xref: /illumos-gate/usr/src/lib/libc/port/gen/getpwnam_r.c (revision cd277642e0bdc71a7f57c550df1279b0c091d6e2)
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 2009 Sun Microsystems, Inc.  All rights reserved.
24  * Use is subject to license terms.
25  * Copyright (c) 2016 by Delphix. All rights reserved.
26  */
27 
28 #include "lint.h"
29 #include <sys/types.h>
30 #include <pwd.h>
31 #include <nss_dbdefs.h>
32 #include <stdio.h>
33 #include <synch.h>
34 #include <sys/param.h>
35 #include <string.h>
36 #include <stdlib.h>
37 #include <sys/mman.h>
38 #include <errno.h>
39 
40 int str2passwd(const char *, int, void *,
41 	char *, int);
42 
43 static DEFINE_NSS_DB_ROOT(db_root);
44 static DEFINE_NSS_GETENT(context);
45 
46 void
47 _nss_initf_passwd(nss_db_params_t *p)
48 {
49 	p->name	= NSS_DBNAM_PASSWD;
50 	p->default_config = NSS_DEFCONF_PASSWD;
51 }
52 
53 #include <getxby_door.h>
54 
55 struct passwd *
56 _uncached_getpwuid_r(uid_t uid, struct passwd *result, char *buffer,
57 	int buflen);
58 
59 struct passwd *
60 _uncached_getpwnam_r(const char *name, struct passwd *result, char *buffer,
61     int buflen);
62 
63 /*
64  * POSIX.1c Draft-6 version of the function getpwnam_r.
65  * It was implemented by Solaris 2.3.
66  */
67 struct passwd *
68 getpwnam_r(const char *name, struct passwd *result, char *buffer, int buflen)
69 {
70 	nss_XbyY_args_t arg;
71 
72 	if (name == (const char *)NULL) {
73 		errno = ERANGE;
74 		return (NULL);
75 	}
76 	NSS_XbyY_INIT(&arg, result, buffer, buflen, str2passwd);
77 	arg.key.name = name;
78 	(void) nss_search(&db_root, _nss_initf_passwd, NSS_DBOP_PASSWD_BYNAME,
79 	    &arg);
80 	return ((struct passwd *)NSS_XbyY_FINI(&arg));
81 }
82 
83 /*
84  * POSIX.1c Draft-6 version of the function getpwuid_r.
85  * It was implemented by Solaris 2.3.
86  */
87 struct passwd *
88 getpwuid_r(uid_t uid, struct passwd *result, char *buffer, int buflen)
89 {
90 	nss_XbyY_args_t arg;
91 
92 	NSS_XbyY_INIT(&arg, result, buffer, buflen, str2passwd);
93 	arg.key.uid = uid;
94 	(void) nss_search(&db_root, _nss_initf_passwd, NSS_DBOP_PASSWD_BYUID,
95 	    &arg);
96 	return ((struct passwd *)NSS_XbyY_FINI(&arg));
97 }
98 
99 
100 struct passwd *
101 _uncached_getpwuid_r(uid_t uid, struct passwd *result, char *buffer,
102 	int buflen)
103 {
104 	nss_XbyY_args_t arg;
105 
106 	NSS_XbyY_INIT(&arg, result, buffer, buflen, str2passwd);
107 	arg.key.uid = uid;
108 	(void) nss_search(&db_root, _nss_initf_passwd, NSS_DBOP_PASSWD_BYUID,
109 	    &arg);
110 	return ((struct passwd *)NSS_XbyY_FINI(&arg));
111 }
112 
113 
114 /*
115  * POSIX.1c standard version of the function getpwuid_r.
116  * User gets it via static getpwuid_r from the header file.
117  */
118 int
119 __posix_getpwuid_r(uid_t uid, struct passwd *pwd, char *buffer,
120     size_t bufsize, struct passwd **result)
121 {
122 	int nerrno = 0;
123 	int oerrno = errno;
124 
125 	errno = 0;
126 	if ((*result = getpwuid_r(uid, pwd, buffer, (uintptr_t)bufsize))
127 	    == NULL) {
128 			nerrno = errno;
129 	}
130 	errno = oerrno;
131 	return (nerrno);
132 }
133 
134 struct passwd *
135 _uncached_getpwnam_r(const char *name, struct passwd *result, char *buffer,
136 	int buflen)
137 {
138 	nss_XbyY_args_t arg;
139 
140 	NSS_XbyY_INIT(&arg, result, buffer, buflen, str2passwd);
141 	arg.key.name = name;
142 	(void) nss_search(&db_root, _nss_initf_passwd, NSS_DBOP_PASSWD_BYNAME,
143 	    &arg);
144 	return ((struct passwd *)NSS_XbyY_FINI(&arg));
145 }
146 
147 /*
148  * POSIX.1c standard version of the function getpwnam_r.
149  * User gets it via static getpwnam_r from the header file.
150  */
151 int
152 __posix_getpwnam_r(const char *name, struct passwd *pwd, char *buffer,
153     size_t bufsize, struct passwd **result)
154 {
155 	int nerrno = 0;
156 	int oerrno = errno;
157 
158 	errno = 0;
159 	if ((*result = getpwnam_r(name, pwd, buffer, (uintptr_t)bufsize))
160 	    == NULL) {
161 			nerrno = errno;
162 	}
163 	errno = oerrno;
164 	return (nerrno);
165 }
166 
167 void
168 setpwent(void)
169 {
170 	nss_setent(&db_root, _nss_initf_passwd, &context);
171 }
172 
173 void
174 endpwent(void)
175 {
176 	nss_endent(&db_root, _nss_initf_passwd, &context);
177 	nss_delete(&db_root);
178 }
179 
180 struct passwd *
181 getpwent_r(struct passwd *result, char *buffer, int buflen)
182 {
183 	nss_XbyY_args_t arg;
184 	char		*nam;
185 
186 	/* In getXXent_r(), protect the unsuspecting caller from +/- entries */
187 
188 	do {
189 		NSS_XbyY_INIT(&arg, result, buffer, buflen, str2passwd);
190 		/* No key to fill in */
191 		(void) nss_getent(&db_root, _nss_initf_passwd, &context, &arg);
192 	} while (arg.returnval != 0 &&
193 	    (nam = ((struct passwd *)arg.returnval)->pw_name) != 0 &&
194 	    (*nam == '+' || *nam == '-'));
195 
196 	return ((struct passwd *)NSS_XbyY_FINI(&arg));
197 }
198 
199 struct passwd *
200 fgetpwent_r(FILE *f, struct passwd *result, char *buffer, int buflen)
201 {
202 	extern void	_nss_XbyY_fgets(FILE *, nss_XbyY_args_t *);
203 	nss_XbyY_args_t	arg;
204 
205 	/* ... but in fgetXXent_r, the caller deserves any +/- entry it gets */
206 
207 	/* No key to fill in */
208 	NSS_XbyY_INIT(&arg, result, buffer, buflen, str2passwd);
209 	_nss_XbyY_fgets(f, &arg);
210 	return ((struct passwd *)NSS_XbyY_FINI(&arg));
211 }
212 
213 static char *
214 gettok(char **nextpp)
215 {
216 	char	*p = *nextpp;
217 	char	*q = p;
218 	char	c;
219 
220 	if (p == 0)
221 		return (0);
222 
223 	while ((c = *q) != '\0' && c != ':')
224 		q++;
225 
226 	if (c == '\0')
227 		*nextpp = 0;
228 	else {
229 		*q++ = '\0';
230 		*nextpp = q;
231 	}
232 	return (p);
233 }
234 
235 /*
236  * Return values: 0 = success, 1 = parse error, 2 = erange ...
237  * The structure pointer passed in is a structure in the caller's space
238  * wherein the field pointers would be set to areas in the buffer if
239  * need be. instring and buffer should be separate areas.
240  */
241 int
242 str2passwd(const char *instr, int lenstr, void *ent, char *buffer, int buflen)
243 {
244 	struct passwd	*passwd	= (struct passwd *)ent;
245 	char		*p, *next;
246 	int		black_magic;	/* "+" or "-" entry */
247 	ulong_t		tmp;
248 
249 	if (lenstr + 1 > buflen)
250 		return (NSS_STR_PARSE_ERANGE);
251 
252 	/*
253 	 * We copy the input string into the output buffer and
254 	 * operate on it in place.
255 	 */
256 	if (instr != buffer) {
257 		/* Overlapping buffer copies are OK */
258 		(void) memmove(buffer, instr, lenstr);
259 		buffer[lenstr] = '\0';
260 	}
261 
262 	/* quick exit do not entry fill if not needed */
263 	if (ent == (void *)NULL)
264 		return (NSS_STR_PARSE_SUCCESS);
265 
266 	next = buffer;
267 
268 	passwd->pw_name = p = gettok(&next);		/* username */
269 	if (*p == '\0') {
270 		/* Empty username;  not allowed */
271 		return (NSS_STR_PARSE_PARSE);
272 	}
273 	black_magic = (*p == '+' || *p == '-');
274 	if (black_magic) {
275 		passwd->pw_uid = UID_NOBODY;
276 		passwd->pw_gid = GID_NOBODY;
277 		/*
278 		 *  pwconv tests pw_passwd and pw_age == NULL
279 		 */
280 		passwd->pw_passwd  = "";
281 		passwd->pw_age	= "";
282 		/*
283 		 * the rest of the passwd entry is "optional"
284 		 */
285 		passwd->pw_comment = "";
286 		passwd->pw_gecos = "";
287 		passwd->pw_dir	= "";
288 		passwd->pw_shell = "";
289 	}
290 
291 	passwd->pw_passwd = p = gettok(&next);		/* password */
292 	if (p == 0) {
293 		if (black_magic)
294 			return (NSS_STR_PARSE_SUCCESS);
295 		else
296 			return (NSS_STR_PARSE_PARSE);
297 	}
298 	for (; *p != '\0';  p++) {			/* age */
299 		if (*p == ',') {
300 			*p++ = '\0';
301 			break;
302 		}
303 	}
304 	passwd->pw_age = p;
305 
306 	p = next;					/* uid */
307 	if (p == 0 || *p == '\0') {
308 		if (black_magic)
309 			return (NSS_STR_PARSE_SUCCESS);
310 		else
311 			return (NSS_STR_PARSE_PARSE);
312 	}
313 	if (!black_magic) {
314 		/*
315 		 * strtoul returns unsigned long which is
316 		 * 8 bytes on a 64-bit system. We don't want
317 		 * to assign it directly to passwd->pw_uid
318 		 * which is 4 bytes or else we will end up
319 		 * truncating the value.
320 		 */
321 		errno = 0;
322 		tmp = strtoul(p, &next, 10);
323 		if (next == p || errno != 0) {
324 			/* uid field should be nonempty */
325 			/* also check errno from strtoul */
326 			return (NSS_STR_PARSE_PARSE);
327 		}
328 		/*
329 		 * The old code (in 2.0 through 2.5) would check
330 		 * for the uid being negative, or being greater
331 		 * than 60001 (the rfs limit).  If it met either of
332 		 * these conditions, the uid was translated to 60001.
333 		 *
334 		 * Now we just check for -1 (UINT32_MAX); anything else
335 		 * is administrative policy
336 		 */
337 		if (tmp >= UINT32_MAX)
338 			passwd->pw_uid = UID_NOBODY;
339 		else
340 			passwd->pw_uid = (uid_t)tmp;
341 	}
342 	if (*next++ != ':') {
343 		if (black_magic)
344 			(void) gettok(&next);
345 		else
346 			return (NSS_STR_PARSE_PARSE);
347 	}
348 	p = next;					/* gid */
349 	if (p == 0 || *p == '\0') {
350 		if (black_magic)
351 			return (NSS_STR_PARSE_SUCCESS);
352 		else
353 			return (NSS_STR_PARSE_PARSE);
354 	}
355 	if (!black_magic) {
356 		errno = 0;
357 		tmp = strtoul(p, &next, 10);
358 		if (next == p || errno != 0) {
359 			/* gid field should be nonempty */
360 			/* also check errno from strtoul */
361 			return (NSS_STR_PARSE_PARSE);
362 		}
363 		/*
364 		 * gid should not be -1; anything else
365 		 * is administrative policy.
366 		 */
367 		if (tmp >= UINT32_MAX)
368 			passwd->pw_gid = GID_NOBODY;
369 		else
370 			passwd->pw_gid = (gid_t)tmp;
371 	}
372 	if (*next++ != ':') {
373 		if (black_magic)
374 			(void) gettok(&next);
375 		else
376 			return (NSS_STR_PARSE_PARSE);
377 	}
378 
379 	passwd->pw_gecos = passwd->pw_comment = p = gettok(&next);
380 	if (p == 0) {
381 		if (black_magic)
382 			return (NSS_STR_PARSE_SUCCESS);
383 		else
384 			return (NSS_STR_PARSE_PARSE);
385 	}
386 
387 	passwd->pw_dir = p = gettok(&next);
388 	if (p == 0) {
389 		if (black_magic)
390 			return (NSS_STR_PARSE_SUCCESS);
391 		else
392 			return (NSS_STR_PARSE_PARSE);
393 	}
394 
395 	passwd->pw_shell = p = gettok(&next);
396 	if (p == 0) {
397 		if (black_magic)
398 			return (NSS_STR_PARSE_SUCCESS);
399 		else
400 			return (NSS_STR_PARSE_PARSE);
401 	}
402 
403 	/* Better not be any more fields... */
404 	if (next == 0) {
405 		/* Successfully parsed and stored */
406 		return (NSS_STR_PARSE_SUCCESS);
407 	}
408 	return (NSS_STR_PARSE_PARSE);
409 }
410