1 /* 2 * fs/nfs4acl/acl.c 3 * 4 * Common NFSv4 ACL handling code. 5 * 6 * Copyright (c) 2002, 2003 The Regents of the University of Michigan. 7 * All rights reserved. 8 * 9 * Marius Aamodt Eriksen <marius@umich.edu> 10 * Jeff Sedlak <jsedlak@umich.edu> 11 * J. Bruce Fields <bfields@umich.edu> 12 * 13 * Redistribution and use in source and binary forms, with or without 14 * modification, are permitted provided that the following conditions 15 * are met: 16 * 17 * 1. Redistributions of source code must retain the above copyright 18 * notice, this list of conditions and the following disclaimer. 19 * 2. Redistributions in binary form must reproduce the above copyright 20 * notice, this list of conditions and the following disclaimer in the 21 * documentation and/or other materials provided with the distribution. 22 * 3. Neither the name of the University nor the names of its 23 * contributors may be used to endorse or promote products derived 24 * from this software without specific prior written permission. 25 * 26 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED 27 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 28 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE 29 * DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 30 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 31 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 32 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR 33 * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF 34 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING 35 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS 36 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 37 */ 38 39 #include <linux/string.h> 40 #include <linux/slab.h> 41 #include <linux/list.h> 42 #include <linux/types.h> 43 #include <linux/fs.h> 44 #include <linux/module.h> 45 #include <linux/nfs_fs.h> 46 #include <linux/posix_acl.h> 47 #include <linux/nfs4.h> 48 #include <linux/nfs4_acl.h> 49 50 51 /* mode bit translations: */ 52 #define NFS4_READ_MODE (NFS4_ACE_READ_DATA) 53 #define NFS4_WRITE_MODE (NFS4_ACE_WRITE_DATA | NFS4_ACE_APPEND_DATA) 54 #define NFS4_EXECUTE_MODE NFS4_ACE_EXECUTE 55 #define NFS4_ANYONE_MODE (NFS4_ACE_READ_ATTRIBUTES | NFS4_ACE_READ_ACL | NFS4_ACE_SYNCHRONIZE) 56 #define NFS4_OWNER_MODE (NFS4_ACE_WRITE_ATTRIBUTES | NFS4_ACE_WRITE_ACL) 57 58 /* We don't support these bits; insist they be neither allowed nor denied */ 59 #define NFS4_MASK_UNSUPP (NFS4_ACE_DELETE | NFS4_ACE_WRITE_OWNER \ 60 | NFS4_ACE_READ_NAMED_ATTRS | NFS4_ACE_WRITE_NAMED_ATTRS) 61 62 /* flags used to simulate posix default ACLs */ 63 #define NFS4_INHERITANCE_FLAGS (NFS4_ACE_FILE_INHERIT_ACE \ 64 | NFS4_ACE_DIRECTORY_INHERIT_ACE) 65 66 #define NFS4_SUPPORTED_FLAGS (NFS4_INHERITANCE_FLAGS \ 67 | NFS4_ACE_INHERIT_ONLY_ACE \ 68 | NFS4_ACE_IDENTIFIER_GROUP) 69 70 #define MASK_EQUAL(mask1, mask2) \ 71 ( ((mask1) & NFS4_ACE_MASK_ALL) == ((mask2) & NFS4_ACE_MASK_ALL) ) 72 73 static u32 74 mask_from_posix(unsigned short perm, unsigned int flags) 75 { 76 int mask = NFS4_ANYONE_MODE; 77 78 if (flags & NFS4_ACL_OWNER) 79 mask |= NFS4_OWNER_MODE; 80 if (perm & ACL_READ) 81 mask |= NFS4_READ_MODE; 82 if (perm & ACL_WRITE) 83 mask |= NFS4_WRITE_MODE; 84 if ((perm & ACL_WRITE) && (flags & NFS4_ACL_DIR)) 85 mask |= NFS4_ACE_DELETE_CHILD; 86 if (perm & ACL_EXECUTE) 87 mask |= NFS4_EXECUTE_MODE; 88 return mask; 89 } 90 91 static u32 92 deny_mask_from_posix(unsigned short perm, u32 flags) 93 { 94 u32 mask = 0; 95 96 if (perm & ACL_READ) 97 mask |= NFS4_READ_MODE; 98 if (perm & ACL_WRITE) 99 mask |= NFS4_WRITE_MODE; 100 if ((perm & ACL_WRITE) && (flags & NFS4_ACL_DIR)) 101 mask |= NFS4_ACE_DELETE_CHILD; 102 if (perm & ACL_EXECUTE) 103 mask |= NFS4_EXECUTE_MODE; 104 return mask; 105 } 106 107 /* XXX: modify functions to return NFS errors; they're only ever 108 * used by nfs code, after all.... */ 109 110 /* We only map from NFSv4 to POSIX ACLs when setting ACLs, when we err on the 111 * side of being more restrictive, so the mode bit mapping below is 112 * pessimistic. An optimistic version would be needed to handle DENY's, 113 * but we espect to coalesce all ALLOWs and DENYs before mapping to mode 114 * bits. */ 115 116 static void 117 low_mode_from_nfs4(u32 perm, unsigned short *mode, unsigned int flags) 118 { 119 u32 write_mode = NFS4_WRITE_MODE; 120 121 if (flags & NFS4_ACL_DIR) 122 write_mode |= NFS4_ACE_DELETE_CHILD; 123 *mode = 0; 124 if ((perm & NFS4_READ_MODE) == NFS4_READ_MODE) 125 *mode |= ACL_READ; 126 if ((perm & write_mode) == write_mode) 127 *mode |= ACL_WRITE; 128 if ((perm & NFS4_EXECUTE_MODE) == NFS4_EXECUTE_MODE) 129 *mode |= ACL_EXECUTE; 130 } 131 132 struct ace_container { 133 struct nfs4_ace *ace; 134 struct list_head ace_l; 135 }; 136 137 static short ace2type(struct nfs4_ace *); 138 static void _posix_to_nfsv4_one(struct posix_acl *, struct nfs4_acl *, 139 unsigned int); 140 141 struct nfs4_acl * 142 nfs4_acl_posix_to_nfsv4(struct posix_acl *pacl, struct posix_acl *dpacl, 143 unsigned int flags) 144 { 145 struct nfs4_acl *acl; 146 int size = 0; 147 148 if (pacl) { 149 if (posix_acl_valid(pacl) < 0) 150 return ERR_PTR(-EINVAL); 151 size += 2*pacl->a_count; 152 } 153 if (dpacl) { 154 if (posix_acl_valid(dpacl) < 0) 155 return ERR_PTR(-EINVAL); 156 size += 2*dpacl->a_count; 157 } 158 159 /* Allocate for worst case: one (deny, allow) pair each: */ 160 acl = nfs4_acl_new(size); 161 if (acl == NULL) 162 return ERR_PTR(-ENOMEM); 163 164 if (pacl) 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 return acl; 171 } 172 173 struct posix_acl_summary { 174 unsigned short owner; 175 unsigned short users; 176 unsigned short group; 177 unsigned short groups; 178 unsigned short other; 179 unsigned short mask; 180 }; 181 182 static void 183 summarize_posix_acl(struct posix_acl *acl, struct posix_acl_summary *pas) 184 { 185 struct posix_acl_entry *pa, *pe; 186 187 /* 188 * Only pas.users and pas.groups need initialization; previous 189 * posix_acl_valid() calls ensure that the other fields will be 190 * initialized in the following loop. But, just to placate gcc: 191 */ 192 memset(pas, 0, sizeof(*pas)); 193 pas->mask = 07; 194 195 pe = acl->a_entries + acl->a_count; 196 197 FOREACH_ACL_ENTRY(pa, acl, pe) { 198 switch (pa->e_tag) { 199 case ACL_USER_OBJ: 200 pas->owner = pa->e_perm; 201 break; 202 case ACL_GROUP_OBJ: 203 pas->group = pa->e_perm; 204 break; 205 case ACL_USER: 206 pas->users |= pa->e_perm; 207 break; 208 case ACL_GROUP: 209 pas->groups |= pa->e_perm; 210 break; 211 case ACL_OTHER: 212 pas->other = pa->e_perm; 213 break; 214 case ACL_MASK: 215 pas->mask = pa->e_perm; 216 break; 217 } 218 } 219 /* We'll only care about effective permissions: */ 220 pas->users &= pas->mask; 221 pas->group &= pas->mask; 222 pas->groups &= pas->mask; 223 } 224 225 /* We assume the acl has been verified with posix_acl_valid. */ 226 static void 227 _posix_to_nfsv4_one(struct posix_acl *pacl, struct nfs4_acl *acl, 228 unsigned int flags) 229 { 230 struct posix_acl_entry *pa, *group_owner_entry; 231 struct nfs4_ace *ace; 232 struct posix_acl_summary pas; 233 unsigned short deny; 234 int eflag = ((flags & NFS4_ACL_TYPE_DEFAULT) ? 235 NFS4_INHERITANCE_FLAGS | NFS4_ACE_INHERIT_ONLY_ACE : 0); 236 237 BUG_ON(pacl->a_count < 3); 238 summarize_posix_acl(pacl, &pas); 239 240 pa = pacl->a_entries; 241 ace = acl->aces + acl->naces; 242 243 /* We could deny everything not granted by the owner: */ 244 deny = ~pas.owner; 245 /* 246 * but it is equivalent (and simpler) to deny only what is not 247 * granted by later entries: 248 */ 249 deny &= pas.users | pas.group | pas.groups | pas.other; 250 if (deny) { 251 ace->type = NFS4_ACE_ACCESS_DENIED_ACE_TYPE; 252 ace->flag = eflag; 253 ace->access_mask = deny_mask_from_posix(deny, flags); 254 ace->whotype = NFS4_ACL_WHO_OWNER; 255 ace++; 256 acl->naces++; 257 } 258 259 ace->type = NFS4_ACE_ACCESS_ALLOWED_ACE_TYPE; 260 ace->flag = eflag; 261 ace->access_mask = mask_from_posix(pa->e_perm, flags | NFS4_ACL_OWNER); 262 ace->whotype = NFS4_ACL_WHO_OWNER; 263 ace++; 264 acl->naces++; 265 pa++; 266 267 while (pa->e_tag == ACL_USER) { 268 deny = ~(pa->e_perm & pas.mask); 269 deny &= pas.groups | pas.group | pas.other; 270 if (deny) { 271 ace->type = NFS4_ACE_ACCESS_DENIED_ACE_TYPE; 272 ace->flag = eflag; 273 ace->access_mask = deny_mask_from_posix(deny, flags); 274 ace->whotype = NFS4_ACL_WHO_NAMED; 275 ace->who = pa->e_id; 276 ace++; 277 acl->naces++; 278 } 279 ace->type = NFS4_ACE_ACCESS_ALLOWED_ACE_TYPE; 280 ace->flag = eflag; 281 ace->access_mask = mask_from_posix(pa->e_perm & pas.mask, 282 flags); 283 ace->whotype = NFS4_ACL_WHO_NAMED; 284 ace->who = pa->e_id; 285 ace++; 286 acl->naces++; 287 pa++; 288 } 289 290 /* In the case of groups, we apply allow ACEs first, then deny ACEs, 291 * since a user can be in more than one group. */ 292 293 /* allow ACEs */ 294 295 group_owner_entry = pa; 296 297 ace->type = NFS4_ACE_ACCESS_ALLOWED_ACE_TYPE; 298 ace->flag = eflag; 299 ace->access_mask = mask_from_posix(pas.group, flags); 300 ace->whotype = NFS4_ACL_WHO_GROUP; 301 ace++; 302 acl->naces++; 303 pa++; 304 305 while (pa->e_tag == ACL_GROUP) { 306 ace->type = NFS4_ACE_ACCESS_ALLOWED_ACE_TYPE; 307 ace->flag = eflag | NFS4_ACE_IDENTIFIER_GROUP; 308 ace->access_mask = mask_from_posix(pa->e_perm & pas.mask, 309 flags); 310 ace->whotype = NFS4_ACL_WHO_NAMED; 311 ace->who = pa->e_id; 312 ace++; 313 acl->naces++; 314 pa++; 315 } 316 317 /* deny ACEs */ 318 319 pa = group_owner_entry; 320 321 deny = ~pas.group & pas.other; 322 if (deny) { 323 ace->type = NFS4_ACE_ACCESS_DENIED_ACE_TYPE; 324 ace->flag = eflag | NFS4_ACE_IDENTIFIER_GROUP; 325 ace->access_mask = deny_mask_from_posix(deny, flags); 326 ace->whotype = NFS4_ACL_WHO_GROUP; 327 ace++; 328 acl->naces++; 329 } 330 pa++; 331 332 while (pa->e_tag == ACL_GROUP) { 333 deny = ~(pa->e_perm & pas.mask); 334 deny &= pas.other; 335 if (deny) { 336 ace->type = NFS4_ACE_ACCESS_DENIED_ACE_TYPE; 337 ace->flag = eflag | NFS4_ACE_IDENTIFIER_GROUP; 338 ace->access_mask = mask_from_posix(deny, flags); 339 ace->whotype = NFS4_ACL_WHO_NAMED; 340 ace->who = pa->e_id; 341 ace++; 342 acl->naces++; 343 } 344 pa++; 345 } 346 347 if (pa->e_tag == ACL_MASK) 348 pa++; 349 ace->type = NFS4_ACE_ACCESS_ALLOWED_ACE_TYPE; 350 ace->flag = eflag; 351 ace->access_mask = mask_from_posix(pa->e_perm, flags); 352 ace->whotype = NFS4_ACL_WHO_EVERYONE; 353 acl->naces++; 354 } 355 356 static void 357 sort_pacl_range(struct posix_acl *pacl, int start, int end) { 358 int sorted = 0, i; 359 struct posix_acl_entry tmp; 360 361 /* We just do a bubble sort; easy to do in place, and we're not 362 * expecting acl's to be long enough to justify anything more. */ 363 while (!sorted) { 364 sorted = 1; 365 for (i = start; i < end; i++) { 366 if (pacl->a_entries[i].e_id 367 > pacl->a_entries[i+1].e_id) { 368 sorted = 0; 369 tmp = pacl->a_entries[i]; 370 pacl->a_entries[i] = pacl->a_entries[i+1]; 371 pacl->a_entries[i+1] = tmp; 372 } 373 } 374 } 375 } 376 377 static void 378 sort_pacl(struct posix_acl *pacl) 379 { 380 /* posix_acl_valid requires that users and groups be in order 381 * by uid/gid. */ 382 int i, j; 383 384 if (pacl->a_count <= 4) 385 return; /* no users or groups */ 386 i = 1; 387 while (pacl->a_entries[i].e_tag == ACL_USER) 388 i++; 389 sort_pacl_range(pacl, 1, i-1); 390 391 BUG_ON(pacl->a_entries[i].e_tag != ACL_GROUP_OBJ); 392 j = i++; 393 while (pacl->a_entries[j].e_tag == ACL_GROUP) 394 j++; 395 sort_pacl_range(pacl, i, j-1); 396 return; 397 } 398 399 /* 400 * While processing the NFSv4 ACE, this maintains bitmasks representing 401 * which permission bits have been allowed and which denied to a given 402 * entity: */ 403 struct posix_ace_state { 404 u32 allow; 405 u32 deny; 406 }; 407 408 struct posix_user_ace_state { 409 uid_t uid; 410 struct posix_ace_state perms; 411 }; 412 413 struct posix_ace_state_array { 414 int n; 415 struct posix_user_ace_state aces[]; 416 }; 417 418 /* 419 * While processing the NFSv4 ACE, this maintains the partial permissions 420 * calculated so far: */ 421 422 struct posix_acl_state { 423 int empty; 424 struct posix_ace_state owner; 425 struct posix_ace_state group; 426 struct posix_ace_state other; 427 struct posix_ace_state everyone; 428 struct posix_ace_state mask; /* Deny unused in this case */ 429 struct posix_ace_state_array *users; 430 struct posix_ace_state_array *groups; 431 }; 432 433 static int 434 init_state(struct posix_acl_state *state, int cnt) 435 { 436 int alloc; 437 438 memset(state, 0, sizeof(struct posix_acl_state)); 439 state->empty = 1; 440 /* 441 * In the worst case, each individual acl could be for a distinct 442 * named user or group, but we don't no which, so we allocate 443 * enough space for either: 444 */ 445 alloc = sizeof(struct posix_ace_state_array) 446 + cnt*sizeof(struct posix_ace_state); 447 state->users = kzalloc(alloc, GFP_KERNEL); 448 if (!state->users) 449 return -ENOMEM; 450 state->groups = kzalloc(alloc, GFP_KERNEL); 451 if (!state->groups) { 452 kfree(state->users); 453 return -ENOMEM; 454 } 455 return 0; 456 } 457 458 static void 459 free_state(struct posix_acl_state *state) { 460 kfree(state->users); 461 kfree(state->groups); 462 } 463 464 static inline void add_to_mask(struct posix_acl_state *state, struct posix_ace_state *astate) 465 { 466 state->mask.allow |= astate->allow; 467 } 468 469 /* 470 * Certain bits (SYNCHRONIZE, DELETE, WRITE_OWNER, READ/WRITE_NAMED_ATTRS, 471 * READ_ATTRIBUTES, READ_ACL) are currently unenforceable and don't translate 472 * to traditional read/write/execute permissions. 473 * 474 * It's problematic to reject acls that use certain mode bits, because it 475 * places the burden on users to learn the rules about which bits one 476 * particular server sets, without giving the user a lot of help--we return an 477 * error that could mean any number of different things. To make matters 478 * worse, the problematic bits might be introduced by some application that's 479 * automatically mapping from some other acl model. 480 * 481 * So wherever possible we accept anything, possibly erring on the side of 482 * denying more permissions than necessary. 483 * 484 * However we do reject *explicit* DENY's of a few bits representing 485 * permissions we could never deny: 486 */ 487 488 static inline int check_deny(u32 mask, int isowner) 489 { 490 if (mask & (NFS4_ACE_READ_ATTRIBUTES | NFS4_ACE_READ_ACL)) 491 return -EINVAL; 492 if (!isowner) 493 return 0; 494 if (mask & (NFS4_ACE_WRITE_ATTRIBUTES | NFS4_ACE_WRITE_ACL)) 495 return -EINVAL; 496 return 0; 497 } 498 499 static struct posix_acl * 500 posix_state_to_acl(struct posix_acl_state *state, unsigned int flags) 501 { 502 struct posix_acl_entry *pace; 503 struct posix_acl *pacl; 504 int nace; 505 int i, error = 0; 506 507 /* 508 * ACLs with no ACEs are treated differently in the inheritable 509 * and effective cases: when there are no inheritable ACEs, we 510 * set a zero-length default posix acl: 511 */ 512 if (state->empty && (flags & NFS4_ACL_TYPE_DEFAULT)) { 513 pacl = posix_acl_alloc(0, GFP_KERNEL); 514 return pacl ? pacl : ERR_PTR(-ENOMEM); 515 } 516 /* 517 * When there are no effective ACEs, the following will end 518 * up setting a 3-element effective posix ACL with all 519 * permissions zero. 520 */ 521 nace = 4 + state->users->n + state->groups->n; 522 pacl = posix_acl_alloc(nace, GFP_KERNEL); 523 if (!pacl) 524 return ERR_PTR(-ENOMEM); 525 526 pace = pacl->a_entries; 527 pace->e_tag = ACL_USER_OBJ; 528 error = check_deny(state->owner.deny, 1); 529 if (error) 530 goto out_err; 531 low_mode_from_nfs4(state->owner.allow, &pace->e_perm, flags); 532 pace->e_id = ACL_UNDEFINED_ID; 533 534 for (i=0; i < state->users->n; i++) { 535 pace++; 536 pace->e_tag = ACL_USER; 537 error = check_deny(state->users->aces[i].perms.deny, 0); 538 if (error) 539 goto out_err; 540 low_mode_from_nfs4(state->users->aces[i].perms.allow, 541 &pace->e_perm, flags); 542 pace->e_id = state->users->aces[i].uid; 543 add_to_mask(state, &state->users->aces[i].perms); 544 } 545 546 pace++; 547 pace->e_tag = ACL_GROUP_OBJ; 548 error = check_deny(state->group.deny, 0); 549 if (error) 550 goto out_err; 551 low_mode_from_nfs4(state->group.allow, &pace->e_perm, flags); 552 pace->e_id = ACL_UNDEFINED_ID; 553 add_to_mask(state, &state->group); 554 555 for (i=0; i < state->groups->n; i++) { 556 pace++; 557 pace->e_tag = ACL_GROUP; 558 error = check_deny(state->groups->aces[i].perms.deny, 0); 559 if (error) 560 goto out_err; 561 low_mode_from_nfs4(state->groups->aces[i].perms.allow, 562 &pace->e_perm, flags); 563 pace->e_id = state->groups->aces[i].uid; 564 add_to_mask(state, &state->groups->aces[i].perms); 565 } 566 567 pace++; 568 pace->e_tag = ACL_MASK; 569 low_mode_from_nfs4(state->mask.allow, &pace->e_perm, flags); 570 pace->e_id = ACL_UNDEFINED_ID; 571 572 pace++; 573 pace->e_tag = ACL_OTHER; 574 error = check_deny(state->other.deny, 0); 575 if (error) 576 goto out_err; 577 low_mode_from_nfs4(state->other.allow, &pace->e_perm, flags); 578 pace->e_id = ACL_UNDEFINED_ID; 579 580 return pacl; 581 out_err: 582 posix_acl_release(pacl); 583 return ERR_PTR(error); 584 } 585 586 static inline void allow_bits(struct posix_ace_state *astate, u32 mask) 587 { 588 /* Allow all bits in the mask not already denied: */ 589 astate->allow |= mask & ~astate->deny; 590 } 591 592 static inline void deny_bits(struct posix_ace_state *astate, u32 mask) 593 { 594 /* Deny all bits in the mask not already allowed: */ 595 astate->deny |= mask & ~astate->allow; 596 } 597 598 static int find_uid(struct posix_acl_state *state, struct posix_ace_state_array *a, uid_t uid) 599 { 600 int i; 601 602 for (i = 0; i < a->n; i++) 603 if (a->aces[i].uid == uid) 604 return i; 605 /* Not found: */ 606 a->n++; 607 a->aces[i].uid = uid; 608 a->aces[i].perms.allow = state->everyone.allow; 609 a->aces[i].perms.deny = state->everyone.deny; 610 611 return i; 612 } 613 614 static void deny_bits_array(struct posix_ace_state_array *a, u32 mask) 615 { 616 int i; 617 618 for (i=0; i < a->n; i++) 619 deny_bits(&a->aces[i].perms, mask); 620 } 621 622 static void allow_bits_array(struct posix_ace_state_array *a, u32 mask) 623 { 624 int i; 625 626 for (i=0; i < a->n; i++) 627 allow_bits(&a->aces[i].perms, mask); 628 } 629 630 static void process_one_v4_ace(struct posix_acl_state *state, 631 struct nfs4_ace *ace) 632 { 633 u32 mask = ace->access_mask; 634 int i; 635 636 state->empty = 0; 637 638 switch (ace2type(ace)) { 639 case ACL_USER_OBJ: 640 if (ace->type == NFS4_ACE_ACCESS_ALLOWED_ACE_TYPE) { 641 allow_bits(&state->owner, mask); 642 } else { 643 deny_bits(&state->owner, mask); 644 } 645 break; 646 case ACL_USER: 647 i = find_uid(state, state->users, ace->who); 648 if (ace->type == NFS4_ACE_ACCESS_ALLOWED_ACE_TYPE) { 649 allow_bits(&state->users->aces[i].perms, mask); 650 } else { 651 deny_bits(&state->users->aces[i].perms, mask); 652 mask = state->users->aces[i].perms.deny; 653 deny_bits(&state->owner, mask); 654 } 655 break; 656 case ACL_GROUP_OBJ: 657 if (ace->type == NFS4_ACE_ACCESS_ALLOWED_ACE_TYPE) { 658 allow_bits(&state->group, mask); 659 } else { 660 deny_bits(&state->group, mask); 661 mask = state->group.deny; 662 deny_bits(&state->owner, mask); 663 deny_bits(&state->everyone, mask); 664 deny_bits_array(state->users, mask); 665 deny_bits_array(state->groups, mask); 666 } 667 break; 668 case ACL_GROUP: 669 i = find_uid(state, state->groups, ace->who); 670 if (ace->type == NFS4_ACE_ACCESS_ALLOWED_ACE_TYPE) { 671 allow_bits(&state->groups->aces[i].perms, mask); 672 } else { 673 deny_bits(&state->groups->aces[i].perms, mask); 674 mask = state->groups->aces[i].perms.deny; 675 deny_bits(&state->owner, mask); 676 deny_bits(&state->group, mask); 677 deny_bits(&state->everyone, mask); 678 deny_bits_array(state->users, mask); 679 deny_bits_array(state->groups, mask); 680 } 681 break; 682 case ACL_OTHER: 683 if (ace->type == NFS4_ACE_ACCESS_ALLOWED_ACE_TYPE) { 684 allow_bits(&state->owner, mask); 685 allow_bits(&state->group, mask); 686 allow_bits(&state->other, mask); 687 allow_bits(&state->everyone, mask); 688 allow_bits_array(state->users, mask); 689 allow_bits_array(state->groups, mask); 690 } else { 691 deny_bits(&state->owner, mask); 692 deny_bits(&state->group, mask); 693 deny_bits(&state->other, mask); 694 deny_bits(&state->everyone, mask); 695 deny_bits_array(state->users, mask); 696 deny_bits_array(state->groups, mask); 697 } 698 } 699 } 700 701 int nfs4_acl_nfsv4_to_posix(struct nfs4_acl *acl, struct posix_acl **pacl, 702 struct posix_acl **dpacl, unsigned int flags) 703 { 704 struct posix_acl_state effective_acl_state, default_acl_state; 705 struct nfs4_ace *ace; 706 int ret; 707 708 ret = init_state(&effective_acl_state, acl->naces); 709 if (ret) 710 return ret; 711 ret = init_state(&default_acl_state, acl->naces); 712 if (ret) 713 goto out_estate; 714 ret = -EINVAL; 715 for (ace = acl->aces; ace < acl->aces + acl->naces; ace++) { 716 if (ace->type != NFS4_ACE_ACCESS_ALLOWED_ACE_TYPE && 717 ace->type != NFS4_ACE_ACCESS_DENIED_ACE_TYPE) 718 goto out_dstate; 719 if (ace->flag & ~NFS4_SUPPORTED_FLAGS) 720 goto out_dstate; 721 if ((ace->flag & NFS4_INHERITANCE_FLAGS) == 0) { 722 process_one_v4_ace(&effective_acl_state, ace); 723 continue; 724 } 725 if (!(flags & NFS4_ACL_DIR)) 726 goto out_dstate; 727 /* 728 * Note that when only one of FILE_INHERIT or DIRECTORY_INHERIT 729 * is set, we're effectively turning on the other. That's OK, 730 * according to rfc 3530. 731 */ 732 process_one_v4_ace(&default_acl_state, ace); 733 734 if (!(ace->flag & NFS4_ACE_INHERIT_ONLY_ACE)) 735 process_one_v4_ace(&effective_acl_state, ace); 736 } 737 *pacl = posix_state_to_acl(&effective_acl_state, flags); 738 if (IS_ERR(*pacl)) { 739 ret = PTR_ERR(*pacl); 740 *pacl = NULL; 741 goto out_dstate; 742 } 743 *dpacl = posix_state_to_acl(&default_acl_state, 744 flags | NFS4_ACL_TYPE_DEFAULT); 745 if (IS_ERR(*dpacl)) { 746 ret = PTR_ERR(*dpacl); 747 *dpacl = NULL; 748 posix_acl_release(*pacl); 749 *pacl = NULL; 750 goto out_dstate; 751 } 752 sort_pacl(*pacl); 753 sort_pacl(*dpacl); 754 ret = 0; 755 out_dstate: 756 free_state(&default_acl_state); 757 out_estate: 758 free_state(&effective_acl_state); 759 return ret; 760 } 761 762 static short 763 ace2type(struct nfs4_ace *ace) 764 { 765 switch (ace->whotype) { 766 case NFS4_ACL_WHO_NAMED: 767 return (ace->flag & NFS4_ACE_IDENTIFIER_GROUP ? 768 ACL_GROUP : ACL_USER); 769 case NFS4_ACL_WHO_OWNER: 770 return ACL_USER_OBJ; 771 case NFS4_ACL_WHO_GROUP: 772 return ACL_GROUP_OBJ; 773 case NFS4_ACL_WHO_EVERYONE: 774 return ACL_OTHER; 775 } 776 BUG(); 777 return -1; 778 } 779 780 EXPORT_SYMBOL(nfs4_acl_posix_to_nfsv4); 781 EXPORT_SYMBOL(nfs4_acl_nfsv4_to_posix); 782 783 struct nfs4_acl * 784 nfs4_acl_new(int n) 785 { 786 struct nfs4_acl *acl; 787 788 acl = kmalloc(sizeof(*acl) + n*sizeof(struct nfs4_ace), GFP_KERNEL); 789 if (acl == NULL) 790 return NULL; 791 acl->naces = 0; 792 return acl; 793 } 794 795 static struct { 796 char *string; 797 int stringlen; 798 int type; 799 } s2t_map[] = { 800 { 801 .string = "OWNER@", 802 .stringlen = sizeof("OWNER@") - 1, 803 .type = NFS4_ACL_WHO_OWNER, 804 }, 805 { 806 .string = "GROUP@", 807 .stringlen = sizeof("GROUP@") - 1, 808 .type = NFS4_ACL_WHO_GROUP, 809 }, 810 { 811 .string = "EVERYONE@", 812 .stringlen = sizeof("EVERYONE@") - 1, 813 .type = NFS4_ACL_WHO_EVERYONE, 814 }, 815 }; 816 817 int 818 nfs4_acl_get_whotype(char *p, u32 len) 819 { 820 int i; 821 822 for (i = 0; i < ARRAY_SIZE(s2t_map); i++) { 823 if (s2t_map[i].stringlen == len && 824 0 == memcmp(s2t_map[i].string, p, len)) 825 return s2t_map[i].type; 826 } 827 return NFS4_ACL_WHO_NAMED; 828 } 829 830 int 831 nfs4_acl_write_who(int who, char *p) 832 { 833 int i; 834 835 for (i = 0; i < ARRAY_SIZE(s2t_map); i++) { 836 if (s2t_map[i].type == who) { 837 memcpy(p, s2t_map[i].string, s2t_map[i].stringlen); 838 return s2t_map[i].stringlen; 839 } 840 } 841 BUG(); 842 return -1; 843 } 844 845 EXPORT_SYMBOL(nfs4_acl_new); 846 EXPORT_SYMBOL(nfs4_acl_get_whotype); 847 EXPORT_SYMBOL(nfs4_acl_write_who); 848