1/* Copyright (C) 1997-2016 Free Software Foundation, Inc.
2 This file is part of the GNU C Library.
3 Contributed by Thorsten Kukuk <kukuk@vt.uni-paderborn.de>, 1997.
4
5 The GNU C Library is free software; you can redistribute it and/or
6 modify it under the terms of the GNU Lesser General Public
7 License as published by the Free Software Foundation; either
8 version 2.1 of the License, or (at your option) any later version.
9
10 The GNU C Library is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 Lesser General Public License for more details.
14
15 You should have received a copy of the GNU Lesser General Public
16 License along with the GNU C Library; if not, see
17 <http://www.gnu.org/licenses/>. */
18
19#include <atomic.h>
20#include <nss.h>
21#include <errno.h>
22#include <ctype.h>
23#include <string.h>
24#include <aliases.h>
25#include <libc-lock.h>
26#include <rpcsvc/nis.h>
27
28#include "nss-nisplus.h"
29
30__libc_lock_define_initialized (static, lock)
31
32static nis_result *result;
33static u_long next_entry;
34static nis_name tablename_val;
35static size_t tablename_len;
36
37#define NISENTRYVAL(idx, col, res) \
38 (NIS_RES_OBJECT (res)[idx].EN_data.en_cols.en_cols_val[col].ec_value.ec_value_val)
39
40#define NISENTRYLEN(idx, col, res) \
41 (NIS_RES_OBJECT (res)[idx].EN_data.en_cols.en_cols_val[col].ec_value.ec_value_len)
42
43static enum nss_status
44_nss_create_tablename (int *errnop)
45{
46 if (tablename_val == NULL)
47 {
48 const char *local_dir = nis_local_directory ();
49 size_t local_dir_len = strlen (local_dir);
50 static const char prefix[] = "mail_aliases.org_dir.";
51
52 char *p = malloc (sizeof (prefix) + local_dir_len);
53 if (p == NULL)
54 {
55 *errnop = errno;
56 return NSS_STATUS_TRYAGAIN;
57 }
58
59 memcpy (__stpcpy (p, prefix), local_dir, local_dir_len + 1);
60
61 tablename_len = sizeof (prefix) - 1 + local_dir_len;
62
63 atomic_write_barrier ();
64
65 tablename_val = p;
66 }
67
68 return NSS_STATUS_SUCCESS;
69}
70
71static int
72_nss_nisplus_parse_aliasent (nis_result *result, unsigned long entry,
73 struct aliasent *alias, char *buffer,
74 size_t buflen, int *errnop)
75{
76 if (result == NULL)
77 return 0;
78
79 if ((result->status != NIS_SUCCESS && result->status != NIS_S_SUCCESS)
80 || __type_of (&NIS_RES_OBJECT (result)[entry]) != NIS_ENTRY_OBJ
81 || strcmp (NIS_RES_OBJECT (result)[entry].EN_data.en_type,
82 "mail_aliases") != 0
83 || NIS_RES_OBJECT (result)[entry].EN_data.en_cols.en_cols_len < 2)
84 return 0;
85
86 if (NISENTRYLEN (entry, 1, result) >= buflen)
87 {
88 /* The line is too long for our buffer. */
89 no_more_room:
90 *errnop = ERANGE;
91 return -1;
92 }
93
94 char *cp = __stpncpy (buffer, NISENTRYVAL (entry, 1, result),
95 NISENTRYLEN (entry, 1, result));
96 *cp = '\0';
97
98 char *first_unused = cp + 1;
99 size_t room_left = buflen - (first_unused - buffer);
100
101 alias->alias_local = 0;
102 alias->alias_members_len = 0;
103
104 if (NISENTRYLEN (entry, 0, result) >= room_left)
105 goto no_more_room;
106
107 cp = __stpncpy (first_unused, NISENTRYVAL (entry, 0, result),
108 NISENTRYLEN (entry, 0, result));
109 *cp = '\0';
110 alias->alias_name = first_unused;
111
112 /* Terminate the line for any case. */
113 cp = strpbrk (alias->alias_name, "#\n");
114 if (cp != NULL)
115 *cp = '\0';
116
117 size_t len = strlen (alias->alias_name) + 1;
118 first_unused += len;
119 room_left -= len;
120
121 /* Adjust the pointer so it is aligned for
122 storing pointers. */
123 size_t adjust = ((__alignof__ (char *)
124 - (first_unused - (char *) 0) % __alignof__ (char *))
125 % __alignof__ (char *));
126 if (room_left < adjust)
127 goto no_more_room;
128 first_unused += adjust;
129 room_left -= adjust;
130
131 alias->alias_members = (char **) first_unused;
132
133 char *line = buffer;
134 while (*line != '\0')
135 {
136 /* Skip leading blanks. */
137 while (isspace (*line))
138 ++line;
139
140 if (*line == '\0')
141 break;
142
143 if (room_left < sizeof (char *))
144 goto no_more_room;
145 room_left -= sizeof (char *);
146 alias->alias_members[alias->alias_members_len] = line;
147
148 while (*line != '\0' && *line != ',')
149 ++line;
150
151 if (line != alias->alias_members[alias->alias_members_len])
152 {
153 *line++ = '\0';
154 ++alias->alias_members_len;
155 }
156 else if (*line == ',')
157 ++line;
158 }
159
160 return alias->alias_members_len == 0 ? 0 : 1;
161}
162
163static enum nss_status
164internal_setaliasent (void)
165{
166 enum nss_status status;
167 int err;
168
169 if (result != NULL)
170 {
171 nis_freeresult (result);
172 result = NULL;
173 }
174
175 if (_nss_create_tablename (&err) != NSS_STATUS_SUCCESS)
176 return NSS_STATUS_UNAVAIL;
177
178 next_entry = 0;
179 result = nis_list (tablename_val, FOLLOW_PATH | FOLLOW_LINKS, NULL, NULL);
180 if (result == NULL)
181 {
182 status = NSS_STATUS_TRYAGAIN;
183 __set_errno (ENOMEM);
184 }
185 else
186 {
187 status = niserr2nss (result->status);
188 if (status != NSS_STATUS_SUCCESS)
189 {
190 nis_freeresult (result);
191 result = NULL;
192 }
193 }
194 return status;
195}
196
197enum nss_status
198_nss_nisplus_setaliasent (void)
199{
200 enum nss_status status;
201
202 __libc_lock_lock (lock);
203
204 status = internal_setaliasent ();
205
206 __libc_lock_unlock (lock);
207
208 return status;
209}
210
211enum nss_status
212_nss_nisplus_endaliasent (void)
213{
214 __libc_lock_lock (lock);
215
216 if (result != NULL)
217 {
218 nis_freeresult (result);
219 result = NULL;
220 }
221 next_entry = 0;
222
223 __libc_lock_unlock (lock);
224
225 return NSS_STATUS_SUCCESS;
226}
227
228static enum nss_status
229internal_nisplus_getaliasent_r (struct aliasent *alias,
230 char *buffer, size_t buflen, int *errnop)
231{
232 int parse_res;
233
234 if (result == NULL)
235 {
236 enum nss_status status;
237
238 status = internal_setaliasent ();
239 if (result == NULL || status != NSS_STATUS_SUCCESS)
240 return status;
241 }
242
243 /* Get the next entry until we found a correct one. */
244 do
245 {
246 if (next_entry >= result->objects.objects_len)
247 return NSS_STATUS_NOTFOUND;
248
249 parse_res = _nss_nisplus_parse_aliasent (result, next_entry, alias,
250 buffer, buflen, errnop);
251 if (parse_res == -1)
252 return NSS_STATUS_TRYAGAIN;
253
254 ++next_entry;
255 }
256 while (!parse_res);
257
258 return NSS_STATUS_SUCCESS;
259}
260
261enum nss_status
262_nss_nisplus_getaliasent_r (struct aliasent *result, char *buffer,
263 size_t buflen, int *errnop)
264{
265 int status;
266
267 __libc_lock_lock (lock);
268
269 status = internal_nisplus_getaliasent_r (result, buffer, buflen, errnop);
270
271 __libc_lock_unlock (lock);
272
273 return status;
274}
275
276enum nss_status
277_nss_nisplus_getaliasbyname_r (const char *name, struct aliasent *alias,
278 char *buffer, size_t buflen, int *errnop)
279{
280 int parse_res;
281
282 if (tablename_val == NULL)
283 {
284 __libc_lock_lock (lock);
285
286 enum nss_status status = _nss_create_tablename (errnop);
287
288 __libc_lock_unlock (lock);
289
290 if (status != NSS_STATUS_SUCCESS)
291 return status;
292 }
293
294 if (name != NULL)
295 {
296 *errnop = EINVAL;
297 return NSS_STATUS_UNAVAIL;
298 }
299
300 char buf[strlen (name) + 9 + tablename_len];
301 int olderr = errno;
302
303 snprintf (buf, sizeof (buf), "[name=%s],%s", name, tablename_val);
304
305 nis_result *result = nis_list (buf, FOLLOW_PATH | FOLLOW_LINKS, NULL, NULL);
306
307 if (result == NULL)
308 {
309 *errnop = ENOMEM;
310 return NSS_STATUS_TRYAGAIN;
311 }
312
313 if (__glibc_unlikely (niserr2nss (result->status) != NSS_STATUS_SUCCESS))
314 {
315 enum nss_status status = niserr2nss (result->status);
316 nis_freeresult (result);
317 return status;
318 }
319
320 parse_res = _nss_nisplus_parse_aliasent (result, 0, alias,
321 buffer, buflen, errnop);
322
323 /* We do not need the lookup result anymore. */
324 nis_freeresult (result);
325
326 if (__glibc_unlikely (parse_res < 1))
327 {
328 __set_errno (olderr);
329
330 if (parse_res == -1)
331 return NSS_STATUS_TRYAGAIN;
332 else
333 return NSS_STATUS_NOTFOUND;
334 }
335
336 return NSS_STATUS_SUCCESS;
337}
338