password file  */
406 	if (rename(PASSWD, OPASSWD) == -1) {
407 		(void) no_convert();
408 		exit(FMERR);
409 	}
410 
411 	/* rename temporary password file to password file */
412 	if (rename(PASSTEMP, PASSWD) == -1) {
413 		/* link old password file to password file */
414 		if (link(OPASSWD, PASSWD) < 0) {
415 			(void) no_recover();
416 			exit(FATAL);
417 		}
418 		(void) no_convert();
419 		exit(FMERR);
420 	}
421 
422 	/* delete old shadow password file if it exists */
423 	if (unlink(OSHADOW) && (access(OSHADOW, R_OK) == 0)) {
424 		/* link old password file to password file */
425 		if (unlink(PASSWD) || link(OPASSWD, PASSWD)) {
426 			(void) no_recover();
427 			exit(FATAL);
428 		}
429 		(void) no_convert();
430 		exit(FMERR);
431 	}
432 
433 	/* link shadow password file to old shadow password file */
434 	if (file_exist && rename(SHADOW, OSHADOW)) {
435 		/* link old password file to password file */
436 		if (unlink(PASSWD) || link(OPASSWD, PASSWD)) {
437 			(void) no_recover();
438 			exit(FATAL);
439 		}
440 		(void) no_convert();
441 		exit(FMERR);
442 	}
443 
444 
445 	/* link temporary shadow password file to shadow password file */
446 	if (rename(SHADTEMP, SHADOW) == -1) {
447 		/* link old shadow password file to shadow password file */
448 		if (file_exist && (link(OSHADOW, SHADOW))) {
449 			(void) no_recover();
450 			exit(FATAL);
451 		}
452 		if (unlink(PASSWD) || link(OPASSWD, PASSWD)) {
453 			(void) no_recover();
454 			exit(FATAL);
455 		}
456 		(void) no_convert();
457 		exit(FMERR);
458 	}
459 
460 	/* Make new mode same as old */
461 	(void) chmod(PASSWD, pwd_mode);
462 
463 	/* Change old password file to read only by owner   */
464 	/* If chmod fails, delete the old password file so that */
465 	/* the password fields can not be read by others */
466 	if (chmod(OPASSWD, S_IRUSR) < 0)
467 		(void) unlink(OPASSWD);
468 
469 	(void) ulckpwdf();
470 	return (0);
471 }
472 
473 void
474 no_recover(void)
475 {
476 	DELPTMP();
477 	DELSHWTMP();
478 	(void) f_miss();
479 }
480 
481 void
482 no_convert(void)
483 {
484 	DELPTMP();
485 	DELSHWTMP();
486 	(void) f_err();
487 }
488 
489 void
490 f_err(void)
491 {
492 	(void) fprintf(stderr,
493 		gettext("%s: Unexpected failure. Conversion not done.\n"),
494 			prognamp);
495 	(void) ulckpwdf();
496 }
497 
498 void
499 f_miss(void)
500 {
501 	(void) fprintf(stderr,
502 		gettext("%s: Unexpected failure. Password file(s) missing.\n"),
503 			prognamp);
504 	(void) ulckpwdf();
505 }
506 
507 void
508 f_bdshw(void)
509 {
510 	(void) fprintf(stderr,
511 		gettext("%s: Bad entry in /etc/shadow. Conversion not done.\n"),
512 			prognamp);
513 	(void) ulckpwdf();
514 }
515