summaryrefslogtreecommitdiffstats
path: root/source3/auth/user_util.c
blob: d982c746c6bf4b0beeca6bbd6ab2a5fdb67e9083 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
/*
   Unix SMB/CIFS implementation.
   Username handling
   Copyright (C) Andrew Tridgell 1992-1998
   Copyright (C) Jeremy Allison 1997-2001.
   Copyright (C) Volker Lendecke 2006

   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; either version 3 of the License, or
   (at your option) any later version.

   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with this program.  If not, see <http://www.gnu.org/licenses/>.
*/

#include "includes.h"
#include "system/filesys.h"
#include "auth.h"

/*******************************************************************
 Map a username from a dos name to a unix name by looking in the username
 map. Note that this modifies the name in place.
 This is the main function that should be called *once* on
 any incoming or new username - in order to canonicalize the name.
 This is being done to de-couple the case conversions from the user mapping
 function. Previously, the map_username was being called
 every time Get_Pwnam_alloc was called.
 Returns True if username was changed, false otherwise.
********************************************************************/

static char *last_from = NULL;
static char *last_to = NULL;

static const char *get_last_from(void)
{
	if (!last_from) {
		return "";
	}
	return last_from;
}

static const char *get_last_to(void)
{
	if (!last_to) {
		return "";
	}
	return last_to;
}

static bool set_last_from_to(const char *from, const char *to)
{
	char *orig_from = last_from;
	char *orig_to = last_to;

	last_from = SMB_STRDUP(from);
	last_to = SMB_STRDUP(to);

	SAFE_FREE(orig_from);
	SAFE_FREE(orig_to);

	if (!last_from || !last_to) {
		SAFE_FREE(last_from);
		SAFE_FREE(last_to);
		return false;
	}
	return true;
}

static char *skip_space(char *s)
{
	while (isspace((int)(*s))) {
		s += 1;
	}
	return s;
}

static bool fetch_map_from_gencache(TALLOC_CTX *ctx,
			const char *user_in,
			char **p_user_out)
{
	char *key, *value;
	bool found;

	if (lp_username_map_cache_time() == 0) {
		return false;
	}

	key = talloc_asprintf_strupper_m(ctx, "USERNAME_MAP/%s",
					 user_in);
	if (key == NULL) {
		return false;
	}
	found = gencache_get(key, &value, NULL);
	TALLOC_FREE(key);
	if (!found) {
		return false;
	}
	TALLOC_FREE(*p_user_out);
	*p_user_out = talloc_strdup(ctx, value);
	SAFE_FREE(value);
	if (!*p_user_out) {
		return false;
	}
	return true;
}

static void store_map_in_gencache(TALLOC_CTX *ctx, const char *from, const char *to)
{
	char *key;
	int cache_time = lp_username_map_cache_time();

	if (cache_time == 0) {
		return;
	}

	key = talloc_asprintf_strupper_m(ctx, "USERNAME_MAP/%s",
					 from);
        if (key == NULL) {
                return;
        }
	gencache_set(key, to, cache_time + time(NULL));
	TALLOC_FREE(key);
}

/****************************************************************************
 Check if a user is in a netgroup user list. If at first we don't succeed,
 try lower case.
****************************************************************************/

bool user_in_netgroup(TALLOC_CTX *ctx, const char *user, const char *ngname)
{
#ifdef HAVE_NETGROUP
	static char *my_yp_domain = NULL;
	char *lowercase_user = NULL;

	if (my_yp_domain == NULL) {
		yp_get_default_domain(&my_yp_domain);
	}

	if (my_yp_domain == NULL) {
		DEBUG(5,("Unable to get default yp domain, "
			"let's try without specifying it\n"));
	}

	DEBUG(5,("looking for user %s of domain %s in netgroup %s\n",
		user, my_yp_domain?my_yp_domain:"(ANY)", ngname));

	if (innetgr(ngname, NULL, user, my_yp_domain)) {
		DEBUG(5,("user_in_netgroup: Found\n"));
		return true;
	}

	/*
	 * Ok, innetgr is case sensitive. Try once more with lowercase
	 * just in case. Attempt to fix #703. JRA.
	 */
	lowercase_user = talloc_strdup(ctx, user);
	if (!lowercase_user) {
		return false;
	}
	strlower_m(lowercase_user);

	if (strcmp(user,lowercase_user) == 0) {
		/* user name was already lower case! */
		return false;
	}

	DEBUG(5,("looking for user %s of domain %s in netgroup %s\n",
		lowercase_user, my_yp_domain?my_yp_domain:"(ANY)", ngname));

	if (innetgr(ngname, NULL, lowercase_user, my_yp_domain)) {
		DEBUG(5,("user_in_netgroup: Found\n"));
		return true;
	}
#endif /* HAVE_NETGROUP */
	return false;
}

/****************************************************************************
 Check if a user is in a user list - can check combinations of UNIX
 and netgroup lists.
****************************************************************************/

bool user_in_list(TALLOC_CTX *ctx, const char *user,const char **list)
{
	if (!list || !*list)
		return False;

	DEBUG(10,("user_in_list: checking user %s in list\n", user));

	while (*list) {

		DEBUG(10,("user_in_list: checking user |%s| against |%s|\n",
			  user, *list));

		/*
		 * Check raw username.
		 */
		if (strequal(user, *list))
			return(True);

		/*
		 * Now check to see if any combination
		 * of UNIX and netgroups has been specified.
		 */

		if(**list == '@') {
			/*
			 * Old behaviour. Check netgroup list
			 * followed by UNIX list.
			 */
			if(user_in_netgroup(ctx, user, *list +1))
				return True;
			if(user_in_group(user, *list +1))
				return True;
		} else if (**list == '+') {

			if((*(*list +1)) == '&') {
				/*
				 * Search UNIX list followed by netgroup.
				 */
				if(user_in_group(user, *list +2))
					return True;
				if(user_in_netgroup(ctx, user, *list +2))
					return True;

			} else {

				/*
				 * Just search UNIX list.
				 */

				if(user_in_group(user, *list +1))
					return True;
			}

		} else if (**list == '&') {

			if(*(*list +1) == '+') {
				/*
				 * Search netgroup list followed by UNIX list.
				 */
				if(user_in_netgroup(ctx, user, *list +2))
					return True;
				if(user_in_group(user, *list +2))
					return True;
			} else {
				/*
				 * Just search netgroup list.
				 */
				if(user_in_netgroup(ctx, user, *list +1))
					return True;
			}
		}

		list++;
	}
	return(False);
}

bool map_username(TALLOC_CTX *ctx, const char *user_in, char **p_user_out)
{
	XFILE *f;
	char *mapfile = lp_username_map();
	char *s;
	char buf[512];
	bool mapped_user = False;
	char *cmd = lp_username_map_script();

	*p_user_out = NULL;

	if (!user_in)
		return false;

	/* Initially make a copy of the incoming name. */
	*p_user_out = talloc_strdup(ctx, user_in);
	if (!*p_user_out) {
		return false;
	}

	if (strequal(user_in,get_last_to()))
		return false;

	if (strequal(user_in,get_last_from())) {
		DEBUG(3,("Mapped user %s to %s\n",user_in,get_last_to()));
		TALLOC_FREE(*p_user_out);
		*p_user_out = talloc_strdup(ctx, get_last_to());
		return true;
	}

	if (fetch_map_from_gencache(ctx, user_in, p_user_out)) {
		return true;
	}

	/* first try the username map script */

	if ( *cmd ) {
		char **qlines;
		char *command = NULL;
		int numlines, ret, fd;

		command = talloc_asprintf(ctx,
					"%s \"%s\"",
					cmd,
					user_in);
		if (!command) {
			return false;
		}

		DEBUG(10,("Running [%s]\n", command));
		ret = smbrun(command, &fd);
		DEBUGADD(10,("returned [%d]\n", ret));

		TALLOC_FREE(command);

		if ( ret != 0 ) {
			if (fd != -1)
				close(fd);
			return False;
		}

		numlines = 0;
		qlines = fd_lines_load(fd, &numlines, 0, ctx);
		DEBUGADD(10,("Lines returned = [%d]\n", numlines));
		close(fd);

		/* should be either no lines or a single line with the mapped username */

		if (numlines && qlines) {
			DEBUG(3,("Mapped user %s to %s\n", user_in, qlines[0] ));
			set_last_from_to(user_in, qlines[0]);
			store_map_in_gencache(ctx, user_in, qlines[0]);
			TALLOC_FREE(*p_user_out);
			*p_user_out = talloc_strdup(ctx, qlines[0]);
			if (!*p_user_out) {
				return false;
			}
		}

		TALLOC_FREE(qlines);

		return numlines != 0;
	}

	/* ok.  let's try the mapfile */
	if (!*mapfile)
		return False;

	f = x_fopen(mapfile,O_RDONLY, 0);
	if (!f) {
		DEBUG(0,("can't open username map %s. Error %s\n",mapfile, strerror(errno) ));
		return False;
	}

	DEBUG(4,("Scanning username map %s\n",mapfile));

	while((s=fgets_slash(buf,sizeof(buf),f))!=NULL) {
		char *unixname = s;
		char *dosname = strchr_m(unixname,'=');
		char **dosuserlist;
		bool return_if_mapped = False;

		if (!dosname)
			continue;

		*dosname++ = 0;

		unixname = skip_space(unixname);

		if ('!' == *unixname) {
			return_if_mapped = True;
			unixname = skip_space(unixname+1);
		}

		if (!*unixname || strchr_m("#;",*unixname))
			continue;

		{
			int l = strlen(unixname);
			while (l && isspace((int)unixname[l-1])) {
				unixname[l-1] = 0;
				l--;
			}
		}

		/* skip lines like 'user = ' */

		dosuserlist = str_list_make_v3(ctx, dosname, NULL);
		if (!dosuserlist) {
			DEBUG(0,("Bad username map entry.  Unable to build user list.  Ignoring.\n"));
			continue;
		}

		if (strchr_m(dosname,'*') ||
		    user_in_list(ctx, user_in, (const char **)dosuserlist)) {
			DEBUG(3,("Mapped user %s to %s\n",user_in,unixname));
			mapped_user = True;

			set_last_from_to(user_in, unixname);
			store_map_in_gencache(ctx, user_in, unixname);
			TALLOC_FREE(*p_user_out);
			*p_user_out = talloc_strdup(ctx, unixname);
			if (!*p_user_out) {
				TALLOC_FREE(dosuserlist);
				x_fclose(f);
				return false;
			}

			if ( return_if_mapped ) {
				TALLOC_FREE(dosuserlist);
				x_fclose(f);
				return True;
			}
		}

		TALLOC_FREE(dosuserlist);
	}

	x_fclose(f);

	/*
	 * Setup the last_from and last_to as an optimization so
	 * that we don't scan the file again for the same user.
	 */

	set_last_from_to(user_in, user_in);
	store_map_in_gencache(ctx, user_in, user_in);

	return mapped_user;
}