1 /* set-mode-acl.c - set access control list equivalent to a mode
2
3 Copyright (C) 2002-2003, 2005-2009 Free Software Foundation, Inc.
4
5 This program is free software: you can redistribute it and/or modify
6 it under the terms of the GNU General Public License as published by
7 the Free Software Foundation; either version 3 of the License, or
8 (at your option) any later version.
9
10 This program 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
13 GNU General Public License for more details.
14
15 You should have received a copy of the GNU General Public License
16 along with this program. If not, see <http://www.gnu.org/licenses/>.
17
18 Written by Paul Eggert and Andreas Gruenbacher, and Bruno Haible. */
19
20 #include <config.h>
21
22 #include "acl.h"
23
24 #include "acl-internal.h"
25
26 #include "gettext.h"
27 #define _(msgid) gettext (msgid)
28
29
30 /* If DESC is a valid file descriptor use fchmod to change the
31 file's mode to MODE on systems that have fchown. On systems
32 that don't have fchown and if DESC is invalid, use chown on
33 NAME instead.
34 Return 0 if successful. Return -1 and set errno upon failure. */
35
36 int
chmod_or_fchmod(const char * name,int desc,mode_t mode)37 chmod_or_fchmod (const char *name, int desc, mode_t mode)
38 {
39 if (HAVE_FCHMOD && desc != -1)
40 return fchmod (desc, mode);
41 else
42 return chmod (name, mode);
43 }
44
45 /* Set the access control lists of a file. If DESC is a valid file
46 descriptor, use file descriptor operations where available, else use
47 filename based operations on NAME. If access control lists are not
48 available, fchmod the target file to MODE. Also sets the
49 non-permission bits of the destination file (S_ISUID, S_ISGID, S_ISVTX)
50 to those from MODE if any are set.
51 Return 0 if successful. Return -1 and set errno upon failure. */
52
53 int
qset_acl(char const * name,int desc,mode_t mode)54 qset_acl (char const *name, int desc, mode_t mode)
55 {
56 #if USE_ACL
57 # if HAVE_ACL_GET_FILE
58 /* POSIX 1003.1e draft 17 (abandoned) specific version. */
59 /* Linux, FreeBSD, MacOS X, IRIX, Tru64 */
60 # if MODE_INSIDE_ACL
61 /* Linux, FreeBSD, IRIX, Tru64 */
62
63 /* We must also have acl_from_text and acl_delete_def_file.
64 (acl_delete_def_file could be emulated with acl_init followed
65 by acl_set_file, but acl_set_file with an empty acl is
66 unspecified.) */
67
68 # ifndef HAVE_ACL_FROM_TEXT
69 # error Must have acl_from_text (see POSIX 1003.1e draft 17).
70 # endif
71 # ifndef HAVE_ACL_DELETE_DEF_FILE
72 # error Must have acl_delete_def_file (see POSIX 1003.1e draft 17).
73 # endif
74
75 acl_t acl;
76 int ret;
77
78 if (HAVE_ACL_FROM_MODE) /* Linux */
79 {
80 acl = acl_from_mode (mode);
81 if (!acl)
82 return -1;
83 }
84 else /* FreeBSD, IRIX, Tru64 */
85 {
86 /* If we were to create the ACL using the functions acl_init(),
87 acl_create_entry(), acl_set_tag_type(), acl_set_qualifier(),
88 acl_get_permset(), acl_clear_perm[s](), acl_add_perm(), we
89 would need to create a qualifier. I don't know how to do this.
90 So create it using acl_from_text(). */
91
92 # if HAVE_ACL_FREE_TEXT /* Tru64 */
93 char acl_text[] = "u::---,g::---,o::---,";
94 # else /* FreeBSD, IRIX */
95 char acl_text[] = "u::---,g::---,o::---";
96 # endif
97
98 if (mode & S_IRUSR) acl_text[ 3] = 'r';
99 if (mode & S_IWUSR) acl_text[ 4] = 'w';
100 if (mode & S_IXUSR) acl_text[ 5] = 'x';
101 if (mode & S_IRGRP) acl_text[10] = 'r';
102 if (mode & S_IWGRP) acl_text[11] = 'w';
103 if (mode & S_IXGRP) acl_text[12] = 'x';
104 if (mode & S_IROTH) acl_text[17] = 'r';
105 if (mode & S_IWOTH) acl_text[18] = 'w';
106 if (mode & S_IXOTH) acl_text[19] = 'x';
107
108 acl = acl_from_text (acl_text);
109 if (!acl)
110 return -1;
111 }
112 if (HAVE_ACL_SET_FD && desc != -1)
113 ret = acl_set_fd (desc, acl);
114 else
115 ret = acl_set_file (name, ACL_TYPE_ACCESS, acl);
116 if (ret != 0)
117 {
118 int saved_errno = errno;
119 acl_free (acl);
120
121 if (ACL_NOT_WELL_SUPPORTED (errno))
122 return chmod_or_fchmod (name, desc, mode);
123 else
124 {
125 errno = saved_errno;
126 return -1;
127 }
128 }
129 else
130 acl_free (acl);
131
132 if (S_ISDIR (mode) && acl_delete_def_file (name))
133 return -1;
134
135 if (mode & (S_ISUID | S_ISGID | S_ISVTX))
136 {
137 /* We did not call chmod so far, so the special bits have not yet
138 been set. */
139 return chmod_or_fchmod (name, desc, mode);
140 }
141 return 0;
142
143 # else /* !MODE_INSIDE_ACL */
144 /* MacOS X */
145
146 # if !HAVE_ACL_TYPE_EXTENDED
147 # error Must have ACL_TYPE_EXTENDED
148 # endif
149
150 /* On MacOS X, acl_get_file (name, ACL_TYPE_ACCESS)
151 and acl_get_file (name, ACL_TYPE_DEFAULT)
152 always return NULL / EINVAL. You have to use
153 acl_get_file (name, ACL_TYPE_EXTENDED)
154 or acl_get_fd (open (name, ...))
155 to retrieve an ACL.
156 On the other hand,
157 acl_set_file (name, ACL_TYPE_ACCESS, acl)
158 and acl_set_file (name, ACL_TYPE_DEFAULT, acl)
159 have the same effect as
160 acl_set_file (name, ACL_TYPE_EXTENDED, acl):
161 Each of these calls sets the file's ACL. */
162
163 acl_t acl;
164 int ret;
165
166 /* Remove the ACL if the file has ACLs. */
167 if (HAVE_ACL_GET_FD && desc != -1)
168 acl = acl_get_fd (desc);
169 else
170 acl = acl_get_file (name, ACL_TYPE_EXTENDED);
171 if (acl)
172 {
173 acl_free (acl);
174
175 acl = acl_init (0);
176 if (acl)
177 {
178 if (HAVE_ACL_SET_FD && desc != -1)
179 ret = acl_set_fd (desc, acl);
180 else
181 ret = acl_set_file (name, ACL_TYPE_EXTENDED, acl);
182 if (ret != 0)
183 {
184 int saved_errno = errno;
185
186 acl_free (acl);
187
188 if (ACL_NOT_WELL_SUPPORTED (saved_errno))
189 return chmod_or_fchmod (name, desc, mode);
190 else
191 {
192 errno = saved_errno;
193 return -1;
194 }
195 }
196 acl_free (acl);
197 }
198 }
199
200 /* Since !MODE_INSIDE_ACL, we have to call chmod explicitly. */
201 return chmod_or_fchmod (name, desc, mode);
202 # endif
203
204 # elif HAVE_ACL && defined GETACLCNT /* Solaris, Cygwin, not HP-UX */
205
206 # if defined ACL_NO_TRIVIAL
207 /* Solaris 10 (newer version), which has additional API declared in
208 <sys/acl.h> (acl_t) and implemented in libsec (acl_set, acl_trivial,
209 acl_fromtext, ...). */
210
211 acl_t *aclp;
212 char acl_text[] = "user::---,group::---,mask:---,other:---";
213 int ret;
214 int saved_errno;
215
216 if (mode & S_IRUSR) acl_text[ 6] = 'r';
217 if (mode & S_IWUSR) acl_text[ 7] = 'w';
218 if (mode & S_IXUSR) acl_text[ 8] = 'x';
219 if (mode & S_IRGRP) acl_text[17] = acl_text[26] = 'r';
220 if (mode & S_IWGRP) acl_text[18] = acl_text[27] = 'w';
221 if (mode & S_IXGRP) acl_text[19] = acl_text[28] = 'x';
222 if (mode & S_IROTH) acl_text[36] = 'r';
223 if (mode & S_IWOTH) acl_text[37] = 'w';
224 if (mode & S_IXOTH) acl_text[38] = 'x';
225
226 if (acl_fromtext (acl_text, &aclp) != 0)
227 {
228 errno = ENOMEM;
229 return -1;
230 }
231
232 ret = (desc < 0 ? acl_set (name, aclp) : facl_set (desc, aclp));
233 saved_errno = errno;
234 acl_free (aclp);
235 if (ret < 0)
236 {
237 if (saved_errno == ENOSYS)
238 return chmod_or_fchmod (name, desc, mode);
239 errno = saved_errno;
240 return -1;
241 }
242
243 if (mode & (S_ISUID | S_ISGID | S_ISVTX))
244 {
245 /* We did not call chmod so far, so the special bits have not yet
246 been set. */
247 return chmod_or_fchmod (name, desc, mode);
248 }
249 return 0;
250
251 # else /* Solaris, Cygwin, general case */
252
253 # ifdef ACE_GETACL
254 /* Solaris also has a different variant of ACLs, used in ZFS and NFSv4
255 file systems (whereas the other ones are used in UFS file systems). */
256
257 /* The flags in the ace_t structure changed in a binary incompatible way
258 when ACL_NO_TRIVIAL etc. were introduced in <sys/acl.h> version 1.15.
259 How to distinguish the two conventions at runtime?
260 We fetch the existing ACL. In the old convention, usually three ACEs have
261 a_flags = ACE_OWNER / ACE_GROUP / ACE_OTHER, in the range 0x0100..0x0400.
262 In the new convention, these values are not used. */
263 int convention;
264
265 {
266 int count;
267 ace_t *entries;
268
269 for (;;)
270 {
271 if (desc != -1)
272 count = facl (desc, ACE_GETACLCNT, 0, NULL);
273 else
274 count = acl (name, ACE_GETACLCNT, 0, NULL);
275 if (count <= 0)
276 {
277 convention = -1;
278 break;
279 }
280 entries = (ace_t *) malloc (count * sizeof (ace_t));
281 if (entries == NULL)
282 {
283 errno = ENOMEM;
284 return -1;
285 }
286 if ((desc != -1
287 ? facl (desc, ACE_GETACL, count, entries)
288 : acl (name, ACE_GETACL, count, entries))
289 == count)
290 {
291 int i;
292
293 convention = 0;
294 for (i = 0; i < count; i++)
295 if (entries[i].a_flags & (ACE_OWNER | ACE_GROUP | ACE_OTHER))
296 {
297 convention = 1;
298 break;
299 }
300 free (entries);
301 break;
302 }
303 /* Huh? The number of ACL entries changed since the last call.
304 Repeat. */
305 free (entries);
306 }
307 }
308
309 if (convention >= 0)
310 {
311 ace_t entries[3];
312 int ret;
313
314 if (convention)
315 {
316 /* Running on Solaris 10. */
317 entries[0].a_type = ALLOW;
318 entries[0].a_flags = ACE_OWNER;
319 entries[0].a_who = 0; /* irrelevant */
320 entries[0].a_access_mask = (mode >> 6) & 7;
321 entries[1].a_type = ALLOW;
322 entries[1].a_flags = ACE_GROUP;
323 entries[1].a_who = 0; /* irrelevant */
324 entries[1].a_access_mask = (mode >> 3) & 7;
325 entries[2].a_type = ALLOW;
326 entries[2].a_flags = ACE_OTHER;
327 entries[2].a_who = 0;
328 entries[2].a_access_mask = mode & 7;
329 }
330 else
331 {
332 /* Running on Solaris 10 (newer version) or Solaris 11. */
333 entries[0].a_type = ACE_ACCESS_ALLOWED_ACE_TYPE;
334 entries[0].a_flags = NEW_ACE_OWNER;
335 entries[0].a_who = 0; /* irrelevant */
336 entries[0].a_access_mask =
337 (mode & 0400 ? NEW_ACE_READ_DATA : 0)
338 | (mode & 0200 ? NEW_ACE_WRITE_DATA : 0)
339 | (mode & 0100 ? NEW_ACE_EXECUTE : 0);
340 entries[1].a_type = ACE_ACCESS_ALLOWED_ACE_TYPE;
341 entries[1].a_flags = NEW_ACE_GROUP | NEW_ACE_IDENTIFIER_GROUP;
342 entries[1].a_who = 0; /* irrelevant */
343 entries[1].a_access_mask =
344 (mode & 0040 ? NEW_ACE_READ_DATA : 0)
345 | (mode & 0020 ? NEW_ACE_WRITE_DATA : 0)
346 | (mode & 0010 ? NEW_ACE_EXECUTE : 0);
347 entries[2].a_type = ACE_ACCESS_ALLOWED_ACE_TYPE;
348 entries[2].a_flags = ACE_EVERYONE;
349 entries[2].a_who = 0;
350 entries[2].a_access_mask =
351 (mode & 0004 ? NEW_ACE_READ_DATA : 0)
352 | (mode & 0002 ? NEW_ACE_WRITE_DATA : 0)
353 | (mode & 0001 ? NEW_ACE_EXECUTE : 0);
354 }
355 if (desc != -1)
356 ret = facl (desc, ACE_SETACL,
357 sizeof (entries) / sizeof (ace_t), entries);
358 else
359 ret = acl (name, ACE_SETACL,
360 sizeof (entries) / sizeof (ace_t), entries);
361 if (ret < 0 && errno != EINVAL && errno != ENOTSUP)
362 {
363 if (errno == ENOSYS)
364 return chmod_or_fchmod (name, desc, mode);
365 return -1;
366 }
367 }
368 # endif
369
370 {
371 aclent_t entries[3];
372 int ret;
373
374 entries[0].a_type = USER_OBJ;
375 entries[0].a_id = 0; /* irrelevant */
376 entries[0].a_perm = (mode >> 6) & 7;
377 entries[1].a_type = GROUP_OBJ;
378 entries[1].a_id = 0; /* irrelevant */
379 entries[1].a_perm = (mode >> 3) & 7;
380 entries[2].a_type = OTHER_OBJ;
381 entries[2].a_id = 0;
382 entries[2].a_perm = mode & 7;
383
384 if (desc != -1)
385 ret = facl (desc, SETACL, sizeof (entries) / sizeof (aclent_t), entries);
386 else
387 ret = acl (name, SETACL, sizeof (entries) / sizeof (aclent_t), entries);
388 if (ret < 0)
389 {
390 if (errno == ENOSYS)
391 return chmod_or_fchmod (name, desc, mode);
392 return -1;
393 }
394 }
395
396 if (!MODE_INSIDE_ACL || (mode & (S_ISUID | S_ISGID | S_ISVTX)))
397 {
398 /* We did not call chmod so far, so the special bits have not yet
399 been set. */
400 return chmod_or_fchmod (name, desc, mode);
401 }
402 return 0;
403
404 # endif
405
406 # elif HAVE_GETACL /* HP-UX */
407
408 struct stat statbuf;
409 struct acl_entry entries[3];
410 int ret;
411
412 if (desc != -1)
413 ret = fstat (desc, &statbuf);
414 else
415 ret = stat (name, &statbuf);
416 if (ret < 0)
417 return -1;
418
419 entries[0].uid = statbuf.st_uid;
420 entries[0].gid = ACL_NSGROUP;
421 entries[0].mode = (mode >> 6) & 7;
422 entries[1].uid = ACL_NSUSER;
423 entries[1].gid = statbuf.st_gid;
424 entries[1].mode = (mode >> 3) & 7;
425 entries[2].uid = ACL_NSUSER;
426 entries[2].gid = ACL_NSGROUP;
427 entries[2].mode = mode & 7;
428
429 if (desc != -1)
430 ret = fsetacl (desc, sizeof (entries) / sizeof (struct acl_entry), entries);
431 else
432 ret = setacl (name, sizeof (entries) / sizeof (struct acl_entry), entries);
433 if (ret < 0)
434 {
435 if (errno == ENOSYS || errno == EOPNOTSUPP)
436 return chmod_or_fchmod (name, desc, mode);
437 return -1;
438 }
439
440 if (mode & (S_ISUID | S_ISGID | S_ISVTX))
441 {
442 /* We did not call chmod so far, so the special bits have not yet
443 been set. */
444 return chmod_or_fchmod (name, desc, mode);
445 }
446 return 0;
447
448 # elif HAVE_ACLX_GET && 0 /* AIX */
449
450 /* TODO: use aclx_fput or aclx_put, respectively */
451
452 # elif HAVE_STATACL /* older AIX */
453
454 union { struct acl a; char room[128]; } u;
455 int ret;
456
457 u.a.acl_len = (char *) &u.a.acl_ext[0] - (char *) &u.a; /* no entries */
458 u.a.acl_mode = mode & ~(S_IXACL | 0777);
459 u.a.u_access = (mode >> 6) & 7;
460 u.a.g_access = (mode >> 3) & 7;
461 u.a.o_access = mode & 7;
462
463 if (desc != -1)
464 ret = fchacl (desc, &u.a, u.a.acl_len);
465 else
466 ret = chacl (name, &u.a, u.a.acl_len);
467
468 if (ret < 0 && errno == ENOSYS)
469 return chmod_or_fchmod (name, desc, mode);
470
471 return ret;
472
473 # else /* Unknown flavor of ACLs */
474 return chmod_or_fchmod (name, desc, mode);
475 # endif
476 #else /* !USE_ACL */
477 return chmod_or_fchmod (name, desc, mode);
478 #endif
479 }
480
481 /* As with qset_acl, but also output a diagnostic on failure. */
482
483 int
set_acl(char const * name,int desc,mode_t mode)484 set_acl (char const *name, int desc, mode_t mode)
485 {
486 int r = qset_acl (name, desc, mode);
487 if (r != 0)
488 error (0, errno, _("setting permissions for %s"), quote (name));
489 return r;
490 }
491