xref: /illumos-gate/usr/src/lib/nsswitch/ad/common/getpwnam.c (revision 8119dad84d6416f13557b0ba8e2aaf9064cbcfd3)
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  * Copyright (c) 2008, 2010, Oracle and/or its affiliates. All rights reserved.
23  */
24 
25 #include <pwd.h>
26 #include <idmap.h>
27 #include <ctype.h>
28 #include "ad_common.h"
29 
30 /* passwd attributes and filters */
31 #define	_PWD_DN			"dn"
32 #define	_PWD_SAN		"sAMAccountName"
33 #define	_PWD_OBJSID		"objectSid"
34 #define	_PWD_PRIMARYGROUPID	"primaryGroupID"
35 #define	_PWD_CN			"cn"
36 #define	_PWD_HOMEDIRECTORY	"homedirectory"
37 #define	_PWD_LOGINSHELL		"loginshell"
38 #define	_PWD_OBJCLASS		"objectClass"
39 
40 #define	_F_GETPWNAM		"(sAMAccountName=%.*s)"
41 #define	_F_GETPWUID		"(objectSid=%s)"
42 
43 static const char *pwd_attrs[] = {
44 	_PWD_SAN,
45 	_PWD_OBJSID,
46 	_PWD_PRIMARYGROUPID,
47 	_PWD_CN,
48 	_PWD_HOMEDIRECTORY,
49 	_PWD_LOGINSHELL,
50 	_PWD_OBJCLASS,
51 	(char *)NULL
52 };
53 
54 static int
55 update_buffer(ad_backend_ptr be, nss_XbyY_args_t *argp,
56 		const char *name, const char *domain,
57 		uid_t uid, gid_t gid, const char *gecos,
58 		const char *homedir, const char *shell)
59 {
60 	int	buflen;
61 	char	*buffer;
62 
63 	if (be->db_type == NSS_AD_DB_PASSWD_BYNAME) {
64 		/*
65 		 * The canonical name obtained from AD lookup may not match
66 		 * the case of the name (i.e. key) in the request. Therefore,
67 		 * use the name from the request to construct the result.
68 		 */
69 		buflen = snprintf(NULL, 0, "%s:%s:%u:%u:%s:%s:%s",
70 		    argp->key.name, "x", uid, gid, gecos, homedir, shell) + 1;
71 	} else {
72 		if (domain == NULL)
73 			domain = WK_DOMAIN;
74 		buflen = snprintf(NULL, 0, "%s@%s:%s:%u:%u:%s:%s:%s",
75 		    name, domain, "x", uid, gid, gecos, homedir, shell) + 1;
76 	}
77 
78 
79 	if (argp->buf.result != NULL) {
80 		buffer = be->buffer = malloc(buflen);
81 		if (be->buffer == NULL)
82 			return (-1);
83 		be->buflen = buflen;
84 	} else {
85 		if (buflen > argp->buf.buflen)
86 			return (-1);
87 		buflen = argp->buf.buflen;
88 		buffer = argp->buf.buffer;
89 	}
90 
91 	if (be->db_type == NSS_AD_DB_PASSWD_BYNAME)
92 		(void) snprintf(buffer, buflen, "%s:%s:%u:%u:%s:%s:%s",
93 		    argp->key.name, "x", uid, gid, gecos, homedir, shell);
94 	else
95 		(void) snprintf(buffer, buflen, "%s@%s:%s:%u:%u:%s:%s:%s",
96 		    name, domain, "x", uid, gid, gecos, homedir, shell);
97 	return (0);
98 }
99 
100 
101 #define	NET_SCHEME	"/net"
102 
103 /*
104  * 1) If the homeDirectory string is in UNC format then convert it into
105  * a /net format. This needs to be revisited later but is fine for now
106  * because Solaris does not support -hosts automount map for CIFS yet.
107  *
108  * 2) If homeDirectory contains ':' then return NULL because ':' is the
109  * delimiter in passwd entries and may break apps that parse these entries.
110  *
111  * 3) For all other cases return the same string that was passed to
112  * this function.
113  */
114 static
115 char *
116 process_homedir(char *homedir)
117 {
118 	size_t	len, smb_len;
119 	char	*smb_homedir;
120 	int	i, slash = 0;
121 
122 	len = strlen(homedir);
123 
124 	if (strchr(homedir, ':') != NULL)
125 		/*
126 		 * Ignore paths that have colon ':' because ':' is a
127 		 * delimiter for the passwd entry.
128 		 */
129 		return (NULL);
130 
131 	if (!(len > 1 && homedir[0] == '\\' && homedir[1] == '\\'))
132 		/* Keep homedir intact if not in UNC format */
133 		return (homedir);
134 
135 	/*
136 	 * Convert UNC string into /net format
137 	 * Example: \\server\abc -> /net/server/abc
138 	 */
139 	smb_len = len + 1 + sizeof (NET_SCHEME);
140 	if ((smb_homedir = calloc(1, smb_len)) == NULL)
141 		return (NULL);
142 	(void) strlcpy(smb_homedir, NET_SCHEME, smb_len);
143 	for (i = strlen(smb_homedir); *homedir != '\0'; homedir++) {
144 		if (*homedir == '\\') {
145 			/* Reduce double backslashes into one */
146 			if (slash)
147 				slash = 0;
148 			else {
149 				slash = 1;
150 				smb_homedir[i++] = '/';
151 			}
152 		} else {
153 			smb_homedir[i++] = *homedir;
154 			slash = 0;
155 		}
156 	}
157 	return (smb_homedir);
158 }
159 
160 /*
161  * _nss_ad_passwd2str is the data marshaling method for the passwd getXbyY
162  * (e.g., getbyuid(), getbyname(), getpwent()) backend processes. This method is
163  * called after a successful AD search has been performed. This method will
164  * parse the AD search values into the file format.
165  * e.g.
166  *
167  * blue@whale:x:123456:10:Blue Whale:/:
168  *
169  */
170 static int
171 _nss_ad_passwd2str(ad_backend_ptr be, nss_XbyY_args_t *argp)
172 {
173 	int			nss_result;
174 	adutils_result_t	*result = be->result;
175 	const adutils_entry_t	*entry;
176 	char			**sid_v, *ptr, **pgid_v, *end;
177 	ulong_t			tmp;
178 	uint32_t		urid, grid;
179 	uid_t			uid;
180 	gid_t			gid;
181 	idmap_stat		gstat;
182 	idmap_get_handle_t 	*ig = NULL;
183 	char			**name_v, **dn_v, *domain = NULL;
184 	char			**gecos_v, **shell_v;
185 	char			**homedir_v = NULL, *homedir = NULL;
186 	char			*NULL_STR = "";
187 
188 	if (result == NULL)
189 		return (NSS_STR_PARSE_PARSE);
190 	entry = adutils_getfirstentry(result);
191 	nss_result = NSS_STR_PARSE_PARSE;
192 
193 	/* Create handles for idmap service */
194 	if (idmap_get_create(&ig) != 0)
195 		goto result_pwd2str;
196 
197 	/* Get name */
198 	name_v = adutils_getattr(entry, _PWD_SAN);
199 	if (name_v == NULL || name_v[0] == NULL || *name_v[0] == '\0')
200 		goto result_pwd2str;
201 
202 	/* Get domain */
203 	dn_v = adutils_getattr(entry, _PWD_DN);
204 	if (dn_v == NULL || dn_v[0] == NULL || *dn_v[0] == '\0')
205 		goto result_pwd2str;
206 	domain = adutils_dn2dns(dn_v[0]);
207 
208 	/* Get objectSID (in text format) */
209 	sid_v = adutils_getattr(entry, _PWD_OBJSID);
210 	if (sid_v == NULL || sid_v[0] == NULL || *sid_v[0] == '\0')
211 		goto result_pwd2str;
212 
213 	/* Break SID into prefix and rid */
214 	if ((ptr = strrchr(sid_v[0], '-')) == NULL)
215 		goto result_pwd2str;
216 	*ptr = '\0';
217 	end = ++ptr;
218 	tmp = strtoul(ptr, &end, 10);
219 	if (end == ptr || tmp > UINT32_MAX)
220 		goto result_pwd2str;
221 	urid = (uint32_t)tmp;
222 
223 	/* We already have uid -- no need to call idmapd */
224 	if (be->db_type == NSS_AD_DB_PASSWD_BYUID)
225 		uid = argp->key.uid;
226 	else
227 		uid = be->uid;
228 
229 	/* Get primaryGroupID */
230 	pgid_v = adutils_getattr(entry, _PWD_PRIMARYGROUPID);
231 	if (pgid_v == NULL || pgid_v[0] == NULL || *pgid_v[0] == '\0')
232 		/*
233 		 * If primaryGroupID is not found then we request
234 		 * a GID to be mapped to the given user's objectSID
235 		 * (diagonal mapping) and use this GID as the primary
236 		 * GID for the entry.
237 		 */
238 		grid = urid;
239 	else {
240 		end = pgid_v[0];
241 		tmp = strtoul(pgid_v[0], &end, 10);
242 		if (end == pgid_v[0] || tmp > UINT32_MAX)
243 			goto result_pwd2str;
244 		grid = (uint32_t)tmp;
245 	}
246 
247 	/* Map group SID to GID using idmap service */
248 	if (idmap_get_gidbysid(ig, sid_v[0], grid, 0, &gid, &gstat) != 0)
249 		goto result_pwd2str;
250 	if (idmap_get_mappings(ig) != 0 || gstat != 0) {
251 		RESET_ERRNO();
252 		goto result_pwd2str;
253 	}
254 
255 	/* Get gecos, homedirectory and shell information if available */
256 	gecos_v = adutils_getattr(entry, _PWD_CN);
257 	if (gecos_v == NULL || gecos_v[0] == NULL || *gecos_v[0] == '\0')
258 		gecos_v = &NULL_STR;
259 
260 	homedir_v = adutils_getattr(entry, _PWD_HOMEDIRECTORY);
261 	if (homedir_v == NULL || homedir_v[0] == NULL || *homedir_v[0] == '\0')
262 		homedir = NULL_STR;
263 	else if ((homedir = process_homedir(homedir_v[0])) == NULL)
264 		homedir = NULL_STR;
265 
266 	shell_v = adutils_getattr(entry, _PWD_LOGINSHELL);
267 	if (shell_v == NULL || shell_v[0] == NULL || *shell_v[0] == '\0')
268 		shell_v = &NULL_STR;
269 
270 	if (update_buffer(be, argp, name_v[0], domain, uid, gid,
271 	    gecos_v[0], homedir, shell_v[0]) < 0)
272 		nss_result = NSS_STR_PARSE_ERANGE;
273 	else
274 		nss_result = NSS_STR_PARSE_SUCCESS;
275 
276 result_pwd2str:
277 	idmap_get_destroy(ig);
278 	(void) adutils_freeresult(&be->result);
279 	free(domain);
280 	if (homedir != NULL_STR && homedir_v != NULL &&
281 	    homedir != homedir_v[0])
282 		free(homedir);
283 	return ((int)nss_result);
284 }
285 
286 /*
287  * getbyname gets a passwd entry by winname. This function constructs an ldap
288  * search filter using the name invocation parameter and the getpwnam search
289  * filter defined. Once the filter is constructed, we search for a matching
290  * entry and marshal the data results into struct passwd for the frontend
291  * process. The function _nss_ad_passwd2ent performs the data marshaling.
292  */
293 
294 static nss_status_t
295 getbyname(ad_backend_ptr be, void *a)
296 {
297 	nss_XbyY_args_t	*argp = (nss_XbyY_args_t *)a;
298 	char		*searchfilter;
299 	char		name[SEARCHFILTERLEN];
300 	char		*dname;
301 	int		filterlen, namelen;
302 	int		flag;
303 	nss_status_t	stat;
304 	idmap_stat	idmaprc;
305 	uid_t		uid;
306 	gid_t		gid;
307 	int		is_user, is_wuser, try_idmap;
308 
309 	be->db_type = NSS_AD_DB_PASSWD_BYNAME;
310 
311 	/* Sanitize name so that it can be used in our LDAP filter */
312 	if (_ldap_filter_name(name, argp->key.name, sizeof (name)) != 0)
313 		return ((nss_status_t)NSS_NOTFOUND);
314 
315 	if ((dname = strchr(name, '@')) == NULL)
316 		return ((nss_status_t)NSS_NOTFOUND);
317 
318 	*dname = '\0';
319 	dname++;
320 
321 	/*
322 	 * Map the given name to UID using idmap service. If idmap
323 	 * call fails then this will save us doing AD discovery and
324 	 * AD lookup here.
325 	 */
326 	flag = (strcasecmp(dname, WK_DOMAIN) == 0) ?
327 	    IDMAP_REQ_FLG_WK_OR_LOCAL_SIDS_ONLY : 0;
328 	is_wuser = -1;
329 	is_user = 1;
330 	if (idmap_get_w2u_mapping(NULL, NULL, name,
331 	    dname, flag, &is_user, &is_wuser, &be->uid, NULL,
332 	    NULL, NULL) != IDMAP_SUCCESS) {
333 		RESET_ERRNO();
334 		return ((nss_status_t)NSS_NOTFOUND);
335 	}
336 
337 	/* If this is not a Well-Known SID then try AD lookup. */
338 	if (strcasecmp(dname, WK_DOMAIN) != 0) {
339 		/* Assemble filter using the given name */
340 		namelen = strlen(name);
341 		filterlen = snprintf(NULL, 0, _F_GETPWNAM, namelen, name) + 1;
342 		if ((searchfilter = (char *)malloc(filterlen)) == NULL)
343 			return ((nss_status_t)NSS_NOTFOUND);
344 		(void) snprintf(searchfilter, filterlen, _F_GETPWNAM,
345 		    namelen, name);
346 		stat = _nss_ad_lookup(be, argp, _PASSWD, searchfilter,
347 		    dname, &try_idmap);
348 		free(searchfilter);
349 
350 		if (!try_idmap)
351 			return (stat);
352 
353 	}
354 
355 	/*
356 	 * Either this is a Well-Known SID or AD lookup failed. Map
357 	 * the given name to GID using idmap service and construct
358 	 * the passwd entry.
359 	 */
360 	is_wuser = -1;
361 	is_user = 0; /* Map name to primary gid */
362 	idmaprc = idmap_get_w2u_mapping(NULL, NULL, name, dname,
363 	    flag, &is_user, &is_wuser, &gid, NULL, NULL, NULL);
364 	if (idmaprc != IDMAP_SUCCESS) {
365 		RESET_ERRNO();
366 		return ((nss_status_t)NSS_NOTFOUND);
367 	}
368 
369 	/* Create passwd(5) style string */
370 	if (update_buffer(be, argp, name, dname,
371 	    be->uid, gid, "", "", "") < 0)
372 		return ((nss_status_t)NSS_NOTFOUND);
373 
374 	/* Marshall the data, sanitize the return status and return */
375 	stat = _nss_ad_marshall_data(be, argp);
376 	return (_nss_ad_sanitize_status(be, argp, stat));
377 }
378 
379 
380 /*
381  * getbyuid gets a passwd entry by uid number. This function constructs an ldap
382  * search filter using the uid invocation parameter and the getpwuid search
383  * filter defined. Once the filter is constructed, we search for a matching
384  * entry and marshal the data results into struct passwd for the frontend
385  * process. The function _nss_ad_passwd2ent performs the data marshaling.
386  */
387 
388 static nss_status_t
389 getbyuid(ad_backend_ptr be, void *a)
390 {
391 	nss_XbyY_args_t		*argp = (nss_XbyY_args_t *)a;
392 	char			searchfilter[ADUTILS_MAXHEXBINSID + 14];
393 	char			*sidprefix = NULL;
394 	idmap_rid_t		rid;
395 	char			cbinsid[ADUTILS_MAXHEXBINSID + 1];
396 	char			*winname = NULL, *windomain = NULL;
397 	int			is_user, is_wuser;
398 	gid_t			gid;
399 	idmap_stat		idmaprc;
400 	int			ret, try_idmap;
401 	nss_status_t		stat;
402 
403 	be->db_type = NSS_AD_DB_PASSWD_BYUID;
404 
405 	stat = (nss_status_t)NSS_NOTFOUND;
406 
407 	/* nss_ad does not support non ephemeral uids */
408 	if (argp->key.uid <= MAXUID)
409 		goto out;
410 
411 	/* Map the given UID to a SID using the idmap service */
412 	if (idmap_get_u2w_mapping(&argp->key.uid, NULL, 0,
413 	    1, NULL, &sidprefix, &rid, &winname, &windomain,
414 	    NULL, NULL) != 0) {
415 		RESET_ERRNO();
416 		goto out;
417 	}
418 
419 	/*
420 	 * NULL winname implies a local SID or unresolvable SID both of
421 	 * which cannot be used to generated passwd(5) entry
422 	 */
423 	if (winname == NULL)
424 		goto out;
425 
426 	/* If this is not a Well-Known SID try AD lookup */
427 	if (windomain != NULL && strcasecmp(windomain, WK_DOMAIN) != 0) {
428 		if (adutils_txtsid2hexbinsid(sidprefix, &rid,
429 		    &cbinsid[0], sizeof (cbinsid)) != 0)
430 			goto out;
431 
432 		ret = snprintf(searchfilter, sizeof (searchfilter),
433 		    _F_GETPWUID, cbinsid);
434 		if (ret >= sizeof (searchfilter) || ret < 0)
435 			goto out;
436 
437 		stat = _nss_ad_lookup(be, argp, _PASSWD, searchfilter,
438 		    windomain, &try_idmap);
439 
440 		if (!try_idmap)
441 			goto out;
442 	}
443 
444 	/* Map winname to primary gid using idmap service */
445 	is_user = 0;
446 	is_wuser = -1;
447 	idmaprc = idmap_get_w2u_mapping(NULL, NULL,
448 	    winname, windomain, 0, &is_user, &is_wuser, &gid,
449 	    NULL, NULL, NULL);
450 
451 	if (idmaprc != IDMAP_SUCCESS) {
452 		RESET_ERRNO();
453 		goto out;
454 	}
455 
456 	/* Create passwd(5) style string */
457 	if (update_buffer(be, argp, winname, windomain,
458 	    argp->key.uid, gid, "", "", "") < 0)
459 		goto out;
460 
461 	/* Marshall the data, sanitize the return status and return */
462 	stat = _nss_ad_marshall_data(be, argp);
463 	stat = _nss_ad_sanitize_status(be, argp, stat);
464 
465 out:
466 	idmap_free(sidprefix);
467 	idmap_free(winname);
468 	idmap_free(windomain);
469 	return (stat);
470 }
471 
472 static ad_backend_op_t passwd_ops[] = {
473 	_nss_ad_destr,
474 	_nss_ad_endent,
475 	_nss_ad_setent,
476 	_nss_ad_getent,
477 	getbyname,
478 	getbyuid
479 };
480 
481 /*
482  * _nss_ad_passwd_constr is where life begins. This function calls the
483  * generic AD constructor function to define and build the abstract
484  * data types required to support AD operations.
485  */
486 
487 /*ARGSUSED0*/
488 nss_backend_t *
489 _nss_ad_passwd_constr(const char *dummy1, const char *dummy2,
490 			const char *dummy3)
491 {
492 
493 	return ((nss_backend_t *)_nss_ad_constr(passwd_ops,
494 	    sizeof (passwd_ops)/sizeof (passwd_ops[0]),
495 	    _PASSWD, pwd_attrs, _nss_ad_passwd2str));
496 }
497