sys/kern/subr_acl_nfs4.c

   1 /*-
   2  * Copyright (c) 2008-2009 Edward Tomasz Napierała <trasz@FreeBSD.org>
   3  * All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer.
  10  * 2. Redistributions in binary form must reproduce the above copyright
  11  *    notice, this list of conditions and the following disclaimer in the
  12  *    documentation and/or other materials provided with the distribution.
  13  *
  14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
  15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
  18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  24  * SUCH DAMAGE.
  25  */
  26
  27 /*
  28  * ACL support routines specific to NFSv4 access control lists.  These are
  29  * utility routines for code common across file systems implementing NFSv4
  30  * ACLs.
  31  */
  32
  33 #ifdef _KERNEL
  34 #include <sys/cdefs.h>
  35 __FBSDID("$FreeBSD$");
  36
  37 #include <sys/param.h>
  38 #include <sys/systm.h>
  39 #include <sys/mount.h>
  40 #include <sys/priv.h>
  41 #include <sys/vnode.h>
  42 #include <sys/errno.h>
  43 #include <sys/stat.h>
  44 #include <sys/acl.h>
  45 #else
  46 #include <errno.h>
  47 #include <assert.h>
  48 #include <sys/acl.h>
  49 #include <sys/stat.h>
  50 #define KASSERT(a, b) assert(a)
  51 #define CTASSERT(a)
  52 #endif /* _KERNEL */
  53
  54 #ifdef _KERNEL
  55
  56 static struct {
  57         accmode_t accmode;
  58         int mask;
  59 } accmode2mask[] = {{VREAD, ACL_READ_DATA},
  60                     {VWRITE, ACL_WRITE_DATA},
  61                     {VAPPEND, ACL_APPEND_DATA},
  62                     {VEXEC, ACL_EXECUTE},
  63                     {VREAD_NAMED_ATTRS, ACL_READ_NAMED_ATTRS},
  64                     {VWRITE_NAMED_ATTRS, ACL_WRITE_NAMED_ATTRS},
  65                     {VDELETE_CHILD, ACL_DELETE_CHILD},
  66                     {VREAD_ATTRIBUTES, ACL_READ_ATTRIBUTES},
  67                     {VWRITE_ATTRIBUTES, ACL_WRITE_ATTRIBUTES},
  68                     {VDELETE, ACL_DELETE},
  69                     {VREAD_ACL, ACL_READ_ACL},
  70                     {VWRITE_ACL, ACL_WRITE_ACL},
  71                     {VWRITE_OWNER, ACL_WRITE_OWNER},
  72                     {VSYNCHRONIZE, ACL_SYNCHRONIZE},
  73                     {0, 0}};
  74
  75 static int
  76 _access_mask_from_accmode(accmode_t accmode)
  77 {
  78         int access_mask = 0, i;
  79
  80         for (i = 0; accmode2mask[i].accmode != 0; i++) {
  81                 if (accmode & accmode2mask[i].accmode)
  82                         access_mask |= accmode2mask[i].mask;
  83         }
  84
  85         /*
  86          * VAPPEND is just a modifier for VWRITE; if the caller asked
  87          * for 'VAPPEND | VWRITE', we want to check for ACL_APPEND_DATA only.
  88          */
  89         if (access_mask & ACL_APPEND_DATA)
  90                 access_mask &= ~ACL_WRITE_DATA;
  91
  92         return (access_mask);
  93 }
  94
  95 /*
  96  * Return 0, iff access is allowed, 1 otherwise.
  97  */
  98 static int
  99 _acl_denies(const struct acl *aclp, int access_mask, struct ucred *cred,
 100     int file_uid, int file_gid, int *denied_explicitly)
 101 {
 102         int i;
 103         const struct acl_entry *entry;
 104
 105         if (denied_explicitly != NULL)
 106                 *denied_explicitly = 0;
 107
 108         KASSERT(aclp->acl_cnt <= ACL_MAX_ENTRIES,
 109             ("aclp->acl_cnt <= ACL_MAX_ENTRIES"));
 110
 111         for (i = 0; i < aclp->acl_cnt; i++) {
 112                 entry = &(aclp->acl_entry[i]);
 113
 114                 if (entry->ae_entry_type != ACL_ENTRY_TYPE_ALLOW &&
 115                     entry->ae_entry_type != ACL_ENTRY_TYPE_DENY)
 116                         continue;
 117                 if (entry->ae_flags & ACL_ENTRY_INHERIT_ONLY)
 118                         continue;
 119                 switch (entry->ae_tag) {
 120                 case ACL_USER_OBJ:
 121                         if (file_uid != cred->cr_uid)
 122                                 continue;
 123                         break;
 124                 case ACL_USER:
 125                         if (entry->ae_id != cred->cr_uid)
 126                                 continue;
 127                         break;
 128                 case ACL_GROUP_OBJ:
 129                         if (!groupmember(file_gid, cred))
 130                                 continue;
 131                         break;
 132                 case ACL_GROUP:
 133                         if (!groupmember(entry->ae_id, cred))
 134                                 continue;
 135                         break;
 136                 default:
 137                         KASSERT(entry->ae_tag == ACL_EVERYONE,
 138                             ("entry->ae_tag == ACL_EVERYONE"));
 139                 }
 140
 141                 if (entry->ae_entry_type == ACL_ENTRY_TYPE_DENY) {
 142                         if (entry->ae_perm & access_mask) {
 143                                 if (denied_explicitly != NULL)
 144                                         *denied_explicitly = 1;
 145                                 return (1);
 146                         }
 147                 }
 148
 149                 access_mask &= ~(entry->ae_perm);
 150                 if (access_mask == 0)
 151                         return (0);
 152         }
 153
 154         return (1);
 155 }
 156
 157 int
 158 vaccess_acl_nfs4(enum vtype type, uid_t file_uid, gid_t file_gid,
 159     struct acl *aclp, accmode_t accmode, struct ucred *cred, int *privused)
 160 {
 161         accmode_t priv_granted = 0;
 162         int denied, explicitly_denied, access_mask, is_directory,
 163             must_be_owner = 0;
 164
 165         if (privused != NULL)
 166                 *privused = 0;
 167
 168         if (accmode & VADMIN)
 169                 must_be_owner = 1;
 170
 171         /*
 172          * Ignore VSYNCHRONIZE permission.
 173          */
 174         accmode &= ~VSYNCHRONIZE;
 175
 176         access_mask = _access_mask_from_accmode(accmode);
 177
 178         if (type == VDIR)
 179                 is_directory = 1;
 180         else
 181                 is_directory = 0;
 182
 183         /*
 184          * File owner is always allowed to read and write the ACL
 185          * and basic attributes.  This is to prevent a situation
 186          * where user would change ACL in a way that prevents him
 187          * from undoing the change.
 188          */
 189         if (file_uid == cred->cr_uid)
 190                 access_mask &= ~(ACL_READ_ACL | ACL_WRITE_ACL |
 191                     ACL_READ_ATTRIBUTES | ACL_WRITE_ATTRIBUTES);
 192
 193         /*
 194          * Ignore append permission for regular files; use write
 195          * permission instead.
 196          */
 197         if (!is_directory && (access_mask & ACL_APPEND_DATA)) {
 198                 access_mask &= ~ACL_APPEND_DATA;
 199                 access_mask |= ACL_WRITE_DATA;
 200         }
 201
 202         denied = _acl_denies(aclp, access_mask, cred, file_uid, file_gid,
 203             &explicitly_denied);
 204
 205         if (must_be_owner) {
 206                 if (file_uid != cred->cr_uid)
 207                         denied = EPERM;
 208         }
 209
 210         if (!denied)
 211                 return (0);
 212
 213         /*
 214          * Access failed.  Iff it was not denied explicitly and
 215          * VEXPLICIT_DENY flag was specified, allow access.
 216          */
 217         if ((accmode & VEXPLICIT_DENY) && explicitly_denied == 0)
 218                 return (0);
 219
 220         accmode &= ~VEXPLICIT_DENY;
 221
 222         /*
 223          * No match.  Try to use privileges, if there are any.
 224          */
 225         if (is_directory) {
 226                 if ((accmode & VEXEC) && !priv_check_cred(cred,
 227                     PRIV_VFS_LOOKUP, 0))
 228                         priv_granted |= VEXEC;
 229         } else {
 230                 if ((accmode & VEXEC) && !priv_check_cred(cred,
 231                     PRIV_VFS_EXEC, 0))
 232                         priv_granted |= VEXEC;
 233         }
 234
 235         if ((accmode & VREAD) && !priv_check_cred(cred, PRIV_VFS_READ, 0))
 236                 priv_granted |= VREAD;
 237
 238         if ((accmode & (VWRITE | VAPPEND | VDELETE_CHILD)) &&
 239             !priv_check_cred(cred, PRIV_VFS_WRITE, 0))
 240                 priv_granted |= (VWRITE | VAPPEND | VDELETE_CHILD);
 241
 242         if ((accmode & VADMIN_PERMS) &&
 243             !priv_check_cred(cred, PRIV_VFS_ADMIN, 0))
 244                 priv_granted |= VADMIN_PERMS;
 245
 246         if ((accmode & VSTAT_PERMS) &&
 247             !priv_check_cred(cred, PRIV_VFS_STAT, 0))
 248                 priv_granted |= VSTAT_PERMS;
 249
 250         if ((accmode & priv_granted) == accmode) {
 251                 if (privused != NULL)
 252                         *privused = 1;
 253
 254                 return (0);
 255         }
 256
 257         if (accmode & (VADMIN_PERMS | VDELETE_CHILD | VDELETE))
 258                 denied = EPERM;
 259         else
 260                 denied = EACCES;
 261
 262         return (denied);
 263 }
 264 #endif /* _KERNEL */
 265
 266 static int
 267 _acl_entry_matches(struct acl_entry *entry, acl_tag_t tag, acl_perm_t perm,
 268     acl_entry_type_t entry_type)
 269 {
 270         if (entry->ae_tag != tag)
 271                 return (0);
 272
 273         if (entry->ae_id != ACL_UNDEFINED_ID)
 274                 return (0);
 275
 276         if (entry->ae_perm != perm)
 277                 return (0);
 278
 279         if (entry->ae_entry_type != entry_type)
 280                 return (0);
 281
 282         if (entry->ae_flags != 0)
 283                 return (0);
 284
 285         return (1);
 286 }
 287
 288 static struct acl_entry *
 289 _acl_append(struct acl *aclp, acl_tag_t tag, acl_perm_t perm,
 290     acl_entry_type_t entry_type)
 291 {
 292         struct acl_entry *entry;
 293
 294         KASSERT(aclp->acl_cnt + 1 <= ACL_MAX_ENTRIES,
 295             ("aclp->acl_cnt + 1 <= ACL_MAX_ENTRIES"));
 296
 297         entry = &(aclp->acl_entry[aclp->acl_cnt]);
 298         aclp->acl_cnt++;
 299
 300         entry->ae_tag = tag;
 301         entry->ae_id = ACL_UNDEFINED_ID;
 302         entry->ae_perm = perm;
 303         entry->ae_entry_type = entry_type;
 304         entry->ae_flags = 0;
 305
 306         return (entry);
 307 }
 308
 309 static struct acl_entry *
 310 _acl_duplicate_entry(struct acl *aclp, int entry_index)
 311 {
 312         int i;
 313
 314         KASSERT(aclp->acl_cnt + 1 <= ACL_MAX_ENTRIES,
 315             ("aclp->acl_cnt + 1 <= ACL_MAX_ENTRIES"));
 316
 317         for (i = aclp->acl_cnt; i > entry_index; i--)
 318                 aclp->acl_entry[i] = aclp->acl_entry[i - 1];
 319
 320         aclp->acl_cnt++;
 321
 322         return (&(aclp->acl_entry[entry_index + 1]));
 323 }
 324
 325 /*
 326  * Calculate trivial ACL in a manner compatible with PSARC/2010/029.
 327  * Note that this results in an ACL different from (but semantically
 328  * equal to) the "canonical six" trivial ACL computed using algorithm
 329  * described in draft-ietf-nfsv4-minorversion1-03.txt, 3.16.6.2.
 330  */
 331 void
 332 acl_nfs4_trivial_from_mode(struct acl *aclp, mode_t mode)
 333 {
 334         acl_perm_t user_allow_first = 0, user_deny = 0, group_deny = 0;
 335         acl_perm_t user_allow, group_allow, everyone_allow;
 336
 337         KASSERT(aclp->acl_cnt == 0, ("aclp->acl_cnt == 0"));
 338
 339         user_allow = group_allow = everyone_allow = ACL_READ_ACL |
 340             ACL_READ_ATTRIBUTES | ACL_READ_NAMED_ATTRS | ACL_SYNCHRONIZE;
 341         user_allow |= ACL_WRITE_ACL | ACL_WRITE_OWNER | ACL_WRITE_ATTRIBUTES |
 342             ACL_WRITE_NAMED_ATTRS;
 343
 344         if (mode & S_IRUSR)
 345                 user_allow |= ACL_READ_DATA;
 346         if (mode & S_IWUSR)
 347                 user_allow |= (ACL_WRITE_DATA | ACL_APPEND_DATA);
 348         if (mode & S_IXUSR)
 349                 user_allow |= ACL_EXECUTE;
 350
 351         if (mode & S_IRGRP)
 352                 group_allow |= ACL_READ_DATA;
 353         if (mode & S_IWGRP)
 354                 group_allow |= (ACL_WRITE_DATA | ACL_APPEND_DATA);
 355         if (mode & S_IXGRP)
 356                 group_allow |= ACL_EXECUTE;
 357
 358         if (mode & S_IROTH)
 359                 everyone_allow |= ACL_READ_DATA;
 360         if (mode & S_IWOTH)
 361                 everyone_allow |= (ACL_WRITE_DATA | ACL_APPEND_DATA);
 362         if (mode & S_IXOTH)
 363                 everyone_allow |= ACL_EXECUTE;
 364
 365         user_deny = ((group_allow | everyone_allow) & ~user_allow);
 366         group_deny = everyone_allow & ~group_allow;
 367         user_allow_first = group_deny & ~user_deny;
 368
 369         if (user_allow_first != 0)
 370                 _acl_append(aclp, ACL_USER_OBJ, user_allow_first, ACL_ENTRY_TYPE_ALLOW);
 371         if (user_deny != 0)
 372                 _acl_append(aclp, ACL_USER_OBJ, user_deny, ACL_ENTRY_TYPE_DENY);
 373         if (group_deny != 0)
 374                 _acl_append(aclp, ACL_GROUP_OBJ, group_deny, ACL_ENTRY_TYPE_DENY);
 375         _acl_append(aclp, ACL_USER_OBJ, user_allow, ACL_ENTRY_TYPE_ALLOW);
 376         _acl_append(aclp, ACL_GROUP_OBJ, group_allow, ACL_ENTRY_TYPE_ALLOW);
 377         _acl_append(aclp, ACL_EVERYONE, everyone_allow, ACL_ENTRY_TYPE_ALLOW);
 378 }
 379
 380 void
 381 acl_nfs4_sync_acl_from_mode(struct acl *aclp, mode_t mode, int file_owner_id)
 382 {
 383         int i, meets, must_append;
 384         struct acl_entry *entry, *copy, *previous,
 385             *a1, *a2, *a3, *a4, *a5, *a6;
 386         mode_t amode;
 387         const int READ = 04;
 388         const int WRITE = 02;
 389         const int EXEC = 01;
 390
 391         KASSERT(aclp->acl_cnt >= 0, ("aclp->acl_cnt >= 0"));
 392         KASSERT(aclp->acl_cnt <= ACL_MAX_ENTRIES,
 393             ("aclp->acl_cnt <= ACL_MAX_ENTRIES"));
 394
 395         /*
 396          * NFSv4 Minor Version 1, draft-ietf-nfsv4-minorversion1-03.txt
 397          *
 398          * 3.16.6.3. Applying a Mode to an Existing ACL
 399          */
 400
 401         /*
 402          * 1. For each ACE:
 403          */
 404         for (i = 0; i < aclp->acl_cnt; i++) {
 405                 entry = &(aclp->acl_entry[i]);
 406
 407                 /*
 408                  * 1.1. If the type is neither ALLOW or DENY - skip.
 409                  */
 410                 if (entry->ae_entry_type != ACL_ENTRY_TYPE_ALLOW &&
 411                     entry->ae_entry_type != ACL_ENTRY_TYPE_DENY)
 412                         continue;
 413
 414                 /*
 415                  * 1.2. If ACL_ENTRY_INHERIT_ONLY is set - skip.
 416                  */
 417                 if (entry->ae_flags & ACL_ENTRY_INHERIT_ONLY)
 418                         continue;
 419
 420                 /*
 421                  * 1.3. If ACL_ENTRY_FILE_INHERIT or ACL_ENTRY_DIRECTORY_INHERIT
 422                  *      are set:
 423                  */
 424                 if (entry->ae_flags &
 425                     (ACL_ENTRY_FILE_INHERIT | ACL_ENTRY_DIRECTORY_INHERIT)) {
 426                         /*
 427                          * 1.3.1. A copy of the current ACE is made, and placed
 428                          *        in the ACL immediately following the current
 429                          *        ACE.
 430                          */
 431                         copy = _acl_duplicate_entry(aclp, i);
 432
 433                         /*
 434                          * 1.3.2. In the first ACE, the flag
 435                          *        ACL_ENTRY_INHERIT_ONLY is set.
 436                          */
 437                         entry->ae_flags |= ACL_ENTRY_INHERIT_ONLY;
 438
 439                         /*
 440                          * 1.3.3. In the second ACE, the following flags
 441                          *        are cleared:
 442                          *        ACL_ENTRY_FILE_INHERIT,
 443                          *        ACL_ENTRY_DIRECTORY_INHERIT,
 444                          *        ACL_ENTRY_NO_PROPAGATE_INHERIT.
 445                          */
 446                         copy->ae_flags &= ~(ACL_ENTRY_FILE_INHERIT |
 447                             ACL_ENTRY_DIRECTORY_INHERIT |
 448                             ACL_ENTRY_NO_PROPAGATE_INHERIT);
 449
 450                         /*
 451                          * The algorithm continues on with the second ACE.
 452                          */
 453                         i++;
 454                         entry = copy;
 455                 }
 456
 457                 /*
 458                  * 1.4. If it's owner@, group@ or everyone@ entry, clear
 459                  *      ACL_READ_DATA, ACL_WRITE_DATA, ACL_APPEND_DATA
 460                  *      and ACL_EXECUTE.  Continue to the next entry.
 461                  */
 462                 if (entry->ae_tag == ACL_USER_OBJ ||
 463                     entry->ae_tag == ACL_GROUP_OBJ ||
 464                     entry->ae_tag == ACL_EVERYONE) {
 465                         entry->ae_perm &= ~(ACL_READ_DATA | ACL_WRITE_DATA |
 466                             ACL_APPEND_DATA | ACL_EXECUTE);
 467                         continue;
 468                 }
 469
 470                 /*
 471                  * 1.5. Otherwise, if the "who" field did not match one
 472                  *      of OWNER@, GROUP@, EVERYONE@:
 473                  *
 474                  * 1.5.1. If the type is ALLOW, check the preceding ACE.
 475                  *        If it does not meet all of the following criteria:
 476                  */
 477                 if (entry->ae_entry_type != ACL_ENTRY_TYPE_ALLOW)
 478                         continue;
 479
 480                 meets = 0;
 481                 if (i > 0) {
 482                         meets = 1;
 483                         previous = &(aclp->acl_entry[i - 1]);
 484
 485                         /*
 486                          * 1.5.1.1. The type field is DENY,
 487                          */
 488                         if (previous->ae_entry_type != ACL_ENTRY_TYPE_DENY)
 489                                 meets = 0;
 490
 491                         /*
 492                          * 1.5.1.2. The "who" field is the same as the current
 493                          *          ACE,
 494                          *
 495                          * 1.5.1.3. The flag bit ACE4_IDENTIFIER_GROUP
 496                          *          is the same as it is in the current ACE,
 497                          *          and no other flag bits are set,
 498                          */
 499                         if (previous->ae_id != entry->ae_id ||
 500                             previous->ae_tag != entry->ae_tag)
 501                                 meets = 0;
 502
 503                         if (previous->ae_flags)
 504                                 meets = 0;
 505
 506                         /*
 507                          * 1.5.1.4. The mask bits are a subset of the mask bits
 508                          *          of the current ACE, and are also subset of
 509                          *          the following: ACL_READ_DATA,
 510                          *          ACL_WRITE_DATA, ACL_APPEND_DATA, ACL_EXECUTE
 511                          */
 512                         if (previous->ae_perm & ~(entry->ae_perm))
 513                                 meets = 0;
 514
 515                         if (previous->ae_perm & ~(ACL_READ_DATA |
 516                             ACL_WRITE_DATA | ACL_APPEND_DATA | ACL_EXECUTE))
 517                                 meets = 0;
 518                 }
 519
 520                 if (!meets) {
 521                         /*
 522                          * Then the ACE of type DENY, with a who equal
 523                          * to the current ACE, flag bits equal to
 524                          * (<current ACE flags> & <ACE_IDENTIFIER_GROUP>)
 525                          * and no mask bits, is prepended.
 526                          */
 527                         previous = entry;
 528                         entry = _acl_duplicate_entry(aclp, i);
 529
 530                         /* Adjust counter, as we've just added an entry. */
 531                         i++;
 532
 533                         previous->ae_tag = entry->ae_tag;
 534                         previous->ae_id = entry->ae_id;
 535                         previous->ae_flags = entry->ae_flags;
 536                         previous->ae_perm = 0;
 537                         previous->ae_entry_type = ACL_ENTRY_TYPE_DENY;
 538                 }
 539
 540                 /*
 541                  * 1.5.2. The following modifications are made to the prepended
 542                  *        ACE.  The intent is to mask the following ACE
 543                  *        to disallow ACL_READ_DATA, ACL_WRITE_DATA,
 544                  *        ACL_APPEND_DATA, or ACL_EXECUTE, based upon the group
 545                  *        permissions of the new mode.  As a special case,
 546                  *        if the ACE matches the current owner of the file,
 547                  *        the owner bits are used, rather than the group bits.
 548                  *        This is reflected in the algorithm below.
 549                  */
 550                 amode = mode >> 3;
 551
 552                 /*
 553                  * If ACE4_IDENTIFIER_GROUP is not set, and the "who" field
 554                  * in ACE matches the owner of the file, we shift amode three
 555                  * more bits, in order to have the owner permission bits
 556                  * placed in the three low order bits of amode.
 557                  */
 558                 if (entry->ae_tag == ACL_USER && entry->ae_id == file_owner_id)
 559                         amode = amode >> 3;
 560
 561                 if (entry->ae_perm & ACL_READ_DATA) {
 562                         if (amode & READ)
 563                                 previous->ae_perm &= ~ACL_READ_DATA;
 564                         else
 565                                 previous->ae_perm |= ACL_READ_DATA;
 566                 }
 567
 568                 if (entry->ae_perm & ACL_WRITE_DATA) {
 569                         if (amode & WRITE)
 570                                 previous->ae_perm &= ~ACL_WRITE_DATA;
 571                         else
 572                                 previous->ae_perm |= ACL_WRITE_DATA;
 573                 }
 574
 575                 if (entry->ae_perm & ACL_APPEND_DATA) {
 576                         if (amode & WRITE)
 577                                 previous->ae_perm &= ~ACL_APPEND_DATA;
 578                         else
 579                                 previous->ae_perm |= ACL_APPEND_DATA;
 580                 }
 581
 582                 if (entry->ae_perm & ACL_EXECUTE) {
 583                         if (amode & EXEC)
 584                                 previous->ae_perm &= ~ACL_EXECUTE;
 585                         else
 586                                 previous->ae_perm |= ACL_EXECUTE;
 587                 }
 588
 589                 /*
 590                  * 1.5.3. If ACE4_IDENTIFIER_GROUP is set in the flags
 591                  *        of the ALLOW ace:
 592                  *
 593                  * XXX: This point is not there in the Falkner's draft.
 594                  */
 595                 if (entry->ae_tag == ACL_GROUP &&
 596                     entry->ae_entry_type == ACL_ENTRY_TYPE_ALLOW) {
 597                         mode_t extramode, ownermode;
 598                         extramode = (mode >> 3) & 07;
 599                         ownermode = mode >> 6;
 600                         extramode &= ~ownermode;
 601
 602                         if (extramode) {
 603                                 if (extramode & READ) {
 604                                         entry->ae_perm &= ~ACL_READ_DATA;
 605                                         previous->ae_perm &= ~ACL_READ_DATA;
 606                                 }
 607
 608                                 if (extramode & WRITE) {
 609                                         entry->ae_perm &=
 610                                             ~(ACL_WRITE_DATA | ACL_APPEND_DATA);
 611                                         previous->ae_perm &=
 612                                             ~(ACL_WRITE_DATA | ACL_APPEND_DATA);
 613                                 }
 614
 615                                 if (extramode & EXEC) {
 616                                         entry->ae_perm &= ~ACL_EXECUTE;
 617                                         previous->ae_perm &= ~ACL_EXECUTE;
 618                                 }
 619                         }
 620                 }
 621         }
 622
 623         /*
 624          * 2. If there at least six ACEs, the final six ACEs are examined.
 625          *    If they are not equal to what we want, append six ACEs.
 626          */
 627         must_append = 0;
 628         if (aclp->acl_cnt < 6) {
 629                 must_append = 1;
 630         } else {
 631                 a6 = &(aclp->acl_entry[aclp->acl_cnt - 1]);
 632                 a5 = &(aclp->acl_entry[aclp->acl_cnt - 2]);
 633                 a4 = &(aclp->acl_entry[aclp->acl_cnt - 3]);
 634                 a3 = &(aclp->acl_entry[aclp->acl_cnt - 4]);
 635                 a2 = &(aclp->acl_entry[aclp->acl_cnt - 5]);
 636                 a1 = &(aclp->acl_entry[aclp->acl_cnt - 6]);
 637
 638                 if (!_acl_entry_matches(a1, ACL_USER_OBJ, 0,
 639                     ACL_ENTRY_TYPE_DENY))
 640                         must_append = 1;
 641                 if (!_acl_entry_matches(a2, ACL_USER_OBJ, ACL_WRITE_ACL |
 642                     ACL_WRITE_OWNER | ACL_WRITE_ATTRIBUTES |
 643                     ACL_WRITE_NAMED_ATTRS, ACL_ENTRY_TYPE_ALLOW))
 644                         must_append = 1;
 645                 if (!_acl_entry_matches(a3, ACL_GROUP_OBJ, 0,
 646                     ACL_ENTRY_TYPE_DENY))
 647                         must_append = 1;
 648                 if (!_acl_entry_matches(a4, ACL_GROUP_OBJ, 0,
 649                     ACL_ENTRY_TYPE_ALLOW))
 650                         must_append = 1;
 651                 if (!_acl_entry_matches(a5, ACL_EVERYONE, ACL_WRITE_ACL |
 652                     ACL_WRITE_OWNER | ACL_WRITE_ATTRIBUTES |
 653                     ACL_WRITE_NAMED_ATTRS, ACL_ENTRY_TYPE_DENY))
 654                         must_append = 1;
 655                 if (!_acl_entry_matches(a6, ACL_EVERYONE, ACL_READ_ACL |
 656                     ACL_READ_ATTRIBUTES | ACL_READ_NAMED_ATTRS |
 657                     ACL_SYNCHRONIZE, ACL_ENTRY_TYPE_ALLOW))
 658                         must_append = 1;
 659         }
 660
 661         if (must_append) {
 662                 KASSERT(aclp->acl_cnt + 6 <= ACL_MAX_ENTRIES,
 663                     ("aclp->acl_cnt <= ACL_MAX_ENTRIES"));
 664
 665                 a1 = _acl_append(aclp, ACL_USER_OBJ, 0, ACL_ENTRY_TYPE_DENY);
 666                 a2 = _acl_append(aclp, ACL_USER_OBJ, ACL_WRITE_ACL |
 667                     ACL_WRITE_OWNER | ACL_WRITE_ATTRIBUTES |
 668                     ACL_WRITE_NAMED_ATTRS, ACL_ENTRY_TYPE_ALLOW);
 669                 a3 = _acl_append(aclp, ACL_GROUP_OBJ, 0, ACL_ENTRY_TYPE_DENY);
 670                 a4 = _acl_append(aclp, ACL_GROUP_OBJ, 0, ACL_ENTRY_TYPE_ALLOW);
 671                 a5 = _acl_append(aclp, ACL_EVERYONE, ACL_WRITE_ACL |
 672                     ACL_WRITE_OWNER | ACL_WRITE_ATTRIBUTES |
 673                     ACL_WRITE_NAMED_ATTRS, ACL_ENTRY_TYPE_DENY);
 674                 a6 = _acl_append(aclp, ACL_EVERYONE, ACL_READ_ACL |
 675                     ACL_READ_ATTRIBUTES | ACL_READ_NAMED_ATTRS |
 676                     ACL_SYNCHRONIZE, ACL_ENTRY_TYPE_ALLOW);
 677
 678                 KASSERT(a1 != NULL && a2 != NULL && a3 != NULL && a4 != NULL &&
 679                     a5 != NULL && a6 != NULL, ("couldn't append to ACL."));
 680         }
 681
 682         /*
 683          * 3. The final six ACEs are adjusted according to the incoming mode.
 684          */
 685         if (mode & S_IRUSR)
 686                 a2->ae_perm |= ACL_READ_DATA;
 687         else
 688                 a1->ae_perm |= ACL_READ_DATA;
 689         if (mode & S_IWUSR)
 690                 a2->ae_perm |= (ACL_WRITE_DATA | ACL_APPEND_DATA);
 691         else
 692                 a1->ae_perm |= (ACL_WRITE_DATA | ACL_APPEND_DATA);
 693         if (mode & S_IXUSR)
 694                 a2->ae_perm |= ACL_EXECUTE;
 695         else
 696                 a1->ae_perm |= ACL_EXECUTE;
 697
 698         if (mode & S_IRGRP)
 699                 a4->ae_perm |= ACL_READ_DATA;
 700         else
 701                 a3->ae_perm |= ACL_READ_DATA;
 702         if (mode & S_IWGRP)
 703                 a4->ae_perm |= (ACL_WRITE_DATA | ACL_APPEND_DATA);
 704         else
 705                 a3->ae_perm |= (ACL_WRITE_DATA | ACL_APPEND_DATA);
 706         if (mode & S_IXGRP)
 707                 a4->ae_perm |= ACL_EXECUTE;
 708         else
 709                 a3->ae_perm |= ACL_EXECUTE;
 710
 711         if (mode & S_IROTH)
 712                 a6->ae_perm |= ACL_READ_DATA;
 713         else
 714                 a5->ae_perm |= ACL_READ_DATA;
 715         if (mode & S_IWOTH)
 716                 a6->ae_perm |= (ACL_WRITE_DATA | ACL_APPEND_DATA);
 717         else
 718                 a5->ae_perm |= (ACL_WRITE_DATA | ACL_APPEND_DATA);
 719         if (mode & S_IXOTH)
 720                 a6->ae_perm |= ACL_EXECUTE;
 721         else
 722                 a5->ae_perm |= ACL_EXECUTE;
 723 }
 724
 725 void
 726 acl_nfs4_sync_mode_from_acl(mode_t *_mode, const struct acl *aclp)
 727 {
 728         int i;
 729         mode_t old_mode = *_mode, mode = 0, seen = 0;
 730         const struct acl_entry *entry;
 731
 732         KASSERT(aclp->acl_cnt <= ACL_MAX_ENTRIES,
 733             ("aclp->acl_cnt <= ACL_MAX_ENTRIES"));
 734
 735         /*
 736          * NFSv4 Minor Version 1, draft-ietf-nfsv4-minorversion1-03.txt
 737          *
 738          * 3.16.6.1. Recomputing mode upon SETATTR of ACL
 739          */
 740
 741         for (i = 0; i < aclp->acl_cnt; i++) {
 742                 entry = &(aclp->acl_entry[i]);
 743
 744                 if (entry->ae_entry_type != ACL_ENTRY_TYPE_ALLOW &&
 745                     entry->ae_entry_type != ACL_ENTRY_TYPE_DENY)
 746                         continue;
 747
 748                 if (entry->ae_flags & ACL_ENTRY_INHERIT_ONLY)
 749                         continue;
 750
 751                 if (entry->ae_tag == ACL_USER_OBJ) {
 752                         if ((entry->ae_perm & ACL_READ_DATA) &&
 753                             ((seen & S_IRUSR) == 0)) {
 754                                 seen |= S_IRUSR;
 755                                 if (entry->ae_entry_type == ACL_ENTRY_TYPE_ALLOW)
 756                                         mode |= S_IRUSR;
 757                         }
 758                         if ((entry->ae_perm & ACL_WRITE_DATA) &&
 759                              ((seen & S_IWUSR) == 0)) {
 760                                 seen |= S_IWUSR;
 761                                 if (entry->ae_entry_type == ACL_ENTRY_TYPE_ALLOW)
 762                                         mode |= S_IWUSR;
 763                         }
 764                         if ((entry->ae_perm & ACL_EXECUTE) &&
 765                             ((seen & S_IXUSR) == 0)) {
 766                                 seen |= S_IXUSR;
 767                                 if (entry->ae_entry_type == ACL_ENTRY_TYPE_ALLOW)
 768                                         mode |= S_IXUSR;
 769                         }
 770                 } else if (entry->ae_tag == ACL_GROUP_OBJ) {
 771                         if ((entry->ae_perm & ACL_READ_DATA) &&
 772                             ((seen & S_IRGRP) == 0)) {
 773                                 seen |= S_IRGRP;
 774                                 if (entry->ae_entry_type == ACL_ENTRY_TYPE_ALLOW)
 775                                         mode |= S_IRGRP;
 776                         }
 777                         if ((entry->ae_perm & ACL_WRITE_DATA) &&
 778                             ((seen & S_IWGRP) == 0)) {
 779                                 seen |= S_IWGRP;
 780                                 if (entry->ae_entry_type == ACL_ENTRY_TYPE_ALLOW)
 781                                         mode |= S_IWGRP;
 782                         }
 783                         if ((entry->ae_perm & ACL_EXECUTE) &&
 784                             ((seen & S_IXGRP) == 0)) {
 785                                 seen |= S_IXGRP;
 786                                 if (entry->ae_entry_type == ACL_ENTRY_TYPE_ALLOW)
 787                                         mode |= S_IXGRP;
 788                         }
 789                 } else if (entry->ae_tag == ACL_EVERYONE) {
 790                         if (entry->ae_perm & ACL_READ_DATA) {
 791                                 if ((seen & S_IRUSR) == 0) {
 792                                         seen |= S_IRUSR;
 793                                         if (entry->ae_entry_type == ACL_ENTRY_TYPE_ALLOW)
 794                                                 mode |= S_IRUSR;
 795                                 }
 796                                 if ((seen & S_IRGRP) == 0) {
 797                                         seen |= S_IRGRP;
 798                                         if (entry->ae_entry_type == ACL_ENTRY_TYPE_ALLOW)
 799                                                 mode |= S_IRGRP;
 800                                 }
 801                                 if ((seen & S_IROTH) == 0) {
 802                                         seen |= S_IROTH;
 803                                         if (entry->ae_entry_type == ACL_ENTRY_TYPE_ALLOW)
 804                                                 mode |= S_IROTH;
 805                                 }
 806                         }
 807                         if (entry->ae_perm & ACL_WRITE_DATA) {
 808                                 if ((seen & S_IWUSR) == 0) {
 809                                         seen |= S_IWUSR;
 810                                         if (entry->ae_entry_type == ACL_ENTRY_TYPE_ALLOW)
 811                                                 mode |= S_IWUSR;
 812                                 }
 813                                 if ((seen & S_IWGRP) == 0) {
 814                                         seen |= S_IWGRP;
 815                                         if (entry->ae_entry_type == ACL_ENTRY_TYPE_ALLOW)
 816                                                 mode |= S_IWGRP;
 817                                 }
 818                                 if ((seen & S_IWOTH) == 0) {
 819                                         seen |= S_IWOTH;
 820                                         if (entry->ae_entry_type == ACL_ENTRY_TYPE_ALLOW)
 821                                                 mode |= S_IWOTH;
 822                                 }
 823                         }
 824                         if (entry->ae_perm & ACL_EXECUTE) {
 825                                 if ((seen & S_IXUSR) == 0) {
 826                                         seen |= S_IXUSR;
 827                                         if (entry->ae_entry_type == ACL_ENTRY_TYPE_ALLOW)
 828                                                 mode |= S_IXUSR;
 829                                 }
 830                                 if ((seen & S_IXGRP) == 0) {
 831                                         seen |= S_IXGRP;
 832                                         if (entry->ae_entry_type == ACL_ENTRY_TYPE_ALLOW)
 833                                                 mode |= S_IXGRP;
 834                                 }
 835                                 if ((seen & S_IXOTH) == 0) {
 836                                         seen |= S_IXOTH;
 837                                         if (entry->ae_entry_type == ACL_ENTRY_TYPE_ALLOW)
 838                                                 mode |= S_IXOTH;
 839                                 }
 840                         }
 841                 }
 842         }
 843
 844         *_mode = mode | (old_mode & ACL_PRESERVE_MASK);
 845 }
 846
 847 void
 848 acl_nfs4_compute_inherited_acl(const struct acl *parent_aclp,
 849     struct acl *child_aclp, mode_t mode, int file_owner_id,
 850     int is_directory)
 851 {
 852         int i, flags;
 853         const struct acl_entry *parent_entry;
 854         struct acl_entry *entry, *copy;
 855
 856         KASSERT(child_aclp->acl_cnt == 0, ("child_aclp->acl_cnt == 0"));
 857         KASSERT(parent_aclp->acl_cnt <= ACL_MAX_ENTRIES,
 858             ("parent_aclp->acl_cnt <= ACL_MAX_ENTRIES"));
 859
 860         /*
 861          * NFSv4 Minor Version 1, draft-ietf-nfsv4-minorversion1-03.txt
 862          *
 863          * 3.16.6.2. Applying the mode given to CREATE or OPEN
 864          *           to an inherited ACL
 865          */
 866
 867         /*
 868          * 1. Form an ACL that is the concatenation of all inheritable ACEs.
 869          */
 870         for (i = 0; i < parent_aclp->acl_cnt; i++) {
 871                 parent_entry = &(parent_aclp->acl_entry[i]);
 872                 flags = parent_entry->ae_flags;
 873
 874                 /*
 875                  * Entry is not inheritable at all.
 876                  */
 877                 if ((flags & (ACL_ENTRY_DIRECTORY_INHERIT |
 878                     ACL_ENTRY_FILE_INHERIT)) == 0)
 879                         continue;
 880
 881                 /*
 882                  * We're creating a file, but entry is not inheritable
 883                  * by files.
 884                  */
 885                 if (!is_directory && (flags & ACL_ENTRY_FILE_INHERIT) == 0)
 886                         continue;
 887
 888                 /*
 889                  * Entry is inheritable only by files, but has NO_PROPAGATE
 890                  * flag set, and we're creating a directory, so it wouldn't
 891                  * propagate to any file in that directory anyway.
 892                  */
 893                 if (is_directory &&
 894                     (flags & ACL_ENTRY_DIRECTORY_INHERIT) == 0 &&
 895                     (flags & ACL_ENTRY_NO_PROPAGATE_INHERIT))
 896                         continue;
 897
 898                 KASSERT(child_aclp->acl_cnt + 1 <= ACL_MAX_ENTRIES,
 899                     ("child_aclp->acl_cnt + 1 <= ACL_MAX_ENTRIES"));
 900                 child_aclp->acl_entry[child_aclp->acl_cnt] = *parent_entry;
 901                 child_aclp->acl_cnt++;
 902         }
 903
 904         /*
 905          * 2. For each entry in the new ACL, adjust its flags, possibly
 906          *    creating two entries in place of one.
 907          */
 908         for (i = 0; i < child_aclp->acl_cnt; i++) {
 909                 entry = &(child_aclp->acl_entry[i]);
 910
 911                 /*
 912                  * This is not in the specification, but SunOS
 913                  * apparently does that.
 914                  */
 915                 if (((entry->ae_flags & ACL_ENTRY_NO_PROPAGATE_INHERIT) ||
 916                     !is_directory) &&
 917                     entry->ae_entry_type == ACL_ENTRY_TYPE_ALLOW)
 918                         entry->ae_perm &= ~(ACL_WRITE_ACL | ACL_WRITE_OWNER);
 919
 920                 /*
 921                  * 2.A. If the ACL_ENTRY_NO_PROPAGATE_INHERIT is set, or if the object
 922                  *      being created is not a directory, then clear the
 923                  *      following flags: ACL_ENTRY_NO_PROPAGATE_INHERIT,
 924                  *      ACL_ENTRY_FILE_INHERIT, ACL_ENTRY_DIRECTORY_INHERIT,
 925                  *      ACL_ENTRY_INHERIT_ONLY.
 926                  */
 927                 if (entry->ae_flags & ACL_ENTRY_NO_PROPAGATE_INHERIT ||
 928                     !is_directory) {
 929                         entry->ae_flags &= ~(ACL_ENTRY_NO_PROPAGATE_INHERIT |
 930                         ACL_ENTRY_FILE_INHERIT | ACL_ENTRY_DIRECTORY_INHERIT |
 931                         ACL_ENTRY_INHERIT_ONLY);
 932
 933                         /*
 934                          * Continue on to the next ACE.
 935                          */
 936                         continue;
 937                 }
 938
 939                 /*
 940                  * 2.B. If the object is a directory and ACL_ENTRY_FILE_INHERIT
 941                  *      is set, but ACL_ENTRY_NO_PROPAGATE_INHERIT is not set, ensure
 942                  *      that ACL_ENTRY_INHERIT_ONLY is set.  Continue to the
 943                  *      next ACE.  Otherwise...
 944                  */
 945                 /*
 946                  * XXX: Read it again and make sure what does the "otherwise"
 947                  *      apply to.
 948                  */
 949                 if (is_directory &&
 950                     (entry->ae_flags & ACL_ENTRY_FILE_INHERIT) &&
 951                     ((entry->ae_flags & ACL_ENTRY_DIRECTORY_INHERIT) == 0)) {
 952                         entry->ae_flags |= ACL_ENTRY_INHERIT_ONLY;
 953                         continue;
 954                 }
 955
 956                 /*
 957                  * 2.C. If the type of the ACE is neither ALLOW nor deny,
 958                  *      then continue.
 959                  */
 960                 if (entry->ae_entry_type != ACL_ENTRY_TYPE_ALLOW &&
 961                     entry->ae_entry_type != ACL_ENTRY_TYPE_DENY)
 962                         continue;
 963
 964                 /*
 965                  * 2.D. Copy the original ACE into a second, adjacent ACE.
 966                  */
 967                 copy = _acl_duplicate_entry(child_aclp, i);
 968
 969                 /*
 970                  * 2.E. On the first ACE, ensure that ACL_ENTRY_INHERIT_ONLY
 971                  *      is set.
 972                  */
 973                 entry->ae_flags |= ACL_ENTRY_INHERIT_ONLY;
 974
 975                 /*
 976                  * 2.F. On the second ACE, clear the following flags:
 977                  *      ACL_ENTRY_NO_PROPAGATE_INHERIT, ACL_ENTRY_FILE_INHERIT,
 978                  *      ACL_ENTRY_DIRECTORY_INHERIT, ACL_ENTRY_INHERIT_ONLY.
 979                  */
 980                 copy->ae_flags &= ~(ACL_ENTRY_NO_PROPAGATE_INHERIT |
 981                     ACL_ENTRY_FILE_INHERIT | ACL_ENTRY_DIRECTORY_INHERIT |
 982                     ACL_ENTRY_INHERIT_ONLY);
 983
 984                 /*
 985                  * 2.G. On the second ACE, if the type is ALLOW,
 986                  *      an implementation MAY clear the following
 987                  *      mask bits: ACL_WRITE_ACL, ACL_WRITE_OWNER.
 988                  */
 989                 if (copy->ae_entry_type == ACL_ENTRY_TYPE_ALLOW)
 990                         copy->ae_perm &= ~(ACL_WRITE_ACL | ACL_WRITE_OWNER);
 991
 992                 /*
 993                  * Increment the counter to skip the copied entry.
 994                  */
 995                 i++;
 996         }
 997
 998         /*
 999          * 3. To ensure that the mode is honored, apply the algorithm describe
1000          *    in Section 2.16.6.3, using the mode that is to be used for file
1001          *    creation.
1002          */
1003         acl_nfs4_sync_acl_from_mode(child_aclp, mode, file_owner_id);
1004 }
1005
1006 #ifdef _KERNEL
1007 static int
1008 _acls_are_equal(const struct acl *a, const struct acl *b)
1009 {
1010         int i;
1011         const struct acl_entry *entrya, *entryb;
1012
1013         if (a->acl_cnt != b->acl_cnt)
1014                 return (0);
1015
1016         for (i = 0; i < b->acl_cnt; i++) {
1017                 entrya = &(a->acl_entry[i]);
1018                 entryb = &(b->acl_entry[i]);
1019
1020                 if (entrya->ae_tag != entryb->ae_tag ||
1021                     entrya->ae_id != entryb->ae_id ||
1022                     entrya->ae_perm != entryb->ae_perm ||
1023                     entrya->ae_entry_type != entryb->ae_entry_type ||
1024                     entrya->ae_flags != entryb->ae_flags)
1025                         return (0);
1026         }
1027
1028         return (1);
1029 }
1030
1031 /*
1032  * This routine is used to determine whether to remove entry_type attribute
1033  * that stores ACL contents.
1034  */
1035 int
1036 acl_nfs4_is_trivial(const struct acl *aclp, int file_owner_id)
1037 {
1038         int trivial;
1039         mode_t tmpmode = 0;
1040         struct acl *tmpaclp;
1041
1042         if (aclp->acl_cnt != 6)
1043                 return (0);
1044
1045         /*
1046          * Compute the mode from the ACL, then compute new ACL from that mode.
1047          * If the ACLs are identical, then the ACL is trivial.
1048          *
1049          * XXX: I guess there is a faster way to do this.  However, even
1050          *      this slow implementation significantly speeds things up
1051          *      for files that don't have any entry_type ACL entries - it's
1052          *      critical for performance to not use EA when they are not
1053          *      needed.
1054          */
1055         tmpaclp = acl_alloc(M_WAITOK | M_ZERO);
1056         acl_nfs4_sync_mode_from_acl(&tmpmode, aclp);
1057         acl_nfs4_sync_acl_from_mode(tmpaclp, tmpmode, file_owner_id);
1058         trivial = _acls_are_equal(aclp, tmpaclp);
1059         acl_free(tmpaclp);
1060
1061         return (trivial);
1062 }
1063 #endif /* _KERNEL */
1064
1065 int
1066 acl_nfs4_check(const struct acl *aclp, int is_directory)
1067 {
1068         int i;
1069         const struct acl_entry *entry;
1070
1071         /*
1072          * The spec doesn't seem to say anything about ACL validity.
1073          * It seems there is not much to do here.  There is even no need
1074          * to count "owner@" or "everyone@" (ACL_USER_OBJ and ACL_EVERYONE)
1075          * entries, as there can be several of them and that's perfectly
1076          * valid.  There can be none of them too.  Really.
1077          */
1078
1079         if (aclp->acl_cnt > ACL_MAX_ENTRIES || aclp->acl_cnt <= 0)
1080                 return (EINVAL);
1081
1082         for (i = 0; i < aclp->acl_cnt; i++) {
1083                 entry = &(aclp->acl_entry[i]);
1084
1085                 switch (entry->ae_tag) {
1086                 case ACL_USER_OBJ:
1087                 case ACL_GROUP_OBJ:
1088                 case ACL_EVERYONE:
1089                         if (entry->ae_id != ACL_UNDEFINED_ID)
1090                                 return (EINVAL);
1091                         break;
1092
1093                 case ACL_USER:
1094                 case ACL_GROUP:
1095                         if (entry->ae_id == ACL_UNDEFINED_ID)
1096                                 return (EINVAL);
1097                         break;
1098
1099                 default:
1100                         return (EINVAL);
1101                 }
1102
1103                 if ((entry->ae_perm | ACL_NFS4_PERM_BITS) != ACL_NFS4_PERM_BITS)
1104                         return (EINVAL);
1105
1106                 /*
1107                  * Disallow ACL_ENTRY_TYPE_AUDIT and ACL_ENTRY_TYPE_ALARM for now.
1108                  */
1109                 if (entry->ae_entry_type != ACL_ENTRY_TYPE_ALLOW &&
1110                     entry->ae_entry_type != ACL_ENTRY_TYPE_DENY)
1111                         return (EINVAL);
1112
1113                 if ((entry->ae_flags | ACL_FLAGS_BITS) != ACL_FLAGS_BITS)
1114                         return (EINVAL);
1115
1116                 /* Disallow unimplemented flags. */
1117                 if (entry->ae_flags & (ACL_ENTRY_SUCCESSFUL_ACCESS |
1118                     ACL_ENTRY_FAILED_ACCESS))
1119                         return (EINVAL);
1120
1121                 /* Disallow flags not allowed for ordinary files. */
1122                 if (!is_directory) {
1123                         if (entry->ae_flags & (ACL_ENTRY_FILE_INHERIT |
1124                             ACL_ENTRY_DIRECTORY_INHERIT |
1125                             ACL_ENTRY_NO_PROPAGATE_INHERIT | ACL_ENTRY_INHERIT_ONLY))
1126                                 return (EINVAL);
1127                 }
1128         }
1129
1130         return (0);
1131 }