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 <linux/export.h> 40 #include "acl.h" 41 42 43 /* mode bit translations: */ 44 #define NFS4_READ_MODE (NFS4_ACE_READ_DATA) 45 #define NFS4_WRITE_MODE (NFS4_ACE_WRITE_DATA | NFS4_ACE_APPEND_DATA) 46 #define NFS4_EXECUTE_MODE NFS4_ACE_EXECUTE 47 #define NFS4_ANYONE_MODE (NFS4_ACE_READ_ATTRIBUTES | NFS4_ACE_READ_ACL | NFS4_ACE_SYNCHRONIZE) 48 #define NFS4_OWNER_MODE (NFS4_ACE_WRITE_ATTRIBUTES | NFS4_ACE_WRITE_ACL) 49 50 /* We don't support these bits; insist they be neither allowed nor denied */ 51 #define NFS4_MASK_UNSUPP (NFS4_ACE_DELETE | NFS4_ACE_WRITE_OWNER \ 52 | NFS4_ACE_READ_NAMED_ATTRS | NFS4_ACE_WRITE_NAMED_ATTRS) 53 54 /* flags used to simulate posix default ACLs */ 55 #define NFS4_INHERITANCE_FLAGS (NFS4_ACE_FILE_INHERIT_ACE \ 56 | NFS4_ACE_DIRECTORY_INHERIT_ACE) 57 58 #define NFS4_SUPPORTED_FLAGS (NFS4_INHERITANCE_FLAGS \ 59 | NFS4_ACE_INHERIT_ONLY_ACE \ 60 | NFS4_ACE_IDENTIFIER_GROUP) 61 62 #define MASK_EQUAL(mask1, mask2) \ 63 ( ((mask1) & NFS4_ACE_MASK_ALL) == ((mask2) & NFS4_ACE_MASK_ALL) ) 64 65 static u32 66 mask_from_posix(unsigned short perm, unsigned int flags) 67 { 68 int mask = NFS4_ANYONE_MODE; 69 70 if (flags & NFS4_ACL_OWNER) 71 mask |= NFS4_OWNER_MODE; 72 if (perm & ACL_READ) 73 mask |= NFS4_READ_MODE; 74 if (perm & ACL_WRITE) 75 mask |= NFS4_WRITE_MODE; 76 if ((perm & ACL_WRITE) && (flags & NFS4_ACL_DIR)) 77 mask |= NFS4_ACE_DELETE_CHILD; 78 if (perm & ACL_EXECUTE) 79 mask |= NFS4_EXECUTE_MODE; 80 return mask; 81 } 82 83 static u32 84 deny_mask_from_posix(unsigned short perm, u32 flags) 85 { 86 u32 mask = 0; 87 88 if (perm & ACL_READ) 89 mask |= NFS4_READ_MODE; 90 if (perm & ACL_WRITE) 91 mask |= NFS4_WRITE_MODE; 92 if ((perm & ACL_WRITE) && (flags & NFS4_ACL_DIR)) 93 mask |= NFS4_ACE_DELETE_CHILD; 94 if (perm & ACL_EXECUTE) 95 mask |= NFS4_EXECUTE_MODE; 96 return mask; 97 } 98 99 /* XXX: modify functions to return NFS errors; they're only ever 100 * used by nfs code, after all.... */ 101 102 /* We only map from NFSv4 to POSIX ACLs when setting ACLs, when we err on the 103 * side of being more restrictive, so the mode bit mapping below is 104 * pessimistic. An optimistic version would be needed to handle DENY's, 105 * but we espect to coalesce all ALLOWs and DENYs before mapping to mode 106 * bits. */ 107 108 static void 109 low_mode_from_nfs4(u32 perm, unsigned short *mode, unsigned int flags) 110 { 111 u32 write_mode = NFS4_WRITE_MODE; 112 113 if (flags & NFS4_ACL_DIR) 114 write_mode |= NFS4_ACE_DELETE_CHILD; 115 *mode = 0; 116 if ((perm & NFS4_READ_MODE) == NFS4_READ_MODE) 117 *mode |= ACL_READ; 118 if ((perm & write_mode) == write_mode) 119 *mode |= ACL_WRITE; 120 if ((perm & NFS4_EXECUTE_MODE) == NFS4_EXECUTE_MODE) 121 *mode |= ACL_EXECUTE; 122 } 123 124 struct ace_container { 125 struct nfs4_ace *ace; 126 struct list_head ace_l; 127 }; 128 129 static short ace2type(struct nfs4_ace *); 130 static void _posix_to_nfsv4_one(struct posix_acl *, struct nfs4_acl *, 131 unsigned int); 132 133 struct nfs4_acl * 134 nfs4_acl_posix_to_nfsv4(struct posix_acl *pacl, struct posix_acl *dpacl, 135 unsigned int flags) 136 { 137 struct nfs4_acl *acl; 138 int size = 0; 139 140 if (pacl) { 141 if (posix_acl_valid(pacl) < 0) 142 return ERR_PTR(-EINVAL); 143 size += 2*pacl->a_count; 144 } 145 if (dpacl) { 146 if (posix_acl_valid(dpacl) < 0) 147 return ERR_PTR(-EINVAL); 148 size += 2*dpacl->a_count; 149 } 150 151 /* Allocate for worst case: one (deny, allow) pair each: */ 152 acl = nfs4_acl_new(size); 153 if (acl == NULL) 154 return ERR_PTR(-ENOMEM); 155 156 if (pacl) 157 _posix_to_nfsv4_one(pacl, acl, flags & ~NFS4_ACL_TYPE_DEFAULT); 158 159 if (dpacl) 160 _posix_to_nfsv4_one(dpacl, acl, flags | NFS4_ACL_TYPE_DEFAULT); 161 162 return acl; 163 } 164 165 struct posix_acl_summary { 166 unsigned short owner; 167 unsigned short users; 168 unsigned short group; 169 unsigned short groups; 170 unsigned short other; 171 unsigned short mask; 172 }; 173 174 static void 175 summarize_posix_acl(struct posix_acl *acl, struct posix_acl_summary *pas) 176 { 177 struct posix_acl_entry *pa, *pe; 178 179 /* 180 * Only pas.users and pas.groups need initialization; previous 181 * posix_acl_valid() calls ensure that the other fields will be 182 * initialized in the following loop. But, just to placate gcc: 183 */ 184 memset(pas, 0, sizeof(*pas)); 185 pas->mask = 07; 186 187 pe = acl->a_entries + acl->a_count; 188 189 FOREACH_ACL_ENTRY(pa, acl, pe) { 190 switch (pa->e_tag) { 191 case ACL_USER_OBJ: 192 pas->owner = pa->e_perm; 193 break; 194 case ACL_GROUP_OBJ: 195 pas->group = pa->e_perm; 196 break; 197 case ACL_USER: 198 pas->users |= pa->e_perm; 199 break; 200 case ACL_GROUP: 201 pas->groups |= pa->e_perm; 202 break; 203 case ACL_OTHER: 204 pas->other = pa->e_perm; 205 break; 206 case ACL_MASK: 207 pas->mask = pa->e_perm; 208 break; 209 } 210 } 211 /* We'll only care about effective permissions: */ 212 pas->users &= pas->mask; 213 pas->group &= pas->mask; 214 pas->groups &= pas->mask; 215 } 216 217 /* We assume the acl has been verified with posix_acl_valid. */ 218 static void 219 _posix_to_nfsv4_one(struct posix_acl *pacl, struct nfs4_acl *acl, 220 unsigned int flags) 221 { 222 struct posix_acl_entry *pa, *group_owner_entry; 223 struct nfs4_ace *ace; 224 struct posix_acl_summary pas; 225 unsigned short deny; 226 int eflag = ((flags & NFS4_ACL_TYPE_DEFAULT) ? 227 NFS4_INHERITANCE_FLAGS | NFS4_ACE_INHERIT_ONLY_ACE : 0); 228 229 BUG_ON(pacl->a_count < 3); 230 summarize_posix_acl(pacl, &pas); 231 232 pa = pacl->a_entries; 233 ace = acl->aces + acl->naces; 234 235 /* We could deny everything not granted by the owner: */ 236 deny = ~pas.owner; 237 /* 238 * but it is equivalent (and simpler) to deny only what is not 239 * granted by later entries: 240 */ 241 deny &= pas.users | pas.group | pas.groups | pas.other; 242 if (deny) { 243 ace->type = NFS4_ACE_ACCESS_DENIED_ACE_TYPE; 244 ace->flag = eflag; 245 ace->access_mask = deny_mask_from_posix(deny, flags); 246 ace->whotype = NFS4_ACL_WHO_OWNER; 247 ace++; 248 acl->naces++; 249 } 250 251 ace->type = NFS4_ACE_ACCESS_ALLOWED_ACE_TYPE; 252 ace->flag = eflag; 253 ace->access_mask = mask_from_posix(pa->e_perm, flags | NFS4_ACL_OWNER); 254 ace->whotype = NFS4_ACL_WHO_OWNER; 255 ace++; 256 acl->naces++; 257 pa++; 258 259 while (pa->e_tag == ACL_USER) { 260 deny = ~(pa->e_perm & pas.mask); 261 deny &= pas.groups | pas.group | pas.other; 262 if (deny) { 263 ace->type = NFS4_ACE_ACCESS_DENIED_ACE_TYPE; 264 ace->flag = eflag; 265 ace->access_mask = deny_mask_from_posix(deny, flags); 266 ace->whotype = NFS4_ACL_WHO_NAMED; 267 ace->who = pa->e_id; 268 ace++; 269 acl->naces++; 270 } 271 ace->type = NFS4_ACE_ACCESS_ALLOWED_ACE_TYPE; 272 ace->flag = eflag; 273 ace->access_mask = mask_from_posix(pa->e_perm & pas.mask, 274 flags); 275 ace->whotype = NFS4_ACL_WHO_NAMED; 276 ace->who = pa->e_id; 277 ace++; 278 acl->naces++; 279 pa++; 280 } 281 282 /* In the case of groups, we apply allow ACEs first, then deny ACEs, 283 * since a user can be in more than one group. */ 284 285 /* allow ACEs */ 286 287 group_owner_entry = pa; 288 289 ace->type = NFS4_ACE_ACCESS_ALLOWED_ACE_TYPE; 290 ace->flag = eflag; 291 ace->access_mask = mask_from_posix(pas.group, flags); 292 ace->whotype = NFS4_ACL_WHO_GROUP; 293 ace++; 294 acl->naces++; 295 pa++; 296 297 while (pa->e_tag == ACL_GROUP) { 298 ace->type = NFS4_ACE_ACCESS_ALLOWED_ACE_TYPE; 299 ace->flag = eflag | NFS4_ACE_IDENTIFIER_GROUP; 300 ace->access_mask = mask_from_posix(pa->e_perm & pas.mask, 301 flags); 302 ace->whotype = NFS4_ACL_WHO_NAMED; 303 ace->who = pa->e_id; 304 ace++; 305 acl->naces++; 306 pa++; 307 } 308 309 /* deny ACEs */ 310 311 pa = group_owner_entry; 312 313 deny = ~pas.group & pas.other; 314 if (deny) { 315 ace->type = NFS4_ACE_ACCESS_DENIED_ACE_TYPE; 316 ace->flag = eflag; 317 ace->access_mask = deny_mask_from_posix(deny, flags); 318 ace->whotype = NFS4_ACL_WHO_GROUP; 319 ace++; 320 acl->naces++; 321 } 322 pa++; 323 324 while (pa->e_tag == ACL_GROUP) { 325 deny = ~(pa->e_perm & pas.mask); 326 deny &= pas.other; 327 if (deny) { 328 ace->type = NFS4_ACE_ACCESS_DENIED_ACE_TYPE; 329 ace->flag = eflag | NFS4_ACE_IDENTIFIER_GROUP; 330 ace->access_mask = deny_mask_from_posix(deny, flags); 331 ace->whotype = NFS4_ACL_WHO_NAMED; 332 ace->who = pa->e_id; 333 ace++; 334 acl->naces++; 335 } 336 pa++; 337 } 338 339 if (pa->e_tag == ACL_MASK) 340 pa++; 341 ace->type = NFS4_ACE_ACCESS_ALLOWED_ACE_TYPE; 342 ace->flag = eflag; 343 ace->access_mask = mask_from_posix(pa->e_perm, flags); 344 ace->whotype = NFS4_ACL_WHO_EVERYONE; 345 acl->naces++; 346 } 347 348 static void 349 sort_pacl_range(struct posix_acl *pacl, int start, int end) { 350 int sorted = 0, i; 351 struct posix_acl_entry tmp; 352 353 /* We just do a bubble sort; easy to do in place, and we're not 354 * expecting acl's to be long enough to justify anything more. */ 355 while (!sorted) { 356 sorted = 1; 357 for (i = start; i < end; i++) { 358 if (pacl->a_entries[i].e_id 359 > pacl->a_entries[i+1].e_id) { 360 sorted = 0; 361 tmp = pacl->a_entries[i]; 362 pacl->a_entries[i] = pacl->a_entries[i+1]; 363 pacl->a_entries[i+1] = tmp; 364 } 365 } 366 } 367 } 368 369 static void 370 sort_pacl(struct posix_acl *pacl) 371 { 372 /* posix_acl_valid requires that users and groups be in order 373 * by uid/gid. */ 374 int i, j; 375 376 if (pacl->a_count <= 4) 377 return; /* no users or groups */ 378 i = 1; 379 while (pacl->a_entries[i].e_tag == ACL_USER) 380 i++; 381 sort_pacl_range(pacl, 1, i-1); 382 383 BUG_ON(pacl->a_entries[i].e_tag != ACL_GROUP_OBJ); 384 j = ++i; 385 while (pacl->a_entries[j].e_tag == ACL_GROUP) 386 j++; 387 sort_pacl_range(pacl, i, j-1); 388 return; 389 } 390 391 /* 392 * While processing the NFSv4 ACE, this maintains bitmasks representing 393 * which permission bits have been allowed and which denied to a given 394 * entity: */ 395 struct posix_ace_state { 396 u32 allow; 397 u32 deny; 398 }; 399 400 struct posix_user_ace_state { 401 uid_t uid; 402 struct posix_ace_state perms; 403 }; 404 405 struct posix_ace_state_array { 406 int n; 407 struct posix_user_ace_state aces[]; 408 }; 409 410 /* 411 * While processing the NFSv4 ACE, this maintains the partial permissions 412 * calculated so far: */ 413 414 struct posix_acl_state { 415 int empty; 416 struct posix_ace_state owner; 417 struct posix_ace_state group; 418 struct posix_ace_state other; 419 struct posix_ace_state everyone; 420 struct posix_ace_state mask; /* Deny unused in this case */ 421 struct posix_ace_state_array *users; 422 struct posix_ace_state_array *groups; 423 }; 424 425 static int 426 init_state(struct posix_acl_state *state, int cnt) 427 { 428 int alloc; 429 430 memset(state, 0, sizeof(struct posix_acl_state)); 431 state->empty = 1; 432 /* 433 * In the worst case, each individual acl could be for a distinct 434 * named user or group, but we don't no which, so we allocate 435 * enough space for either: 436 */ 437 alloc = sizeof(struct posix_ace_state_array) 438 + cnt*sizeof(struct posix_user_ace_state); 439 state->users = kzalloc(alloc, GFP_KERNEL); 440 if (!state->users) 441 return -ENOMEM; 442 state->groups = kzalloc(alloc, GFP_KERNEL); 443 if (!state->groups) { 444 kfree(state->users); 445 return -ENOMEM; 446 } 447 return 0; 448 } 449 450 static void 451 free_state(struct posix_acl_state *state) { 452 kfree(state->users); 453 kfree(state->groups); 454 } 455 456 static inline void add_to_mask(struct posix_acl_state *state, struct posix_ace_state *astate) 457 { 458 state->mask.allow |= astate->allow; 459 } 460 461 /* 462 * Certain bits (SYNCHRONIZE, DELETE, WRITE_OWNER, READ/WRITE_NAMED_ATTRS, 463 * READ_ATTRIBUTES, READ_ACL) are currently unenforceable and don't translate 464 * to traditional read/write/execute permissions. 465 * 466 * It's problematic to reject acls that use certain mode bits, because it 467 * places the burden on users to learn the rules about which bits one 468 * particular server sets, without giving the user a lot of help--we return an 469 * error that could mean any number of different things. To make matters 470 * worse, the problematic bits might be introduced by some application that's 471 * automatically mapping from some other acl model. 472 * 473 * So wherever possible we accept anything, possibly erring on the side of 474 * denying more permissions than necessary. 475 * 476 * However we do reject *explicit* DENY's of a few bits representing 477 * permissions we could never deny: 478 */ 479 480 static inline int check_deny(u32 mask, int isowner) 481 { 482 if (mask & (NFS4_ACE_READ_ATTRIBUTES | NFS4_ACE_READ_ACL)) 483 return -EINVAL; 484 if (!isowner) 485 return 0; 486 if (mask & (NFS4_ACE_WRITE_ATTRIBUTES | NFS4_ACE_WRITE_ACL)) 487 return -EINVAL; 488 return 0; 489 } 490 491 static struct posix_acl * 492 posix_state_to_acl(struct posix_acl_state *state, unsigned int flags) 493 { 494 struct posix_acl_entry *pace; 495 struct posix_acl *pacl; 496 int nace; 497 int i, error = 0; 498 499 /* 500 * ACLs with no ACEs are treated differently in the inheritable 501 * and effective cases: when there are no inheritable ACEs, we 502 * set a zero-length default posix acl: 503 */ 504 if (state->empty && (flags & NFS4_ACL_TYPE_DEFAULT)) { 505 pacl = posix_acl_alloc(0, GFP_KERNEL); 506 return pacl ? pacl : ERR_PTR(-ENOMEM); 507 } 508 /* 509 * When there are no effective ACEs, the following will end 510 * up setting a 3-element effective posix ACL with all 511 * permissions zero. 512 */ 513 nace = 4 + state->users->n + state->groups->n; 514 pacl = posix_acl_alloc(nace, GFP_KERNEL); 515 if (!pacl) 516 return ERR_PTR(-ENOMEM); 517 518 pace = pacl->a_entries; 519 pace->e_tag = ACL_USER_OBJ; 520 error = check_deny(state->owner.deny, 1); 521 if (error) 522 goto out_err; 523 low_mode_from_nfs4(state->owner.allow, &pace->e_perm, flags); 524 pace->e_id = ACL_UNDEFINED_ID; 525 526 for (i=0; i < state->users->n; i++) { 527 pace++; 528 pace->e_tag = ACL_USER; 529 error = check_deny(state->users->aces[i].perms.deny, 0); 530 if (error) 531 goto out_err; 532 low_mode_from_nfs4(state->users->aces[i].perms.allow, 533 &pace->e_perm, flags); 534 pace->e_id = state->users->aces[i].uid; 535 add_to_mask(state, &state->users->aces[i].perms); 536 } 537 538 pace++; 539 pace->e_tag = ACL_GROUP_OBJ; 540 error = check_deny(state->group.deny, 0); 541 if (error) 542 goto out_err; 543 low_mode_from_nfs4(state->group.allow, &pace->e_perm, flags); 544 pace->e_id = ACL_UNDEFINED_ID; 545 add_to_mask(state, &state->group); 546 547 for (i=0; i < state->groups->n; i++) { 548 pace++; 549 pace->e_tag = ACL_GROUP; 550 error = check_deny(state->groups->aces[i].perms.deny, 0); 551 if (error) 552 goto out_err; 553 low_mode_from_nfs4(state->groups->aces[i].perms.allow, 554 &pace->e_perm, flags); 555 pace->e_id = state->groups->aces[i].uid; 556 add_to_mask(state, &state->groups->aces[i].perms); 557 } 558 559 pace++; 560 pace->e_tag = ACL_MASK; 561 low_mode_from_nfs4(state->mask.allow, &pace->e_perm, flags); 562 pace->e_id = ACL_UNDEFINED_ID; 563 564 pace++; 565 pace->e_tag = ACL_OTHER; 566 error = check_deny(state->other.deny, 0); 567 if (error) 568 goto out_err; 569 low_mode_from_nfs4(state->other.allow, &pace->e_perm, flags); 570 pace->e_id = ACL_UNDEFINED_ID; 571 572 return pacl; 573 out_err: 574 posix_acl_release(pacl); 575 return ERR_PTR(error); 576 } 577 578 static inline void allow_bits(struct posix_ace_state *astate, u32 mask) 579 { 580 /* Allow all bits in the mask not already denied: */ 581 astate->allow |= mask & ~astate->deny; 582 } 583 584 static inline void deny_bits(struct posix_ace_state *astate, u32 mask) 585 { 586 /* Deny all bits in the mask not already allowed: */ 587 astate->deny |= mask & ~astate->allow; 588 } 589 590 static int find_uid(struct posix_acl_state *state, struct posix_ace_state_array *a, uid_t uid) 591 { 592 int i; 593 594 for (i = 0; i < a->n; i++) 595 if (a->aces[i].uid == uid) 596 return i; 597 /* Not found: */ 598 a->n++; 599 a->aces[i].uid = uid; 600 a->aces[i].perms.allow = state->everyone.allow; 601 a->aces[i].perms.deny = state->everyone.deny; 602 603 return i; 604 } 605 606 static void deny_bits_array(struct posix_ace_state_array *a, u32 mask) 607 { 608 int i; 609 610 for (i=0; i < a->n; i++) 611 deny_bits(&a->aces[i].perms, mask); 612 } 613 614 static void allow_bits_array(struct posix_ace_state_array *a, u32 mask) 615 { 616 int i; 617 618 for (i=0; i < a->n; i++) 619 allow_bits(&a->aces[i].perms, mask); 620 } 621 622 static void process_one_v4_ace(struct posix_acl_state *state, 623 struct nfs4_ace *ace) 624 { 625 u32 mask = ace->access_mask; 626 int i; 627 628 state->empty = 0; 629 630 switch (ace2type(ace)) { 631 case ACL_USER_OBJ: 632 if (ace->type == NFS4_ACE_ACCESS_ALLOWED_ACE_TYPE) { 633 allow_bits(&state->owner, mask); 634 } else { 635 deny_bits(&state->owner, mask); 636 } 637 break; 638 case ACL_USER: 639 i = find_uid(state, state->users, ace->who); 640 if (ace->type == NFS4_ACE_ACCESS_ALLOWED_ACE_TYPE) { 641 allow_bits(&state->users->aces[i].perms, mask); 642 } else { 643 deny_bits(&state->users->aces[i].perms, mask); 644 mask = state->users->aces[i].perms.deny; 645 deny_bits(&state->owner, mask); 646 } 647 break; 648 case ACL_GROUP_OBJ: 649 if (ace->type == NFS4_ACE_ACCESS_ALLOWED_ACE_TYPE) { 650 allow_bits(&state->group, mask); 651 } else { 652 deny_bits(&state->group, mask); 653 mask = state->group.deny; 654 deny_bits(&state->owner, mask); 655 deny_bits(&state->everyone, mask); 656 deny_bits_array(state->users, mask); 657 deny_bits_array(state->groups, mask); 658 } 659 break; 660 case ACL_GROUP: 661 i = find_uid(state, state->groups, ace->who); 662 if (ace->type == NFS4_ACE_ACCESS_ALLOWED_ACE_TYPE) { 663 allow_bits(&state->groups->aces[i].perms, mask); 664 } else { 665 deny_bits(&state->groups->aces[i].perms, mask); 666 mask = state->groups->aces[i].perms.deny; 667 deny_bits(&state->owner, mask); 668 deny_bits(&state->group, mask); 669 deny_bits(&state->everyone, mask); 670 deny_bits_array(state->users, mask); 671 deny_bits_array(state->groups, mask); 672 } 673 break; 674 case ACL_OTHER: 675 if (ace->type == NFS4_ACE_ACCESS_ALLOWED_ACE_TYPE) { 676 allow_bits(&state->owner, mask); 677 allow_bits(&state->group, mask); 678 allow_bits(&state->other, mask); 679 allow_bits(&state->everyone, mask); 680 allow_bits_array(state->users, mask); 681 allow_bits_array(state->groups, mask); 682 } else { 683 deny_bits(&state->owner, mask); 684 deny_bits(&state->group, mask); 685 deny_bits(&state->other, mask); 686 deny_bits(&state->everyone, mask); 687 deny_bits_array(state->users, mask); 688 deny_bits_array(state->groups, mask); 689 } 690 } 691 } 692 693 int nfs4_acl_nfsv4_to_posix(struct nfs4_acl *acl, struct posix_acl **pacl, 694 struct posix_acl **dpacl, unsigned int flags) 695 { 696 struct posix_acl_state effective_acl_state, default_acl_state; 697 struct nfs4_ace *ace; 698 int ret; 699 700 ret = init_state(&effective_acl_state, acl->naces); 701 if (ret) 702 return ret; 703 ret = init_state(&default_acl_state, acl->naces); 704 if (ret) 705 goto out_estate; 706 ret = -EINVAL; 707 for (ace = acl->aces; ace < acl->aces + acl->naces; ace++) { 708 if (ace->type != NFS4_ACE_ACCESS_ALLOWED_ACE_TYPE && 709 ace->type != NFS4_ACE_ACCESS_DENIED_ACE_TYPE) 710 goto out_dstate; 711 if (ace->flag & ~NFS4_SUPPORTED_FLAGS) 712 goto out_dstate; 713 if ((ace->flag & NFS4_INHERITANCE_FLAGS) == 0) { 714 process_one_v4_ace(&effective_acl_state, ace); 715 continue; 716 } 717 if (!(flags & NFS4_ACL_DIR)) 718 goto out_dstate; 719 /* 720 * Note that when only one of FILE_INHERIT or DIRECTORY_INHERIT 721 * is set, we're effectively turning on the other. That's OK, 722 * according to rfc 3530. 723 */ 724 process_one_v4_ace(&default_acl_state, ace); 725 726 if (!(ace->flag & NFS4_ACE_INHERIT_ONLY_ACE)) 727 process_one_v4_ace(&effective_acl_state, ace); 728 } 729 *pacl = posix_state_to_acl(&effective_acl_state, flags); 730 if (IS_ERR(*pacl)) { 731 ret = PTR_ERR(*pacl); 732 *pacl = NULL; 733 goto out_dstate; 734 } 735 *dpacl = posix_state_to_acl(&default_acl_state, 736 flags | NFS4_ACL_TYPE_DEFAULT); 737 if (IS_ERR(*dpacl)) { 738 ret = PTR_ERR(*dpacl); 739 *dpacl = NULL; 740 posix_acl_release(*pacl); 741 *pacl = NULL; 742 goto out_dstate; 743 } 744 sort_pacl(*pacl); 745 sort_pacl(*dpacl); 746 ret = 0; 747 out_dstate: 748 free_state(&default_acl_state); 749 out_estate: 750 free_state(&effective_acl_state); 751 return ret; 752 } 753 754 static short 755 ace2type(struct nfs4_ace *ace) 756 { 757 switch (ace->whotype) { 758 case NFS4_ACL_WHO_NAMED: 759 return (ace->flag & NFS4_ACE_IDENTIFIER_GROUP ? 760 ACL_GROUP : ACL_USER); 761 case NFS4_ACL_WHO_OWNER: 762 return ACL_USER_OBJ; 763 case NFS4_ACL_WHO_GROUP: 764 return ACL_GROUP_OBJ; 765 case NFS4_ACL_WHO_EVERYONE: 766 return ACL_OTHER; 767 } 768 BUG(); 769 return -1; 770 } 771 772 EXPORT_SYMBOL(nfs4_acl_posix_to_nfsv4); 773 EXPORT_SYMBOL(nfs4_acl_nfsv4_to_posix); 774 775 struct nfs4_acl * 776 nfs4_acl_new(int n) 777 { 778 struct nfs4_acl *acl; 779 780 acl = kmalloc(sizeof(*acl) + n*sizeof(struct nfs4_ace), GFP_KERNEL); 781 if (acl == NULL) 782 return NULL; 783 acl->naces = 0; 784 return acl; 785 } 786 787 static struct { 788 char *string; 789 int stringlen; 790 int type; 791 } s2t_map[] = { 792 { 793 .string = "OWNER@", 794 .stringlen = sizeof("OWNER@") - 1, 795 .type = NFS4_ACL_WHO_OWNER, 796 }, 797 { 798 .string = "GROUP@", 799 .stringlen = sizeof("GROUP@") - 1, 800 .type = NFS4_ACL_WHO_GROUP, 801 }, 802 { 803 .string = "EVERYONE@", 804 .stringlen = sizeof("EVERYONE@") - 1, 805 .type = NFS4_ACL_WHO_EVERYONE, 806 }, 807 }; 808 809 int 810 nfs4_acl_get_whotype(char *p, u32 len) 811 { 812 int i; 813 814 for (i = 0; i < ARRAY_SIZE(s2t_map); i++) { 815 if (s2t_map[i].stringlen == len && 816 0 == memcmp(s2t_map[i].string, p, len)) 817 return s2t_map[i].type; 818 } 819 return NFS4_ACL_WHO_NAMED; 820 } 821 822 int 823 nfs4_acl_write_who(int who, char *p) 824 { 825 int i; 826 827 for (i = 0; i < ARRAY_SIZE(s2t_map); i++) { 828 if (s2t_map[i].type == who) { 829 memcpy(p, s2t_map[i].string, s2t_map[i].stringlen); 830 return s2t_map[i].stringlen; 831 } 832 } 833 BUG(); 834 return -1; 835 } 836 837 EXPORT_SYMBOL(nfs4_acl_new); 838 EXPORT_SYMBOL(nfs4_acl_get_whotype); 839 EXPORT_SYMBOL(nfs4_acl_write_who); 840