1 /* 2 * Common NFSv4 ACL handling code. 3 * 4 * Copyright (c) 2002, 2003 The Regents of the University of Michigan. 5 * All rights reserved. 6 * 7 * Marius Aamodt Eriksen <marius@umich.edu> 8 * Jeff Sedlak <jsedlak@umich.edu> 9 * J. Bruce Fields <bfields@umich.edu> 10 * 11 * Redistribution and use in source and binary forms, with or without 12 * modification, are permitted provided that the following conditions 13 * are met: 14 * 15 * 1. Redistributions of source code must retain the above copyright 16 * notice, this list of conditions and the following disclaimer. 17 * 2. Redistributions in binary form must reproduce the above copyright 18 * notice, this list of conditions and the following disclaimer in the 19 * documentation and/or other materials provided with the distribution. 20 * 3. Neither the name of the University nor the names of its 21 * contributors may be used to endorse or promote products derived 22 * from this software without specific prior written permission. 23 * 24 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED 25 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 26 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE 27 * DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 29 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 30 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR 31 * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF 32 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING 33 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS 34 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 35 */ 36 37 #include <linux/slab.h> 38 #include <linux/nfs_fs.h> 39 #include "nfsfh.h" 40 #include "nfsd.h" 41 #include "acl.h" 42 #include "vfs.h" 43 44 #define NFS4_ACL_TYPE_DEFAULT 0x01 45 #define NFS4_ACL_DIR 0x02 46 #define NFS4_ACL_OWNER 0x04 47 48 /* mode bit translations: */ 49 #define NFS4_READ_MODE (NFS4_ACE_READ_DATA) 50 #define NFS4_WRITE_MODE (NFS4_ACE_WRITE_DATA | NFS4_ACE_APPEND_DATA) 51 #define NFS4_EXECUTE_MODE NFS4_ACE_EXECUTE 52 #define NFS4_ANYONE_MODE (NFS4_ACE_READ_ATTRIBUTES | NFS4_ACE_READ_ACL | NFS4_ACE_SYNCHRONIZE) 53 #define NFS4_OWNER_MODE (NFS4_ACE_WRITE_ATTRIBUTES | NFS4_ACE_WRITE_ACL) 54 55 /* flags used to simulate posix default ACLs */ 56 #define NFS4_INHERITANCE_FLAGS (NFS4_ACE_FILE_INHERIT_ACE \ 57 | NFS4_ACE_DIRECTORY_INHERIT_ACE) 58 59 #define NFS4_SUPPORTED_FLAGS (NFS4_INHERITANCE_FLAGS \ 60 | NFS4_ACE_INHERIT_ONLY_ACE \ 61 | NFS4_ACE_IDENTIFIER_GROUP) 62 63 static u32 64 mask_from_posix(unsigned short perm, unsigned int flags) 65 { 66 int mask = NFS4_ANYONE_MODE; 67 68 if (flags & NFS4_ACL_OWNER) 69 mask |= NFS4_OWNER_MODE; 70 if (perm & ACL_READ) 71 mask |= NFS4_READ_MODE; 72 if (perm & ACL_WRITE) 73 mask |= NFS4_WRITE_MODE; 74 if ((perm & ACL_WRITE) && (flags & NFS4_ACL_DIR)) 75 mask |= NFS4_ACE_DELETE_CHILD; 76 if (perm & ACL_EXECUTE) 77 mask |= NFS4_EXECUTE_MODE; 78 return mask; 79 } 80 81 static u32 82 deny_mask_from_posix(unsigned short perm, u32 flags) 83 { 84 u32 mask = 0; 85 86 if (perm & ACL_READ) 87 mask |= NFS4_READ_MODE; 88 if (perm & ACL_WRITE) 89 mask |= NFS4_WRITE_MODE; 90 if ((perm & ACL_WRITE) && (flags & NFS4_ACL_DIR)) 91 mask |= NFS4_ACE_DELETE_CHILD; 92 if (perm & ACL_EXECUTE) 93 mask |= NFS4_EXECUTE_MODE; 94 return mask; 95 } 96 97 /* XXX: modify functions to return NFS errors; they're only ever 98 * used by nfs code, after all.... */ 99 100 /* We only map from NFSv4 to POSIX ACLs when setting ACLs, when we err on the 101 * side of being more restrictive, so the mode bit mapping below is 102 * pessimistic. An optimistic version would be needed to handle DENY's, 103 * but we espect to coalesce all ALLOWs and DENYs before mapping to mode 104 * bits. */ 105 106 static void 107 low_mode_from_nfs4(u32 perm, unsigned short *mode, unsigned int flags) 108 { 109 u32 write_mode = NFS4_WRITE_MODE; 110 111 if (flags & NFS4_ACL_DIR) 112 write_mode |= NFS4_ACE_DELETE_CHILD; 113 *mode = 0; 114 if ((perm & NFS4_READ_MODE) == NFS4_READ_MODE) 115 *mode |= ACL_READ; 116 if ((perm & write_mode) == write_mode) 117 *mode |= ACL_WRITE; 118 if ((perm & NFS4_EXECUTE_MODE) == NFS4_EXECUTE_MODE) 119 *mode |= ACL_EXECUTE; 120 } 121 122 static short ace2type(struct nfs4_ace *); 123 static void _posix_to_nfsv4_one(struct posix_acl *, struct nfs4_acl *, 124 unsigned int); 125 126 int 127 nfsd4_get_nfs4_acl(struct svc_rqst *rqstp, struct dentry *dentry, 128 struct nfs4_acl **acl) 129 { 130 struct inode *inode = d_inode(dentry); 131 int error = 0; 132 struct posix_acl *pacl = NULL, *dpacl = NULL; 133 unsigned int flags = 0; 134 int size = 0; 135 136 pacl = get_acl(inode, ACL_TYPE_ACCESS); 137 if (!pacl) 138 pacl = posix_acl_from_mode(inode->i_mode, GFP_KERNEL); 139 140 if (IS_ERR(pacl)) 141 return PTR_ERR(pacl); 142 143 /* allocate for worst case: one (deny, allow) pair each: */ 144 size += 2 * pacl->a_count; 145 146 if (S_ISDIR(inode->i_mode)) { 147 flags = NFS4_ACL_DIR; 148 dpacl = get_acl(inode, ACL_TYPE_DEFAULT); 149 if (IS_ERR(dpacl)) { 150 error = PTR_ERR(dpacl); 151 goto rel_pacl; 152 } 153 154 if (dpacl) 155 size += 2 * dpacl->a_count; 156 } 157 158 *acl = kmalloc(nfs4_acl_bytes(size), GFP_KERNEL); 159 if (*acl == NULL) { 160 error = -ENOMEM; 161 goto out; 162 } 163 (*acl)->naces = 0; 164 165 _posix_to_nfsv4_one(pacl, *acl, flags & ~NFS4_ACL_TYPE_DEFAULT); 166 167 if (dpacl) 168 _posix_to_nfsv4_one(dpacl, *acl, flags | NFS4_ACL_TYPE_DEFAULT); 169 170 out: 171 posix_acl_release(dpacl); 172 rel_pacl: 173 posix_acl_release(pacl); 174 return error; 175 } 176 177 struct posix_acl_summary { 178 unsigned short owner; 179 unsigned short users; 180 unsigned short group; 181 unsigned short groups; 182 unsigned short other; 183 unsigned short mask; 184 }; 185 186 static void 187 summarize_posix_acl(struct posix_acl *acl, struct posix_acl_summary *pas) 188 { 189 struct posix_acl_entry *pa, *pe; 190 191 /* 192 * Only pas.users and pas.groups need initialization; previous 193 * posix_acl_valid() calls ensure that the other fields will be 194 * initialized in the following loop. But, just to placate gcc: 195 */ 196 memset(pas, 0, sizeof(*pas)); 197 pas->mask = 07; 198 199 pe = acl->a_entries + acl->a_count; 200 201 FOREACH_ACL_ENTRY(pa, acl, pe) { 202 switch (pa->e_tag) { 203 case ACL_USER_OBJ: 204 pas->owner = pa->e_perm; 205 break; 206 case ACL_GROUP_OBJ: 207 pas->group = pa->e_perm; 208 break; 209 case ACL_USER: 210 pas->users |= pa->e_perm; 211 break; 212 case ACL_GROUP: 213 pas->groups |= pa->e_perm; 214 break; 215 case ACL_OTHER: 216 pas->other = pa->e_perm; 217 break; 218 case ACL_MASK: 219 pas->mask = pa->e_perm; 220 break; 221 } 222 } 223 /* We'll only care about effective permissions: */ 224 pas->users &= pas->mask; 225 pas->group &= pas->mask; 226 pas->groups &= pas->mask; 227 } 228 229 /* We assume the acl has been verified with posix_acl_valid. */ 230 static void 231 _posix_to_nfsv4_one(struct posix_acl *pacl, struct nfs4_acl *acl, 232 unsigned int flags) 233 { 234 struct posix_acl_entry *pa, *group_owner_entry; 235 struct nfs4_ace *ace; 236 struct posix_acl_summary pas; 237 unsigned short deny; 238 int eflag = ((flags & NFS4_ACL_TYPE_DEFAULT) ? 239 NFS4_INHERITANCE_FLAGS | NFS4_ACE_INHERIT_ONLY_ACE : 0); 240 241 BUG_ON(pacl->a_count < 3); 242 summarize_posix_acl(pacl, &pas); 243 244 pa = pacl->a_entries; 245 ace = acl->aces + acl->naces; 246 247 /* We could deny everything not granted by the owner: */ 248 deny = ~pas.owner; 249 /* 250 * but it is equivalent (and simpler) to deny only what is not 251 * granted by later entries: 252 */ 253 deny &= pas.users | pas.group | pas.groups | pas.other; 254 if (deny) { 255 ace->type = NFS4_ACE_ACCESS_DENIED_ACE_TYPE; 256 ace->flag = eflag; 257 ace->access_mask = deny_mask_from_posix(deny, flags); 258 ace->whotype = NFS4_ACL_WHO_OWNER; 259 ace++; 260 acl->naces++; 261 } 262 263 ace->type = NFS4_ACE_ACCESS_ALLOWED_ACE_TYPE; 264 ace->flag = eflag; 265 ace->access_mask = mask_from_posix(pa->e_perm, flags | NFS4_ACL_OWNER); 266 ace->whotype = NFS4_ACL_WHO_OWNER; 267 ace++; 268 acl->naces++; 269 pa++; 270 271 while (pa->e_tag == ACL_USER) { 272 deny = ~(pa->e_perm & pas.mask); 273 deny &= pas.groups | pas.group | pas.other; 274 if (deny) { 275 ace->type = NFS4_ACE_ACCESS_DENIED_ACE_TYPE; 276 ace->flag = eflag; 277 ace->access_mask = deny_mask_from_posix(deny, flags); 278 ace->whotype = NFS4_ACL_WHO_NAMED; 279 ace->who_uid = pa->e_uid; 280 ace++; 281 acl->naces++; 282 } 283 ace->type = NFS4_ACE_ACCESS_ALLOWED_ACE_TYPE; 284 ace->flag = eflag; 285 ace->access_mask = mask_from_posix(pa->e_perm & pas.mask, 286 flags); 287 ace->whotype = NFS4_ACL_WHO_NAMED; 288 ace->who_uid = pa->e_uid; 289 ace++; 290 acl->naces++; 291 pa++; 292 } 293 294 /* In the case of groups, we apply allow ACEs first, then deny ACEs, 295 * since a user can be in more than one group. */ 296 297 /* allow ACEs */ 298 299 group_owner_entry = pa; 300 301 ace->type = NFS4_ACE_ACCESS_ALLOWED_ACE_TYPE; 302 ace->flag = eflag; 303 ace->access_mask = mask_from_posix(pas.group, flags); 304 ace->whotype = NFS4_ACL_WHO_GROUP; 305 ace++; 306 acl->naces++; 307 pa++; 308 309 while (pa->e_tag == ACL_GROUP) { 310 ace->type = NFS4_ACE_ACCESS_ALLOWED_ACE_TYPE; 311 ace->flag = eflag | NFS4_ACE_IDENTIFIER_GROUP; 312 ace->access_mask = mask_from_posix(pa->e_perm & pas.mask, 313 flags); 314 ace->whotype = NFS4_ACL_WHO_NAMED; 315 ace->who_gid = pa->e_gid; 316 ace++; 317 acl->naces++; 318 pa++; 319 } 320 321 /* deny ACEs */ 322 323 pa = group_owner_entry; 324 325 deny = ~pas.group & pas.other; 326 if (deny) { 327 ace->type = NFS4_ACE_ACCESS_DENIED_ACE_TYPE; 328 ace->flag = eflag; 329 ace->access_mask = deny_mask_from_posix(deny, flags); 330 ace->whotype = NFS4_ACL_WHO_GROUP; 331 ace++; 332 acl->naces++; 333 } 334 pa++; 335 336 while (pa->e_tag == ACL_GROUP) { 337 deny = ~(pa->e_perm & pas.mask); 338 deny &= pas.other; 339 if (deny) { 340 ace->type = NFS4_ACE_ACCESS_DENIED_ACE_TYPE; 341 ace->flag = eflag | NFS4_ACE_IDENTIFIER_GROUP; 342 ace->access_mask = deny_mask_from_posix(deny, flags); 343 ace->whotype = NFS4_ACL_WHO_NAMED; 344 ace->who_gid = pa->e_gid; 345 ace++; 346 acl->naces++; 347 } 348 pa++; 349 } 350 351 if (pa->e_tag == ACL_MASK) 352 pa++; 353 ace->type = NFS4_ACE_ACCESS_ALLOWED_ACE_TYPE; 354 ace->flag = eflag; 355 ace->access_mask = mask_from_posix(pa->e_perm, flags); 356 ace->whotype = NFS4_ACL_WHO_EVERYONE; 357 acl->naces++; 358 } 359 360 static bool 361 pace_gt(struct posix_acl_entry *pace1, struct posix_acl_entry *pace2) 362 { 363 if (pace1->e_tag != pace2->e_tag) 364 return pace1->e_tag > pace2->e_tag; 365 if (pace1->e_tag == ACL_USER) 366 return uid_gt(pace1->e_uid, pace2->e_uid); 367 if (pace1->e_tag == ACL_GROUP) 368 return gid_gt(pace1->e_gid, pace2->e_gid); 369 return false; 370 } 371 372 static void 373 sort_pacl_range(struct posix_acl *pacl, int start, int end) { 374 int sorted = 0, i; 375 376 /* We just do a bubble sort; easy to do in place, and we're not 377 * expecting acl's to be long enough to justify anything more. */ 378 while (!sorted) { 379 sorted = 1; 380 for (i = start; i < end; i++) { 381 if (pace_gt(&pacl->a_entries[i], 382 &pacl->a_entries[i+1])) { 383 sorted = 0; 384 swap(pacl->a_entries[i], 385 pacl->a_entries[i + 1]); 386 } 387 } 388 } 389 } 390 391 static void 392 sort_pacl(struct posix_acl *pacl) 393 { 394 /* posix_acl_valid requires that users and groups be in order 395 * by uid/gid. */ 396 int i, j; 397 398 /* no users or groups */ 399 if (!pacl || pacl->a_count <= 4) 400 return; 401 402 i = 1; 403 while (pacl->a_entries[i].e_tag == ACL_USER) 404 i++; 405 sort_pacl_range(pacl, 1, i-1); 406 407 BUG_ON(pacl->a_entries[i].e_tag != ACL_GROUP_OBJ); 408 j = ++i; 409 while (pacl->a_entries[j].e_tag == ACL_GROUP) 410 j++; 411 sort_pacl_range(pacl, i, j-1); 412 return; 413 } 414 415 /* 416 * While processing the NFSv4 ACE, this maintains bitmasks representing 417 * which permission bits have been allowed and which denied to a given 418 * entity: */ 419 struct posix_ace_state { 420 u32 allow; 421 u32 deny; 422 }; 423 424 struct posix_user_ace_state { 425 union { 426 kuid_t uid; 427 kgid_t gid; 428 }; 429 struct posix_ace_state perms; 430 }; 431 432 struct posix_ace_state_array { 433 int n; 434 struct posix_user_ace_state aces[]; 435 }; 436 437 /* 438 * While processing the NFSv4 ACE, this maintains the partial permissions 439 * calculated so far: */ 440 441 struct posix_acl_state { 442 int empty; 443 struct posix_ace_state owner; 444 struct posix_ace_state group; 445 struct posix_ace_state other; 446 struct posix_ace_state everyone; 447 struct posix_ace_state mask; /* Deny unused in this case */ 448 struct posix_ace_state_array *users; 449 struct posix_ace_state_array *groups; 450 }; 451 452 static int 453 init_state(struct posix_acl_state *state, int cnt) 454 { 455 int alloc; 456 457 memset(state, 0, sizeof(struct posix_acl_state)); 458 state->empty = 1; 459 /* 460 * In the worst case, each individual acl could be for a distinct 461 * named user or group, but we don't no which, so we allocate 462 * enough space for either: 463 */ 464 alloc = sizeof(struct posix_ace_state_array) 465 + cnt*sizeof(struct posix_user_ace_state); 466 state->users = kzalloc(alloc, GFP_KERNEL); 467 if (!state->users) 468 return -ENOMEM; 469 state->groups = kzalloc(alloc, GFP_KERNEL); 470 if (!state->groups) { 471 kfree(state->users); 472 return -ENOMEM; 473 } 474 return 0; 475 } 476 477 static void 478 free_state(struct posix_acl_state *state) { 479 kfree(state->users); 480 kfree(state->groups); 481 } 482 483 static inline void add_to_mask(struct posix_acl_state *state, struct posix_ace_state *astate) 484 { 485 state->mask.allow |= astate->allow; 486 } 487 488 static struct posix_acl * 489 posix_state_to_acl(struct posix_acl_state *state, unsigned int flags) 490 { 491 struct posix_acl_entry *pace; 492 struct posix_acl *pacl; 493 int nace; 494 int i; 495 496 /* 497 * ACLs with no ACEs are treated differently in the inheritable 498 * and effective cases: when there are no inheritable ACEs, 499 * calls ->set_acl with a NULL ACL structure. 500 */ 501 if (state->empty && (flags & NFS4_ACL_TYPE_DEFAULT)) 502 return NULL; 503 504 /* 505 * When there are no effective ACEs, the following will end 506 * up setting a 3-element effective posix ACL with all 507 * permissions zero. 508 */ 509 if (!state->users->n && !state->groups->n) 510 nace = 3; 511 else /* Note we also include a MASK ACE in this case: */ 512 nace = 4 + state->users->n + state->groups->n; 513 pacl = posix_acl_alloc(nace, GFP_KERNEL); 514 if (!pacl) 515 return ERR_PTR(-ENOMEM); 516 517 pace = pacl->a_entries; 518 pace->e_tag = ACL_USER_OBJ; 519 low_mode_from_nfs4(state->owner.allow, &pace->e_perm, flags); 520 521 for (i=0; i < state->users->n; i++) { 522 pace++; 523 pace->e_tag = ACL_USER; 524 low_mode_from_nfs4(state->users->aces[i].perms.allow, 525 &pace->e_perm, flags); 526 pace->e_uid = state->users->aces[i].uid; 527 add_to_mask(state, &state->users->aces[i].perms); 528 } 529 530 pace++; 531 pace->e_tag = ACL_GROUP_OBJ; 532 low_mode_from_nfs4(state->group.allow, &pace->e_perm, flags); 533 add_to_mask(state, &state->group); 534 535 for (i=0; i < state->groups->n; i++) { 536 pace++; 537 pace->e_tag = ACL_GROUP; 538 low_mode_from_nfs4(state->groups->aces[i].perms.allow, 539 &pace->e_perm, flags); 540 pace->e_gid = state->groups->aces[i].gid; 541 add_to_mask(state, &state->groups->aces[i].perms); 542 } 543 544 if (state->users->n || state->groups->n) { 545 pace++; 546 pace->e_tag = ACL_MASK; 547 low_mode_from_nfs4(state->mask.allow, &pace->e_perm, flags); 548 } 549 550 pace++; 551 pace->e_tag = ACL_OTHER; 552 low_mode_from_nfs4(state->other.allow, &pace->e_perm, flags); 553 554 return pacl; 555 } 556 557 static inline void allow_bits(struct posix_ace_state *astate, u32 mask) 558 { 559 /* Allow all bits in the mask not already denied: */ 560 astate->allow |= mask & ~astate->deny; 561 } 562 563 static inline void deny_bits(struct posix_ace_state *astate, u32 mask) 564 { 565 /* Deny all bits in the mask not already allowed: */ 566 astate->deny |= mask & ~astate->allow; 567 } 568 569 static int find_uid(struct posix_acl_state *state, kuid_t uid) 570 { 571 struct posix_ace_state_array *a = state->users; 572 int i; 573 574 for (i = 0; i < a->n; i++) 575 if (uid_eq(a->aces[i].uid, uid)) 576 return i; 577 /* Not found: */ 578 a->n++; 579 a->aces[i].uid = uid; 580 a->aces[i].perms.allow = state->everyone.allow; 581 a->aces[i].perms.deny = state->everyone.deny; 582 583 return i; 584 } 585 586 static int find_gid(struct posix_acl_state *state, kgid_t gid) 587 { 588 struct posix_ace_state_array *a = state->groups; 589 int i; 590 591 for (i = 0; i < a->n; i++) 592 if (gid_eq(a->aces[i].gid, gid)) 593 return i; 594 /* Not found: */ 595 a->n++; 596 a->aces[i].gid = gid; 597 a->aces[i].perms.allow = state->everyone.allow; 598 a->aces[i].perms.deny = state->everyone.deny; 599 600 return i; 601 } 602 603 static void deny_bits_array(struct posix_ace_state_array *a, u32 mask) 604 { 605 int i; 606 607 for (i=0; i < a->n; i++) 608 deny_bits(&a->aces[i].perms, mask); 609 } 610 611 static void allow_bits_array(struct posix_ace_state_array *a, u32 mask) 612 { 613 int i; 614 615 for (i=0; i < a->n; i++) 616 allow_bits(&a->aces[i].perms, mask); 617 } 618 619 static void process_one_v4_ace(struct posix_acl_state *state, 620 struct nfs4_ace *ace) 621 { 622 u32 mask = ace->access_mask; 623 int i; 624 625 state->empty = 0; 626 627 switch (ace2type(ace)) { 628 case ACL_USER_OBJ: 629 if (ace->type == NFS4_ACE_ACCESS_ALLOWED_ACE_TYPE) { 630 allow_bits(&state->owner, mask); 631 } else { 632 deny_bits(&state->owner, mask); 633 } 634 break; 635 case ACL_USER: 636 i = find_uid(state, ace->who_uid); 637 if (ace->type == NFS4_ACE_ACCESS_ALLOWED_ACE_TYPE) { 638 allow_bits(&state->users->aces[i].perms, mask); 639 } else { 640 deny_bits(&state->users->aces[i].perms, mask); 641 mask = state->users->aces[i].perms.deny; 642 deny_bits(&state->owner, mask); 643 } 644 break; 645 case ACL_GROUP_OBJ: 646 if (ace->type == NFS4_ACE_ACCESS_ALLOWED_ACE_TYPE) { 647 allow_bits(&state->group, mask); 648 } else { 649 deny_bits(&state->group, mask); 650 mask = state->group.deny; 651 deny_bits(&state->owner, mask); 652 deny_bits(&state->everyone, mask); 653 deny_bits_array(state->users, mask); 654 deny_bits_array(state->groups, mask); 655 } 656 break; 657 case ACL_GROUP: 658 i = find_gid(state, ace->who_gid); 659 if (ace->type == NFS4_ACE_ACCESS_ALLOWED_ACE_TYPE) { 660 allow_bits(&state->groups->aces[i].perms, mask); 661 } else { 662 deny_bits(&state->groups->aces[i].perms, mask); 663 mask = state->groups->aces[i].perms.deny; 664 deny_bits(&state->owner, mask); 665 deny_bits(&state->group, mask); 666 deny_bits(&state->everyone, mask); 667 deny_bits_array(state->users, mask); 668 deny_bits_array(state->groups, mask); 669 } 670 break; 671 case ACL_OTHER: 672 if (ace->type == NFS4_ACE_ACCESS_ALLOWED_ACE_TYPE) { 673 allow_bits(&state->owner, mask); 674 allow_bits(&state->group, mask); 675 allow_bits(&state->other, mask); 676 allow_bits(&state->everyone, mask); 677 allow_bits_array(state->users, mask); 678 allow_bits_array(state->groups, mask); 679 } else { 680 deny_bits(&state->owner, mask); 681 deny_bits(&state->group, mask); 682 deny_bits(&state->other, mask); 683 deny_bits(&state->everyone, mask); 684 deny_bits_array(state->users, mask); 685 deny_bits_array(state->groups, mask); 686 } 687 } 688 } 689 690 static int nfs4_acl_nfsv4_to_posix(struct nfs4_acl *acl, 691 struct posix_acl **pacl, struct posix_acl **dpacl, 692 unsigned int flags) 693 { 694 struct posix_acl_state effective_acl_state, default_acl_state; 695 struct nfs4_ace *ace; 696 int ret; 697 698 ret = init_state(&effective_acl_state, acl->naces); 699 if (ret) 700 return ret; 701 ret = init_state(&default_acl_state, acl->naces); 702 if (ret) 703 goto out_estate; 704 ret = -EINVAL; 705 for (ace = acl->aces; ace < acl->aces + acl->naces; ace++) { 706 if (ace->type != NFS4_ACE_ACCESS_ALLOWED_ACE_TYPE && 707 ace->type != NFS4_ACE_ACCESS_DENIED_ACE_TYPE) 708 goto out_dstate; 709 if (ace->flag & ~NFS4_SUPPORTED_FLAGS) 710 goto out_dstate; 711 if ((ace->flag & NFS4_INHERITANCE_FLAGS) == 0) { 712 process_one_v4_ace(&effective_acl_state, ace); 713 continue; 714 } 715 if (!(flags & NFS4_ACL_DIR)) 716 goto out_dstate; 717 /* 718 * Note that when only one of FILE_INHERIT or DIRECTORY_INHERIT 719 * is set, we're effectively turning on the other. That's OK, 720 * according to rfc 3530. 721 */ 722 process_one_v4_ace(&default_acl_state, ace); 723 724 if (!(ace->flag & NFS4_ACE_INHERIT_ONLY_ACE)) 725 process_one_v4_ace(&effective_acl_state, ace); 726 } 727 *pacl = posix_state_to_acl(&effective_acl_state, flags); 728 if (IS_ERR(*pacl)) { 729 ret = PTR_ERR(*pacl); 730 *pacl = NULL; 731 goto out_dstate; 732 } 733 *dpacl = posix_state_to_acl(&default_acl_state, 734 flags | NFS4_ACL_TYPE_DEFAULT); 735 if (IS_ERR(*dpacl)) { 736 ret = PTR_ERR(*dpacl); 737 *dpacl = NULL; 738 posix_acl_release(*pacl); 739 *pacl = NULL; 740 goto out_dstate; 741 } 742 sort_pacl(*pacl); 743 sort_pacl(*dpacl); 744 ret = 0; 745 out_dstate: 746 free_state(&default_acl_state); 747 out_estate: 748 free_state(&effective_acl_state); 749 return ret; 750 } 751 752 __be32 753 nfsd4_set_nfs4_acl(struct svc_rqst *rqstp, struct svc_fh *fhp, 754 struct nfs4_acl *acl) 755 { 756 __be32 error; 757 int host_error; 758 struct dentry *dentry; 759 struct inode *inode; 760 struct posix_acl *pacl = NULL, *dpacl = NULL; 761 unsigned int flags = 0; 762 763 /* Get inode */ 764 error = fh_verify(rqstp, fhp, 0, NFSD_MAY_SATTR); 765 if (error) 766 return error; 767 768 dentry = fhp->fh_dentry; 769 inode = d_inode(dentry); 770 771 if (!inode->i_op->set_acl || !IS_POSIXACL(inode)) 772 return nfserr_attrnotsupp; 773 774 if (S_ISDIR(inode->i_mode)) 775 flags = NFS4_ACL_DIR; 776 777 host_error = nfs4_acl_nfsv4_to_posix(acl, &pacl, &dpacl, flags); 778 if (host_error == -EINVAL) 779 return nfserr_attrnotsupp; 780 if (host_error < 0) 781 goto out_nfserr; 782 783 host_error = inode->i_op->set_acl(inode, pacl, ACL_TYPE_ACCESS); 784 if (host_error < 0) 785 goto out_release; 786 787 if (S_ISDIR(inode->i_mode)) { 788 host_error = inode->i_op->set_acl(inode, dpacl, 789 ACL_TYPE_DEFAULT); 790 } 791 792 out_release: 793 posix_acl_release(pacl); 794 posix_acl_release(dpacl); 795 out_nfserr: 796 if (host_error == -EOPNOTSUPP) 797 return nfserr_attrnotsupp; 798 else 799 return nfserrno(host_error); 800 } 801 802 803 static short 804 ace2type(struct nfs4_ace *ace) 805 { 806 switch (ace->whotype) { 807 case NFS4_ACL_WHO_NAMED: 808 return (ace->flag & NFS4_ACE_IDENTIFIER_GROUP ? 809 ACL_GROUP : ACL_USER); 810 case NFS4_ACL_WHO_OWNER: 811 return ACL_USER_OBJ; 812 case NFS4_ACL_WHO_GROUP: 813 return ACL_GROUP_OBJ; 814 case NFS4_ACL_WHO_EVERYONE: 815 return ACL_OTHER; 816 } 817 BUG(); 818 return -1; 819 } 820 821 /* 822 * return the size of the struct nfs4_acl required to represent an acl 823 * with @entries entries. 824 */ 825 int nfs4_acl_bytes(int entries) 826 { 827 return sizeof(struct nfs4_acl) + entries * sizeof(struct nfs4_ace); 828 } 829 830 static struct { 831 char *string; 832 int stringlen; 833 int type; 834 } s2t_map[] = { 835 { 836 .string = "OWNER@", 837 .stringlen = sizeof("OWNER@") - 1, 838 .type = NFS4_ACL_WHO_OWNER, 839 }, 840 { 841 .string = "GROUP@", 842 .stringlen = sizeof("GROUP@") - 1, 843 .type = NFS4_ACL_WHO_GROUP, 844 }, 845 { 846 .string = "EVERYONE@", 847 .stringlen = sizeof("EVERYONE@") - 1, 848 .type = NFS4_ACL_WHO_EVERYONE, 849 }, 850 }; 851 852 int 853 nfs4_acl_get_whotype(char *p, u32 len) 854 { 855 int i; 856 857 for (i = 0; i < ARRAY_SIZE(s2t_map); i++) { 858 if (s2t_map[i].stringlen == len && 859 0 == memcmp(s2t_map[i].string, p, len)) 860 return s2t_map[i].type; 861 } 862 return NFS4_ACL_WHO_NAMED; 863 } 864 865 __be32 nfs4_acl_write_who(struct xdr_stream *xdr, int who) 866 { 867 __be32 *p; 868 int i; 869 870 for (i = 0; i < ARRAY_SIZE(s2t_map); i++) { 871 if (s2t_map[i].type != who) 872 continue; 873 p = xdr_reserve_space(xdr, s2t_map[i].stringlen + 4); 874 if (!p) 875 return nfserr_resource; 876 p = xdr_encode_opaque(p, s2t_map[i].string, 877 s2t_map[i].stringlen); 878 return 0; 879 } 880 WARN_ON_ONCE(1); 881 return nfserr_serverfault; 882 } 883