1 /* Test whether a file has a nontrivial access control list.
3 Copyright (C) 2002-2003, 2005-2011 Free Software Foundation, Inc.
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.
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.
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/>.
18 Written by Paul Eggert, Andreas Grünbacher, and Bruno Haible. */
24 #include "acl-internal.h"
27 #if USE_ACL && HAVE_ACL_GET_FILE
29 # if HAVE_ACL_TYPE_EXTENDED /* MacOS X */
31 /* ACL is an ACL, from a file, stored as type ACL_TYPE_EXTENDED.
32 Return 1 if the given ACL is non-trivial.
33 Return 0 if it is trivial. */
35 acl_extended_nontrivial (acl_t acl)
37 /* acl is non-trivial if it is non-empty. */
38 return (acl_entries (acl) > 0);
41 # else /* Linux, FreeBSD, IRIX, Tru64 */
43 /* ACL is an ACL, from a file, stored as type ACL_TYPE_ACCESS.
44 Return 1 if the given ACL is non-trivial.
45 Return 0 if it is trivial, i.e. equivalent to a simple stat() mode.
46 Return -1 and set errno upon failure to determine it. */
48 acl_access_nontrivial (acl_t acl)
50 /* acl is non-trivial if it has some entries other than for "user::",
51 "group::", and "other::". Normally these three should be present
52 at least, allowing us to write
53 return (3 < acl_entries (acl));
54 but the following code is more robust. */
55 # if HAVE_ACL_FIRST_ENTRY /* Linux, FreeBSD */
60 for (got_one = acl_get_entry (acl, ACL_FIRST_ENTRY, &ace);
62 got_one = acl_get_entry (acl, ACL_NEXT_ENTRY, &ace))
65 if (acl_get_tag_type (ace, &tag) < 0)
67 if (!(tag == ACL_USER_OBJ || tag == ACL_GROUP_OBJ || tag == ACL_OTHER))
72 # else /* IRIX, Tru64 */
73 # if HAVE_ACL_TO_SHORT_TEXT /* IRIX */
74 /* Don't use acl_get_entry: it is undocumented. */
76 int count = acl->acl_cnt;
79 for (i = 0; i < count; i++)
81 acl_entry_t ace = &acl->acl_entry[i];
82 acl_tag_t tag = ace->ae_tag;
84 if (!(tag == ACL_USER_OBJ || tag == ACL_GROUP_OBJ
85 || tag == ACL_OTHER_OBJ))
91 # if HAVE_ACL_FREE_TEXT /* Tru64 */
92 /* Don't use acl_get_entry: it takes only one argument and does not work. */
94 int count = acl->acl_num;
97 for (ace = acl->acl_first; count > 0; ace = ace->next, count--)
102 tag = ace->entry->acl_type;
103 if (!(tag == ACL_USER_OBJ || tag == ACL_GROUP_OBJ || tag == ACL_OTHER))
106 perm = ace->entry->acl_perm;
107 /* On Tru64, perm can also contain non-standard bits such as
108 PERM_INSERT, PERM_DELETE, PERM_MODIFY, PERM_LOOKUP, ... */
109 if ((perm & ~(ACL_READ | ACL_WRITE | ACL_EXECUTE)) != 0)
121 #elif USE_ACL && HAVE_FACL && defined GETACL /* Solaris, Cygwin, not HP-UX */
123 # if !defined ACL_NO_TRIVIAL /* Solaris <= 10, Cygwin */
125 /* Test an ACL retrieved with GETACL.
126 Return 1 if the given ACL, consisting of COUNT entries, is non-trivial.
127 Return 0 if it is trivial, i.e. equivalent to a simple stat() mode. */
129 acl_nontrivial (int count, aclent_t *entries)
133 for (i = 0; i < count; i++)
135 aclent_t *ace = &entries[i];
137 /* Note: If ace->a_type = USER_OBJ, ace->a_id is the st_uid from stat().
138 If ace->a_type = GROUP_OBJ, ace->a_id is the st_gid from stat().
139 We don't need to check ace->a_id in these cases. */
140 if (!(ace->a_type == USER_OBJ
141 || ace->a_type == GROUP_OBJ
142 || ace->a_type == OTHER_OBJ
143 /* Note: Cygwin does not return a CLASS_OBJ ("mask:") entry
145 || ace->a_type == CLASS_OBJ))
153 /* Test an ACL retrieved with ACE_GETACL.
154 Return 1 if the given ACL, consisting of COUNT entries, is non-trivial.
155 Return 0 if it is trivial, i.e. equivalent to a simple stat() mode. */
157 acl_ace_nontrivial (int count, ace_t *entries)
161 /* The flags in the ace_t structure changed in a binary incompatible way
162 when ACL_NO_TRIVIAL etc. were introduced in <sys/acl.h> version 1.15.
163 How to distinguish the two conventions at runtime?
164 In the old convention, usually three ACEs have a_flags = ACE_OWNER /
165 ACE_GROUP / ACE_OTHER, in the range 0x0100..0x0400. In the new
166 convention, these values are not used. */
167 int old_convention = 0;
169 for (i = 0; i < count; i++)
170 if (entries[i].a_flags & (ACE_OWNER | ACE_GROUP | ACE_OTHER))
177 /* Running on Solaris 10. */
178 for (i = 0; i < count; i++)
180 ace_t *ace = &entries[i];
183 If ace->a_flags = ACE_OWNER, ace->a_who is the st_uid from stat().
184 If ace->a_flags = ACE_GROUP, ace->a_who is the st_gid from stat().
185 We don't need to check ace->a_who in these cases. */
186 if (!(ace->a_type == ALLOW
187 && (ace->a_flags == ACE_OWNER
188 || ace->a_flags == ACE_GROUP
189 || ace->a_flags == ACE_OTHER)))
193 /* Running on Solaris 10 (newer version) or Solaris 11. */
194 for (i = 0; i < count; i++)
196 ace_t *ace = &entries[i];
198 if (!(ace->a_type == ACE_ACCESS_ALLOWED_ACE_TYPE
199 && (ace->a_flags == NEW_ACE_OWNER
201 == (NEW_ACE_GROUP | NEW_ACE_IDENTIFIER_GROUP)
202 || ace->a_flags == ACE_EVERYONE)
203 && (ace->a_access_mask
204 & ~(NEW_ACE_READ_DATA | NEW_ACE_WRITE_DATA | NEW_ACE_EXECUTE))
216 #elif USE_ACL && HAVE_GETACL /* HP-UX */
218 /* Return 1 if the given ACL is non-trivial.
219 Return 0 if it is trivial, i.e. equivalent to a simple stat() mode. */
221 acl_nontrivial (int count, struct acl_entry *entries, struct stat *sb)
225 for (i = 0; i < count; i++)
227 struct acl_entry *ace = &entries[i];
229 if (!((ace->uid == sb->st_uid && ace->gid == ACL_NSGROUP)
230 || (ace->uid == ACL_NSUSER && ace->gid == sb->st_gid)
231 || (ace->uid == ACL_NSUSER && ace->gid == ACL_NSGROUP)))
237 # if HAVE_ACLV_H /* HP-UX >= 11.11 */
239 /* Return 1 if the given ACL is non-trivial.
240 Return 0 if it is trivial, i.e. equivalent to a simple stat() mode. */
242 aclv_nontrivial (int count, struct acl *entries)
246 for (i = 0; i < count; i++)
248 struct acl *ace = &entries[i];
250 /* Note: If ace->a_type = USER_OBJ, ace->a_id is the st_uid from stat().
251 If ace->a_type = GROUP_OBJ, ace->a_id is the st_gid from stat().
252 We don't need to check ace->a_id in these cases. */
253 if (!(ace->a_type == USER_OBJ /* no need to check ace->a_id here */
254 || ace->a_type == GROUP_OBJ /* no need to check ace->a_id here */
255 || ace->a_type == CLASS_OBJ
256 || ace->a_type == OTHER_OBJ))
264 #elif USE_ACL && (HAVE_ACLX_GET || HAVE_STATACL) /* AIX */
266 /* Return 1 if the given ACL is non-trivial.
267 Return 0 if it is trivial, i.e. equivalent to a simple stat() mode. */
269 acl_nontrivial (struct acl *a)
271 /* The normal way to iterate through an ACL is like this:
272 struct acl_entry *ace;
273 for (ace = a->acl_ext; ace != acl_last (a); ace = acl_nxt (ace))
276 switch (ace->ace_type)
283 for (aei = ace->ace_id; aei != id_last (ace); aei = id_nxt (aei))
287 return (acl_last (a) != a->acl_ext ? 1 : 0);
290 # if HAVE_ACLX_GET && defined ACL_AIX_WIP /* newer AIX */
292 /* Return 1 if the given ACL is non-trivial.
293 Return 0 if it is trivial, i.e. equivalent to a simple stat() mode. */
295 acl_nfs4_nontrivial (nfs4_acl_int_t *a)
297 # if 1 /* let's try this first */
298 return (a->aclEntryN > 0 ? 1 : 0);
300 int count = a->aclEntryN;
303 for (i = 0; i < count; i++)
305 nfs4_ace_int_t *ace = &a->aclEntry[i];
307 if (!((ace->flags & ACE4_ID_SPECIAL) != 0
308 && (ace->aceWho.special_whoid == ACE4_WHO_OWNER
309 || ace->aceWho.special_whoid == ACE4_WHO_GROUP
310 || ace->aceWho.special_whoid == ACE4_WHO_EVERYONE)
311 && ace->aceType == ACE4_ACCESS_ALLOWED_ACE_TYPE
312 && ace->aceFlags == 0
313 && (ace->aceMask & ~(ACE4_READ_DATA | ACE4_LIST_DIRECTORY
314 | ACE4_WRITE_DATA | ACE4_ADD_FILE
315 | ACE4_EXECUTE)) == 0))
324 #elif USE_ACL && HAVE_ACLSORT /* NonStop Kernel */
326 /* Test an ACL retrieved with ACL_GET.
327 Return 1 if the given ACL, consisting of COUNT entries, is non-trivial.
328 Return 0 if it is trivial, i.e. equivalent to a simple stat() mode. */
330 acl_nontrivial (int count, struct acl *entries)
334 for (i = 0; i < count; i++)
336 struct acl *ace = &entries[i];
338 /* Note: If ace->a_type = USER_OBJ, ace->a_id is the st_uid from stat().
339 If ace->a_type = GROUP_OBJ, ace->a_id is the st_gid from stat().
340 We don't need to check ace->a_id in these cases. */
341 if (!(ace->a_type == USER_OBJ /* no need to check ace->a_id here */
342 || ace->a_type == GROUP_OBJ /* no need to check ace->a_id here */
343 || ace->a_type == CLASS_OBJ
344 || ace->a_type == OTHER_OBJ))
353 /* Return 1 if NAME has a nontrivial access control list, 0 if NAME
354 only has no or a base access control list, and -1 (setting errno)
355 on error. SB must be set to the stat buffer of FILE. */
358 file_has_acl (char const *name, struct stat const *sb)
361 if (! S_ISLNK (sb->st_mode))
363 # if HAVE_ACL_GET_FILE
365 /* POSIX 1003.1e (draft 17 -- abandoned) specific version. */
366 /* Linux, FreeBSD, MacOS X, IRIX, Tru64 */
369 if (HAVE_ACL_EXTENDED_FILE) /* Linux */
371 /* On Linux, acl_extended_file is an optimized function: It only
372 makes two calls to getxattr(), one for ACL_TYPE_ACCESS, one for
374 ret = acl_extended_file (name);
376 else /* FreeBSD, MacOS X, IRIX, Tru64 */
378 # if HAVE_ACL_TYPE_EXTENDED /* MacOS X */
379 /* On MacOS X, acl_get_file (name, ACL_TYPE_ACCESS)
380 and acl_get_file (name, ACL_TYPE_DEFAULT)
381 always return NULL / EINVAL. There is no point in making
382 these two useless calls. The real ACL is retrieved through
383 acl_get_file (name, ACL_TYPE_EXTENDED). */
384 acl_t acl = acl_get_file (name, ACL_TYPE_EXTENDED);
387 ret = acl_extended_nontrivial (acl);
392 # else /* FreeBSD, IRIX, Tru64 */
393 acl_t acl = acl_get_file (name, ACL_TYPE_ACCESS);
398 ret = acl_access_nontrivial (acl);
402 # if HAVE_ACL_FREE_TEXT /* Tru64 */
403 /* On OSF/1, acl_get_file (name, ACL_TYPE_DEFAULT) always
404 returns NULL with errno not set. There is no point in
406 # else /* FreeBSD, IRIX */
407 /* On Linux, FreeBSD, IRIX, acl_get_file (name, ACL_TYPE_ACCESS)
408 and acl_get_file (name, ACL_TYPE_DEFAULT) on a directory
409 either both succeed or both fail; it depends on the
410 file system. Therefore there is no point in making the second
411 call if the first one already failed. */
412 if (ret == 0 && S_ISDIR (sb->st_mode))
414 acl = acl_get_file (name, ACL_TYPE_DEFAULT);
417 ret = (0 < acl_entries (acl));
430 return ACL_NOT_WELL_SUPPORTED (errno) ? 0 : -1;
433 # elif HAVE_FACL && defined GETACLCNT /* Solaris, Cygwin, not HP-UX */
435 # if defined ACL_NO_TRIVIAL
437 /* Solaris 10 (newer version), which has additional API declared in
438 <sys/acl.h> (acl_t) and implemented in libsec (acl_set, acl_trivial,
439 acl_fromtext, ...). */
440 return acl_trivial (name);
442 # else /* Solaris, Cygwin, general case */
444 /* Solaris 2.5 through Solaris 10, Cygwin, and contemporaneous versions
445 of Unixware. The acl() call returns the access and default ACL both
453 count = acl (name, GETACLCNT, 0, NULL);
457 if (errno == ENOSYS || errno == ENOTSUP)
466 /* Don't use MIN_ACL_ENTRIES: It's set to 4 on Cygwin, but Cygwin
467 returns only 3 entries for files with no ACL. But this is safe:
468 If there are more than 4 entries, there cannot be only the
469 "user::", "group::", "other:", and "mask:" entries. */
473 entries = (aclent_t *) malloc (count * sizeof (aclent_t));
479 if (acl (name, GETACL, count, entries) == count)
481 if (acl_nontrivial (count, entries))
489 /* Huh? The number of ACL entries changed since the last call.
496 /* Solaris also has a different variant of ACLs, used in ZFS and NFSv4
497 file systems (whereas the other ones are used in UFS file systems). */
503 count = acl (name, ACE_GETACLCNT, 0, NULL);
507 if (errno == ENOSYS || errno == EINVAL)
516 /* If there are more than 3 entries, there cannot be only the
517 ACE_OWNER, ACE_GROUP, ACE_OTHER entries. */
521 entries = (ace_t *) malloc (count * sizeof (ace_t));
527 if (acl (name, ACE_GETACL, count, entries) == count)
529 if (acl_ace_nontrivial (count, entries))
537 /* Huh? The number of ACL entries changed since the last call.
547 # elif HAVE_GETACL /* HP-UX */
552 struct acl_entry entries[NACLENTRIES];
554 count = getacl (name, 0, NULL);
558 /* ENOSYS is seen on newer HP-UX versions.
559 EOPNOTSUPP is typically seen on NFS mounts.
560 ENOTSUP was seen on Quantum StorNext file systems (cvfs). */
561 if (errno == ENOSYS || errno == EOPNOTSUPP || errno == ENOTSUP)
570 if (count > NACLENTRIES)
571 /* If NACLENTRIES cannot be trusted, use dynamic memory
575 /* If there are more than 3 entries, there cannot be only the
576 (uid,%), (%,gid), (%,%) entries. */
580 if (getacl (name, count, entries) == count)
584 if (stat (name, &statbuf) < 0)
587 return acl_nontrivial (count, entries, &statbuf);
589 /* Huh? The number of ACL entries changed since the last call.
593 # if HAVE_ACLV_H /* HP-UX >= 11.11 */
598 struct acl entries[NACLVENTRIES];
600 count = acl ((char *) name, ACL_CNT, NACLVENTRIES, entries);
604 /* EOPNOTSUPP is seen on NFS in HP-UX 11.11, 11.23.
605 EINVAL is seen on NFS in HP-UX 11.31. */
606 if (errno == ENOSYS || errno == EOPNOTSUPP || errno == EINVAL)
615 if (count > NACLVENTRIES)
616 /* If NACLVENTRIES cannot be trusted, use dynamic memory
620 /* If there are more than 4 entries, there cannot be only the
621 four base ACL entries. */
625 if (acl ((char *) name, ACL_GET, count, entries) == count)
626 return aclv_nontrivial (count, entries);
627 /* Huh? The number of ACL entries changed since the last call.
633 # elif HAVE_ACLX_GET && defined ACL_AIX_WIP /* AIX */
638 size_t aclsize = sizeof (aclbuf);
643 /* The docs say that type being 0 is equivalent to ACL_ANY, but it
644 is not true, in AIX 5.3. */
646 if (aclx_get (name, 0, &type, aclbuf, &aclsize, &mode) >= 0)
652 int saved_errno = errno;
658 aclsize = 2 * aclsize;
661 acl = malloc (aclsize);
669 if (type.u64 == ACL_AIXC)
671 int result = acl_nontrivial ((struct acl *) acl);
676 else if (type.u64 == ACL_NFS4)
678 int result = acl_nfs4_nontrivial ((nfs4_acl_int_t *) acl);
685 /* A newer type of ACL has been introduced in the system.
686 We should better support it. */
693 # elif HAVE_STATACL /* older AIX */
695 union { struct acl a; char room[4096]; } u;
697 if (statacl (name, STX_NORMAL, &u.a, sizeof (u)) < 0)
700 return acl_nontrivial (&u.a);
702 # elif HAVE_ACLSORT /* NonStop Kernel */
705 struct acl entries[NACLENTRIES];
709 count = acl ((char *) name, ACL_CNT, NACLENTRIES, NULL);
717 if (count > NACLENTRIES)
718 /* If NACLENTRIES cannot be trusted, use dynamic memory
722 /* If there are more than 4 entries, there cannot be only the
723 four base ACL entries. */
727 if (acl ((char *) name, ACL_GET, count, entries) == count)
728 return acl_nontrivial (count, entries);
729 /* Huh? The number of ACL entries changed since the last call.