xref: /freebsd/usr.sbin/rpc.yppasswdd/yppasswdd_server.c (revision d3d381b2b194b4d24853e92eecef55f262688d1a)
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[YPMAXRECORD];
327 	char keybuf[20];
328 	int i;
329 	char *ptr = NULL;
330 	static char yp_last[] = "YP_LAST_MODIFIED";
331 	char yplastbuf[YPMAXRECORD];
332 
333 	snprintf(yplastbuf, sizeof yplastbuf, "%llu",
334 	    (unsigned long long)time(NULL));
335 
336 	for (i = 0; i < 4; i++) {
337 
338 		if (i % 2) {
339 			snprintf(keybuf, sizeof keybuf,
340 			    "%llu", (unsigned long long)pw->pw_uid);
341 			key.data = &keybuf;
342 			key.size = strlen(keybuf);
343 		} else {
344 			key.data = pw->pw_name;
345 			key.size = strlen(pw->pw_name);
346 		}
347 
348 		/*
349 		 * XXX The passwd.byname and passwd.byuid maps come in
350 		 * two flavors: secure and insecure. The secure version
351 		 * has a '*' in the password field whereas the insecure one
352 		 * has a real crypted password. The maps will be insecure
353 		 * if they were built with 'unsecure = TRUE' enabled in
354 		 * /var/yp/Makefile, but we'd have no way of knowing if
355 		 * this has been done unless we were to try parsing the
356 		 * Makefile, which is a disgusting thought. Instead, we
357 		 * read the records from the maps, skip to the first ':'
358 		 * in them, and then look at the character immediately
359 		 * following it. If it's an '*' then the map is 'secure'
360 		 * and we must not insert a real password into the pw_passwd
361 		 * field. If it's not an '*', then we put the real crypted
362 		 * password in.
363 		 */
364 		if (yp_get_record(domain,maps[i],&key,&data,1) != YP_TRUE) {
365 			yp_error("couldn't read %s/%s: %s", domain,
366 						maps[i], strerror(errno));
367 			return(1);
368 		}
369 
370 		if ((ptr = strchr(data.data, ':')) == NULL) {
371 			yp_error("no colon in passwd record?!");
372 			return(1);
373 		}
374 
375 		/*
376 		 * XXX Supposing we have more than one user with the same
377 		 * UID? (Or more than one user with the same name?) We could
378 		 * end up modifying the wrong record if were not careful.
379 		 */
380 		if (i % 2) {
381 			if (strncmp(data.data, pw->pw_name,
382 							strlen(pw->pw_name))) {
383 				yp_error("warning: found entry for UID %d \
384 in map %s@%s with wrong name (%.*s)", pw->pw_uid, maps[i], domain,
385 				    (int)(ptr - (char *)data.data),
386 				    (char *)data.data);
387 				yp_error("there may be more than one user \
388 with the same UID - continuing");
389 				continue;
390 			}
391 		} else {
392 			/*
393 			 * We're really being ultra-paranoid here.
394 			 * This is generally a 'can't happen' condition.
395 			 */
396 			snprintf(pwbuf, sizeof pwbuf, ":%d:%d:", pw->pw_uid,
397 								  pw->pw_gid);
398 			if (!strstr(data.data, pwbuf)) {
399 				yp_error("warning: found entry for user %s \
400 in map %s@%s with wrong UID", pw->pw_name, maps[i], domain);
401 				yp_error("there may be more than one user \
402 with the same name - continuing");
403 				continue;
404 			}
405 		}
406 
407 		if (i < 2) {
408 			snprintf(pwbuf, sizeof pwbuf, formats[i],
409 			   pw->pw_name, pw->pw_passwd, pw->pw_uid,
410 			   pw->pw_gid, pw->pw_class, pw->pw_change,
411 			   pw->pw_expire, pw->pw_gecos, pw->pw_dir,
412 			   pw->pw_shell);
413 		} else {
414 			snprintf(pwbuf, sizeof pwbuf, formats[i],
415 			   pw->pw_name, *(ptr+1) == '*' ? "*" : pw->pw_passwd,
416 			   pw->pw_uid, pw->pw_gid, pw->pw_gecos, pw->pw_dir,
417 			   pw->pw_shell);
418 		}
419 
420 #define FLAGS O_RDWR|O_CREAT
421 
422 		if ((dbp = yp_open_db_rw(domain, maps[i], FLAGS)) == NULL) {
423 			yp_error("couldn't open %s/%s r/w: %s",domain,
424 						maps[i],strerror(errno));
425 			return(1);
426 		}
427 
428 		data.data = pwbuf;
429 		data.size = strlen(pwbuf);
430 
431 		if (yp_put_record(dbp, &key, &data, 1) != YP_TRUE) {
432 			yp_error("failed to update record in %s/%s", domain,
433 								maps[i]);
434 			(void)(dbp->close)(dbp);
435 			return(1);
436 		}
437 
438 		key.data = yp_last;
439 		key.size = strlen(yp_last);
440 		data.data = (char *)&yplastbuf;
441 		data.size = strlen(yplastbuf);
442 
443 		if (yp_put_record(dbp, &key, &data, 1) != YP_TRUE) {
444 			yp_error("failed to update timestamp in %s/%s", domain,
445 								maps[i]);
446 			(void)(dbp->close)(dbp);
447 			return(1);
448 		}
449 
450 		(void)(dbp->close)(dbp);
451 	}
452 
453 	return(0);
454 }
455 
456 int *
457 yppasswdproc_update_1_svc(yppasswd *argp, struct svc_req *rqstp)
458 {
459 	static int  result;
460 	struct sockaddr_in *rqhost;
461 	DBT key, data;
462 	int rval = 0;
463 	int pfd, tfd;
464 	int pid;
465 	int passwd_changed = 0;
466 	int shell_changed = 0;
467 	int gecos_changed = 0;
468 	char *cryptpw;
469 	char *oldshell = NULL;
470 	char *oldgecos = NULL;
471 	char *passfile_hold;
472 	char passfile_buf[MAXPATHLEN + 2];
473 	char passfile_hold_buf[MAXPATHLEN + 2];
474 	char *domain = yppasswd_domain;
475 	static struct sockaddr_in clntaddr;
476 	static struct timeval t_saved, t_test;
477 
478 	/*
479 	 * Normal user updates always use the 'default' master.passwd file.
480 	 */
481 
482 	passfile = passfile_default;
483 	result = 1;
484 
485 	rqhost = svc_getcaller(rqstp->rq_xprt);
486 
487 	gettimeofday(&t_test, NULL);
488 	if (!bcmp(rqhost, &clntaddr, sizeof *rqhost) &&
489 		t_test.tv_sec > t_saved.tv_sec &&
490 		t_test.tv_sec - t_saved.tv_sec < 300) {
491 
492 		bzero(&clntaddr, sizeof clntaddr);
493 		bzero(&t_saved, sizeof t_saved);
494 		return(NULL);
495 	}
496 
497 	bcopy(rqhost, &clntaddr, sizeof clntaddr);
498 	gettimeofday(&t_saved, NULL);
499 
500 	if (yp_access(resvport ? "master.passwd.byname" : NULL, rqstp)) {
501 		yp_error("rejected update request from unauthorized host");
502 		svcerr_auth(rqstp->rq_xprt, AUTH_BADCRED);
503 		return(&result);
504 	}
505 
506 	/*
507 	 * Step one: find the user. (It's kinda pointless to
508 	 * proceed if the user doesn't exist.) We look for the
509 	 * user in the master.passwd.byname database, _NOT_ by
510 	 * using getpwent() and friends! We can't use getpwent()
511 	 * since the NIS master server is not guaranteed to be
512 	 * configured as an NIS client.
513 	 */
514 
515 	if (multidomain) {
516 		if ((domain = find_domain(&argp->newpw)) == NULL) {
517 			yp_error("multidomain lookup failed - aborting update");
518 			return(&result);
519 		} else
520 			yp_error("updating user %s in domain %s",
521 					argp->newpw.pw_name, domain);
522 	}
523 
524 	key.data = argp->newpw.pw_name;
525 	key.size = strlen(argp->newpw.pw_name);
526 
527 	if ((rval = yp_get_record(domain,"master.passwd.byname",
528 		  	&key, &data, 0)) != YP_TRUE) {
529 		if (rval == YP_NOKEY) {
530 			yp_error("user %s not found in passwd database",
531 			 	argp->newpw.pw_name);
532 		} else {
533 			yp_error("database access error: %s",
534 			 	yperr_string(rval));
535 		}
536 		return(&result);
537 	}
538 
539 	/* Nul terminate, please. */
540 	*((char *)data.data + data.size) = '\0';
541 
542 	copy_yp_pass(data.data, 1, data.size);
543 
544 	/* Step 2: check that the supplied oldpass is valid. */
545 
546 	cryptpw = crypt(argp->oldpass, yp_password.pw_passwd);
547 	if (cryptpw == NULL || strcmp(cryptpw, yp_password.pw_passwd)) {
548 		yp_error("rejected change attempt -- bad password");
549 		yp_error("client address: %s username: %s",
550 			  inet_ntoa(rqhost->sin_addr),
551 			  argp->newpw.pw_name);
552 		return(&result);
553 	}
554 
555 	/* Step 3: validate the arguments passed to us by the client. */
556 
557 	if (validate(&yp_password, &argp->newpw)) {
558 		yp_error("rejecting change attempt: bad arguments");
559 		yp_error("client address: %s username: %s",
560 			 inet_ntoa(rqhost->sin_addr),
561 			 argp->newpw.pw_name);
562 		svcerr_decode(rqstp->rq_xprt);
563 		return(&result);
564 	}
565 
566 	/* Step 4: update the user's passwd structure. */
567 
568 	if (!no_chsh && strcmp(argp->newpw.pw_shell, yp_password.pw_shell)) {
569 		oldshell = yp_password.pw_shell;
570 		yp_password.pw_shell = argp->newpw.pw_shell;
571 		shell_changed++;
572 	}
573 
574 
575 	if (!no_chfn && strcmp(argp->newpw.pw_gecos, yp_password.pw_gecos)) {
576 		oldgecos = yp_password.pw_gecos;
577 		yp_password.pw_gecos = argp->newpw.pw_gecos;
578 		gecos_changed++;
579 	}
580 
581 	if (strcmp(argp->newpw.pw_passwd, yp_password.pw_passwd)) {
582 		yp_password.pw_passwd = argp->newpw.pw_passwd;
583 		yp_password.pw_change = 0;
584 		passwd_changed++;
585 	}
586 
587 	/*
588 	 * If the caller specified a domain other than our 'default'
589 	 * domain, change the path to master.passwd accordingly.
590 	 */
591 
592 	if (strcmp(domain, yppasswd_domain)) {
593 		snprintf(passfile_buf, sizeof(passfile_buf),
594 			"%s/%s/master.passwd", yp_dir, domain);
595 		passfile = (char *)&passfile_buf;
596 	}
597 
598 	/*
599 	 * Create a filename to hold the original master.passwd
600 	 * so if our call to yppwupdate fails we can roll back
601 	 */
602 	snprintf(passfile_hold_buf, sizeof(passfile_hold_buf),
603 	    "%s.hold", passfile);
604 	passfile_hold = (char *)&passfile_hold_buf;
605 
606 
607 	/* Step 5: make a new password file with the updated info. */
608 
609 	if (pw_init(dirname(passfile), passfile)) {
610 		yp_error("pw_init() failed");
611 		return &result;
612 	}
613 	if ((pfd = pw_lock()) == -1) {
614 		pw_fini();
615 		yp_error("pw_lock() failed");
616 		return &result;
617 	}
618 	if ((tfd = pw_tmp(-1)) == -1) {
619 		pw_fini();
620 		yp_error("pw_tmp() failed");
621 		return &result;
622 	}
623 	if (pw_copy(pfd, tfd, &yp_password, NULL) == -1) {
624 		pw_fini();
625 		yp_error("pw_copy() failed");
626 		return &result;
627 	}
628 	if (rename(passfile, passfile_hold) == -1) {
629 		pw_fini();
630 		yp_error("rename of %s to %s failed", passfile,
631 		    passfile_hold);
632 		return &result;
633 	}
634 
635 	if (strcmp(passfile, _PATH_MASTERPASSWD) == 0) {
636 		/*
637 		 * NIS server is exporting the system's master.passwd.
638 		 * Call pw_mkdb to rebuild passwd and the .db files
639 		 */
640 		if (pw_mkdb(yp_password.pw_name) == -1) {
641 			pw_fini();
642 			yp_error("pw_mkdb() failed");
643 			rename(passfile_hold, passfile);
644 			return &result;
645 		}
646 	} else {
647 		/*
648 		 * NIS server is exporting a private master.passwd.
649 		 * Rename tempfile into final location
650 		 */
651 		if (rename(pw_tempname(), passfile) == -1) {
652 			pw_fini();
653 			yp_error("rename of %s to %s failed",
654 			    pw_tempname(), passfile);
655 			rename(passfile_hold, passfile);
656 			return &result;
657 		}
658 	}
659 
660 	pw_fini();
661 
662 	if (inplace) {
663 		if ((rval = update_inplace(&yp_password, domain))) {
664 			yp_error("inplace update failed -- rebuilding maps");
665 		}
666 	}
667 
668 	switch ((pid = fork())) {
669 	case 0:
670 		if (inplace && !rval) {
671     			execlp(MAP_UPDATE_PATH, MAP_UPDATE, passfile,
672 				yppasswd_domain, "pushpw", (char *)NULL);
673 		} else {
674     			execlp(MAP_UPDATE_PATH, MAP_UPDATE, passfile,
675 				yppasswd_domain, (char *)NULL);
676 		}
677     		yp_error("couldn't exec map update process: %s",
678 					strerror(errno));
679 		unlink(passfile);
680 		rename(passfile_hold, passfile);
681     		exit(1);
682 		break;
683 	case -1:
684 		yp_error("fork() failed: %s", strerror(errno));
685 		unlink(passfile);
686 		rename(passfile_hold, passfile);
687 		return(&result);
688 		break;
689 	default:
690 		unlink(passfile_hold);
691 		break;
692 	}
693 
694 	if (verbose) {
695 		yp_error("update completed for user %s (uid %d) in %s:",
696 		    argp->newpw.pw_name, argp->newpw.pw_uid, passfile);
697 
698 		if (passwd_changed)
699 			yp_error("password changed");
700 
701 		if (gecos_changed)
702 			yp_error("gecos changed ('%s' -> '%s')",
703 					oldgecos, argp->newpw.pw_gecos);
704 
705 		if (shell_changed)
706 			yp_error("shell changed ('%s' -> '%s')",
707 					oldshell, argp->newpw.pw_shell);
708 	}
709 
710 	result = 0;
711 	return (&result);
712 }
713 
714 /*
715  * Note that this function performs a little less sanity checking
716  * than the last one. Since only the superuser is allowed to use it,
717  * it is assumed that the caller knows what he's doing.
718  */
719 int *
720 yppasswdproc_update_master_1_svc(master_yppasswd *argp,
721     struct svc_req *rqstp)
722 {
723 	static int result;
724 	int pfd, tfd;
725 	int pid;
726 	uid_t uid;
727 	int rval = 0;
728 	DBT key, data;
729 	char *passfile_hold;
730 	char passfile_buf[MAXPATHLEN + 2];
731 	char passfile_hold_buf[MAXPATHLEN + 2];
732 	struct sockaddr_in *rqhost;
733 	SVCXPRT	*transp;
734 	struct passwd newpasswd;
735 
736 	result = 1;
737 	transp = rqstp->rq_xprt;
738 
739 	/*
740 	 * NO AF_INET CONNETCIONS ALLOWED!
741 	 */
742 	rqhost = svc_getcaller(transp);
743 	if (rqhost->sin_family != AF_UNIX) {
744 		yp_error("Alert! %s/%d attempted to use superuser-only \
745 procedure!\n", inet_ntoa(rqhost->sin_addr), rqhost->sin_port);
746 		svcerr_auth(transp, AUTH_BADCRED);
747 		return(&result);
748 	}
749 
750 	if (rqstp->rq_cred.oa_flavor != AUTH_SYS) {
751 		yp_error("caller didn't send proper credentials");
752 		svcerr_auth(transp, AUTH_BADCRED);
753 		return(&result);
754 	}
755 
756 	if (__rpc_get_local_uid(transp, &uid) < 0) {
757 		yp_error("caller didn't send proper credentials");
758 		svcerr_auth(transp, AUTH_BADCRED);
759 		return(&result);
760 	}
761 
762 	if (uid) {
763 		yp_error("caller euid is %d, expecting 0 -- rejecting request",
764 		    uid);
765 		svcerr_auth(rqstp->rq_xprt, AUTH_BADCRED);
766 		return(&result);
767 	}
768 
769 	passfile = passfile_default;
770 
771 	key.data = argp->newpw.pw_name;
772 	key.size = strlen(argp->newpw.pw_name);
773 
774 	/*
775 	 * The superuser may add entries to the passwd maps if
776 	 * rpc.yppasswdd is started with the -a flag. Paranoia
777 	 * prevents me from allowing additions by default.
778 	 */
779 	if ((rval = yp_get_record(argp->domain, "master.passwd.byname",
780 			  &key, &data, 0)) != YP_TRUE) {
781 		if (rval == YP_NOKEY) {
782 			yp_error("user %s not found in passwd database",
783 				 argp->newpw.pw_name);
784 			if (allow_additions)
785 				yp_error("notice: adding user %s to \
786 master.passwd database for domain %s", argp->newpw.pw_name, argp->domain);
787 			else
788 				yp_error("restart rpc.yppasswdd with the -a flag to \
789 allow additions to be made to the password database");
790 		} else {
791 			yp_error("database access error: %s",
792 				 yperr_string(rval));
793 		}
794 		if (!allow_additions)
795 			return(&result);
796 	} else {
797 
798 		/* Nul terminate, please. */
799 		*((char *)data.data + data.size) = '\0';
800 
801 		copy_yp_pass(data.data, 1, data.size);
802 	}
803 
804 	/*
805 	 * Perform a small bit of sanity checking.
806 	 */
807 	if (validate_master(rval == YP_TRUE ? &yp_password:NULL,&argp->newpw)){
808 		yp_error("rejecting update attempt for %s: bad arguments",
809 			 argp->newpw.pw_name);
810 		return(&result);
811 	}
812 
813 	/*
814 	 * If the caller specified a domain other than our 'default'
815 	 * domain, change the path to master.passwd accordingly.
816 	 */
817 
818 	if (strcmp(argp->domain, yppasswd_domain)) {
819 		snprintf(passfile_buf, sizeof(passfile_buf),
820 			"%s/%s/master.passwd", yp_dir, argp->domain);
821 		passfile = (char *)&passfile_buf;
822 	}
823 
824 	/*
825 	 * Create a filename to hold the original master.passwd
826 	 * so if our call to yppwupdate fails we can roll back
827 	 */
828 	snprintf(passfile_hold_buf, sizeof(passfile_hold_buf),
829 	    "%s.hold", passfile);
830 	passfile_hold = (char *)&passfile_hold_buf;
831 
832 	if (pw_init(dirname(passfile), passfile)) {
833 		yp_error("pw_init() failed");
834 		return &result;
835 	}
836 	if ((pfd = pw_lock()) == -1) {
837 		pw_fini();
838 		yp_error("pw_lock() failed");
839 		return &result;
840 	}
841 	if ((tfd = pw_tmp(-1)) == -1) {
842 		pw_fini();
843 		yp_error("pw_tmp() failed");
844 		return &result;
845 	}
846 	xlate_passwd(&argp->newpw, &newpasswd);
847 	if (pw_copy(pfd, tfd, &newpasswd, NULL) == -1) {
848 		pw_fini();
849 		yp_error("pw_copy() failed");
850 		return &result;
851 	}
852 	if (rename(passfile, passfile_hold) == -1) {
853 		pw_fini();
854 		yp_error("rename of %s to %s failed", passfile,
855 		    passfile_hold);
856 		return &result;
857 	}
858 	if (strcmp(passfile, _PATH_MASTERPASSWD) == 0) {
859 		/*
860 		 * NIS server is exporting the system's master.passwd.
861 		 * Call pw_mkdb to rebuild passwd and the .db files
862 		 */
863 		if (pw_mkdb(argp->newpw.pw_name) == -1) {
864 			pw_fini();
865 			yp_error("pw_mkdb() failed");
866 			rename(passfile_hold, passfile);
867 			return &result;
868 		}
869 	} else {
870 		/*
871 		 * NIS server is exporting a private master.passwd.
872 		 * Rename tempfile into final location
873 		 */
874 		if (rename(pw_tempname(), passfile) == -1) {
875 			pw_fini();
876 			yp_error("rename of %s to %s failed",
877 			    pw_tempname(), passfile);
878 			rename(passfile_hold, passfile);
879 			return &result;
880 		}
881 	}
882 	pw_fini();
883 
884 	if (inplace) {
885 		xlate_passwd(&argp->newpw, &newpasswd);
886 		if ((rval = update_inplace(&newpasswd, argp->domain))) {
887 			yp_error("inplace update failed -- rebuilding maps");
888 		}
889 	}
890 
891 	switch ((pid = fork())) {
892 	case 0:
893 		if (inplace && !rval) {
894     			execlp(MAP_UPDATE_PATH, MAP_UPDATE, passfile,
895 				argp->domain, "pushpw", (char *)NULL);
896     		} else {
897 			execlp(MAP_UPDATE_PATH, MAP_UPDATE, passfile,
898 				argp->domain, (char *)NULL);
899 		}
900     		yp_error("couldn't exec map update process: %s",
901 					strerror(errno));
902 		unlink(passfile);
903 		rename(passfile_hold, passfile);
904     		exit(1);
905 		break;
906 	case -1:
907 		yp_error("fork() failed: %s", strerror(errno));
908 		unlink(passfile);
909 		rename(passfile_hold, passfile);
910 		return(&result);
911 		break;
912 	default:
913 		unlink(passfile_hold);
914 		break;
915 	}
916 
917 	yp_error("performed update of user %s (uid %d) domain %s",
918 						argp->newpw.pw_name,
919 						argp->newpw.pw_uid,
920 						argp->domain);
921 
922 	result = 0;
923 	return(&result);
924 }
925