1 // SPDX-License-Identifier: LGPL-2.1+ 2 /* 3 * Copyright (C) International Business Machines Corp., 2007,2008 4 * Author(s): Steve French (sfrench@us.ibm.com) 5 * Copyright (C) 2020 Samsung Electronics Co., Ltd. 6 * Author(s): Namjae Jeon <linkinjeon@kernel.org> 7 */ 8 9 #include <linux/fs.h> 10 #include <linux/slab.h> 11 #include <linux/string.h> 12 #include <linux/mnt_idmapping.h> 13 14 #include "smbacl.h" 15 #include "smb_common.h" 16 #include "server.h" 17 #include "misc.h" 18 #include "mgmt/share_config.h" 19 20 static const struct smb_sid domain = {1, 4, {0, 0, 0, 0, 0, 5}, 21 {cpu_to_le32(21), cpu_to_le32(1), cpu_to_le32(2), cpu_to_le32(3), 22 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0} }; 23 24 /* security id for everyone/world system group */ 25 static const struct smb_sid creator_owner = { 26 1, 1, {0, 0, 0, 0, 0, 3}, {0} }; 27 /* security id for everyone/world system group */ 28 static const struct smb_sid creator_group = { 29 1, 1, {0, 0, 0, 0, 0, 3}, {cpu_to_le32(1)} }; 30 31 /* security id for everyone/world system group */ 32 static const struct smb_sid sid_everyone = { 33 1, 1, {0, 0, 0, 0, 0, 1}, {0} }; 34 /* security id for Authenticated Users system group */ 35 static const struct smb_sid sid_authusers = { 36 1, 1, {0, 0, 0, 0, 0, 5}, {cpu_to_le32(11)} }; 37 38 /* S-1-22-1 Unmapped Unix users */ 39 static const struct smb_sid sid_unix_users = {1, 1, {0, 0, 0, 0, 0, 22}, 40 {cpu_to_le32(1), 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0} }; 41 42 /* S-1-22-2 Unmapped Unix groups */ 43 static const struct smb_sid sid_unix_groups = { 1, 1, {0, 0, 0, 0, 0, 22}, 44 {cpu_to_le32(2), 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0} }; 45 46 /* 47 * See http://technet.microsoft.com/en-us/library/hh509017(v=ws.10).aspx 48 */ 49 50 /* S-1-5-88 MS NFS and Apple style UID/GID/mode */ 51 52 /* S-1-5-88-1 Unix uid */ 53 static const struct smb_sid sid_unix_NFS_users = { 1, 2, {0, 0, 0, 0, 0, 5}, 54 {cpu_to_le32(88), 55 cpu_to_le32(1), 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0} }; 56 57 /* S-1-5-88-2 Unix gid */ 58 static const struct smb_sid sid_unix_NFS_groups = { 1, 2, {0, 0, 0, 0, 0, 5}, 59 {cpu_to_le32(88), 60 cpu_to_le32(2), 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0} }; 61 62 /* S-1-5-88-3 Unix mode */ 63 static const struct smb_sid sid_unix_NFS_mode = { 1, 2, {0, 0, 0, 0, 0, 5}, 64 {cpu_to_le32(88), 65 cpu_to_le32(3), 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0} }; 66 67 /* 68 * if the two SIDs (roughly equivalent to a UUID for a user or group) are 69 * the same returns zero, if they do not match returns non-zero. 70 */ 71 int compare_sids(const struct smb_sid *ctsid, const struct smb_sid *cwsid) 72 { 73 int i; 74 int num_subauth, num_sat, num_saw; 75 76 if (!ctsid || !cwsid) 77 return 1; 78 79 /* compare the revision */ 80 if (ctsid->revision != cwsid->revision) { 81 if (ctsid->revision > cwsid->revision) 82 return 1; 83 else 84 return -1; 85 } 86 87 /* compare all of the six auth values */ 88 for (i = 0; i < NUM_AUTHS; ++i) { 89 if (ctsid->authority[i] != cwsid->authority[i]) { 90 if (ctsid->authority[i] > cwsid->authority[i]) 91 return 1; 92 else 93 return -1; 94 } 95 } 96 97 /* compare all of the subauth values if any */ 98 num_sat = ctsid->num_subauth; 99 num_saw = cwsid->num_subauth; 100 num_subauth = min(num_sat, num_saw); 101 if (num_subauth) { 102 for (i = 0; i < num_subauth; ++i) { 103 if (ctsid->sub_auth[i] != cwsid->sub_auth[i]) { 104 if (le32_to_cpu(ctsid->sub_auth[i]) > 105 le32_to_cpu(cwsid->sub_auth[i])) 106 return 1; 107 else 108 return -1; 109 } 110 } 111 } 112 113 return 0; /* sids compare/match */ 114 } 115 116 static void smb_copy_sid(struct smb_sid *dst, const struct smb_sid *src) 117 { 118 int i; 119 120 dst->revision = src->revision; 121 dst->num_subauth = min_t(u8, src->num_subauth, SID_MAX_SUB_AUTHORITIES); 122 for (i = 0; i < NUM_AUTHS; ++i) 123 dst->authority[i] = src->authority[i]; 124 for (i = 0; i < dst->num_subauth; ++i) 125 dst->sub_auth[i] = src->sub_auth[i]; 126 } 127 128 /* 129 * change posix mode to reflect permissions 130 * pmode is the existing mode (we only want to overwrite part of this 131 * bits to set can be: S_IRWXU, S_IRWXG or S_IRWXO ie 00700 or 00070 or 00007 132 */ 133 static umode_t access_flags_to_mode(struct smb_fattr *fattr, __le32 ace_flags, 134 int type) 135 { 136 __u32 flags = le32_to_cpu(ace_flags); 137 umode_t mode = 0; 138 139 if (flags & GENERIC_ALL) { 140 mode = 0777; 141 ksmbd_debug(SMB, "all perms\n"); 142 return mode; 143 } 144 145 if ((flags & GENERIC_READ) || (flags & FILE_READ_RIGHTS)) 146 mode = 0444; 147 if ((flags & GENERIC_WRITE) || (flags & FILE_WRITE_RIGHTS)) { 148 mode |= 0222; 149 if (S_ISDIR(fattr->cf_mode)) 150 mode |= 0111; 151 } 152 if ((flags & GENERIC_EXECUTE) || (flags & FILE_EXEC_RIGHTS)) 153 mode |= 0111; 154 155 if (type == ACCESS_DENIED_ACE_TYPE || type == ACCESS_DENIED_OBJECT_ACE_TYPE) 156 mode = ~mode; 157 158 ksmbd_debug(SMB, "access flags 0x%x mode now %04o\n", flags, mode); 159 160 return mode; 161 } 162 163 /* 164 * Generate access flags to reflect permissions mode is the existing mode. 165 * This function is called for every ACE in the DACL whose SID matches 166 * with either owner or group or everyone. 167 */ 168 static void mode_to_access_flags(umode_t mode, umode_t bits_to_use, 169 __u32 *pace_flags) 170 { 171 /* reset access mask */ 172 *pace_flags = 0x0; 173 174 /* bits to use are either S_IRWXU or S_IRWXG or S_IRWXO */ 175 mode &= bits_to_use; 176 177 /* 178 * check for R/W/X UGO since we do not know whose flags 179 * is this but we have cleared all the bits sans RWX for 180 * either user or group or other as per bits_to_use 181 */ 182 if (mode & 0444) 183 *pace_flags |= SET_FILE_READ_RIGHTS; 184 if (mode & 0222) 185 *pace_flags |= FILE_WRITE_RIGHTS; 186 if (mode & 0111) 187 *pace_flags |= SET_FILE_EXEC_RIGHTS; 188 189 ksmbd_debug(SMB, "mode: %o, access flags now 0x%x\n", 190 mode, *pace_flags); 191 } 192 193 static __u16 fill_ace_for_sid(struct smb_ace *pntace, 194 const struct smb_sid *psid, int type, int flags, 195 umode_t mode, umode_t bits) 196 { 197 int i; 198 __u16 size = 0; 199 __u32 access_req = 0; 200 201 pntace->type = type; 202 pntace->flags = flags; 203 mode_to_access_flags(mode, bits, &access_req); 204 if (!access_req) 205 access_req = SET_MINIMUM_RIGHTS; 206 pntace->access_req = cpu_to_le32(access_req); 207 208 pntace->sid.revision = psid->revision; 209 pntace->sid.num_subauth = psid->num_subauth; 210 for (i = 0; i < NUM_AUTHS; i++) 211 pntace->sid.authority[i] = psid->authority[i]; 212 for (i = 0; i < psid->num_subauth; i++) 213 pntace->sid.sub_auth[i] = psid->sub_auth[i]; 214 215 size = 1 + 1 + 2 + 4 + 1 + 1 + 6 + (psid->num_subauth * 4); 216 pntace->size = cpu_to_le16(size); 217 218 return size; 219 } 220 221 void id_to_sid(unsigned int cid, uint sidtype, struct smb_sid *ssid) 222 { 223 switch (sidtype) { 224 case SIDOWNER: 225 smb_copy_sid(ssid, &server_conf.domain_sid); 226 break; 227 case SIDUNIX_USER: 228 smb_copy_sid(ssid, &sid_unix_users); 229 break; 230 case SIDUNIX_GROUP: 231 smb_copy_sid(ssid, &sid_unix_groups); 232 break; 233 case SIDCREATOR_OWNER: 234 smb_copy_sid(ssid, &creator_owner); 235 return; 236 case SIDCREATOR_GROUP: 237 smb_copy_sid(ssid, &creator_group); 238 return; 239 case SIDNFS_USER: 240 smb_copy_sid(ssid, &sid_unix_NFS_users); 241 break; 242 case SIDNFS_GROUP: 243 smb_copy_sid(ssid, &sid_unix_NFS_groups); 244 break; 245 case SIDNFS_MODE: 246 smb_copy_sid(ssid, &sid_unix_NFS_mode); 247 break; 248 default: 249 return; 250 } 251 252 /* RID */ 253 ssid->sub_auth[ssid->num_subauth] = cpu_to_le32(cid); 254 ssid->num_subauth++; 255 } 256 257 static int sid_to_id(struct mnt_idmap *idmap, 258 struct smb_sid *psid, uint sidtype, 259 struct smb_fattr *fattr) 260 { 261 int rc = -EINVAL; 262 263 /* 264 * If we have too many subauthorities, then something is really wrong. 265 * Just return an error. 266 */ 267 if (unlikely(psid->num_subauth > SID_MAX_SUB_AUTHORITIES)) { 268 pr_err("%s: %u subauthorities is too many!\n", 269 __func__, psid->num_subauth); 270 return -EIO; 271 } 272 273 if (sidtype == SIDOWNER) { 274 kuid_t uid; 275 uid_t id; 276 277 id = le32_to_cpu(psid->sub_auth[psid->num_subauth - 1]); 278 uid = KUIDT_INIT(id); 279 uid = from_vfsuid(idmap, &init_user_ns, VFSUIDT_INIT(uid)); 280 if (uid_valid(uid)) { 281 fattr->cf_uid = uid; 282 rc = 0; 283 } 284 } else { 285 kgid_t gid; 286 gid_t id; 287 288 id = le32_to_cpu(psid->sub_auth[psid->num_subauth - 1]); 289 gid = KGIDT_INIT(id); 290 gid = from_vfsgid(idmap, &init_user_ns, VFSGIDT_INIT(gid)); 291 if (gid_valid(gid)) { 292 fattr->cf_gid = gid; 293 rc = 0; 294 } 295 } 296 297 return rc; 298 } 299 300 void posix_state_to_acl(struct posix_acl_state *state, 301 struct posix_acl_entry *pace) 302 { 303 int i; 304 305 pace->e_tag = ACL_USER_OBJ; 306 pace->e_perm = state->owner.allow; 307 for (i = 0; i < state->users->n; i++) { 308 pace++; 309 pace->e_tag = ACL_USER; 310 pace->e_uid = state->users->aces[i].uid; 311 pace->e_perm = state->users->aces[i].perms.allow; 312 } 313 314 pace++; 315 pace->e_tag = ACL_GROUP_OBJ; 316 pace->e_perm = state->group.allow; 317 318 for (i = 0; i < state->groups->n; i++) { 319 pace++; 320 pace->e_tag = ACL_GROUP; 321 pace->e_gid = state->groups->aces[i].gid; 322 pace->e_perm = state->groups->aces[i].perms.allow; 323 } 324 325 if (state->users->n || state->groups->n) { 326 pace++; 327 pace->e_tag = ACL_MASK; 328 pace->e_perm = state->mask.allow; 329 } 330 331 pace++; 332 pace->e_tag = ACL_OTHER; 333 pace->e_perm = state->other.allow; 334 } 335 336 int init_acl_state(struct posix_acl_state *state, int cnt) 337 { 338 int alloc; 339 340 memset(state, 0, sizeof(struct posix_acl_state)); 341 /* 342 * In the worst case, each individual acl could be for a distinct 343 * named user or group, but we don't know which, so we allocate 344 * enough space for either: 345 */ 346 alloc = sizeof(struct posix_ace_state_array) 347 + cnt * sizeof(struct posix_user_ace_state); 348 state->users = kzalloc(alloc, GFP_KERNEL); 349 if (!state->users) 350 return -ENOMEM; 351 state->groups = kzalloc(alloc, GFP_KERNEL); 352 if (!state->groups) { 353 kfree(state->users); 354 return -ENOMEM; 355 } 356 return 0; 357 } 358 359 void free_acl_state(struct posix_acl_state *state) 360 { 361 kfree(state->users); 362 kfree(state->groups); 363 } 364 365 static void parse_dacl(struct mnt_idmap *idmap, 366 struct smb_acl *pdacl, char *end_of_acl, 367 struct smb_sid *pownersid, struct smb_sid *pgrpsid, 368 struct smb_fattr *fattr) 369 { 370 int i, ret; 371 int num_aces = 0; 372 unsigned int acl_size; 373 char *acl_base; 374 struct smb_ace **ppace; 375 struct posix_acl_entry *cf_pace, *cf_pdace; 376 struct posix_acl_state acl_state, default_acl_state; 377 umode_t mode = 0, acl_mode; 378 bool owner_found = false, group_found = false, others_found = false; 379 380 if (!pdacl) 381 return; 382 383 /* validate that we do not go past end of acl */ 384 if (end_of_acl < (char *)pdacl + sizeof(struct smb_acl) || 385 end_of_acl < (char *)pdacl + le16_to_cpu(pdacl->size)) { 386 pr_err("ACL too small to parse DACL\n"); 387 return; 388 } 389 390 ksmbd_debug(SMB, "DACL revision %d size %d num aces %d\n", 391 le16_to_cpu(pdacl->revision), le16_to_cpu(pdacl->size), 392 le32_to_cpu(pdacl->num_aces)); 393 394 acl_base = (char *)pdacl; 395 acl_size = sizeof(struct smb_acl); 396 397 num_aces = le32_to_cpu(pdacl->num_aces); 398 if (num_aces <= 0) 399 return; 400 401 if (num_aces > ULONG_MAX / sizeof(struct smb_ace *)) 402 return; 403 404 ret = init_acl_state(&acl_state, num_aces); 405 if (ret) 406 return; 407 ret = init_acl_state(&default_acl_state, num_aces); 408 if (ret) { 409 free_acl_state(&acl_state); 410 return; 411 } 412 413 ppace = kmalloc_array(num_aces, sizeof(struct smb_ace *), GFP_KERNEL); 414 if (!ppace) { 415 free_acl_state(&default_acl_state); 416 free_acl_state(&acl_state); 417 return; 418 } 419 420 /* 421 * reset rwx permissions for user/group/other. 422 * Also, if num_aces is 0 i.e. DACL has no ACEs, 423 * user/group/other have no permissions 424 */ 425 for (i = 0; i < num_aces; ++i) { 426 if (end_of_acl - acl_base < acl_size) 427 break; 428 429 ppace[i] = (struct smb_ace *)(acl_base + acl_size); 430 acl_base = (char *)ppace[i]; 431 acl_size = offsetof(struct smb_ace, sid) + 432 offsetof(struct smb_sid, sub_auth); 433 434 if (end_of_acl - acl_base < acl_size || 435 ppace[i]->sid.num_subauth > SID_MAX_SUB_AUTHORITIES || 436 (end_of_acl - acl_base < 437 acl_size + sizeof(__le32) * ppace[i]->sid.num_subauth) || 438 (le16_to_cpu(ppace[i]->size) < 439 acl_size + sizeof(__le32) * ppace[i]->sid.num_subauth)) 440 break; 441 442 acl_size = le16_to_cpu(ppace[i]->size); 443 ppace[i]->access_req = 444 smb_map_generic_desired_access(ppace[i]->access_req); 445 446 if (!(compare_sids(&ppace[i]->sid, &sid_unix_NFS_mode))) { 447 fattr->cf_mode = 448 le32_to_cpu(ppace[i]->sid.sub_auth[2]); 449 break; 450 } else if (!compare_sids(&ppace[i]->sid, pownersid)) { 451 acl_mode = access_flags_to_mode(fattr, 452 ppace[i]->access_req, 453 ppace[i]->type); 454 acl_mode &= 0700; 455 456 if (!owner_found) { 457 mode &= ~(0700); 458 mode |= acl_mode; 459 } 460 owner_found = true; 461 } else if (!compare_sids(&ppace[i]->sid, pgrpsid) || 462 ppace[i]->sid.sub_auth[ppace[i]->sid.num_subauth - 1] == 463 DOMAIN_USER_RID_LE) { 464 acl_mode = access_flags_to_mode(fattr, 465 ppace[i]->access_req, 466 ppace[i]->type); 467 acl_mode &= 0070; 468 if (!group_found) { 469 mode &= ~(0070); 470 mode |= acl_mode; 471 } 472 group_found = true; 473 } else if (!compare_sids(&ppace[i]->sid, &sid_everyone)) { 474 acl_mode = access_flags_to_mode(fattr, 475 ppace[i]->access_req, 476 ppace[i]->type); 477 acl_mode &= 0007; 478 if (!others_found) { 479 mode &= ~(0007); 480 mode |= acl_mode; 481 } 482 others_found = true; 483 } else if (!compare_sids(&ppace[i]->sid, &creator_owner)) { 484 continue; 485 } else if (!compare_sids(&ppace[i]->sid, &creator_group)) { 486 continue; 487 } else if (!compare_sids(&ppace[i]->sid, &sid_authusers)) { 488 continue; 489 } else { 490 struct smb_fattr temp_fattr; 491 492 acl_mode = access_flags_to_mode(fattr, ppace[i]->access_req, 493 ppace[i]->type); 494 temp_fattr.cf_uid = INVALID_UID; 495 ret = sid_to_id(idmap, &ppace[i]->sid, SIDOWNER, &temp_fattr); 496 if (ret || uid_eq(temp_fattr.cf_uid, INVALID_UID)) { 497 pr_err("%s: Error %d mapping Owner SID to uid\n", 498 __func__, ret); 499 continue; 500 } 501 502 acl_state.owner.allow = ((acl_mode & 0700) >> 6) | 0004; 503 acl_state.users->aces[acl_state.users->n].uid = 504 temp_fattr.cf_uid; 505 acl_state.users->aces[acl_state.users->n++].perms.allow = 506 ((acl_mode & 0700) >> 6) | 0004; 507 default_acl_state.owner.allow = ((acl_mode & 0700) >> 6) | 0004; 508 default_acl_state.users->aces[default_acl_state.users->n].uid = 509 temp_fattr.cf_uid; 510 default_acl_state.users->aces[default_acl_state.users->n++].perms.allow = 511 ((acl_mode & 0700) >> 6) | 0004; 512 } 513 } 514 kfree(ppace); 515 516 if (owner_found) { 517 /* The owner must be set to at least read-only. */ 518 acl_state.owner.allow = ((mode & 0700) >> 6) | 0004; 519 acl_state.users->aces[acl_state.users->n].uid = fattr->cf_uid; 520 acl_state.users->aces[acl_state.users->n++].perms.allow = 521 ((mode & 0700) >> 6) | 0004; 522 default_acl_state.owner.allow = ((mode & 0700) >> 6) | 0004; 523 default_acl_state.users->aces[default_acl_state.users->n].uid = 524 fattr->cf_uid; 525 default_acl_state.users->aces[default_acl_state.users->n++].perms.allow = 526 ((mode & 0700) >> 6) | 0004; 527 } 528 529 if (group_found) { 530 acl_state.group.allow = (mode & 0070) >> 3; 531 acl_state.groups->aces[acl_state.groups->n].gid = 532 fattr->cf_gid; 533 acl_state.groups->aces[acl_state.groups->n++].perms.allow = 534 (mode & 0070) >> 3; 535 default_acl_state.group.allow = (mode & 0070) >> 3; 536 default_acl_state.groups->aces[default_acl_state.groups->n].gid = 537 fattr->cf_gid; 538 default_acl_state.groups->aces[default_acl_state.groups->n++].perms.allow = 539 (mode & 0070) >> 3; 540 } 541 542 if (others_found) { 543 fattr->cf_mode &= ~(0007); 544 fattr->cf_mode |= mode & 0007; 545 546 acl_state.other.allow = mode & 0007; 547 default_acl_state.other.allow = mode & 0007; 548 } 549 550 if (acl_state.users->n || acl_state.groups->n) { 551 acl_state.mask.allow = 0x07; 552 553 if (IS_ENABLED(CONFIG_FS_POSIX_ACL)) { 554 fattr->cf_acls = 555 posix_acl_alloc(acl_state.users->n + 556 acl_state.groups->n + 4, GFP_KERNEL); 557 if (fattr->cf_acls) { 558 cf_pace = fattr->cf_acls->a_entries; 559 posix_state_to_acl(&acl_state, cf_pace); 560 } 561 } 562 } 563 564 if (default_acl_state.users->n || default_acl_state.groups->n) { 565 default_acl_state.mask.allow = 0x07; 566 567 if (IS_ENABLED(CONFIG_FS_POSIX_ACL)) { 568 fattr->cf_dacls = 569 posix_acl_alloc(default_acl_state.users->n + 570 default_acl_state.groups->n + 4, GFP_KERNEL); 571 if (fattr->cf_dacls) { 572 cf_pdace = fattr->cf_dacls->a_entries; 573 posix_state_to_acl(&default_acl_state, cf_pdace); 574 } 575 } 576 } 577 free_acl_state(&acl_state); 578 free_acl_state(&default_acl_state); 579 } 580 581 static void set_posix_acl_entries_dacl(struct mnt_idmap *idmap, 582 struct smb_ace *pndace, 583 struct smb_fattr *fattr, u32 *num_aces, 584 u16 *size, u32 nt_aces_num) 585 { 586 struct posix_acl_entry *pace; 587 struct smb_sid *sid; 588 struct smb_ace *ntace; 589 int i, j; 590 591 if (!fattr->cf_acls) 592 goto posix_default_acl; 593 594 pace = fattr->cf_acls->a_entries; 595 for (i = 0; i < fattr->cf_acls->a_count; i++, pace++) { 596 int flags = 0; 597 598 sid = kmalloc(sizeof(struct smb_sid), GFP_KERNEL); 599 if (!sid) 600 break; 601 602 if (pace->e_tag == ACL_USER) { 603 uid_t uid; 604 unsigned int sid_type = SIDOWNER; 605 606 uid = posix_acl_uid_translate(idmap, pace); 607 if (!uid) 608 sid_type = SIDUNIX_USER; 609 id_to_sid(uid, sid_type, sid); 610 } else if (pace->e_tag == ACL_GROUP) { 611 gid_t gid; 612 613 gid = posix_acl_gid_translate(idmap, pace); 614 id_to_sid(gid, SIDUNIX_GROUP, sid); 615 } else if (pace->e_tag == ACL_OTHER && !nt_aces_num) { 616 smb_copy_sid(sid, &sid_everyone); 617 } else { 618 kfree(sid); 619 continue; 620 } 621 ntace = pndace; 622 for (j = 0; j < nt_aces_num; j++) { 623 if (ntace->sid.sub_auth[ntace->sid.num_subauth - 1] == 624 sid->sub_auth[sid->num_subauth - 1]) 625 goto pass_same_sid; 626 ntace = (struct smb_ace *)((char *)ntace + 627 le16_to_cpu(ntace->size)); 628 } 629 630 if (S_ISDIR(fattr->cf_mode) && pace->e_tag == ACL_OTHER) 631 flags = 0x03; 632 633 ntace = (struct smb_ace *)((char *)pndace + *size); 634 *size += fill_ace_for_sid(ntace, sid, ACCESS_ALLOWED, flags, 635 pace->e_perm, 0777); 636 (*num_aces)++; 637 if (pace->e_tag == ACL_USER) 638 ntace->access_req |= 639 FILE_DELETE_LE | FILE_DELETE_CHILD_LE; 640 641 if (S_ISDIR(fattr->cf_mode) && 642 (pace->e_tag == ACL_USER || pace->e_tag == ACL_GROUP)) { 643 ntace = (struct smb_ace *)((char *)pndace + *size); 644 *size += fill_ace_for_sid(ntace, sid, ACCESS_ALLOWED, 645 0x03, pace->e_perm, 0777); 646 (*num_aces)++; 647 if (pace->e_tag == ACL_USER) 648 ntace->access_req |= 649 FILE_DELETE_LE | FILE_DELETE_CHILD_LE; 650 } 651 652 pass_same_sid: 653 kfree(sid); 654 } 655 656 if (nt_aces_num) 657 return; 658 659 posix_default_acl: 660 if (!fattr->cf_dacls) 661 return; 662 663 pace = fattr->cf_dacls->a_entries; 664 for (i = 0; i < fattr->cf_dacls->a_count; i++, pace++) { 665 sid = kmalloc(sizeof(struct smb_sid), GFP_KERNEL); 666 if (!sid) 667 break; 668 669 if (pace->e_tag == ACL_USER) { 670 uid_t uid; 671 672 uid = posix_acl_uid_translate(idmap, pace); 673 id_to_sid(uid, SIDCREATOR_OWNER, sid); 674 } else if (pace->e_tag == ACL_GROUP) { 675 gid_t gid; 676 677 gid = posix_acl_gid_translate(idmap, pace); 678 id_to_sid(gid, SIDCREATOR_GROUP, sid); 679 } else { 680 kfree(sid); 681 continue; 682 } 683 684 ntace = (struct smb_ace *)((char *)pndace + *size); 685 *size += fill_ace_for_sid(ntace, sid, ACCESS_ALLOWED, 0x0b, 686 pace->e_perm, 0777); 687 (*num_aces)++; 688 if (pace->e_tag == ACL_USER) 689 ntace->access_req |= 690 FILE_DELETE_LE | FILE_DELETE_CHILD_LE; 691 kfree(sid); 692 } 693 } 694 695 static void set_ntacl_dacl(struct mnt_idmap *idmap, 696 struct smb_acl *pndacl, 697 struct smb_acl *nt_dacl, 698 unsigned int aces_size, 699 const struct smb_sid *pownersid, 700 const struct smb_sid *pgrpsid, 701 struct smb_fattr *fattr) 702 { 703 struct smb_ace *ntace, *pndace; 704 int nt_num_aces = le32_to_cpu(nt_dacl->num_aces), num_aces = 0; 705 unsigned short size = 0; 706 int i; 707 708 pndace = (struct smb_ace *)((char *)pndacl + sizeof(struct smb_acl)); 709 if (nt_num_aces) { 710 ntace = (struct smb_ace *)((char *)nt_dacl + sizeof(struct smb_acl)); 711 for (i = 0; i < nt_num_aces; i++) { 712 unsigned short nt_ace_size; 713 714 if (offsetof(struct smb_ace, access_req) > aces_size) 715 break; 716 717 nt_ace_size = le16_to_cpu(ntace->size); 718 if (nt_ace_size > aces_size) 719 break; 720 721 memcpy((char *)pndace + size, ntace, nt_ace_size); 722 size += nt_ace_size; 723 aces_size -= nt_ace_size; 724 ntace = (struct smb_ace *)((char *)ntace + nt_ace_size); 725 num_aces++; 726 } 727 } 728 729 set_posix_acl_entries_dacl(idmap, pndace, fattr, 730 &num_aces, &size, nt_num_aces); 731 pndacl->num_aces = cpu_to_le32(num_aces); 732 pndacl->size = cpu_to_le16(le16_to_cpu(pndacl->size) + size); 733 } 734 735 static void set_mode_dacl(struct mnt_idmap *idmap, 736 struct smb_acl *pndacl, struct smb_fattr *fattr) 737 { 738 struct smb_ace *pace, *pndace; 739 u32 num_aces = 0; 740 u16 size = 0, ace_size = 0; 741 uid_t uid; 742 const struct smb_sid *sid; 743 744 pace = pndace = (struct smb_ace *)((char *)pndacl + sizeof(struct smb_acl)); 745 746 if (fattr->cf_acls) { 747 set_posix_acl_entries_dacl(idmap, pndace, fattr, 748 &num_aces, &size, num_aces); 749 goto out; 750 } 751 752 /* owner RID */ 753 uid = from_kuid(&init_user_ns, fattr->cf_uid); 754 if (uid) 755 sid = &server_conf.domain_sid; 756 else 757 sid = &sid_unix_users; 758 ace_size = fill_ace_for_sid(pace, sid, ACCESS_ALLOWED, 0, 759 fattr->cf_mode, 0700); 760 pace->sid.sub_auth[pace->sid.num_subauth++] = cpu_to_le32(uid); 761 pace->size = cpu_to_le16(ace_size + 4); 762 size += le16_to_cpu(pace->size); 763 pace = (struct smb_ace *)((char *)pndace + size); 764 765 /* Group RID */ 766 ace_size = fill_ace_for_sid(pace, &sid_unix_groups, 767 ACCESS_ALLOWED, 0, fattr->cf_mode, 0070); 768 pace->sid.sub_auth[pace->sid.num_subauth++] = 769 cpu_to_le32(from_kgid(&init_user_ns, fattr->cf_gid)); 770 pace->size = cpu_to_le16(ace_size + 4); 771 size += le16_to_cpu(pace->size); 772 pace = (struct smb_ace *)((char *)pndace + size); 773 num_aces = 3; 774 775 if (S_ISDIR(fattr->cf_mode)) { 776 pace = (struct smb_ace *)((char *)pndace + size); 777 778 /* creator owner */ 779 size += fill_ace_for_sid(pace, &creator_owner, ACCESS_ALLOWED, 780 0x0b, fattr->cf_mode, 0700); 781 pace = (struct smb_ace *)((char *)pndace + size); 782 783 /* creator group */ 784 size += fill_ace_for_sid(pace, &creator_group, ACCESS_ALLOWED, 785 0x0b, fattr->cf_mode, 0070); 786 pace = (struct smb_ace *)((char *)pndace + size); 787 num_aces = 5; 788 } 789 790 /* other */ 791 size += fill_ace_for_sid(pace, &sid_everyone, ACCESS_ALLOWED, 0, 792 fattr->cf_mode, 0007); 793 794 out: 795 pndacl->num_aces = cpu_to_le32(num_aces); 796 pndacl->size = cpu_to_le16(le16_to_cpu(pndacl->size) + size); 797 } 798 799 static int parse_sid(struct smb_sid *psid, char *end_of_acl) 800 { 801 /* 802 * validate that we do not go past end of ACL - sid must be at least 8 803 * bytes long (assuming no sub-auths - e.g. the null SID 804 */ 805 if (end_of_acl < (char *)psid + 8) { 806 pr_err("ACL too small to parse SID %p\n", psid); 807 return -EINVAL; 808 } 809 810 return 0; 811 } 812 813 /* Convert CIFS ACL to POSIX form */ 814 int parse_sec_desc(struct mnt_idmap *idmap, struct smb_ntsd *pntsd, 815 int acl_len, struct smb_fattr *fattr) 816 { 817 int rc = 0; 818 struct smb_sid *owner_sid_ptr, *group_sid_ptr; 819 struct smb_acl *dacl_ptr; /* no need for SACL ptr */ 820 char *end_of_acl = ((char *)pntsd) + acl_len; 821 __u32 dacloffset; 822 int pntsd_type; 823 824 if (!pntsd) 825 return -EIO; 826 827 if (acl_len < sizeof(struct smb_ntsd)) 828 return -EINVAL; 829 830 owner_sid_ptr = (struct smb_sid *)((char *)pntsd + 831 le32_to_cpu(pntsd->osidoffset)); 832 group_sid_ptr = (struct smb_sid *)((char *)pntsd + 833 le32_to_cpu(pntsd->gsidoffset)); 834 dacloffset = le32_to_cpu(pntsd->dacloffset); 835 dacl_ptr = (struct smb_acl *)((char *)pntsd + dacloffset); 836 ksmbd_debug(SMB, 837 "revision %d type 0x%x ooffset 0x%x goffset 0x%x sacloffset 0x%x dacloffset 0x%x\n", 838 pntsd->revision, pntsd->type, le32_to_cpu(pntsd->osidoffset), 839 le32_to_cpu(pntsd->gsidoffset), 840 le32_to_cpu(pntsd->sacloffset), dacloffset); 841 842 pntsd_type = le16_to_cpu(pntsd->type); 843 if (!(pntsd_type & DACL_PRESENT)) { 844 ksmbd_debug(SMB, "DACL_PRESENT in DACL type is not set\n"); 845 return rc; 846 } 847 848 pntsd->type = cpu_to_le16(DACL_PRESENT); 849 850 if (pntsd->osidoffset) { 851 rc = parse_sid(owner_sid_ptr, end_of_acl); 852 if (rc) { 853 pr_err("%s: Error %d parsing Owner SID\n", __func__, rc); 854 return rc; 855 } 856 857 rc = sid_to_id(idmap, owner_sid_ptr, SIDOWNER, fattr); 858 if (rc) { 859 pr_err("%s: Error %d mapping Owner SID to uid\n", 860 __func__, rc); 861 owner_sid_ptr = NULL; 862 } 863 } 864 865 if (pntsd->gsidoffset) { 866 rc = parse_sid(group_sid_ptr, end_of_acl); 867 if (rc) { 868 pr_err("%s: Error %d mapping Owner SID to gid\n", 869 __func__, rc); 870 return rc; 871 } 872 rc = sid_to_id(idmap, group_sid_ptr, SIDUNIX_GROUP, fattr); 873 if (rc) { 874 pr_err("%s: Error %d mapping Group SID to gid\n", 875 __func__, rc); 876 group_sid_ptr = NULL; 877 } 878 } 879 880 if ((pntsd_type & (DACL_AUTO_INHERITED | DACL_AUTO_INHERIT_REQ)) == 881 (DACL_AUTO_INHERITED | DACL_AUTO_INHERIT_REQ)) 882 pntsd->type |= cpu_to_le16(DACL_AUTO_INHERITED); 883 if (pntsd_type & DACL_PROTECTED) 884 pntsd->type |= cpu_to_le16(DACL_PROTECTED); 885 886 if (dacloffset) { 887 parse_dacl(idmap, dacl_ptr, end_of_acl, 888 owner_sid_ptr, group_sid_ptr, fattr); 889 } 890 891 return 0; 892 } 893 894 /* Convert permission bits from mode to equivalent CIFS ACL */ 895 int build_sec_desc(struct mnt_idmap *idmap, 896 struct smb_ntsd *pntsd, struct smb_ntsd *ppntsd, 897 int ppntsd_size, int addition_info, __u32 *secdesclen, 898 struct smb_fattr *fattr) 899 { 900 int rc = 0; 901 __u32 offset; 902 struct smb_sid *owner_sid_ptr, *group_sid_ptr; 903 struct smb_sid *nowner_sid_ptr, *ngroup_sid_ptr; 904 struct smb_acl *dacl_ptr = NULL; /* no need for SACL ptr */ 905 uid_t uid; 906 gid_t gid; 907 unsigned int sid_type = SIDOWNER; 908 909 nowner_sid_ptr = kmalloc(sizeof(struct smb_sid), GFP_KERNEL); 910 if (!nowner_sid_ptr) 911 return -ENOMEM; 912 913 uid = from_kuid(&init_user_ns, fattr->cf_uid); 914 if (!uid) 915 sid_type = SIDUNIX_USER; 916 id_to_sid(uid, sid_type, nowner_sid_ptr); 917 918 ngroup_sid_ptr = kmalloc(sizeof(struct smb_sid), GFP_KERNEL); 919 if (!ngroup_sid_ptr) { 920 kfree(nowner_sid_ptr); 921 return -ENOMEM; 922 } 923 924 gid = from_kgid(&init_user_ns, fattr->cf_gid); 925 id_to_sid(gid, SIDUNIX_GROUP, ngroup_sid_ptr); 926 927 offset = sizeof(struct smb_ntsd); 928 pntsd->sacloffset = 0; 929 pntsd->revision = cpu_to_le16(1); 930 pntsd->type = cpu_to_le16(SELF_RELATIVE); 931 if (ppntsd) 932 pntsd->type |= ppntsd->type; 933 934 if (addition_info & OWNER_SECINFO) { 935 pntsd->osidoffset = cpu_to_le32(offset); 936 owner_sid_ptr = (struct smb_sid *)((char *)pntsd + offset); 937 smb_copy_sid(owner_sid_ptr, nowner_sid_ptr); 938 offset += 1 + 1 + 6 + (nowner_sid_ptr->num_subauth * 4); 939 } 940 941 if (addition_info & GROUP_SECINFO) { 942 pntsd->gsidoffset = cpu_to_le32(offset); 943 group_sid_ptr = (struct smb_sid *)((char *)pntsd + offset); 944 smb_copy_sid(group_sid_ptr, ngroup_sid_ptr); 945 offset += 1 + 1 + 6 + (ngroup_sid_ptr->num_subauth * 4); 946 } 947 948 if (addition_info & DACL_SECINFO) { 949 pntsd->type |= cpu_to_le16(DACL_PRESENT); 950 dacl_ptr = (struct smb_acl *)((char *)pntsd + offset); 951 dacl_ptr->revision = cpu_to_le16(2); 952 dacl_ptr->size = cpu_to_le16(sizeof(struct smb_acl)); 953 dacl_ptr->num_aces = 0; 954 955 if (!ppntsd) { 956 set_mode_dacl(idmap, dacl_ptr, fattr); 957 } else { 958 struct smb_acl *ppdacl_ptr; 959 unsigned int dacl_offset = le32_to_cpu(ppntsd->dacloffset); 960 int ppdacl_size, ntacl_size = ppntsd_size - dacl_offset; 961 962 if (!dacl_offset || 963 (dacl_offset + sizeof(struct smb_acl) > ppntsd_size)) 964 goto out; 965 966 ppdacl_ptr = (struct smb_acl *)((char *)ppntsd + dacl_offset); 967 ppdacl_size = le16_to_cpu(ppdacl_ptr->size); 968 if (ppdacl_size > ntacl_size || 969 ppdacl_size < sizeof(struct smb_acl)) 970 goto out; 971 972 set_ntacl_dacl(idmap, dacl_ptr, ppdacl_ptr, 973 ntacl_size - sizeof(struct smb_acl), 974 nowner_sid_ptr, ngroup_sid_ptr, 975 fattr); 976 } 977 pntsd->dacloffset = cpu_to_le32(offset); 978 offset += le16_to_cpu(dacl_ptr->size); 979 } 980 981 out: 982 kfree(nowner_sid_ptr); 983 kfree(ngroup_sid_ptr); 984 *secdesclen = offset; 985 return rc; 986 } 987 988 static void smb_set_ace(struct smb_ace *ace, const struct smb_sid *sid, u8 type, 989 u8 flags, __le32 access_req) 990 { 991 ace->type = type; 992 ace->flags = flags; 993 ace->access_req = access_req; 994 smb_copy_sid(&ace->sid, sid); 995 ace->size = cpu_to_le16(1 + 1 + 2 + 4 + 1 + 1 + 6 + (sid->num_subauth * 4)); 996 } 997 998 int smb_inherit_dacl(struct ksmbd_conn *conn, 999 const struct path *path, 1000 unsigned int uid, unsigned int gid) 1001 { 1002 const struct smb_sid *psid, *creator = NULL; 1003 struct smb_ace *parent_aces, *aces; 1004 struct smb_acl *parent_pdacl; 1005 struct smb_ntsd *parent_pntsd = NULL; 1006 struct smb_sid owner_sid, group_sid; 1007 struct dentry *parent = path->dentry->d_parent; 1008 struct mnt_idmap *idmap = mnt_idmap(path->mnt); 1009 int inherited_flags = 0, flags = 0, i, ace_cnt = 0, nt_size = 0, pdacl_size; 1010 int rc = 0, num_aces, dacloffset, pntsd_type, pntsd_size, acl_len, aces_size; 1011 char *aces_base; 1012 bool is_dir = S_ISDIR(d_inode(path->dentry)->i_mode); 1013 1014 pntsd_size = ksmbd_vfs_get_sd_xattr(conn, idmap, 1015 parent, &parent_pntsd); 1016 if (pntsd_size <= 0) 1017 return -ENOENT; 1018 dacloffset = le32_to_cpu(parent_pntsd->dacloffset); 1019 if (!dacloffset || (dacloffset + sizeof(struct smb_acl) > pntsd_size)) { 1020 rc = -EINVAL; 1021 goto free_parent_pntsd; 1022 } 1023 1024 parent_pdacl = (struct smb_acl *)((char *)parent_pntsd + dacloffset); 1025 acl_len = pntsd_size - dacloffset; 1026 num_aces = le32_to_cpu(parent_pdacl->num_aces); 1027 pntsd_type = le16_to_cpu(parent_pntsd->type); 1028 pdacl_size = le16_to_cpu(parent_pdacl->size); 1029 1030 if (pdacl_size > acl_len || pdacl_size < sizeof(struct smb_acl)) { 1031 rc = -EINVAL; 1032 goto free_parent_pntsd; 1033 } 1034 1035 aces_base = kmalloc(sizeof(struct smb_ace) * num_aces * 2, GFP_KERNEL); 1036 if (!aces_base) { 1037 rc = -ENOMEM; 1038 goto free_parent_pntsd; 1039 } 1040 1041 aces = (struct smb_ace *)aces_base; 1042 parent_aces = (struct smb_ace *)((char *)parent_pdacl + 1043 sizeof(struct smb_acl)); 1044 aces_size = acl_len - sizeof(struct smb_acl); 1045 1046 if (pntsd_type & DACL_AUTO_INHERITED) 1047 inherited_flags = INHERITED_ACE; 1048 1049 for (i = 0; i < num_aces; i++) { 1050 int pace_size; 1051 1052 if (offsetof(struct smb_ace, access_req) > aces_size) 1053 break; 1054 1055 pace_size = le16_to_cpu(parent_aces->size); 1056 if (pace_size > aces_size) 1057 break; 1058 1059 aces_size -= pace_size; 1060 1061 flags = parent_aces->flags; 1062 if (!smb_inherit_flags(flags, is_dir)) 1063 goto pass; 1064 if (is_dir) { 1065 flags &= ~(INHERIT_ONLY_ACE | INHERITED_ACE); 1066 if (!(flags & CONTAINER_INHERIT_ACE)) 1067 flags |= INHERIT_ONLY_ACE; 1068 if (flags & NO_PROPAGATE_INHERIT_ACE) 1069 flags = 0; 1070 } else { 1071 flags = 0; 1072 } 1073 1074 if (!compare_sids(&creator_owner, &parent_aces->sid)) { 1075 creator = &creator_owner; 1076 id_to_sid(uid, SIDOWNER, &owner_sid); 1077 psid = &owner_sid; 1078 } else if (!compare_sids(&creator_group, &parent_aces->sid)) { 1079 creator = &creator_group; 1080 id_to_sid(gid, SIDUNIX_GROUP, &group_sid); 1081 psid = &group_sid; 1082 } else { 1083 creator = NULL; 1084 psid = &parent_aces->sid; 1085 } 1086 1087 if (is_dir && creator && flags & CONTAINER_INHERIT_ACE) { 1088 smb_set_ace(aces, psid, parent_aces->type, inherited_flags, 1089 parent_aces->access_req); 1090 nt_size += le16_to_cpu(aces->size); 1091 ace_cnt++; 1092 aces = (struct smb_ace *)((char *)aces + le16_to_cpu(aces->size)); 1093 flags |= INHERIT_ONLY_ACE; 1094 psid = creator; 1095 } else if (is_dir && !(parent_aces->flags & NO_PROPAGATE_INHERIT_ACE)) { 1096 psid = &parent_aces->sid; 1097 } 1098 1099 smb_set_ace(aces, psid, parent_aces->type, flags | inherited_flags, 1100 parent_aces->access_req); 1101 nt_size += le16_to_cpu(aces->size); 1102 aces = (struct smb_ace *)((char *)aces + le16_to_cpu(aces->size)); 1103 ace_cnt++; 1104 pass: 1105 parent_aces = (struct smb_ace *)((char *)parent_aces + pace_size); 1106 } 1107 1108 if (nt_size > 0) { 1109 struct smb_ntsd *pntsd; 1110 struct smb_acl *pdacl; 1111 struct smb_sid *powner_sid = NULL, *pgroup_sid = NULL; 1112 int powner_sid_size = 0, pgroup_sid_size = 0, pntsd_size; 1113 int pntsd_alloc_size; 1114 1115 if (parent_pntsd->osidoffset) { 1116 powner_sid = (struct smb_sid *)((char *)parent_pntsd + 1117 le32_to_cpu(parent_pntsd->osidoffset)); 1118 powner_sid_size = 1 + 1 + 6 + (powner_sid->num_subauth * 4); 1119 } 1120 if (parent_pntsd->gsidoffset) { 1121 pgroup_sid = (struct smb_sid *)((char *)parent_pntsd + 1122 le32_to_cpu(parent_pntsd->gsidoffset)); 1123 pgroup_sid_size = 1 + 1 + 6 + (pgroup_sid->num_subauth * 4); 1124 } 1125 1126 pntsd_alloc_size = sizeof(struct smb_ntsd) + powner_sid_size + 1127 pgroup_sid_size + sizeof(struct smb_acl) + nt_size; 1128 1129 pntsd = kzalloc(pntsd_alloc_size, GFP_KERNEL); 1130 if (!pntsd) { 1131 rc = -ENOMEM; 1132 goto free_aces_base; 1133 } 1134 1135 pntsd->revision = cpu_to_le16(1); 1136 pntsd->type = cpu_to_le16(SELF_RELATIVE | DACL_PRESENT); 1137 if (le16_to_cpu(parent_pntsd->type) & DACL_AUTO_INHERITED) 1138 pntsd->type |= cpu_to_le16(DACL_AUTO_INHERITED); 1139 pntsd_size = sizeof(struct smb_ntsd); 1140 pntsd->osidoffset = parent_pntsd->osidoffset; 1141 pntsd->gsidoffset = parent_pntsd->gsidoffset; 1142 pntsd->dacloffset = parent_pntsd->dacloffset; 1143 1144 if ((u64)le32_to_cpu(pntsd->osidoffset) + powner_sid_size > 1145 pntsd_alloc_size) { 1146 rc = -EINVAL; 1147 kfree(pntsd); 1148 goto free_aces_base; 1149 } 1150 1151 if ((u64)le32_to_cpu(pntsd->gsidoffset) + pgroup_sid_size > 1152 pntsd_alloc_size) { 1153 rc = -EINVAL; 1154 kfree(pntsd); 1155 goto free_aces_base; 1156 } 1157 1158 if ((u64)le32_to_cpu(pntsd->dacloffset) + sizeof(struct smb_acl) + nt_size > 1159 pntsd_alloc_size) { 1160 rc = -EINVAL; 1161 kfree(pntsd); 1162 goto free_aces_base; 1163 } 1164 1165 if (pntsd->osidoffset) { 1166 struct smb_sid *owner_sid = (struct smb_sid *)((char *)pntsd + 1167 le32_to_cpu(pntsd->osidoffset)); 1168 memcpy(owner_sid, powner_sid, powner_sid_size); 1169 pntsd_size += powner_sid_size; 1170 } 1171 1172 if (pntsd->gsidoffset) { 1173 struct smb_sid *group_sid = (struct smb_sid *)((char *)pntsd + 1174 le32_to_cpu(pntsd->gsidoffset)); 1175 memcpy(group_sid, pgroup_sid, pgroup_sid_size); 1176 pntsd_size += pgroup_sid_size; 1177 } 1178 1179 if (pntsd->dacloffset) { 1180 struct smb_ace *pace; 1181 1182 pdacl = (struct smb_acl *)((char *)pntsd + le32_to_cpu(pntsd->dacloffset)); 1183 pdacl->revision = cpu_to_le16(2); 1184 pdacl->size = cpu_to_le16(sizeof(struct smb_acl) + nt_size); 1185 pdacl->num_aces = cpu_to_le32(ace_cnt); 1186 pace = (struct smb_ace *)((char *)pdacl + sizeof(struct smb_acl)); 1187 memcpy(pace, aces_base, nt_size); 1188 pntsd_size += sizeof(struct smb_acl) + nt_size; 1189 } 1190 1191 ksmbd_vfs_set_sd_xattr(conn, idmap, path, pntsd, pntsd_size, false); 1192 kfree(pntsd); 1193 } 1194 1195 free_aces_base: 1196 kfree(aces_base); 1197 free_parent_pntsd: 1198 kfree(parent_pntsd); 1199 return rc; 1200 } 1201 1202 bool smb_inherit_flags(int flags, bool is_dir) 1203 { 1204 if (!is_dir) 1205 return (flags & OBJECT_INHERIT_ACE) != 0; 1206 1207 if (flags & OBJECT_INHERIT_ACE && !(flags & NO_PROPAGATE_INHERIT_ACE)) 1208 return true; 1209 1210 if (flags & CONTAINER_INHERIT_ACE) 1211 return true; 1212 return false; 1213 } 1214 1215 int smb_check_perm_dacl(struct ksmbd_conn *conn, const struct path *path, 1216 __le32 *pdaccess, int uid) 1217 { 1218 struct mnt_idmap *idmap = mnt_idmap(path->mnt); 1219 struct smb_ntsd *pntsd = NULL; 1220 struct smb_acl *pdacl; 1221 struct posix_acl *posix_acls; 1222 int rc = 0, pntsd_size, acl_size, aces_size, pdacl_size, dacl_offset; 1223 struct smb_sid sid; 1224 int granted = le32_to_cpu(*pdaccess & ~FILE_MAXIMAL_ACCESS_LE); 1225 struct smb_ace *ace; 1226 int i, found = 0; 1227 unsigned int access_bits = 0; 1228 struct smb_ace *others_ace = NULL; 1229 struct posix_acl_entry *pa_entry; 1230 unsigned int sid_type = SIDOWNER; 1231 unsigned short ace_size; 1232 1233 ksmbd_debug(SMB, "check permission using windows acl\n"); 1234 pntsd_size = ksmbd_vfs_get_sd_xattr(conn, idmap, 1235 path->dentry, &pntsd); 1236 if (pntsd_size <= 0 || !pntsd) 1237 goto err_out; 1238 1239 dacl_offset = le32_to_cpu(pntsd->dacloffset); 1240 if (!dacl_offset || 1241 (dacl_offset + sizeof(struct smb_acl) > pntsd_size)) 1242 goto err_out; 1243 1244 pdacl = (struct smb_acl *)((char *)pntsd + le32_to_cpu(pntsd->dacloffset)); 1245 acl_size = pntsd_size - dacl_offset; 1246 pdacl_size = le16_to_cpu(pdacl->size); 1247 1248 if (pdacl_size > acl_size || pdacl_size < sizeof(struct smb_acl)) 1249 goto err_out; 1250 1251 if (!pdacl->num_aces) { 1252 if (!(pdacl_size - sizeof(struct smb_acl)) && 1253 *pdaccess & ~(FILE_READ_CONTROL_LE | FILE_WRITE_DAC_LE)) { 1254 rc = -EACCES; 1255 goto err_out; 1256 } 1257 goto err_out; 1258 } 1259 1260 if (*pdaccess & FILE_MAXIMAL_ACCESS_LE) { 1261 granted = READ_CONTROL | WRITE_DAC | FILE_READ_ATTRIBUTES | 1262 DELETE; 1263 1264 ace = (struct smb_ace *)((char *)pdacl + sizeof(struct smb_acl)); 1265 aces_size = acl_size - sizeof(struct smb_acl); 1266 for (i = 0; i < le32_to_cpu(pdacl->num_aces); i++) { 1267 if (offsetof(struct smb_ace, access_req) > aces_size) 1268 break; 1269 ace_size = le16_to_cpu(ace->size); 1270 if (ace_size > aces_size) 1271 break; 1272 aces_size -= ace_size; 1273 granted |= le32_to_cpu(ace->access_req); 1274 ace = (struct smb_ace *)((char *)ace + le16_to_cpu(ace->size)); 1275 } 1276 1277 if (!pdacl->num_aces) 1278 granted = GENERIC_ALL_FLAGS; 1279 } 1280 1281 if (!uid) 1282 sid_type = SIDUNIX_USER; 1283 id_to_sid(uid, sid_type, &sid); 1284 1285 ace = (struct smb_ace *)((char *)pdacl + sizeof(struct smb_acl)); 1286 aces_size = acl_size - sizeof(struct smb_acl); 1287 for (i = 0; i < le32_to_cpu(pdacl->num_aces); i++) { 1288 if (offsetof(struct smb_ace, access_req) > aces_size) 1289 break; 1290 ace_size = le16_to_cpu(ace->size); 1291 if (ace_size > aces_size) 1292 break; 1293 aces_size -= ace_size; 1294 1295 if (!compare_sids(&sid, &ace->sid) || 1296 !compare_sids(&sid_unix_NFS_mode, &ace->sid)) { 1297 found = 1; 1298 break; 1299 } 1300 if (!compare_sids(&sid_everyone, &ace->sid)) 1301 others_ace = ace; 1302 1303 ace = (struct smb_ace *)((char *)ace + le16_to_cpu(ace->size)); 1304 } 1305 1306 if (*pdaccess & FILE_MAXIMAL_ACCESS_LE && found) { 1307 granted = READ_CONTROL | WRITE_DAC | FILE_READ_ATTRIBUTES | 1308 DELETE; 1309 1310 granted |= le32_to_cpu(ace->access_req); 1311 1312 if (!pdacl->num_aces) 1313 granted = GENERIC_ALL_FLAGS; 1314 } 1315 1316 if (IS_ENABLED(CONFIG_FS_POSIX_ACL)) { 1317 posix_acls = get_inode_acl(d_inode(path->dentry), ACL_TYPE_ACCESS); 1318 if (!IS_ERR_OR_NULL(posix_acls) && !found) { 1319 unsigned int id = -1; 1320 1321 pa_entry = posix_acls->a_entries; 1322 for (i = 0; i < posix_acls->a_count; i++, pa_entry++) { 1323 if (pa_entry->e_tag == ACL_USER) 1324 id = posix_acl_uid_translate(idmap, pa_entry); 1325 else if (pa_entry->e_tag == ACL_GROUP) 1326 id = posix_acl_gid_translate(idmap, pa_entry); 1327 else 1328 continue; 1329 1330 if (id == uid) { 1331 mode_to_access_flags(pa_entry->e_perm, 1332 0777, 1333 &access_bits); 1334 if (!access_bits) 1335 access_bits = 1336 SET_MINIMUM_RIGHTS; 1337 posix_acl_release(posix_acls); 1338 goto check_access_bits; 1339 } 1340 } 1341 } 1342 if (!IS_ERR_OR_NULL(posix_acls)) 1343 posix_acl_release(posix_acls); 1344 } 1345 1346 if (!found) { 1347 if (others_ace) { 1348 ace = others_ace; 1349 } else { 1350 ksmbd_debug(SMB, "Can't find corresponding sid\n"); 1351 rc = -EACCES; 1352 goto err_out; 1353 } 1354 } 1355 1356 switch (ace->type) { 1357 case ACCESS_ALLOWED_ACE_TYPE: 1358 access_bits = le32_to_cpu(ace->access_req); 1359 break; 1360 case ACCESS_DENIED_ACE_TYPE: 1361 case ACCESS_DENIED_CALLBACK_ACE_TYPE: 1362 access_bits = le32_to_cpu(~ace->access_req); 1363 break; 1364 } 1365 1366 check_access_bits: 1367 if (granted & 1368 ~(access_bits | FILE_READ_ATTRIBUTES | READ_CONTROL | WRITE_DAC | DELETE)) { 1369 ksmbd_debug(SMB, "Access denied with winACL, granted : %x, access_req : %x\n", 1370 granted, le32_to_cpu(ace->access_req)); 1371 rc = -EACCES; 1372 goto err_out; 1373 } 1374 1375 *pdaccess = cpu_to_le32(granted); 1376 err_out: 1377 kfree(pntsd); 1378 return rc; 1379 } 1380 1381 int set_info_sec(struct ksmbd_conn *conn, struct ksmbd_tree_connect *tcon, 1382 const struct path *path, struct smb_ntsd *pntsd, int ntsd_len, 1383 bool type_check, bool get_write) 1384 { 1385 int rc; 1386 struct smb_fattr fattr = {{0}}; 1387 struct inode *inode = d_inode(path->dentry); 1388 struct mnt_idmap *idmap = mnt_idmap(path->mnt); 1389 struct iattr newattrs; 1390 1391 fattr.cf_uid = INVALID_UID; 1392 fattr.cf_gid = INVALID_GID; 1393 fattr.cf_mode = inode->i_mode; 1394 1395 rc = parse_sec_desc(idmap, pntsd, ntsd_len, &fattr); 1396 if (rc) 1397 goto out; 1398 1399 newattrs.ia_valid = ATTR_CTIME; 1400 if (!uid_eq(fattr.cf_uid, INVALID_UID)) { 1401 newattrs.ia_valid |= ATTR_UID; 1402 newattrs.ia_uid = fattr.cf_uid; 1403 } 1404 if (!gid_eq(fattr.cf_gid, INVALID_GID)) { 1405 newattrs.ia_valid |= ATTR_GID; 1406 newattrs.ia_gid = fattr.cf_gid; 1407 } 1408 newattrs.ia_valid |= ATTR_MODE; 1409 newattrs.ia_mode = (inode->i_mode & ~0777) | (fattr.cf_mode & 0777); 1410 1411 ksmbd_vfs_remove_acl_xattrs(idmap, path); 1412 /* Update posix acls */ 1413 if (IS_ENABLED(CONFIG_FS_POSIX_ACL) && fattr.cf_dacls) { 1414 rc = set_posix_acl(idmap, path->dentry, 1415 ACL_TYPE_ACCESS, fattr.cf_acls); 1416 if (rc < 0) 1417 ksmbd_debug(SMB, 1418 "Set posix acl(ACL_TYPE_ACCESS) failed, rc : %d\n", 1419 rc); 1420 if (S_ISDIR(inode->i_mode) && fattr.cf_dacls) { 1421 rc = set_posix_acl(idmap, path->dentry, 1422 ACL_TYPE_DEFAULT, fattr.cf_dacls); 1423 if (rc) 1424 ksmbd_debug(SMB, 1425 "Set posix acl(ACL_TYPE_DEFAULT) failed, rc : %d\n", 1426 rc); 1427 } 1428 } 1429 1430 inode_lock(inode); 1431 rc = notify_change(idmap, path->dentry, &newattrs, NULL); 1432 inode_unlock(inode); 1433 if (rc) 1434 goto out; 1435 1436 /* Check it only calling from SD BUFFER context */ 1437 if (type_check && !(le16_to_cpu(pntsd->type) & DACL_PRESENT)) 1438 goto out; 1439 1440 if (test_share_config_flag(tcon->share_conf, KSMBD_SHARE_FLAG_ACL_XATTR)) { 1441 /* Update WinACL in xattr */ 1442 ksmbd_vfs_remove_sd_xattrs(idmap, path); 1443 ksmbd_vfs_set_sd_xattr(conn, idmap, path, pntsd, ntsd_len, 1444 get_write); 1445 } 1446 1447 out: 1448 posix_acl_release(fattr.cf_acls); 1449 posix_acl_release(fattr.cf_dacls); 1450 return rc; 1451 } 1452 1453 void ksmbd_init_domain(u32 *sub_auth) 1454 { 1455 int i; 1456 1457 memcpy(&server_conf.domain_sid, &domain, sizeof(struct smb_sid)); 1458 for (i = 0; i < 3; ++i) 1459 server_conf.domain_sid.sub_auth[i + 1] = cpu_to_le32(sub_auth[i]); 1460 } 1461
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