lib/file-has-acl.c

   1 /* Test whether a file has a nontrivial access control list.
   2
   3    Copyright (C) 2002-2003, 2005-2013 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, Andreas Grünbacher, and Bruno Haible.  */
  19
  20 /* Without this pragma, gcc 4.7.0 20120126 may suggest that the
  21    file_has_acl function might be candidate for attribute 'const'  */
  22 #if (__GNUC__ == 4 && 6 <= __GNUC_MINOR__) || 4 < __GNUC__
  23 # pragma GCC diagnostic ignored "-Wsuggest-attribute=const"
  24 #endif
  25
  26 #include <config.h>
  27
  28 #include "acl.h"
  29
  30 #include "acl-internal.h"
  31
  32
  33 #if USE_ACL && HAVE_ACL_GET_FILE
  34
  35 # if HAVE_ACL_TYPE_EXTENDED /* Mac OS X */
  36
  37 /* ACL is an ACL, from a file, stored as type ACL_TYPE_EXTENDED.
  38    Return 1 if the given ACL is non-trivial.
  39    Return 0 if it is trivial.  */
  40 int
  41 acl_extended_nontrivial (acl_t acl)
  42 {
  43   /* acl is non-trivial if it is non-empty.  */
  44   return (acl_entries (acl) > 0);
  45 }
  46
  47 # else /* Linux, FreeBSD, IRIX, Tru64 */
  48
  49 /* ACL is an ACL, from a file, stored as type ACL_TYPE_ACCESS.
  50    Return 1 if the given ACL is non-trivial.
  51    Return 0 if it is trivial, i.e. equivalent to a simple stat() mode.
  52    Return -1 and set errno upon failure to determine it.  */
  53 int
  54 acl_access_nontrivial (acl_t acl)
  55 {
  56   /* acl is non-trivial if it has some entries other than for "user::",
  57      "group::", and "other::".  Normally these three should be present
  58      at least, allowing us to write
  59         return (3 < acl_entries (acl));
  60      but the following code is more robust.  */
  61 #  if HAVE_ACL_FIRST_ENTRY /* Linux, FreeBSD */
  62
  63   acl_entry_t ace;
  64   int got_one;
  65
  66   for (got_one = acl_get_entry (acl, ACL_FIRST_ENTRY, &ace);
  67        got_one > 0;
  68        got_one = acl_get_entry (acl, ACL_NEXT_ENTRY, &ace))
  69     {
  70       acl_tag_t tag;
  71       if (acl_get_tag_type (ace, &tag) < 0)
  72         return -1;
  73       if (!(tag == ACL_USER_OBJ || tag == ACL_GROUP_OBJ || tag == ACL_OTHER))
  74         return 1;
  75     }
  76   return got_one;
  77
  78 #  else /* IRIX, Tru64 */
  79 #   if HAVE_ACL_TO_SHORT_TEXT /* IRIX */
  80   /* Don't use acl_get_entry: it is undocumented.  */
  81
  82   int count = acl->acl_cnt;
  83   int i;
  84
  85   for (i = 0; i < count; i++)
  86     {
  87       acl_entry_t ace = &acl->acl_entry[i];
  88       acl_tag_t tag = ace->ae_tag;
  89
  90       if (!(tag == ACL_USER_OBJ || tag == ACL_GROUP_OBJ
  91             || tag == ACL_OTHER_OBJ))
  92         return 1;
  93     }
  94   return 0;
  95
  96 #   endif
  97 #   if HAVE_ACL_FREE_TEXT /* Tru64 */
  98   /* Don't use acl_get_entry: it takes only one argument and does not work.  */
  99
 100   int count = acl->acl_num;
 101   acl_entry_t ace;
 102
 103   for (ace = acl->acl_first; count > 0; ace = ace->next, count--)
 104     {
 105       acl_tag_t tag;
 106       acl_perm_t perm;
 107
 108       tag = ace->entry->acl_type;
 109       if (!(tag == ACL_USER_OBJ || tag == ACL_GROUP_OBJ || tag == ACL_OTHER))
 110         return 1;
 111
 112       perm = ace->entry->acl_perm;
 113       /* On Tru64, perm can also contain non-standard bits such as
 114          PERM_INSERT, PERM_DELETE, PERM_MODIFY, PERM_LOOKUP, ... */
 115       if ((perm & ~(ACL_READ | ACL_WRITE | ACL_EXECUTE)) != 0)
 116         return 1;
 117     }
 118   return 0;
 119
 120 #   endif
 121 #  endif
 122 }
 123
 124 # endif
 125
 126
 127 #elif USE_ACL && HAVE_FACL && defined GETACL /* Solaris, Cygwin, not HP-UX */
 128
 129 /* Test an ACL retrieved with GETACL.
 130    Return 1 if the given ACL, consisting of COUNT entries, is non-trivial.
 131    Return 0 if it is trivial, i.e. equivalent to a simple stat() mode.  */
 132 int
 133 acl_nontrivial (int count, aclent_t *entries)
 134 {
 135   int i;
 136
 137   for (i = 0; i < count; i++)
 138     {
 139       aclent_t *ace = &entries[i];
 140
 141       /* Note: If ace->a_type = USER_OBJ, ace->a_id is the st_uid from stat().
 142          If ace->a_type = GROUP_OBJ, ace->a_id is the st_gid from stat().
 143          We don't need to check ace->a_id in these cases.  */
 144       if (!(ace->a_type == USER_OBJ
 145             || ace->a_type == GROUP_OBJ
 146             || ace->a_type == OTHER_OBJ
 147             /* Note: Cygwin does not return a CLASS_OBJ ("mask:") entry
 148                sometimes.  */
 149             || ace->a_type == CLASS_OBJ))
 150         return 1;
 151     }
 152   return 0;
 153 }
 154
 155 # ifdef ACE_GETACL
 156
 157 /* A shortcut for a bitmask.  */
 158 #  define NEW_ACE_WRITEA_DATA (NEW_ACE_WRITE_DATA | NEW_ACE_APPEND_DATA)
 159
 160 /* Test an ACL retrieved with ACE_GETACL.
 161    Return 1 if the given ACL, consisting of COUNT entries, is non-trivial.
 162    Return 0 if it is trivial, i.e. equivalent to a simple stat() mode.  */
 163 int
 164 acl_ace_nontrivial (int count, ace_t *entries)
 165 {
 166   int i;
 167
 168   /* The flags in the ace_t structure changed in a binary incompatible way
 169      when ACL_NO_TRIVIAL etc. were introduced in <sys/acl.h> version 1.15.
 170      How to distinguish the two conventions at runtime?
 171      In the old convention, usually three ACEs have a_flags = ACE_OWNER /
 172      ACE_GROUP / ACE_OTHER, in the range 0x0100..0x0400.  In the new
 173      convention, these values are not used.  */
 174   int old_convention = 0;
 175
 176   for (i = 0; i < count; i++)
 177     if (entries[i].a_flags & (OLD_ACE_OWNER | OLD_ACE_GROUP | OLD_ACE_OTHER))
 178       {
 179         old_convention = 1;
 180         break;
 181       }
 182
 183   if (old_convention)
 184     /* Running on Solaris 10.  */
 185     for (i = 0; i < count; i++)
 186       {
 187         ace_t *ace = &entries[i];
 188
 189         /* Note:
 190            If ace->a_flags = ACE_OWNER, ace->a_who is the st_uid from stat().
 191            If ace->a_flags = ACE_GROUP, ace->a_who is the st_gid from stat().
 192            We don't need to check ace->a_who in these cases.  */
 193         if (!(ace->a_type == OLD_ALLOW
 194               && (ace->a_flags == OLD_ACE_OWNER
 195                   || ace->a_flags == OLD_ACE_GROUP
 196                   || ace->a_flags == OLD_ACE_OTHER)))
 197           return 1;
 198       }
 199   else
 200     {
 201       /* Running on Solaris 10 (newer version) or Solaris 11.  */
 202       unsigned int access_masks[6] =
 203         {
 204           0, /* owner@ deny */
 205           0, /* owner@ allow */
 206           0, /* group@ deny */
 207           0, /* group@ allow */
 208           0, /* everyone@ deny */
 209           0  /* everyone@ allow */
 210         };
 211
 212       for (i = 0; i < count; i++)
 213         {
 214           ace_t *ace = &entries[i];
 215           unsigned int index1;
 216           unsigned int index2;
 217
 218           if (ace->a_type == NEW_ACE_ACCESS_ALLOWED_ACE_TYPE)
 219             index1 = 1;
 220           else if (ace->a_type == NEW_ACE_ACCESS_DENIED_ACE_TYPE)
 221             index1 = 0;
 222           else
 223             return 1;
 224
 225           if (ace->a_flags == NEW_ACE_OWNER)
 226             index2 = 0;
 227           else if (ace->a_flags == (NEW_ACE_GROUP | NEW_ACE_IDENTIFIER_GROUP))
 228             index2 = 2;
 229           else if (ace->a_flags == NEW_ACE_EVERYONE)
 230             index2 = 4;
 231           else
 232             return 1;
 233
 234           access_masks[index1 + index2] |= ace->a_access_mask;
 235         }
 236
 237       /* The same bit shouldn't be both allowed and denied.  */
 238       if (access_masks[0] & access_masks[1])
 239         return 1;
 240       if (access_masks[2] & access_masks[3])
 241         return 1;
 242       if (access_masks[4] & access_masks[5])
 243         return 1;
 244
 245       /* Check minimum masks.  */
 246       if ((NEW_ACE_WRITE_NAMED_ATTRS
 247            | NEW_ACE_WRITE_ATTRIBUTES
 248            | NEW_ACE_WRITE_ACL
 249            | NEW_ACE_WRITE_OWNER)
 250           & ~ access_masks[1])
 251         return 1;
 252       access_masks[1] &= ~(NEW_ACE_WRITE_NAMED_ATTRS
 253                            | NEW_ACE_WRITE_ATTRIBUTES
 254                            | NEW_ACE_WRITE_ACL
 255                            | NEW_ACE_WRITE_OWNER);
 256       if ((NEW_ACE_READ_NAMED_ATTRS
 257            | NEW_ACE_READ_ATTRIBUTES
 258            | NEW_ACE_READ_ACL
 259            | NEW_ACE_SYNCHRONIZE)
 260           & ~ access_masks[5])
 261         return 1;
 262       access_masks[5] &= ~(NEW_ACE_READ_NAMED_ATTRS
 263                            | NEW_ACE_READ_ATTRIBUTES
 264                            | NEW_ACE_READ_ACL
 265                            | NEW_ACE_SYNCHRONIZE);
 266
 267       /* Check the allowed or denied bits.  */
 268       switch ((access_masks[0] | access_masks[1])
 269               & ~(NEW_ACE_READ_NAMED_ATTRS
 270                   | NEW_ACE_READ_ATTRIBUTES
 271                   | NEW_ACE_READ_ACL
 272                   | NEW_ACE_SYNCHRONIZE))
 273         {
 274         case 0:
 275         case NEW_ACE_READ_DATA:
 276         case                     NEW_ACE_WRITEA_DATA:
 277         case NEW_ACE_READ_DATA | NEW_ACE_WRITEA_DATA:
 278         case                                           NEW_ACE_EXECUTE:
 279         case NEW_ACE_READ_DATA |                       NEW_ACE_EXECUTE:
 280         case                     NEW_ACE_WRITEA_DATA | NEW_ACE_EXECUTE:
 281         case NEW_ACE_READ_DATA | NEW_ACE_WRITEA_DATA | NEW_ACE_EXECUTE:
 282           break;
 283         default:
 284           return 1;
 285         }
 286       switch ((access_masks[2] | access_masks[3])
 287               & ~(NEW_ACE_READ_NAMED_ATTRS
 288                   | NEW_ACE_READ_ATTRIBUTES
 289                   | NEW_ACE_READ_ACL
 290                   | NEW_ACE_SYNCHRONIZE))
 291         {
 292         case 0:
 293         case NEW_ACE_READ_DATA:
 294         case                     NEW_ACE_WRITEA_DATA:
 295         case NEW_ACE_READ_DATA | NEW_ACE_WRITEA_DATA:
 296         case                                           NEW_ACE_EXECUTE:
 297         case NEW_ACE_READ_DATA |                       NEW_ACE_EXECUTE:
 298         case                     NEW_ACE_WRITEA_DATA | NEW_ACE_EXECUTE:
 299         case NEW_ACE_READ_DATA | NEW_ACE_WRITEA_DATA | NEW_ACE_EXECUTE:
 300           break;
 301         default:
 302           return 1;
 303         }
 304       switch ((access_masks[4] | access_masks[5])
 305               & ~(NEW_ACE_WRITE_NAMED_ATTRS
 306                   | NEW_ACE_WRITE_ATTRIBUTES
 307                   | NEW_ACE_WRITE_ACL
 308                   | NEW_ACE_WRITE_OWNER))
 309         {
 310         case 0:
 311         case NEW_ACE_READ_DATA:
 312         case                     NEW_ACE_WRITEA_DATA:
 313         case NEW_ACE_READ_DATA | NEW_ACE_WRITEA_DATA:
 314         case                                           NEW_ACE_EXECUTE:
 315         case NEW_ACE_READ_DATA |                       NEW_ACE_EXECUTE:
 316         case                     NEW_ACE_WRITEA_DATA | NEW_ACE_EXECUTE:
 317         case NEW_ACE_READ_DATA | NEW_ACE_WRITEA_DATA | NEW_ACE_EXECUTE:
 318           break;
 319         default:
 320           return 1;
 321         }
 322
 323       /* Check that the NEW_ACE_WRITE_DATA and NEW_ACE_APPEND_DATA bits are
 324          either both allowed or both denied.  */
 325       if (((access_masks[0] & NEW_ACE_WRITE_DATA) != 0)
 326           != ((access_masks[0] & NEW_ACE_APPEND_DATA) != 0))
 327         return 1;
 328       if (((access_masks[2] & NEW_ACE_WRITE_DATA) != 0)
 329           != ((access_masks[2] & NEW_ACE_APPEND_DATA) != 0))
 330         return 1;
 331       if (((access_masks[4] & NEW_ACE_WRITE_DATA) != 0)
 332           != ((access_masks[4] & NEW_ACE_APPEND_DATA) != 0))
 333         return 1;
 334     }
 335
 336   return 0;
 337 }
 338
 339 # endif
 340
 341 #elif USE_ACL && HAVE_GETACL /* HP-UX */
 342
 343 /* Return 1 if the given ACL is non-trivial.
 344    Return 0 if it is trivial, i.e. equivalent to a simple stat() mode.  */
 345 int
 346 acl_nontrivial (int count, struct acl_entry *entries, struct stat *sb)
 347 {
 348   int i;
 349
 350   for (i = 0; i < count; i++)
 351     {
 352       struct acl_entry *ace = &entries[i];
 353
 354       if (!((ace->uid == sb->st_uid && ace->gid == ACL_NSGROUP)
 355             || (ace->uid == ACL_NSUSER && ace->gid == sb->st_gid)
 356             || (ace->uid == ACL_NSUSER && ace->gid == ACL_NSGROUP)))
 357         return 1;
 358     }
 359   return 0;
 360 }
 361
 362 # if HAVE_ACLV_H /* HP-UX >= 11.11 */
 363
 364 /* Return 1 if the given ACL is non-trivial.
 365    Return 0 if it is trivial, i.e. equivalent to a simple stat() mode.  */
 366 int
 367 aclv_nontrivial (int count, struct acl *entries)
 368 {
 369   int i;
 370
 371   for (i = 0; i < count; i++)
 372     {
 373       struct acl *ace = &entries[i];
 374
 375       /* Note: If ace->a_type = USER_OBJ, ace->a_id is the st_uid from stat().
 376          If ace->a_type = GROUP_OBJ, ace->a_id is the st_gid from stat().
 377          We don't need to check ace->a_id in these cases.  */
 378       if (!(ace->a_type == USER_OBJ /* no need to check ace->a_id here */
 379             || ace->a_type == GROUP_OBJ /* no need to check ace->a_id here */
 380             || ace->a_type == CLASS_OBJ
 381             || ace->a_type == OTHER_OBJ))
 382         return 1;
 383     }
 384   return 0;
 385 }
 386
 387 # endif
 388
 389 #elif USE_ACL && (HAVE_ACLX_GET || HAVE_STATACL) /* AIX */
 390
 391 /* Return 1 if the given ACL is non-trivial.
 392    Return 0 if it is trivial, i.e. equivalent to a simple stat() mode.  */
 393 int
 394 acl_nontrivial (struct acl *a)
 395 {
 396   /* The normal way to iterate through an ACL is like this:
 397        struct acl_entry *ace;
 398        for (ace = a->acl_ext; ace != acl_last (a); ace = acl_nxt (ace))
 399          {
 400            struct ace_id *aei;
 401            switch (ace->ace_type)
 402              {
 403              case ACC_PERMIT:
 404              case ACC_DENY:
 405              case ACC_SPECIFY:
 406                ...;
 407              }
 408            for (aei = ace->ace_id; aei != id_last (ace); aei = id_nxt (aei))
 409              ...
 410          }
 411    */
 412   return (acl_last (a) != a->acl_ext ? 1 : 0);
 413 }
 414
 415 # if HAVE_ACLX_GET && defined ACL_AIX_WIP /* newer AIX */
 416
 417 /* Return 1 if the given ACL is non-trivial.
 418    Return 0 if it is trivial, i.e. equivalent to a simple stat() mode.  */
 419 int
 420 acl_nfs4_nontrivial (nfs4_acl_int_t *a)
 421 {
 422 #  if 1 /* let's try this first */
 423   return (a->aclEntryN > 0 ? 1 : 0);
 424 #  else
 425   int count = a->aclEntryN;
 426   int i;
 427
 428   for (i = 0; i < count; i++)
 429     {
 430       nfs4_ace_int_t *ace = &a->aclEntry[i];
 431
 432       if (!((ace->flags & ACE4_ID_SPECIAL) != 0
 433             && (ace->aceWho.special_whoid == ACE4_WHO_OWNER
 434                 || ace->aceWho.special_whoid == ACE4_WHO_GROUP
 435                 || ace->aceWho.special_whoid == ACE4_WHO_EVERYONE)
 436             && ace->aceType == ACE4_ACCESS_ALLOWED_ACE_TYPE
 437             && ace->aceFlags == 0
 438             && (ace->aceMask & ~(ACE4_READ_DATA | ACE4_LIST_DIRECTORY
 439                                  | ACE4_WRITE_DATA | ACE4_ADD_FILE
 440                                  | ACE4_EXECUTE)) == 0))
 441         return 1;
 442     }
 443   return 0;
 444 #  endif
 445 }
 446
 447 # endif
 448
 449 #elif USE_ACL && HAVE_ACLSORT /* NonStop Kernel */
 450
 451 /* Test an ACL retrieved with ACL_GET.
 452    Return 1 if the given ACL, consisting of COUNT entries, is non-trivial.
 453    Return 0 if it is trivial, i.e. equivalent to a simple stat() mode.  */
 454 int
 455 acl_nontrivial (int count, struct acl *entries)
 456 {
 457   int i;
 458
 459   for (i = 0; i < count; i++)
 460     {
 461       struct acl *ace = &entries[i];
 462
 463       /* Note: If ace->a_type = USER_OBJ, ace->a_id is the st_uid from stat().
 464          If ace->a_type = GROUP_OBJ, ace->a_id is the st_gid from stat().
 465          We don't need to check ace->a_id in these cases.  */
 466       if (!(ace->a_type == USER_OBJ /* no need to check ace->a_id here */
 467             || ace->a_type == GROUP_OBJ /* no need to check ace->a_id here */
 468             || ace->a_type == CLASS_OBJ
 469             || ace->a_type == OTHER_OBJ))
 470         return 1;
 471     }
 472   return 0;
 473 }
 474
 475 #endif
 476
 477
 478 /* Return 1 if NAME has a nontrivial access control list, 0 if NAME
 479    only has no or a base access control list, and -1 (setting errno)
 480    on error.  SB must be set to the stat buffer of NAME, obtained
 481    through stat() or lstat().  */
 482
 483 int
 484 file_has_acl (char const *name, struct stat const *sb)
 485 {
 486 #if USE_ACL
 487   if (! S_ISLNK (sb->st_mode))
 488     {
 489 # if HAVE_ACL_GET_FILE
 490
 491       /* POSIX 1003.1e (draft 17 -- abandoned) specific version.  */
 492       /* Linux, FreeBSD, Mac OS X, IRIX, Tru64 */
 493       int ret;
 494
 495       if (HAVE_ACL_EXTENDED_FILE) /* Linux */
 496         {
 497           /* On Linux, acl_extended_file is an optimized function: It only
 498              makes two calls to getxattr(), one for ACL_TYPE_ACCESS, one for
 499              ACL_TYPE_DEFAULT.  */
 500           ret = acl_extended_file (name);
 501         }
 502       else /* FreeBSD, Mac OS X, IRIX, Tru64 */
 503         {
 504 #  if HAVE_ACL_TYPE_EXTENDED /* Mac OS X */
 505           /* On Mac OS X, acl_get_file (name, ACL_TYPE_ACCESS)
 506              and acl_get_file (name, ACL_TYPE_DEFAULT)
 507              always return NULL / EINVAL.  There is no point in making
 508              these two useless calls.  The real ACL is retrieved through
 509              acl_get_file (name, ACL_TYPE_EXTENDED).  */
 510           acl_t acl = acl_get_file (name, ACL_TYPE_EXTENDED);
 511           if (acl)
 512             {
 513               ret = acl_extended_nontrivial (acl);
 514               acl_free (acl);
 515             }
 516           else
 517             ret = -1;
 518 #  else /* FreeBSD, IRIX, Tru64 */
 519           acl_t acl = acl_get_file (name, ACL_TYPE_ACCESS);
 520           if (acl)
 521             {
 522               int saved_errno;
 523
 524               ret = acl_access_nontrivial (acl);
 525               saved_errno = errno;
 526               acl_free (acl);
 527               errno = saved_errno;
 528 #   if HAVE_ACL_FREE_TEXT /* Tru64 */
 529               /* On OSF/1, acl_get_file (name, ACL_TYPE_DEFAULT) always
 530                  returns NULL with errno not set.  There is no point in
 531                  making this call.  */
 532 #   else /* FreeBSD, IRIX */
 533               /* On Linux, FreeBSD, IRIX, acl_get_file (name, ACL_TYPE_ACCESS)
 534                  and acl_get_file (name, ACL_TYPE_DEFAULT) on a directory
 535                  either both succeed or both fail; it depends on the
 536                  file system.  Therefore there is no point in making the second
 537                  call if the first one already failed.  */
 538               if (ret == 0 && S_ISDIR (sb->st_mode))
 539                 {
 540                   acl = acl_get_file (name, ACL_TYPE_DEFAULT);
 541                   if (acl)
 542                     {
 543                       ret = (0 < acl_entries (acl));
 544                       acl_free (acl);
 545                     }
 546                   else
 547                     ret = -1;
 548                 }
 549 #   endif
 550             }
 551           else
 552             ret = -1;
 553 #  endif
 554         }
 555       if (ret < 0)
 556         return - acl_errno_valid (errno);
 557       return ret;
 558
 559 # elif HAVE_FACL && defined GETACL /* Solaris, Cygwin, not HP-UX */
 560
 561 #  if defined ACL_NO_TRIVIAL
 562
 563       /* Solaris 10 (newer version), which has additional API declared in
 564          <sys/acl.h> (acl_t) and implemented in libsec (acl_set, acl_trivial,
 565          acl_fromtext, ...).  */
 566       return acl_trivial (name);
 567
 568 #  else /* Solaris, Cygwin, general case */
 569
 570       /* Solaris 2.5 through Solaris 10, Cygwin, and contemporaneous versions
 571          of Unixware.  The acl() call returns the access and default ACL both
 572          at once.  */
 573       {
 574         /* Initially, try to read the entries into a stack-allocated buffer.
 575            Use malloc if it does not fit.  */
 576         enum
 577           {
 578             alloc_init = 4000 / sizeof (aclent_t), /* >= 3 */
 579             alloc_max = MIN (INT_MAX, SIZE_MAX / sizeof (aclent_t))
 580           };
 581         aclent_t buf[alloc_init];
 582         size_t alloc = alloc_init;
 583         aclent_t *entries = buf;
 584         aclent_t *malloced = NULL;
 585         int count;
 586
 587         for (;;)
 588           {
 589             count = acl (name, GETACL, alloc, entries);
 590             if (count < 0 && errno == ENOSPC)
 591               {
 592                 /* Increase the size of the buffer.  */
 593                 free (malloced);
 594                 if (alloc > alloc_max / 2)
 595                   {
 596                     errno = ENOMEM;
 597                     return -1;
 598                   }
 599                 alloc = 2 * alloc; /* <= alloc_max */
 600                 entries = malloced =
 601                   (aclent_t *) malloc (alloc * sizeof (aclent_t));
 602                 if (entries == NULL)
 603                   {
 604                     errno = ENOMEM;
 605                     return -1;
 606                   }
 607                 continue;
 608               }
 609             break;
 610           }
 611         if (count < 0)
 612           {
 613             if (errno == ENOSYS || errno == ENOTSUP)
 614               ;
 615             else
 616               {
 617                 int saved_errno = errno;
 618                 free (malloced);
 619                 errno = saved_errno;
 620                 return -1;
 621               }
 622           }
 623         else if (count == 0)
 624           ;
 625         else
 626           {
 627             /* Don't use MIN_ACL_ENTRIES:  It's set to 4 on Cygwin, but Cygwin
 628                returns only 3 entries for files with no ACL.  But this is safe:
 629                If there are more than 4 entries, there cannot be only the
 630                "user::", "group::", "other:", and "mask:" entries.  */
 631             if (count > 4)
 632               {
 633                 free (malloced);
 634                 return 1;
 635               }
 636
 637             if (acl_nontrivial (count, entries))
 638               {
 639                 free (malloced);
 640                 return 1;
 641               }
 642           }
 643         free (malloced);
 644       }
 645
 646 #   ifdef ACE_GETACL
 647       /* Solaris also has a different variant of ACLs, used in ZFS and NFSv4
 648          file systems (whereas the other ones are used in UFS file systems).  */
 649       {
 650         /* Initially, try to read the entries into a stack-allocated buffer.
 651            Use malloc if it does not fit.  */
 652         enum
 653           {
 654             alloc_init = 4000 / sizeof (ace_t), /* >= 3 */
 655             alloc_max = MIN (INT_MAX, SIZE_MAX / sizeof (ace_t))
 656           };
 657         ace_t buf[alloc_init];
 658         size_t alloc = alloc_init;
 659         ace_t *entries = buf;
 660         ace_t *malloced = NULL;
 661         int count;
 662
 663         for (;;)
 664           {
 665             count = acl (name, ACE_GETACL, alloc, entries);
 666             if (count < 0 && errno == ENOSPC)
 667               {
 668                 /* Increase the size of the buffer.  */
 669                 free (malloced);
 670                 if (alloc > alloc_max / 2)
 671                   {
 672                     errno = ENOMEM;
 673                     return -1;
 674                   }
 675                 alloc = 2 * alloc; /* <= alloc_max */
 676                 entries = malloced = (ace_t *) malloc (alloc * sizeof (ace_t));
 677                 if (entries == NULL)
 678                   {
 679                     errno = ENOMEM;
 680                     return -1;
 681                   }
 682                 continue;
 683               }
 684             break;
 685           }
 686         if (count < 0)
 687           {
 688             if (errno == ENOSYS || errno == EINVAL)
 689               ;
 690             else
 691               {
 692                 int saved_errno = errno;
 693                 free (malloced);
 694                 errno = saved_errno;
 695                 return -1;
 696               }
 697           }
 698         else if (count == 0)
 699           ;
 700         else
 701           {
 702             /* In the old (original Solaris 10) convention:
 703                If there are more than 3 entries, there cannot be only the
 704                ACE_OWNER, ACE_GROUP, ACE_OTHER entries.
 705                In the newer Solaris 10 and Solaris 11 convention:
 706                If there are more than 6 entries, there cannot be only the
 707                ACE_OWNER, ACE_GROUP, ACE_EVERYONE entries, each once with
 708                NEW_ACE_ACCESS_ALLOWED_ACE_TYPE and once with
 709                NEW_ACE_ACCESS_DENIED_ACE_TYPE.  */
 710             if (count > 6)
 711               {
 712                 free (malloced);
 713                 return 1;
 714               }
 715
 716             if (acl_ace_nontrivial (count, entries))
 717               {
 718                 free (malloced);
 719                 return 1;
 720               }
 721           }
 722         free (malloced);
 723       }
 724 #   endif
 725
 726       return 0;
 727 #  endif
 728
 729 # elif HAVE_GETACL /* HP-UX */
 730
 731       {
 732         struct acl_entry entries[NACLENTRIES];
 733         int count;
 734
 735         count = getacl (name, NACLENTRIES, entries);
 736
 737         if (count < 0)
 738           {
 739             /* ENOSYS is seen on newer HP-UX versions.
 740                EOPNOTSUPP is typically seen on NFS mounts.
 741                ENOTSUP was seen on Quantum StorNext file systems (cvfs).  */
 742             if (errno == ENOSYS || errno == EOPNOTSUPP || errno == ENOTSUP)
 743               ;
 744             else
 745               return -1;
 746           }
 747         else if (count == 0)
 748           return 0;
 749         else /* count > 0 */
 750           {
 751             if (count > NACLENTRIES)
 752               /* If NACLENTRIES cannot be trusted, use dynamic memory
 753                  allocation.  */
 754               abort ();
 755
 756             /* If there are more than 3 entries, there cannot be only the
 757                (uid,%), (%,gid), (%,%) entries.  */
 758             if (count > 3)
 759               return 1;
 760
 761             {
 762               struct stat statbuf;
 763
 764               if (stat (name, &statbuf) < 0)
 765                 return -1;
 766
 767               return acl_nontrivial (count, entries, &statbuf);
 768             }
 769           }
 770       }
 771
 772 #  if HAVE_ACLV_H /* HP-UX >= 11.11 */
 773
 774       {
 775         struct acl entries[NACLVENTRIES];
 776         int count;
 777
 778         count = acl ((char *) name, ACL_GET, NACLVENTRIES, entries);
 779
 780         if (count < 0)
 781           {
 782             /* EOPNOTSUPP is seen on NFS in HP-UX 11.11, 11.23.
 783                EINVAL is seen on NFS in HP-UX 11.31.  */
 784             if (errno == ENOSYS || errno == EOPNOTSUPP || errno == EINVAL)
 785               ;
 786             else
 787               return -1;
 788           }
 789         else if (count == 0)
 790           return 0;
 791         else /* count > 0 */
 792           {
 793             if (count > NACLVENTRIES)
 794               /* If NACLVENTRIES cannot be trusted, use dynamic memory
 795                  allocation.  */
 796               abort ();
 797
 798             /* If there are more than 4 entries, there cannot be only the
 799                four base ACL entries.  */
 800             if (count > 4)
 801               return 1;
 802
 803             return aclv_nontrivial (count, entries);
 804           }
 805       }
 806
 807 #  endif
 808
 809 # elif HAVE_ACLX_GET && defined ACL_AIX_WIP /* AIX */
 810
 811       acl_type_t type;
 812       char aclbuf[1024];
 813       void *acl = aclbuf;
 814       size_t aclsize = sizeof (aclbuf);
 815       mode_t mode;
 816
 817       for (;;)
 818         {
 819           /* The docs say that type being 0 is equivalent to ACL_ANY, but it
 820              is not true, in AIX 5.3.  */
 821           type.u64 = ACL_ANY;
 822           if (aclx_get (name, 0, &type, aclbuf, &aclsize, &mode) >= 0)
 823             break;
 824           if (errno == ENOSYS)
 825             return 0;
 826           if (errno != ENOSPC)
 827             {
 828               if (acl != aclbuf)
 829                 {
 830                   int saved_errno = errno;
 831                   free (acl);
 832                   errno = saved_errno;
 833                 }
 834               return -1;
 835             }
 836           aclsize = 2 * aclsize;
 837           if (acl != aclbuf)
 838             free (acl);
 839           acl = malloc (aclsize);
 840           if (acl == NULL)
 841             {
 842               errno = ENOMEM;
 843               return -1;
 844             }
 845         }
 846
 847       if (type.u64 == ACL_AIXC)
 848         {
 849           int result = acl_nontrivial ((struct acl *) acl);
 850           if (acl != aclbuf)
 851             free (acl);
 852           return result;
 853         }
 854       else if (type.u64 == ACL_NFS4)
 855         {
 856           int result = acl_nfs4_nontrivial ((nfs4_acl_int_t *) acl);
 857           if (acl != aclbuf)
 858             free (acl);
 859           return result;
 860         }
 861       else
 862         {
 863           /* A newer type of ACL has been introduced in the system.
 864              We should better support it.  */
 865           if (acl != aclbuf)
 866             free (acl);
 867           errno = EINVAL;
 868           return -1;
 869         }
 870
 871 # elif HAVE_STATACL /* older AIX */
 872
 873       union { struct acl a; char room[4096]; } u;
 874
 875       if (statacl (name, STX_NORMAL, &u.a, sizeof (u)) < 0)
 876         return -1;
 877
 878       return acl_nontrivial (&u.a);
 879
 880 # elif HAVE_ACLSORT /* NonStop Kernel */
 881
 882       {
 883         struct acl entries[NACLENTRIES];
 884         int count;
 885
 886         count = acl ((char *) name, ACL_GET, NACLENTRIES, entries);
 887
 888         if (count < 0)
 889           {
 890             if (errno == ENOSYS || errno == ENOTSUP)
 891               ;
 892             else
 893               return -1;
 894           }
 895         else if (count == 0)
 896           return 0;
 897         else /* count > 0 */
 898           {
 899             if (count > NACLENTRIES)
 900               /* If NACLENTRIES cannot be trusted, use dynamic memory
 901                  allocation.  */
 902               abort ();
 903
 904             /* If there are more than 4 entries, there cannot be only the
 905                four base ACL entries.  */
 906             if (count > 4)
 907               return 1;
 908
 909             return acl_nontrivial (count, entries);
 910           }
 911       }
 912
 913 # endif
 914     }
 915 #endif
 916
 917   return 0;
 918 }