1 /*-
2  * SPDX-License-Identifier: BSD-4-Clause
3  *
4  * Copyright (c) 1995, 1996
5  *	Bill Paul <wpaul@ctr.columbia.edu>.  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. All advertising materials mentioning features or use of this software
16  *    must display the following acknowledgement:
17  *	This product includes software developed by Bill Paul.
18  * 4. Neither the name of the author nor the names of any co-contributors
19  *    may be used to endorse or promote products derived from this software
20  *    without specific prior written permission.
21  *
22  * THIS SOFTWARE IS PROVIDED BY Bill Paul AND CONTRIBUTORS ``AS IS'' AND
23  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25  * ARE DISCLAIMED.  IN NO EVENT SHALL Bill Paul OR CONTRIBUTORS BE LIABLE
26  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32  * SUCH DAMAGE.
33  */
34 
35 #include <sys/cdefs.h>
36 __FBSDID("$FreeBSD$");
37 
38 #include <sys/param.h>
39 #include <sys/fcntl.h>
40 #include <sys/socket.h>
41 #include <sys/stat.h>
42 #include <sys/wait.h>
43 
44 #include <arpa/inet.h>
45 #include <netinet/in.h>
46 
47 #include <ctype.h>
48 #include <db.h>
49 #include <dirent.h>
50 #include <errno.h>
51 #include <limits.h>
52 #include <pwd.h>
53 #include <signal.h>
54 #include <stdio.h>
55 #include <stdlib.h>
56 #include <string.h>
57 #include <unistd.h>
58 
59 #include <libgen.h>
60 #include <libutil.h>
61 
62 #include <rpc/rpc.h>
63 #include <rpcsvc/yp.h>
64 struct dom_binding;
65 #include <rpcsvc/ypclnt.h>
66 #include "yppasswdd_extern.h"
67 #include "yppasswd.h"
68 #include "yppasswd_private.h"
69 #include "ypxfr_extern.h"
70 #include "yp_extern.h"
71 
72 static struct passwd yp_password;
73 
74 static void
75 xlate_passwd(struct x_master_passwd *xpwd, struct passwd *pwd)
76 {
77 	pwd->pw_name = xpwd->pw_name;
78 	pwd->pw_passwd = xpwd->pw_passwd;
79 	pwd->pw_uid = xpwd->pw_uid;
80 	pwd->pw_gid = xpwd->pw_gid;
81 	pwd->pw_change = xpwd->pw_change;
82 	pwd->pw_class = xpwd->pw_class;
83 	pwd->pw_gecos = xpwd->pw_gecos;
84 	pwd->pw_dir = xpwd->pw_dir;
85 	pwd->pw_shell = xpwd->pw_shell;
86 	pwd->pw_expire = xpwd->pw_expire;
87 	pwd->pw_fields = xpwd->pw_fields;
88 }
89 
90 static void
91 copy_yp_pass(char *p, int x, int m)
92 {
93 	char *t, *s = p;
94 	static char *buf;
95 
96 	yp_password.pw_fields = 0;
97 
98 	buf = realloc(buf, m + 10);
99 	bzero(buf, m + 10);
100 
101 	/* Turn all colons into NULLs */
102 	while (strchr(s, ':')) {
103 		s = (strchr(s, ':') + 1);
104 		*(s - 1)= '\0';
105 	}
106 
107 	t = buf;
108 #define EXPAND(e) do { \
109 	e = t; \
110 	while ((*t++ = *p++)); \
111 } while (0)
112         EXPAND(yp_password.pw_name);
113 	yp_password.pw_fields |= _PWF_NAME;
114         EXPAND(yp_password.pw_passwd);
115 	yp_password.pw_fields |= _PWF_PASSWD;
116 	yp_password.pw_uid = atoi(p);
117         p += (strlen(p) + 1);
118 	yp_password.pw_fields |= _PWF_UID;
119 	yp_password.pw_gid = atoi(p);
120         p += (strlen(p) + 1);
121 	yp_password.pw_fields |= _PWF_GID;
122 	if (x) {
123 		EXPAND(yp_password.pw_class);
124 		yp_password.pw_fields |= _PWF_CLASS;
125 		yp_password.pw_change = atol(p);
126 		p += (strlen(p) + 1);
127 		yp_password.pw_fields |= _PWF_CHANGE;
128 		yp_password.pw_expire = atol(p);
129 		p += (strlen(p) + 1);
130 		yp_password.pw_fields |= _PWF_EXPIRE;
131 	}
132         EXPAND(yp_password.pw_gecos);
133 	yp_password.pw_fields |= _PWF_GECOS;
134         EXPAND(yp_password.pw_dir);
135 	yp_password.pw_fields |= _PWF_DIR;
136         EXPAND(yp_password.pw_shell);
137 	yp_password.pw_fields |= _PWF_SHELL;
138 
139 	return;
140 }
141 
142 static int
143 validchars(char *arg)
144 {
145 	size_t i;
146 
147 	for (i = 0; i < strlen(arg); i++) {
148 		if (iscntrl(arg[i])) {
149 			yp_error("string contains a control character");
150 			return(1);
151 		}
152 		if (arg[i] == ':') {
153 			yp_error("string contains a colon");
154 			return(1);
155 		}
156 		/* Be evil: truncate strings with \n in them silently. */
157 		if (arg[i] == '\n') {
158 			arg[i] = '\0';
159 			return(0);
160 		}
161 	}
162 	return(0);
163 }
164 
165 static int
166 validate_master(struct passwd *opw __unused, struct x_master_passwd *npw)
167 {
168 
169 	if (npw->pw_name[0] == '+' || npw->pw_name[0] == '-') {
170 		yp_error("client tried to modify an NIS entry");
171 		return(1);
172 	}
173 
174 	if (validchars(npw->pw_shell)) {
175 		yp_error("specified shell contains invalid characters");
176 		return(1);
177 	}
178 
179 	if (validchars(npw->pw_gecos)) {
180 		yp_error("specified gecos field contains invalid characters");
181 		return(1);
182 	}
183 
184 	if (validchars(npw->pw_passwd)) {
185 		yp_error("specified password contains invalid characters");
186 		return(1);
187 	}
188 	return(0);
189 }
190 
191 static int
192 validate(struct passwd *opw, struct x_passwd *npw)
193 {
194 
195 	if (npw->pw_name[0] == '+' || npw->pw_name[0] == '-') {
196 		yp_error("client tried to modify an NIS entry");
197 		return(1);
198 	}
199 
200 	if ((uid_t)npw->pw_uid != opw->pw_uid) {
201 		yp_error("UID mismatch: client says user %s has UID %d",
202 			 npw->pw_name, npw->pw_uid);
203 		yp_error("database says user %s has UID %d", opw->pw_name,
204 			 opw->pw_uid);
205 		return(1);
206 	}
207 
208 	if ((gid_t)npw->pw_gid != opw->pw_gid) {
209 		yp_error("GID mismatch: client says user %s has GID %d",
210 			 npw->pw_name, npw->pw_gid);
211 		yp_error("database says user %s has GID %d", opw->pw_name,
212 			 opw->pw_gid);
213 		return(1);
214 	}
215 
216 	/*
217 	 * Don't allow the user to shoot himself in the foot,
218 	 * even on purpose.
219 	 */
220 	if (!no_chsh && !ok_shell(npw->pw_shell)) {
221 		yp_error("%s is not a valid shell", npw->pw_shell);
222 		return(1);
223 	}
224 
225 	if (!no_chsh && validchars(npw->pw_shell)) {
226 		yp_error("specified shell contains invalid characters");
227 		return(1);
228 	}
229 
230 	if (validchars(npw->pw_gecos)) {
231 		yp_error("specified gecos field contains invalid characters");
232 		return(1);
233 	}
234 
235 	if (validchars(npw->pw_passwd)) {
236 		yp_error("specified password contains invalid characters");
237 		return(1);
238 	}
239 	return(0);
240 }
241 
242 /*
243  * Kludge alert:
244  * In order to have one rpc.yppasswdd support multiple domains,
245  * we have to cheat: we search each directory under /var/yp
246  * and try to match the user in each master.passwd.byname
247  * map that we find. If the user matches (username, uid and gid
248  * all agree), then we use that domain. If we match the user in
249  * more than one database, we must abort.
250  */
251 static char *
252 find_domain(struct x_passwd *pw)
253 {
254 	struct stat statbuf;
255 	struct dirent *dirp;
256 	DIR *dird;
257 	char yp_mapdir[MAXPATHLEN + 2];
258 	static char domain[YPMAXDOMAIN];
259 	char *tmp = NULL;
260 	DBT key, data;
261 	int hit = 0;
262 
263 	yp_error("performing multidomain lookup");
264 
265 	if ((dird = opendir(yp_dir)) == NULL) {
266 		yp_error("opendir(%s) failed: %s", yp_dir, strerror(errno));
267 		return(NULL);
268 	}
269 
270 	while ((dirp = readdir(dird)) != NULL) {
271 		snprintf(yp_mapdir, sizeof yp_mapdir, "%s/%s",
272 							yp_dir, dirp->d_name);
273 		if (stat(yp_mapdir, &statbuf) < 0) {
274 			yp_error("stat(%s) failed: %s", yp_mapdir,
275 							strerror(errno));
276 			closedir(dird);
277 			return(NULL);
278 		}
279 		if (S_ISDIR(statbuf.st_mode)) {
280 			tmp = (char *)dirp->d_name;
281 			key.data = pw->pw_name;
282 			key.size = strlen(pw->pw_name);
283 
284 			if (yp_get_record(tmp,"master.passwd.byname",
285 			  		&key, &data, 0) != YP_TRUE) {
286 				continue;
287 			}
288 			*((char *)data.data + data.size) = '\0';
289 			copy_yp_pass(data.data, 1, data.size);
290 			if (yp_password.pw_uid == (uid_t)pw->pw_uid &&
291 			    yp_password.pw_gid == (gid_t)pw->pw_gid) {
292 				hit++;
293 				snprintf(domain, YPMAXDOMAIN, "%s", tmp);
294 			}
295 		}
296 	}
297 
298 	closedir(dird);
299 	if (hit > 1) {
300 		yp_error("found same user in two different domains");
301 		return(NULL);
302 	} else
303 		return((char *)&domain);
304 }
305 
306 static const char *maps[] = {
307 	"master.passwd.byname",
308 	"master.passwd.byuid",
309 	"passwd.byname",
310 	"passwd.byuid"
311 };
312 
313 static const char *formats[] = {
314 	"%s:%s:%d:%d:%s:%ld:%ld:%s:%s:%s",
315 	"%s:%s:%d:%d:%s:%ld:%ld:%s:%s:%s",
316 	"%s:%s:%d:%d:%s:%s:%s",
317 	"%s:%s:%d:%d:%s:%s:%s"
318 };
319 
320 static int
321 update_inplace(struct passwd *pw, char *domain)
322 {
323 	DB *dbp = NULL;
324 	DBT key = { NULL, 0 };
325 	DBT data = { NULL, 0 };
326 	char *pwbuf;
327 	char keybuf[20];
328 	int i;
329 	char *ptr = NULL;
330 	static char yp_last[] = "YP_LAST_MODIFIED";
331 	char yplastbuf[64];
332 
333 	snprintf(yplastbuf, sizeof yplastbuf, "%llu",
334 	    (unsigned long long)time(NULL));
335 	pwbuf = NULL;
336 
337 	for (i = 0; i < 4; i++) {
338 
339 		if (i % 2) {
340 			snprintf(keybuf, sizeof keybuf,
341 			    "%llu", (unsigned long long)pw->pw_uid);
342 			key.data = &keybuf;
343 			key.size = strlen(keybuf);
344 		} else {
345 			key.data = pw->pw_name;
346 			key.size = strlen(pw->pw_name);
347 		}
348 
349 		/*
350 		 * XXX The passwd.byname and passwd.byuid maps come in
351 		 * two flavors: secure and insecure. The secure version
352 		 * has a '*' in the password field whereas the insecure one
353 		 * has a real crypted password. The maps will be insecure
354 		 * if they were built with 'unsecure = TRUE' enabled in
355 		 * /var/yp/Makefile, but we'd have no way of knowing if
356 		 * this has been done unless we were to try parsing the
357 		 * Makefile, which is a disgusting thought. Instead, we
358 		 * read the records from the maps, skip to the first ':'
359 		 * in them, and then look at the character immediately
360 		 * following it. If it's an '*' then the map is 'secure'
361 		 * and we must not insert a real password into the pw_passwd
362 		 * field. If it's not an '*', then we put the real crypted
363 		 * password in.
364 		 */
365 		if (yp_get_record(domain,maps[i],&key,&data,1) != YP_TRUE) {
366 			yp_error("couldn't read %s/%s: %s", domain,
367 						maps[i], strerror(errno));
368 			goto ret1;
369 		}
370 
371 		if ((ptr = strchr(data.data, ':')) == NULL) {
372 			yp_error("no colon in passwd record?!");
373 			goto ret1;
374 		}
375 
376 		/*
377 		 * XXX Supposing we have more than one user with the same
378 		 * UID? (Or more than one user with the same name?) We could
379 		 * end up modifying the wrong record if were not careful.
380 		 */
381 		if (i % 2) {
382 			if (strncmp(data.data, pw->pw_name,
383 							strlen(pw->pw_name))) {
384 				yp_error("warning: found entry for UID %d \
385 in map %s@%s with wrong name (%.*s)", pw->pw_uid, maps[i], domain,
386 				    (int)(ptr - (char *)data.data),
387 				    (char *)data.data);
388 				yp_error("there may be more than one user \
389 with the same UID - continuing");
390 				continue;
391 			}
392 		} else {
393 			/*
394 			 * We're really being ultra-paranoid here.
395 			 * This is generally a 'can't happen' condition.
396 			 */
397 			free(pwbuf);
398 			asprintf(&pwbuf, ":%d:%d:", pw->pw_uid, pw->pw_gid);
399 			if (pwbuf == NULL) {
400 				yp_error("no memory");
401 				goto ret1;
402 			}
403 			if (!strstr(data.data, pwbuf)) {
404 				yp_error("warning: found entry for user %s \
405 in map %s@%s with wrong UID", pw->pw_name, maps[i], domain);
406 				yp_error("there may be more than one user \
407 with the same name - continuing");
408 				continue;
409 			}
410 		}
411 
412 		if (i < 2) {
413 			free(pwbuf);
414 			asprintf(&pwbuf, formats[i],
415 			   pw->pw_name, pw->pw_passwd, pw->pw_uid,
416 			   pw->pw_gid, pw->pw_class, pw->pw_change,
417 			   pw->pw_expire, pw->pw_gecos, pw->pw_dir,
418 			   pw->pw_shell);
419 		} else {
420 			free(pwbuf);
421 			asprintf(&pwbuf, formats[i],
422 			   pw->pw_name, *(ptr+1) == '*' ? "*" : pw->pw_passwd,
423 			   pw->pw_uid, pw->pw_gid, pw->pw_gecos, pw->pw_dir,
424 			   pw->pw_shell);
425 		}
426 		if (pwbuf == NULL) {
427 			yp_error("no memory");
428 			goto ret1;
429 		}
430 
431 #define FLAGS O_RDWR|O_CREAT
432 
433 		if ((dbp = yp_open_db_rw(domain, maps[i], FLAGS)) == NULL) {
434 			yp_error("couldn't open %s/%s r/w: %s",domain,
435 						maps[i],strerror(errno));
436 			goto ret1;
437 		}
438 
439 		data.data = pwbuf;
440 		data.size = strlen(pwbuf);
441 
442 		if (yp_put_record(dbp, &key, &data, 1) != YP_TRUE) {
443 			yp_error("failed to update record in %s/%s", domain,
444 								maps[i]);
445 			(void)(dbp->close)(dbp);
446 			goto ret1;
447 		}
448 
449 		key.data = yp_last;
450 		key.size = strlen(yp_last);
451 		data.data = (char *)&yplastbuf;
452 		data.size = strlen(yplastbuf);
453 
454 		if (yp_put_record(dbp, &key, &data, 1) != YP_TRUE) {
455 			yp_error("failed to update timestamp in %s/%s", domain,
456 								maps[i]);
457 			(void)(dbp->close)(dbp);
458 			goto ret1;
459 		}
460 
461 		(void)(dbp->close)(dbp);
462 	}
463 
464 	free(pwbuf);
465 	return (0);
466 ret1:
467 	free(pwbuf);
468 	return (1);
469 }
470 
471 int *
472 yppasswdproc_update_1_svc(yppasswd *argp, struct svc_req *rqstp)
473 {
474 	static int  result;
475 	struct sockaddr_in *rqhost;
476 	DBT key, data;
477 	int rval = 0;
478 	int pfd, tfd;
479 	int pid;
480 	int passwd_changed = 0;
481 	int shell_changed = 0;
482 	int gecos_changed = 0;
483 	char *cryptpw;
484 	char *oldshell = NULL;
485 	char *oldgecos = NULL;
486 	char *passdir;
487 	char *passfile_hold;
488 	char passdir_buf[MAXPATHLEN + 2];
489 	char passfile_buf[MAXPATHLEN + 2];
490 	char passfile_hold_buf[MAXPATHLEN + 2];
491 	char *domain = yppasswd_domain;
492 	static struct sockaddr_in clntaddr;
493 	static struct timeval t_saved, t_test;
494 
495 	/*
496 	 * Normal user updates always use the 'default' master.passwd file.
497 	 */
498 
499 	passfile = passfile_default;
500 	result = 1;
501 
502 	rqhost = svc_getcaller(rqstp->rq_xprt);
503 
504 	gettimeofday(&t_test, NULL);
505 	if (!bcmp(rqhost, &clntaddr, sizeof *rqhost) &&
506 		t_test.tv_sec > t_saved.tv_sec &&
507 		t_test.tv_sec - t_saved.tv_sec < 300) {
508 
509 		bzero(&clntaddr, sizeof clntaddr);
510 		bzero(&t_saved, sizeof t_saved);
511 		return(NULL);
512 	}
513 
514 	bcopy(rqhost, &clntaddr, sizeof clntaddr);
515 	gettimeofday(&t_saved, NULL);
516 
517 	if (yp_access(resvport ? "master.passwd.byname" : NULL, rqstp)) {
518 		yp_error("rejected update request from unauthorized host");
519 		svcerr_auth(rqstp->rq_xprt, AUTH_BADCRED);
520 		return(&result);
521 	}
522 
523 	/*
524 	 * Step one: find the user. (It's kinda pointless to
525 	 * proceed if the user doesn't exist.) We look for the
526 	 * user in the master.passwd.byname database, _NOT_ by
527 	 * using getpwent() and friends! We can't use getpwent()
528 	 * since the NIS master server is not guaranteed to be
529 	 * configured as an NIS client.
530 	 */
531 
532 	if (multidomain) {
533 		if ((domain = find_domain(&argp->newpw)) == NULL) {
534 			yp_error("multidomain lookup failed - aborting update");
535 			return(&result);
536 		} else
537 			yp_error("updating user %s in domain %s",
538 					argp->newpw.pw_name, domain);
539 	}
540 
541 	key.data = argp->newpw.pw_name;
542 	key.size = strlen(argp->newpw.pw_name);
543 
544 	if ((rval = yp_get_record(domain,"master.passwd.byname",
545 		  	&key, &data, 0)) != YP_TRUE) {
546 		if (rval == YP_NOKEY) {
547 			yp_error("user %s not found in passwd database",
548 			 	argp->newpw.pw_name);
549 		} else {
550 			yp_error("database access error: %s",
551 			 	yperr_string(rval));
552 		}
553 		return(&result);
554 	}
555 
556 	/* Nul terminate, please. */
557 	*((char *)data.data + data.size) = '\0';
558 
559 	copy_yp_pass(data.data, 1, data.size);
560 
561 	/* Step 2: check that the supplied oldpass is valid. */
562 
563 	cryptpw = crypt(argp->oldpass, yp_password.pw_passwd);
564 	if (cryptpw == NULL || strcmp(cryptpw, yp_password.pw_passwd)) {
565 		yp_error("rejected change attempt -- bad password");
566 		yp_error("client address: %s username: %s",
567 			  inet_ntoa(rqhost->sin_addr),
568 			  argp->newpw.pw_name);
569 		return(&result);
570 	}
571 
572 	/* Step 3: validate the arguments passed to us by the client. */
573 
574 	if (validate(&yp_password, &argp->newpw)) {
575 		yp_error("rejecting change attempt: bad arguments");
576 		yp_error("client address: %s username: %s",
577 			 inet_ntoa(rqhost->sin_addr),
578 			 argp->newpw.pw_name);
579 		svcerr_decode(rqstp->rq_xprt);
580 		return(&result);
581 	}
582 
583 	/* Step 4: update the user's passwd structure. */
584 
585 	if (!no_chsh && strcmp(argp->newpw.pw_shell, yp_password.pw_shell)) {
586 		oldshell = yp_password.pw_shell;
587 		yp_password.pw_shell = argp->newpw.pw_shell;
588 		shell_changed++;
589 	}
590 
591 
592 	if (!no_chfn && strcmp(argp->newpw.pw_gecos, yp_password.pw_gecos)) {
593 		oldgecos = yp_password.pw_gecos;
594 		yp_password.pw_gecos = argp->newpw.pw_gecos;
595 		gecos_changed++;
596 	}
597 
598 	if (strcmp(argp->newpw.pw_passwd, yp_password.pw_passwd)) {
599 		yp_password.pw_passwd = argp->newpw.pw_passwd;
600 		yp_password.pw_change = 0;
601 		passwd_changed++;
602 	}
603 
604 	/*
605 	 * If the caller specified a domain other than our 'default'
606 	 * domain, change the path to master.passwd accordingly.
607 	 */
608 
609 	if (strcmp(domain, yppasswd_domain)) {
610 		snprintf(passfile_buf, sizeof(passfile_buf),
611 			"%s/%s/master.passwd", yp_dir, domain);
612 		passfile = (char *)&passfile_buf;
613 	}
614 
615 	/*
616 	 * Create a filename to hold the original master.passwd
617 	 * so if our call to yppwupdate fails we can roll back
618 	 */
619 	snprintf(passfile_hold_buf, sizeof(passfile_hold_buf),
620 	    "%s.hold", passfile);
621 	passfile_hold = (char *)&passfile_hold_buf;
622 
623 
624 	/* Step 5: make a new password file with the updated info. */
625 
626 	snprintf(passdir_buf, sizeof(passdir_buf), "%s", passfile);
627 	passdir = dirname(passdir_buf);
628 
629 	if (pw_init(passdir, passfile)) {
630 		yp_error("pw_init() failed");
631 		return &result;
632 	}
633 	if ((pfd = pw_lock()) == -1) {
634 		pw_fini();
635 		yp_error("pw_lock() failed");
636 		return &result;
637 	}
638 	if ((tfd = pw_tmp(-1)) == -1) {
639 		pw_fini();
640 		yp_error("pw_tmp() failed");
641 		return &result;
642 	}
643 	if (pw_copy(pfd, tfd, &yp_password, NULL) == -1) {
644 		pw_fini();
645 		yp_error("pw_copy() failed");
646 		return &result;
647 	}
648 	if (rename(passfile, passfile_hold) == -1) {
649 		pw_fini();
650 		yp_error("rename of %s to %s failed", passfile,
651 		    passfile_hold);
652 		return &result;
653 	}
654 
655 	if (strcmp(passfile, _PATH_MASTERPASSWD) == 0) {
656 		/*
657 		 * NIS server is exporting the system's master.passwd.
658 		 * Call pw_mkdb to rebuild passwd and the .db files
659 		 */
660 		if (pw_mkdb(yp_password.pw_name) == -1) {
661 			pw_fini();
662 			yp_error("pw_mkdb() failed");
663 			rename(passfile_hold, passfile);
664 			return &result;
665 		}
666 	} else {
667 		/*
668 		 * NIS server is exporting a private master.passwd.
669 		 * Rename tempfile into final location
670 		 */
671 		if (rename(pw_tempname(), passfile) == -1) {
672 			pw_fini();
673 			yp_error("rename of %s to %s failed",
674 			    pw_tempname(), passfile);
675 			rename(passfile_hold, passfile);
676 			return &result;
677 		}
678 	}
679 
680 	pw_fini();
681 
682 	if (inplace) {
683 		if ((rval = update_inplace(&yp_password, domain))) {
684 			yp_error("inplace update failed -- rebuilding maps");
685 		}
686 	}
687 
688 	switch ((pid = fork())) {
689 	case 0:
690 		if (inplace && !rval) {
691     			execlp(MAP_UPDATE_PATH, MAP_UPDATE, passfile,
692 				yppasswd_domain, "pushpw", (char *)NULL);
693 		} else {
694     			execlp(MAP_UPDATE_PATH, MAP_UPDATE, passfile,
695 				yppasswd_domain, (char *)NULL);
696 		}
697     		yp_error("couldn't exec map update process: %s",
698 					strerror(errno));
699 		unlink(passfile);
700 		rename(passfile_hold, passfile);
701     		exit(1);
702 		break;
703 	case -1:
704 		yp_error("fork() failed: %s", strerror(errno));
705 		unlink(passfile);
706 		rename(passfile_hold, passfile);
707 		return(&result);
708 		break;
709 	default:
710 		unlink(passfile_hold);
711 		break;
712 	}
713 
714 	if (verbose) {
715 		yp_error("update completed for user %s (uid %d) in %s:",
716 		    argp->newpw.pw_name, argp->newpw.pw_uid, passfile);
717 
718 		if (passwd_changed)
719 			yp_error("password changed");
720 
721 		if (gecos_changed)
722 			yp_error("gecos changed ('%s' -> '%s')",
723 					oldgecos, argp->newpw.pw_gecos);
724 
725 		if (shell_changed)
726 			yp_error("shell changed ('%s' -> '%s')",
727 					oldshell, argp->newpw.pw_shell);
728 	}
729 
730 	result = 0;
731 	return (&result);
732 }
733 
734 /*
735  * Note that this function performs a little less sanity checking
736  * than the last one. Since only the superuser is allowed to use it,
737  * it is assumed that the caller knows what he's doing.
738  */
739 int *
740 yppasswdproc_update_master_1_svc(master_yppasswd *argp,
741     struct svc_req *rqstp)
742 {
743 	static int result;
744 	int pfd, tfd;
745 	int pid;
746 	uid_t uid;
747 	int rval = 0;
748 	DBT key, data;
749 	char *passdir;
750 	char *passfile_hold;
751 	char passdir_buf[MAXPATHLEN + 2];
752 	char passfile_buf[MAXPATHLEN + 2];
753 	char passfile_hold_buf[MAXPATHLEN + 2];
754 	struct sockaddr_in *rqhost;
755 	SVCXPRT	*transp;
756 	struct passwd newpasswd;
757 
758 	result = 1;
759 	transp = rqstp->rq_xprt;
760 
761 	/*
762 	 * NO AF_INET CONNETCIONS ALLOWED!
763 	 */
764 	rqhost = svc_getcaller(transp);
765 	if (rqhost->sin_family != AF_UNIX) {
766 		yp_error("Alert! %s/%d attempted to use superuser-only \
767 procedure!\n", inet_ntoa(rqhost->sin_addr), rqhost->sin_port);
768 		svcerr_auth(transp, AUTH_BADCRED);
769 		return(&result);
770 	}
771 
772 	if (rqstp->rq_cred.oa_flavor != AUTH_SYS) {
773 		yp_error("caller didn't send proper credentials");
774 		svcerr_auth(transp, AUTH_BADCRED);
775 		return(&result);
776 	}
777 
778 	if (__rpc_get_local_uid(transp, &uid) < 0) {
779 		yp_error("caller didn't send proper credentials");
780 		svcerr_auth(transp, AUTH_BADCRED);
781 		return(&result);
782 	}
783 
784 	if (uid) {
785 		yp_error("caller euid is %d, expecting 0 -- rejecting request",
786 		    uid);
787 		svcerr_auth(rqstp->rq_xprt, AUTH_BADCRED);
788 		return(&result);
789 	}
790 
791 	passfile = passfile_default;
792 
793 	key.data = argp->newpw.pw_name;
794 	key.size = strlen(argp->newpw.pw_name);
795 
796 	/*
797 	 * The superuser may add entries to the passwd maps if
798 	 * rpc.yppasswdd is started with the -a flag. Paranoia
799 	 * prevents me from allowing additions by default.
800 	 */
801 	if ((rval = yp_get_record(argp->domain, "master.passwd.byname",
802 			  &key, &data, 0)) != YP_TRUE) {
803 		if (rval == YP_NOKEY) {
804 			yp_error("user %s not found in passwd database",
805 				 argp->newpw.pw_name);
806 			if (allow_additions)
807 				yp_error("notice: adding user %s to \
808 master.passwd database for domain %s", argp->newpw.pw_name, argp->domain);
809 			else
810 				yp_error("restart rpc.yppasswdd with the -a flag to \
811 allow additions to be made to the password database");
812 		} else {
813 			yp_error("database access error: %s",
814 				 yperr_string(rval));
815 		}
816 		if (!allow_additions)
817 			return(&result);
818 	} else {
819 
820 		/* Nul terminate, please. */
821 		*((char *)data.data + data.size) = '\0';
822 
823 		copy_yp_pass(data.data, 1, data.size);
824 	}
825 
826 	/*
827 	 * Perform a small bit of sanity checking.
828 	 */
829 	if (validate_master(rval == YP_TRUE ? &yp_password:NULL,&argp->newpw)){
830 		yp_error("rejecting update attempt for %s: bad arguments",
831 			 argp->newpw.pw_name);
832 		return(&result);
833 	}
834 
835 	/*
836 	 * If the caller specified a domain other than our 'default'
837 	 * domain, change the path to master.passwd accordingly.
838 	 */
839 
840 	if (strcmp(argp->domain, yppasswd_domain)) {
841 		snprintf(passfile_buf, sizeof(passfile_buf),
842 			"%s/%s/master.passwd", yp_dir, argp->domain);
843 		passfile = (char *)&passfile_buf;
844 	}
845 
846 	/*
847 	 * Create a filename to hold the original master.passwd
848 	 * so if our call to yppwupdate fails we can roll back
849 	 */
850 	snprintf(passfile_hold_buf, sizeof(passfile_hold_buf),
851 	    "%s.hold", passfile);
852 	passfile_hold = (char *)&passfile_hold_buf;
853 
854 	snprintf(passdir_buf, sizeof(passdir_buf), "%s", passfile);
855 	passdir = dirname(passdir_buf);
856 
857 	if (pw_init(passdir, passfile)) {
858 		yp_error("pw_init() failed");
859 		return &result;
860 	}
861 	if ((pfd = pw_lock()) == -1) {
862 		pw_fini();
863 		yp_error("pw_lock() failed");
864 		return &result;
865 	}
866 	if ((tfd = pw_tmp(-1)) == -1) {
867 		pw_fini();
868 		yp_error("pw_tmp() failed");
869 		return &result;
870 	}
871 	xlate_passwd(&argp->newpw, &newpasswd);
872 	if (pw_copy(pfd, tfd, &newpasswd, NULL) == -1) {
873 		pw_fini();
874 		yp_error("pw_copy() failed");
875 		return &result;
876 	}
877 	if (rename(passfile, passfile_hold) == -1) {
878 		pw_fini();
879 		yp_error("rename of %s to %s failed", passfile,
880 		    passfile_hold);
881 		return &result;
882 	}
883 	if (strcmp(passfile, _PATH_MASTERPASSWD) == 0) {
884 		/*
885 		 * NIS server is exporting the system's master.passwd.
886 		 * Call pw_mkdb to rebuild passwd and the .db files
887 		 */
888 		if (pw_mkdb(argp->newpw.pw_name) == -1) {
889 			pw_fini();
890 			yp_error("pw_mkdb() failed");
891 			rename(passfile_hold, passfile);
892 			return &result;
893 		}
894 	} else {
895 		/*
896 		 * NIS server is exporting a private master.passwd.
897 		 * Rename tempfile into final location
898 		 */
899 		if (rename(pw_tempname(), passfile) == -1) {
900 			pw_fini();
901 			yp_error("rename of %s to %s failed",
902 			    pw_tempname(), passfile);
903 			rename(passfile_hold, passfile);
904 			return &result;
905 		}
906 	}
907 	pw_fini();
908 
909 	if (inplace) {
910 		xlate_passwd(&argp->newpw, &newpasswd);
911 		if ((rval = update_inplace(&newpasswd, argp->domain))) {
912 			yp_error("inplace update failed -- rebuilding maps");
913 		}
914 	}
915 
916 	switch ((pid = fork())) {
917 	case 0:
918 		if (inplace && !rval) {
919     			execlp(MAP_UPDATE_PATH, MAP_UPDATE, passfile,
920 				argp->domain, "pushpw", (char *)NULL);
921     		} else {
922 			execlp(MAP_UPDATE_PATH, MAP_UPDATE, passfile,
923 				argp->domain, (char *)NULL);
924 		}
925     		yp_error("couldn't exec map update process: %s",
926 					strerror(errno));
927 		unlink(passfile);
928 		rename(passfile_hold, passfile);
929     		exit(1);
930 		break;
931 	case -1:
932 		yp_error("fork() failed: %s", strerror(errno));
933 		unlink(passfile);
934 		rename(passfile_hold, passfile);
935 		return(&result);
936 		break;
937 	default:
938 		unlink(passfile_hold);
939 		break;
940 	}
941 
942 	yp_error("performed update of user %s (uid %d) domain %s",
943 						argp->newpw.pw_name,
944 						argp->newpw.pw_uid,
945 						argp->domain);
946 
947 	result = 0;
948 	return(&result);
949 }
950