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 (psid->num_subauth == 0) { 274 pr_err("%s: zero subauthorities!\n", __func__); 275 return -EIO; 276 } 277 278 if (sidtype == SIDOWNER) { 279 kuid_t uid; 280 uid_t id; 281 282 id = le32_to_cpu(psid->sub_auth[psid->num_subauth - 1]); 283 uid = KUIDT_INIT(id); 284 uid = from_vfsuid(idmap, &init_user_ns, VFSUIDT_INIT(uid)); 285 if (uid_valid(uid)) { 286 fattr->cf_uid = uid; 287 rc = 0; 288 } 289 } else { 290 kgid_t gid; 291 gid_t id; 292 293 id = le32_to_cpu(psid->sub_auth[psid->num_subauth - 1]); 294 gid = KGIDT_INIT(id); 295 gid = from_vfsgid(idmap, &init_user_ns, VFSGIDT_INIT(gid)); 296 if (gid_valid(gid)) { 297 fattr->cf_gid = gid; 298 rc = 0; 299 } 300 } 301 302 return rc; 303 } 304 305 void posix_state_to_acl(struct posix_acl_state *state, 306 struct posix_acl_entry *pace) 307 { 308 int i; 309 310 pace->e_tag = ACL_USER_OBJ; 311 pace->e_perm = state->owner.allow; 312 for (i = 0; i < state->users->n; i++) { 313 pace++; 314 pace->e_tag = ACL_USER; 315 pace->e_uid = state->users->aces[i].uid; 316 pace->e_perm = state->users->aces[i].perms.allow; 317 } 318 319 pace++; 320 pace->e_tag = ACL_GROUP_OBJ; 321 pace->e_perm = state->group.allow; 322 323 for (i = 0; i < state->groups->n; i++) { 324 pace++; 325 pace->e_tag = ACL_GROUP; 326 pace->e_gid = state->groups->aces[i].gid; 327 pace->e_perm = state->groups->aces[i].perms.allow; 328 } 329 330 if (state->users->n || state->groups->n) { 331 pace++; 332 pace->e_tag = ACL_MASK; 333 pace->e_perm = state->mask.allow; 334 } 335 336 pace++; 337 pace->e_tag = ACL_OTHER; 338 pace->e_perm = state->other.allow; 339 } 340 341 int init_acl_state(struct posix_acl_state *state, u16 cnt) 342 { 343 int alloc; 344 345 memset(state, 0, sizeof(struct posix_acl_state)); 346 /* 347 * In the worst case, each individual acl could be for a distinct 348 * named user or group, but we don't know which, so we allocate 349 * enough space for either: 350 */ 351 alloc = sizeof(struct posix_ace_state_array) 352 + cnt * sizeof(struct posix_user_ace_state); 353 state->users = kzalloc(alloc, KSMBD_DEFAULT_GFP); 354 if (!state->users) 355 return -ENOMEM; 356 state->groups = kzalloc(alloc, KSMBD_DEFAULT_GFP); 357 if (!state->groups) { 358 kfree(state->users); 359 return -ENOMEM; 360 } 361 return 0; 362 } 363 364 void free_acl_state(struct posix_acl_state *state) 365 { 366 kfree(state->users); 367 kfree(state->groups); 368 } 369 370 static void parse_dacl(struct mnt_idmap *idmap, 371 struct smb_acl *pdacl, char *end_of_acl, 372 struct smb_sid *pownersid, struct smb_sid *pgrpsid, 373 struct smb_fattr *fattr) 374 { 375 int i, ret; 376 u16 num_aces = 0; 377 unsigned int acl_size; 378 char *acl_base; 379 struct smb_ace **ppace; 380 struct posix_acl_entry *cf_pace, *cf_pdace; 381 struct posix_acl_state acl_state, default_acl_state; 382 umode_t mode = 0, acl_mode; 383 bool owner_found = false, group_found = false, others_found = false; 384 385 if (!pdacl) 386 return; 387 388 /* validate that we do not go past end of acl */ 389 if (end_of_acl < (char *)pdacl + sizeof(struct smb_acl) || 390 end_of_acl < (char *)pdacl + le16_to_cpu(pdacl->size)) { 391 pr_err("ACL too small to parse DACL\n"); 392 return; 393 } 394 395 ksmbd_debug(SMB, "DACL revision %d size %d num aces %d\n", 396 le16_to_cpu(pdacl->revision), le16_to_cpu(pdacl->size), 397 le16_to_cpu(pdacl->num_aces)); 398 399 acl_base = (char *)pdacl; 400 acl_size = sizeof(struct smb_acl); 401 402 num_aces = le16_to_cpu(pdacl->num_aces); 403 if (num_aces <= 0) 404 return; 405 406 if (num_aces > (le16_to_cpu(pdacl->size) - sizeof(struct smb_acl)) / 407 (offsetof(struct smb_ace, sid) + 408 offsetof(struct smb_sid, sub_auth) + sizeof(__le16))) 409 return; 410 411 ret = init_acl_state(&acl_state, num_aces); 412 if (ret) 413 return; 414 ret = init_acl_state(&default_acl_state, num_aces); 415 if (ret) { 416 free_acl_state(&acl_state); 417 return; 418 } 419 420 ppace = kmalloc_objs(struct smb_ace *, num_aces, KSMBD_DEFAULT_GFP); 421 if (!ppace) { 422 free_acl_state(&default_acl_state); 423 free_acl_state(&acl_state); 424 return; 425 } 426 427 /* 428 * reset rwx permissions for user/group/other. 429 * Also, if num_aces is 0 i.e. DACL has no ACEs, 430 * user/group/other have no permissions 431 */ 432 for (i = 0; i < num_aces; ++i) { 433 if (end_of_acl - acl_base < acl_size) 434 break; 435 436 ppace[i] = (struct smb_ace *)(acl_base + acl_size); 437 acl_base = (char *)ppace[i]; 438 acl_size = offsetof(struct smb_ace, sid) + 439 offsetof(struct smb_sid, sub_auth); 440 441 if (end_of_acl - acl_base < acl_size || 442 ppace[i]->sid.num_subauth == 0 || 443 ppace[i]->sid.num_subauth > SID_MAX_SUB_AUTHORITIES || 444 (end_of_acl - acl_base < 445 acl_size + sizeof(__le32) * ppace[i]->sid.num_subauth) || 446 (le16_to_cpu(ppace[i]->size) < 447 acl_size + sizeof(__le32) * ppace[i]->sid.num_subauth)) 448 break; 449 450 acl_size = le16_to_cpu(ppace[i]->size); 451 ppace[i]->access_req = 452 smb_map_generic_desired_access(ppace[i]->access_req); 453 454 if (ppace[i]->sid.num_subauth >= 3 && 455 !(compare_sids(&ppace[i]->sid, &sid_unix_NFS_mode))) { 456 fattr->cf_mode = 457 le32_to_cpu(ppace[i]->sid.sub_auth[2]); 458 break; 459 } else if (!compare_sids(&ppace[i]->sid, pownersid)) { 460 acl_mode = access_flags_to_mode(fattr, 461 ppace[i]->access_req, 462 ppace[i]->type); 463 acl_mode &= 0700; 464 465 if (!owner_found) { 466 mode &= ~(0700); 467 mode |= acl_mode; 468 } 469 owner_found = true; 470 } else if (!compare_sids(&ppace[i]->sid, pgrpsid) || 471 ppace[i]->sid.sub_auth[ppace[i]->sid.num_subauth - 1] == 472 DOMAIN_USER_RID_LE) { 473 acl_mode = access_flags_to_mode(fattr, 474 ppace[i]->access_req, 475 ppace[i]->type); 476 acl_mode &= 0070; 477 if (!group_found) { 478 mode &= ~(0070); 479 mode |= acl_mode; 480 } 481 group_found = true; 482 } else if (!compare_sids(&ppace[i]->sid, &sid_everyone)) { 483 acl_mode = access_flags_to_mode(fattr, 484 ppace[i]->access_req, 485 ppace[i]->type); 486 acl_mode &= 0007; 487 if (!others_found) { 488 mode &= ~(0007); 489 mode |= acl_mode; 490 } 491 others_found = true; 492 } else if (!compare_sids(&ppace[i]->sid, &creator_owner)) { 493 continue; 494 } else if (!compare_sids(&ppace[i]->sid, &creator_group)) { 495 continue; 496 } else if (!compare_sids(&ppace[i]->sid, &sid_authusers)) { 497 continue; 498 } else { 499 struct smb_fattr temp_fattr; 500 501 acl_mode = access_flags_to_mode(fattr, ppace[i]->access_req, 502 ppace[i]->type); 503 temp_fattr.cf_uid = INVALID_UID; 504 ret = sid_to_id(idmap, &ppace[i]->sid, SIDOWNER, &temp_fattr); 505 if (ret || uid_eq(temp_fattr.cf_uid, INVALID_UID)) { 506 pr_err("%s: Error %d mapping Owner SID to uid\n", 507 __func__, ret); 508 continue; 509 } 510 511 acl_state.owner.allow = ((acl_mode & 0700) >> 6) | 0004; 512 acl_state.users->aces[acl_state.users->n].uid = 513 temp_fattr.cf_uid; 514 acl_state.users->aces[acl_state.users->n++].perms.allow = 515 ((acl_mode & 0700) >> 6) | 0004; 516 default_acl_state.owner.allow = ((acl_mode & 0700) >> 6) | 0004; 517 default_acl_state.users->aces[default_acl_state.users->n].uid = 518 temp_fattr.cf_uid; 519 default_acl_state.users->aces[default_acl_state.users->n++].perms.allow = 520 ((acl_mode & 0700) >> 6) | 0004; 521 } 522 } 523 kfree(ppace); 524 525 if (owner_found) { 526 /* The owner must be set to at least read-only. */ 527 acl_state.owner.allow = ((mode & 0700) >> 6) | 0004; 528 acl_state.users->aces[acl_state.users->n].uid = fattr->cf_uid; 529 acl_state.users->aces[acl_state.users->n++].perms.allow = 530 ((mode & 0700) >> 6) | 0004; 531 default_acl_state.owner.allow = ((mode & 0700) >> 6) | 0004; 532 default_acl_state.users->aces[default_acl_state.users->n].uid = 533 fattr->cf_uid; 534 default_acl_state.users->aces[default_acl_state.users->n++].perms.allow = 535 ((mode & 0700) >> 6) | 0004; 536 } 537 538 if (group_found) { 539 acl_state.group.allow = (mode & 0070) >> 3; 540 acl_state.groups->aces[acl_state.groups->n].gid = 541 fattr->cf_gid; 542 acl_state.groups->aces[acl_state.groups->n++].perms.allow = 543 (mode & 0070) >> 3; 544 default_acl_state.group.allow = (mode & 0070) >> 3; 545 default_acl_state.groups->aces[default_acl_state.groups->n].gid = 546 fattr->cf_gid; 547 default_acl_state.groups->aces[default_acl_state.groups->n++].perms.allow = 548 (mode & 0070) >> 3; 549 } 550 551 if (others_found) { 552 fattr->cf_mode &= ~(0007); 553 fattr->cf_mode |= mode & 0007; 554 555 acl_state.other.allow = mode & 0007; 556 default_acl_state.other.allow = mode & 0007; 557 } 558 559 if (acl_state.users->n || acl_state.groups->n) { 560 acl_state.mask.allow = 0x07; 561 562 if (IS_ENABLED(CONFIG_FS_POSIX_ACL)) { 563 fattr->cf_acls = 564 posix_acl_alloc(acl_state.users->n + 565 acl_state.groups->n + 4, KSMBD_DEFAULT_GFP); 566 if (fattr->cf_acls) { 567 cf_pace = fattr->cf_acls->a_entries; 568 posix_state_to_acl(&acl_state, cf_pace); 569 } 570 } 571 } 572 573 if (default_acl_state.users->n || default_acl_state.groups->n) { 574 default_acl_state.mask.allow = 0x07; 575 576 if (IS_ENABLED(CONFIG_FS_POSIX_ACL)) { 577 fattr->cf_dacls = 578 posix_acl_alloc(default_acl_state.users->n + 579 default_acl_state.groups->n + 4, KSMBD_DEFAULT_GFP); 580 if (fattr->cf_dacls) { 581 cf_pdace = fattr->cf_dacls->a_entries; 582 posix_state_to_acl(&default_acl_state, cf_pdace); 583 } 584 } 585 } 586 free_acl_state(&acl_state); 587 free_acl_state(&default_acl_state); 588 } 589 590 static void set_posix_acl_entries_dacl(struct mnt_idmap *idmap, 591 struct smb_ace *pndace, 592 struct smb_fattr *fattr, u16 *num_aces, 593 u16 *size, u32 nt_aces_num) 594 { 595 struct posix_acl_entry *pace; 596 struct smb_sid *sid; 597 struct smb_ace *ntace; 598 int i, j; 599 u16 ace_sz; 600 601 if (!fattr->cf_acls) 602 goto posix_default_acl; 603 604 pace = fattr->cf_acls->a_entries; 605 for (i = 0; i < fattr->cf_acls->a_count; i++, pace++) { 606 int flags = 0; 607 608 sid = kmalloc_obj(struct smb_sid, KSMBD_DEFAULT_GFP); 609 if (!sid) 610 break; 611 612 if (pace->e_tag == ACL_USER) { 613 uid_t uid; 614 unsigned int sid_type = SIDOWNER; 615 616 uid = posix_acl_uid_translate(idmap, pace); 617 if (!uid) 618 sid_type = SIDUNIX_USER; 619 id_to_sid(uid, sid_type, sid); 620 } else if (pace->e_tag == ACL_GROUP) { 621 gid_t gid; 622 623 gid = posix_acl_gid_translate(idmap, pace); 624 id_to_sid(gid, SIDUNIX_GROUP, sid); 625 } else if (pace->e_tag == ACL_OTHER && !nt_aces_num) { 626 smb_copy_sid(sid, &sid_everyone); 627 } else { 628 kfree(sid); 629 continue; 630 } 631 ntace = pndace; 632 for (j = 0; j < nt_aces_num; j++) { 633 if (ntace->sid.sub_auth[ntace->sid.num_subauth - 1] == 634 sid->sub_auth[sid->num_subauth - 1]) 635 goto pass_same_sid; 636 ntace = (struct smb_ace *)((char *)ntace + 637 le16_to_cpu(ntace->size)); 638 } 639 640 if (S_ISDIR(fattr->cf_mode) && pace->e_tag == ACL_OTHER) 641 flags = 0x03; 642 643 ntace = (struct smb_ace *)((char *)pndace + *size); 644 ace_sz = fill_ace_for_sid(ntace, sid, ACCESS_ALLOWED, flags, 645 pace->e_perm, 0777); 646 if (check_add_overflow(*size, ace_sz, size)) 647 break; 648 (*num_aces)++; 649 if (pace->e_tag == ACL_USER) 650 ntace->access_req |= 651 FILE_DELETE_LE | FILE_DELETE_CHILD_LE; 652 653 if (S_ISDIR(fattr->cf_mode) && 654 (pace->e_tag == ACL_USER || pace->e_tag == ACL_GROUP)) { 655 ntace = (struct smb_ace *)((char *)pndace + *size); 656 ace_sz = fill_ace_for_sid(ntace, sid, ACCESS_ALLOWED, 657 0x03, pace->e_perm, 0777); 658 if (check_add_overflow(*size, ace_sz, size)) 659 break; 660 (*num_aces)++; 661 if (pace->e_tag == ACL_USER) 662 ntace->access_req |= 663 FILE_DELETE_LE | FILE_DELETE_CHILD_LE; 664 } 665 666 pass_same_sid: 667 kfree(sid); 668 } 669 670 if (nt_aces_num) 671 return; 672 673 posix_default_acl: 674 if (!fattr->cf_dacls) 675 return; 676 677 pace = fattr->cf_dacls->a_entries; 678 for (i = 0; i < fattr->cf_dacls->a_count; i++, pace++) { 679 sid = kmalloc_obj(struct smb_sid, KSMBD_DEFAULT_GFP); 680 if (!sid) 681 break; 682 683 if (pace->e_tag == ACL_USER) { 684 uid_t uid; 685 686 uid = posix_acl_uid_translate(idmap, pace); 687 id_to_sid(uid, SIDCREATOR_OWNER, sid); 688 } else if (pace->e_tag == ACL_GROUP) { 689 gid_t gid; 690 691 gid = posix_acl_gid_translate(idmap, pace); 692 id_to_sid(gid, SIDCREATOR_GROUP, sid); 693 } else { 694 kfree(sid); 695 continue; 696 } 697 698 ntace = (struct smb_ace *)((char *)pndace + *size); 699 ace_sz = fill_ace_for_sid(ntace, sid, ACCESS_ALLOWED, 0x0b, 700 pace->e_perm, 0777); 701 if (check_add_overflow(*size, ace_sz, size)) 702 break; 703 (*num_aces)++; 704 if (pace->e_tag == ACL_USER) 705 ntace->access_req |= 706 FILE_DELETE_LE | FILE_DELETE_CHILD_LE; 707 kfree(sid); 708 } 709 } 710 711 static void set_ntacl_dacl(struct mnt_idmap *idmap, 712 struct smb_acl *pndacl, 713 struct smb_acl *nt_dacl, 714 unsigned int aces_size, 715 const struct smb_sid *pownersid, 716 const struct smb_sid *pgrpsid, 717 struct smb_fattr *fattr) 718 { 719 struct smb_ace *ntace, *pndace; 720 u16 nt_num_aces = le16_to_cpu(nt_dacl->num_aces), num_aces = 0; 721 unsigned short size = 0; 722 int i; 723 724 pndace = (struct smb_ace *)((char *)pndacl + sizeof(struct smb_acl)); 725 if (nt_num_aces) { 726 ntace = (struct smb_ace *)((char *)nt_dacl + sizeof(struct smb_acl)); 727 for (i = 0; i < nt_num_aces; i++) { 728 unsigned short nt_ace_size; 729 730 if (offsetof(struct smb_ace, access_req) > aces_size) 731 break; 732 733 nt_ace_size = le16_to_cpu(ntace->size); 734 if (nt_ace_size > aces_size) 735 break; 736 737 memcpy((char *)pndace + size, ntace, nt_ace_size); 738 if (check_add_overflow(size, nt_ace_size, &size)) 739 break; 740 aces_size -= nt_ace_size; 741 ntace = (struct smb_ace *)((char *)ntace + nt_ace_size); 742 num_aces++; 743 } 744 } 745 746 set_posix_acl_entries_dacl(idmap, pndace, fattr, 747 &num_aces, &size, nt_num_aces); 748 pndacl->num_aces = cpu_to_le16(num_aces); 749 pndacl->size = cpu_to_le16(le16_to_cpu(pndacl->size) + size); 750 } 751 752 static void set_mode_dacl(struct mnt_idmap *idmap, 753 struct smb_acl *pndacl, struct smb_fattr *fattr) 754 { 755 struct smb_ace *pace, *pndace; 756 u16 num_aces = 0; 757 u16 size = 0, ace_size = 0; 758 uid_t uid; 759 const struct smb_sid *sid; 760 761 pace = pndace = (struct smb_ace *)((char *)pndacl + sizeof(struct smb_acl)); 762 763 if (fattr->cf_acls) { 764 set_posix_acl_entries_dacl(idmap, pndace, fattr, 765 &num_aces, &size, num_aces); 766 goto out; 767 } 768 769 /* owner RID */ 770 uid = from_kuid(&init_user_ns, fattr->cf_uid); 771 if (uid) 772 sid = &server_conf.domain_sid; 773 else 774 sid = &sid_unix_users; 775 ace_size = fill_ace_for_sid(pace, sid, ACCESS_ALLOWED, 0, 776 fattr->cf_mode, 0700); 777 pace->sid.sub_auth[pace->sid.num_subauth++] = cpu_to_le32(uid); 778 pace->size = cpu_to_le16(ace_size + 4); 779 size += le16_to_cpu(pace->size); 780 pace = (struct smb_ace *)((char *)pndace + size); 781 782 /* Group RID */ 783 ace_size = fill_ace_for_sid(pace, &sid_unix_groups, 784 ACCESS_ALLOWED, 0, fattr->cf_mode, 0070); 785 pace->sid.sub_auth[pace->sid.num_subauth++] = 786 cpu_to_le32(from_kgid(&init_user_ns, fattr->cf_gid)); 787 pace->size = cpu_to_le16(ace_size + 4); 788 size += le16_to_cpu(pace->size); 789 pace = (struct smb_ace *)((char *)pndace + size); 790 num_aces = 3; 791 792 if (S_ISDIR(fattr->cf_mode)) { 793 pace = (struct smb_ace *)((char *)pndace + size); 794 795 /* creator owner */ 796 size += fill_ace_for_sid(pace, &creator_owner, ACCESS_ALLOWED, 797 0x0b, fattr->cf_mode, 0700); 798 pace = (struct smb_ace *)((char *)pndace + size); 799 800 /* creator group */ 801 size += fill_ace_for_sid(pace, &creator_group, ACCESS_ALLOWED, 802 0x0b, fattr->cf_mode, 0070); 803 pace = (struct smb_ace *)((char *)pndace + size); 804 num_aces = 5; 805 } 806 807 /* other */ 808 size += fill_ace_for_sid(pace, &sid_everyone, ACCESS_ALLOWED, 0, 809 fattr->cf_mode, 0007); 810 811 out: 812 pndacl->num_aces = cpu_to_le16(num_aces); 813 pndacl->size = cpu_to_le16(le16_to_cpu(pndacl->size) + size); 814 } 815 816 static int parse_sid(struct smb_sid *psid, char *end_of_acl) 817 { 818 /* 819 * validate that we do not go past end of ACL - sid must be at least 8 820 * bytes long (assuming no sub-auths - e.g. the null SID 821 */ 822 if (end_of_acl < (char *)psid + 8) { 823 pr_err("ACL too small to parse SID %p\n", psid); 824 return -EINVAL; 825 } 826 827 if (!psid->num_subauth) 828 return 0; 829 830 if (psid->num_subauth > SID_MAX_SUB_AUTHORITIES || 831 end_of_acl < (char *)psid + 8 + sizeof(__le32) * psid->num_subauth) 832 return -EINVAL; 833 834 return 0; 835 } 836 837 /* Convert CIFS ACL to POSIX form */ 838 int parse_sec_desc(struct mnt_idmap *idmap, struct smb_ntsd *pntsd, 839 int acl_len, struct smb_fattr *fattr) 840 { 841 int rc = 0; 842 struct smb_sid *owner_sid_ptr, *group_sid_ptr; 843 struct smb_acl *dacl_ptr; /* no need for SACL ptr */ 844 char *end_of_acl = ((char *)pntsd) + acl_len; 845 __u32 dacloffset; 846 int pntsd_type; 847 848 if (!pntsd) 849 return -EIO; 850 851 if (acl_len < sizeof(struct smb_ntsd)) 852 return -EINVAL; 853 854 owner_sid_ptr = (struct smb_sid *)((char *)pntsd + 855 le32_to_cpu(pntsd->osidoffset)); 856 group_sid_ptr = (struct smb_sid *)((char *)pntsd + 857 le32_to_cpu(pntsd->gsidoffset)); 858 dacloffset = le32_to_cpu(pntsd->dacloffset); 859 dacl_ptr = (struct smb_acl *)((char *)pntsd + dacloffset); 860 ksmbd_debug(SMB, 861 "revision %d type 0x%x ooffset 0x%x goffset 0x%x sacloffset 0x%x dacloffset 0x%x\n", 862 pntsd->revision, pntsd->type, le32_to_cpu(pntsd->osidoffset), 863 le32_to_cpu(pntsd->gsidoffset), 864 le32_to_cpu(pntsd->sacloffset), dacloffset); 865 866 pntsd_type = le16_to_cpu(pntsd->type); 867 if (!(pntsd_type & DACL_PRESENT)) { 868 ksmbd_debug(SMB, "DACL_PRESENT in DACL type is not set\n"); 869 return rc; 870 } 871 872 pntsd->type = cpu_to_le16(DACL_PRESENT); 873 874 if (pntsd->osidoffset) { 875 if (le32_to_cpu(pntsd->osidoffset) < sizeof(struct smb_ntsd)) 876 return -EINVAL; 877 878 rc = parse_sid(owner_sid_ptr, end_of_acl); 879 if (rc) { 880 pr_err("%s: Error %d parsing Owner SID\n", __func__, rc); 881 return rc; 882 } 883 884 rc = sid_to_id(idmap, owner_sid_ptr, SIDOWNER, fattr); 885 if (rc) { 886 pr_err("%s: Error %d mapping Owner SID to uid\n", 887 __func__, rc); 888 owner_sid_ptr = NULL; 889 } 890 } 891 892 if (pntsd->gsidoffset) { 893 if (le32_to_cpu(pntsd->gsidoffset) < sizeof(struct smb_ntsd)) 894 return -EINVAL; 895 896 rc = parse_sid(group_sid_ptr, end_of_acl); 897 if (rc) { 898 pr_err("%s: Error %d mapping Owner SID to gid\n", 899 __func__, rc); 900 return rc; 901 } 902 rc = sid_to_id(idmap, group_sid_ptr, SIDUNIX_GROUP, fattr); 903 if (rc) { 904 pr_err("%s: Error %d mapping Group SID to gid\n", 905 __func__, rc); 906 group_sid_ptr = NULL; 907 } 908 } 909 910 if ((pntsd_type & (DACL_AUTO_INHERITED | DACL_AUTO_INHERIT_REQ)) == 911 (DACL_AUTO_INHERITED | DACL_AUTO_INHERIT_REQ)) 912 pntsd->type |= cpu_to_le16(DACL_AUTO_INHERITED); 913 if (pntsd_type & DACL_PROTECTED) 914 pntsd->type |= cpu_to_le16(DACL_PROTECTED); 915 916 if (dacloffset) { 917 if (dacloffset < sizeof(struct smb_ntsd)) 918 return -EINVAL; 919 920 parse_dacl(idmap, dacl_ptr, end_of_acl, 921 owner_sid_ptr, group_sid_ptr, fattr); 922 } 923 924 return 0; 925 } 926 927 size_t smb_acl_sec_desc_scratch_len(struct smb_fattr *fattr, 928 struct smb_ntsd *ppntsd, int ppntsd_size, int addition_info) 929 { 930 size_t len = sizeof(struct smb_ntsd); 931 size_t tmp; 932 933 if (addition_info & OWNER_SECINFO) 934 len += sizeof(struct smb_sid); 935 if (addition_info & GROUP_SECINFO) 936 len += sizeof(struct smb_sid); 937 if (!(addition_info & DACL_SECINFO)) 938 return len; 939 940 len += sizeof(struct smb_acl); 941 if (ppntsd && ppntsd_size > 0) { 942 unsigned int dacl_offset = le32_to_cpu(ppntsd->dacloffset); 943 944 if (dacl_offset < ppntsd_size && 945 check_add_overflow(len, ppntsd_size - dacl_offset, &len)) 946 return 0; 947 } 948 949 if (fattr->cf_acls) { 950 if (check_mul_overflow((size_t)fattr->cf_acls->a_count, 951 2 * sizeof(struct smb_ace), &tmp) || 952 check_add_overflow(len, tmp, &len)) 953 return 0; 954 } else { 955 /* default/minimum DACL */ 956 if (check_add_overflow(len, 5 * sizeof(struct smb_ace), &len)) 957 return 0; 958 } 959 960 if (fattr->cf_dacls) { 961 if (check_mul_overflow((size_t)fattr->cf_dacls->a_count, 962 sizeof(struct smb_ace), &tmp) || 963 check_add_overflow(len, tmp, &len)) 964 return 0; 965 } 966 967 return len; 968 } 969 970 /* Convert permission bits from mode to equivalent CIFS ACL */ 971 int build_sec_desc(struct mnt_idmap *idmap, 972 struct smb_ntsd *pntsd, struct smb_ntsd *ppntsd, 973 int ppntsd_size, int addition_info, __u32 *secdesclen, 974 struct smb_fattr *fattr) 975 { 976 int rc = 0; 977 __u32 offset; 978 struct smb_sid *owner_sid_ptr, *group_sid_ptr; 979 struct smb_sid *nowner_sid_ptr, *ngroup_sid_ptr; 980 struct smb_acl *dacl_ptr = NULL; /* no need for SACL ptr */ 981 uid_t uid; 982 gid_t gid; 983 unsigned int sid_type = SIDOWNER; 984 985 nowner_sid_ptr = kmalloc_obj(struct smb_sid, KSMBD_DEFAULT_GFP); 986 if (!nowner_sid_ptr) 987 return -ENOMEM; 988 989 uid = from_kuid(&init_user_ns, fattr->cf_uid); 990 if (!uid) 991 sid_type = SIDUNIX_USER; 992 id_to_sid(uid, sid_type, nowner_sid_ptr); 993 994 ngroup_sid_ptr = kmalloc_obj(struct smb_sid, KSMBD_DEFAULT_GFP); 995 if (!ngroup_sid_ptr) { 996 kfree(nowner_sid_ptr); 997 return -ENOMEM; 998 } 999 1000 gid = from_kgid(&init_user_ns, fattr->cf_gid); 1001 id_to_sid(gid, SIDUNIX_GROUP, ngroup_sid_ptr); 1002 1003 offset = sizeof(struct smb_ntsd); 1004 pntsd->sacloffset = 0; 1005 pntsd->revision = cpu_to_le16(1); 1006 pntsd->type = cpu_to_le16(SELF_RELATIVE); 1007 if (ppntsd) 1008 pntsd->type |= ppntsd->type; 1009 1010 if (addition_info & OWNER_SECINFO) { 1011 pntsd->osidoffset = cpu_to_le32(offset); 1012 owner_sid_ptr = (struct smb_sid *)((char *)pntsd + offset); 1013 smb_copy_sid(owner_sid_ptr, nowner_sid_ptr); 1014 offset += 1 + 1 + 6 + (nowner_sid_ptr->num_subauth * 4); 1015 } 1016 1017 if (addition_info & GROUP_SECINFO) { 1018 pntsd->gsidoffset = cpu_to_le32(offset); 1019 group_sid_ptr = (struct smb_sid *)((char *)pntsd + offset); 1020 smb_copy_sid(group_sid_ptr, ngroup_sid_ptr); 1021 offset += 1 + 1 + 6 + (ngroup_sid_ptr->num_subauth * 4); 1022 } 1023 1024 if (addition_info & DACL_SECINFO) { 1025 pntsd->type |= cpu_to_le16(DACL_PRESENT); 1026 dacl_ptr = (struct smb_acl *)((char *)pntsd + offset); 1027 dacl_ptr->revision = cpu_to_le16(2); 1028 dacl_ptr->size = cpu_to_le16(sizeof(struct smb_acl)); 1029 dacl_ptr->num_aces = 0; 1030 1031 if (!ppntsd) { 1032 set_mode_dacl(idmap, dacl_ptr, fattr); 1033 } else { 1034 struct smb_acl *ppdacl_ptr; 1035 unsigned int dacl_offset = le32_to_cpu(ppntsd->dacloffset); 1036 int ppdacl_size, ntacl_size = ppntsd_size - dacl_offset; 1037 1038 if (!dacl_offset || 1039 (dacl_offset + sizeof(struct smb_acl) > ppntsd_size)) 1040 goto out; 1041 1042 ppdacl_ptr = (struct smb_acl *)((char *)ppntsd + dacl_offset); 1043 ppdacl_size = le16_to_cpu(ppdacl_ptr->size); 1044 if (ppdacl_size > ntacl_size || 1045 ppdacl_size < sizeof(struct smb_acl)) 1046 goto out; 1047 1048 set_ntacl_dacl(idmap, dacl_ptr, ppdacl_ptr, 1049 ntacl_size - sizeof(struct smb_acl), 1050 nowner_sid_ptr, ngroup_sid_ptr, 1051 fattr); 1052 } 1053 pntsd->dacloffset = cpu_to_le32(offset); 1054 offset += le16_to_cpu(dacl_ptr->size); 1055 } 1056 1057 out: 1058 kfree(nowner_sid_ptr); 1059 kfree(ngroup_sid_ptr); 1060 *secdesclen = offset; 1061 return rc; 1062 } 1063 1064 static void smb_set_ace(struct smb_ace *ace, const struct smb_sid *sid, u8 type, 1065 u8 flags, __le32 access_req) 1066 { 1067 ace->type = type; 1068 ace->flags = flags; 1069 ace->access_req = access_req; 1070 smb_copy_sid(&ace->sid, sid); 1071 ace->size = cpu_to_le16(1 + 1 + 2 + 4 + 1 + 1 + 6 + 1072 (ace->sid.num_subauth * 4)); 1073 } 1074 1075 static int smb_append_inherited_ace(struct smb_ace **ace, int *nt_size, 1076 u16 *ace_cnt, const struct smb_sid *sid, 1077 u8 type, u8 flags, __le32 access_req) 1078 { 1079 int ace_size; 1080 1081 smb_set_ace(*ace, sid, type, flags, access_req); 1082 ace_size = le16_to_cpu((*ace)->size); 1083 /* pdacl->size is __le16 and includes struct smb_acl. */ 1084 if (check_add_overflow(*nt_size, ace_size, nt_size) || 1085 *nt_size > U16_MAX - (int)sizeof(struct smb_acl)) 1086 return -EINVAL; 1087 1088 (*ace_cnt)++; 1089 *ace = (struct smb_ace *)((char *)*ace + ace_size); 1090 return 0; 1091 } 1092 1093 int smb_inherit_dacl(struct ksmbd_conn *conn, 1094 const struct path *path, 1095 unsigned int uid, unsigned int gid) 1096 { 1097 const struct smb_sid *psid, *creator = NULL; 1098 struct smb_ace *parent_aces, *aces; 1099 struct smb_acl *parent_pdacl; 1100 struct smb_ntsd *parent_pntsd = NULL; 1101 struct smb_sid owner_sid, group_sid; 1102 struct dentry *parent = path->dentry->d_parent; 1103 struct mnt_idmap *idmap = mnt_idmap(path->mnt); 1104 int inherited_flags = 0, flags = 0, i, nt_size = 0, pdacl_size; 1105 int rc = 0, pntsd_type, pntsd_size, acl_len, aces_size; 1106 unsigned int dacloffset; 1107 size_t dacl_struct_end; 1108 u16 num_aces, ace_cnt = 0; 1109 char *aces_base; 1110 bool is_dir = S_ISDIR(d_inode(path->dentry)->i_mode); 1111 1112 pntsd_size = ksmbd_vfs_get_sd_xattr(conn, idmap, 1113 parent, &parent_pntsd); 1114 if (pntsd_size <= 0) 1115 return -ENOENT; 1116 1117 dacloffset = le32_to_cpu(parent_pntsd->dacloffset); 1118 if (!dacloffset || 1119 check_add_overflow(dacloffset, sizeof(struct smb_acl), &dacl_struct_end) || 1120 dacl_struct_end > (size_t)pntsd_size) { 1121 rc = -EINVAL; 1122 goto free_parent_pntsd; 1123 } 1124 1125 parent_pdacl = (struct smb_acl *)((char *)parent_pntsd + dacloffset); 1126 acl_len = pntsd_size - dacloffset; 1127 num_aces = le16_to_cpu(parent_pdacl->num_aces); 1128 pntsd_type = le16_to_cpu(parent_pntsd->type); 1129 pdacl_size = le16_to_cpu(parent_pdacl->size); 1130 1131 if (pdacl_size > acl_len || pdacl_size < sizeof(struct smb_acl)) { 1132 rc = -EINVAL; 1133 goto free_parent_pntsd; 1134 } 1135 1136 aces_size = pdacl_size - sizeof(struct smb_acl); 1137 1138 /* 1139 * Validate num_aces against the DACL payload before allocating. 1140 * Each ACE must be at least as large as its fixed-size header 1141 * (up to the SID base), so num_aces cannot exceed the payload 1142 * divided by the minimum ACE size. This mirrors the existing 1143 * check in parse_dacl(). 1144 */ 1145 if (num_aces > aces_size / (offsetof(struct smb_ace, sid) + 1146 offsetof(struct smb_sid, sub_auth) + 1147 sizeof(__le16))) { 1148 rc = -EINVAL; 1149 goto free_parent_pntsd; 1150 } 1151 1152 aces_base = kmalloc_array(num_aces * 2, sizeof(struct smb_ace), 1153 KSMBD_DEFAULT_GFP); 1154 if (!aces_base) { 1155 rc = -ENOMEM; 1156 goto free_parent_pntsd; 1157 } 1158 1159 aces = (struct smb_ace *)aces_base; 1160 parent_aces = (struct smb_ace *)((char *)parent_pdacl + 1161 sizeof(struct smb_acl)); 1162 1163 if (pntsd_type & DACL_AUTO_INHERITED) 1164 inherited_flags = INHERITED_ACE; 1165 1166 for (i = 0; i < num_aces; i++) { 1167 int pace_size; 1168 1169 if (aces_size < offsetof(struct smb_ace, sid) + 1170 CIFS_SID_BASE_SIZE) 1171 break; 1172 1173 pace_size = le16_to_cpu(parent_aces->size); 1174 if (pace_size > aces_size || 1175 pace_size < offsetof(struct smb_ace, sid) + 1176 CIFS_SID_BASE_SIZE) 1177 break; 1178 1179 if (parent_aces->sid.num_subauth > SID_MAX_SUB_AUTHORITIES || 1180 pace_size < offsetof(struct smb_ace, sid) + 1181 CIFS_SID_BASE_SIZE + 1182 sizeof(__le32) * parent_aces->sid.num_subauth) 1183 break; 1184 1185 aces_size -= pace_size; 1186 1187 flags = parent_aces->flags; 1188 if (!smb_inherit_flags(flags, is_dir)) 1189 goto pass; 1190 if (is_dir) { 1191 flags &= ~(INHERIT_ONLY_ACE | INHERITED_ACE); 1192 if (!(flags & CONTAINER_INHERIT_ACE)) 1193 flags |= INHERIT_ONLY_ACE; 1194 if (flags & NO_PROPAGATE_INHERIT_ACE) 1195 flags = 0; 1196 } else { 1197 flags = 0; 1198 } 1199 1200 if (!compare_sids(&creator_owner, &parent_aces->sid)) { 1201 creator = &creator_owner; 1202 id_to_sid(uid, SIDOWNER, &owner_sid); 1203 psid = &owner_sid; 1204 } else if (!compare_sids(&creator_group, &parent_aces->sid)) { 1205 creator = &creator_group; 1206 id_to_sid(gid, SIDUNIX_GROUP, &group_sid); 1207 psid = &group_sid; 1208 } else { 1209 creator = NULL; 1210 psid = &parent_aces->sid; 1211 } 1212 1213 if (is_dir && creator && flags & CONTAINER_INHERIT_ACE) { 1214 rc = smb_append_inherited_ace(&aces, &nt_size, &ace_cnt, 1215 psid, parent_aces->type, 1216 inherited_flags, 1217 parent_aces->access_req); 1218 if (rc) 1219 goto free_aces_base; 1220 flags |= INHERIT_ONLY_ACE; 1221 psid = creator; 1222 } else if (is_dir && !(parent_aces->flags & NO_PROPAGATE_INHERIT_ACE)) { 1223 psid = &parent_aces->sid; 1224 } 1225 1226 rc = smb_append_inherited_ace(&aces, &nt_size, &ace_cnt, psid, 1227 parent_aces->type, 1228 flags | inherited_flags, 1229 parent_aces->access_req); 1230 if (rc) 1231 goto free_aces_base; 1232 pass: 1233 parent_aces = (struct smb_ace *)((char *)parent_aces + pace_size); 1234 } 1235 1236 if (nt_size > 0) { 1237 struct smb_ntsd *pntsd; 1238 struct smb_acl *pdacl; 1239 struct smb_sid *powner_sid = NULL, *pgroup_sid = NULL; 1240 int powner_sid_size = 0, pgroup_sid_size = 0, pntsd_size; 1241 size_t pntsd_alloc_size; 1242 1243 if (parent_pntsd->osidoffset) { 1244 powner_sid = (struct smb_sid *)((char *)parent_pntsd + 1245 le32_to_cpu(parent_pntsd->osidoffset)); 1246 powner_sid_size = 1 + 1 + 6 + (powner_sid->num_subauth * 4); 1247 } 1248 if (parent_pntsd->gsidoffset) { 1249 pgroup_sid = (struct smb_sid *)((char *)parent_pntsd + 1250 le32_to_cpu(parent_pntsd->gsidoffset)); 1251 pgroup_sid_size = 1 + 1 + 6 + (pgroup_sid->num_subauth * 4); 1252 } 1253 1254 if (check_add_overflow(sizeof(struct smb_ntsd), 1255 (size_t)powner_sid_size, 1256 &pntsd_alloc_size) || 1257 check_add_overflow(pntsd_alloc_size, 1258 (size_t)pgroup_sid_size, 1259 &pntsd_alloc_size) || 1260 check_add_overflow(pntsd_alloc_size, sizeof(struct smb_acl), 1261 &pntsd_alloc_size) || 1262 check_add_overflow(pntsd_alloc_size, (size_t)nt_size, 1263 &pntsd_alloc_size)) { 1264 rc = -EINVAL; 1265 goto free_aces_base; 1266 } 1267 1268 pntsd = kzalloc(pntsd_alloc_size, KSMBD_DEFAULT_GFP); 1269 if (!pntsd) { 1270 rc = -ENOMEM; 1271 goto free_aces_base; 1272 } 1273 1274 pntsd->revision = cpu_to_le16(1); 1275 pntsd->type = cpu_to_le16(SELF_RELATIVE | DACL_PRESENT); 1276 if (le16_to_cpu(parent_pntsd->type) & DACL_AUTO_INHERITED) 1277 pntsd->type |= cpu_to_le16(DACL_AUTO_INHERITED); 1278 pntsd_size = sizeof(struct smb_ntsd); 1279 pntsd->osidoffset = parent_pntsd->osidoffset; 1280 pntsd->gsidoffset = parent_pntsd->gsidoffset; 1281 pntsd->dacloffset = parent_pntsd->dacloffset; 1282 1283 if ((u64)le32_to_cpu(pntsd->osidoffset) + powner_sid_size > 1284 pntsd_alloc_size) { 1285 rc = -EINVAL; 1286 kfree(pntsd); 1287 goto free_aces_base; 1288 } 1289 1290 if ((u64)le32_to_cpu(pntsd->gsidoffset) + pgroup_sid_size > 1291 pntsd_alloc_size) { 1292 rc = -EINVAL; 1293 kfree(pntsd); 1294 goto free_aces_base; 1295 } 1296 1297 if ((u64)le32_to_cpu(pntsd->dacloffset) + sizeof(struct smb_acl) + nt_size > 1298 pntsd_alloc_size) { 1299 rc = -EINVAL; 1300 kfree(pntsd); 1301 goto free_aces_base; 1302 } 1303 1304 if (pntsd->osidoffset) { 1305 struct smb_sid *owner_sid = (struct smb_sid *)((char *)pntsd + 1306 le32_to_cpu(pntsd->osidoffset)); 1307 memcpy(owner_sid, powner_sid, powner_sid_size); 1308 pntsd_size += powner_sid_size; 1309 } 1310 1311 if (pntsd->gsidoffset) { 1312 struct smb_sid *group_sid = (struct smb_sid *)((char *)pntsd + 1313 le32_to_cpu(pntsd->gsidoffset)); 1314 memcpy(group_sid, pgroup_sid, pgroup_sid_size); 1315 pntsd_size += pgroup_sid_size; 1316 } 1317 1318 if (pntsd->dacloffset) { 1319 struct smb_ace *pace; 1320 1321 pdacl = (struct smb_acl *)((char *)pntsd + le32_to_cpu(pntsd->dacloffset)); 1322 pdacl->revision = cpu_to_le16(2); 1323 pdacl->size = cpu_to_le16(sizeof(struct smb_acl) + nt_size); 1324 pdacl->num_aces = cpu_to_le16(ace_cnt); 1325 pace = (struct smb_ace *)((char *)pdacl + sizeof(struct smb_acl)); 1326 memcpy(pace, aces_base, nt_size); 1327 pntsd_size += sizeof(struct smb_acl) + nt_size; 1328 } 1329 1330 ksmbd_vfs_set_sd_xattr(conn, idmap, path, pntsd, pntsd_size, false); 1331 kfree(pntsd); 1332 } 1333 1334 free_aces_base: 1335 kfree(aces_base); 1336 free_parent_pntsd: 1337 kfree(parent_pntsd); 1338 return rc; 1339 } 1340 1341 bool smb_inherit_flags(int flags, bool is_dir) 1342 { 1343 if (!is_dir) 1344 return (flags & OBJECT_INHERIT_ACE) != 0; 1345 1346 if (flags & OBJECT_INHERIT_ACE && !(flags & NO_PROPAGATE_INHERIT_ACE)) 1347 return true; 1348 1349 if (flags & CONTAINER_INHERIT_ACE) 1350 return true; 1351 return false; 1352 } 1353 1354 int smb_check_perm_dacl(struct ksmbd_conn *conn, const struct path *path, 1355 __le32 *pdaccess, int uid) 1356 { 1357 struct mnt_idmap *idmap = mnt_idmap(path->mnt); 1358 struct smb_ntsd *pntsd = NULL; 1359 struct smb_acl *pdacl; 1360 struct posix_acl *posix_acls; 1361 int rc = 0, pntsd_size, acl_size, aces_size, pdacl_size; 1362 unsigned int dacl_offset; 1363 size_t dacl_struct_end; 1364 struct smb_sid sid; 1365 int granted = le32_to_cpu(*pdaccess & ~FILE_MAXIMAL_ACCESS_LE); 1366 struct smb_ace *ace; 1367 int i, found = 0; 1368 unsigned int access_bits = 0; 1369 struct smb_ace *others_ace = NULL; 1370 struct posix_acl_entry *pa_entry; 1371 unsigned int sid_type = SIDOWNER; 1372 unsigned short ace_size; 1373 1374 ksmbd_debug(SMB, "check permission using windows acl\n"); 1375 pntsd_size = ksmbd_vfs_get_sd_xattr(conn, idmap, 1376 path->dentry, &pntsd); 1377 if (pntsd_size <= 0 || !pntsd) 1378 goto err_out; 1379 1380 dacl_offset = le32_to_cpu(pntsd->dacloffset); 1381 if (!dacl_offset || 1382 check_add_overflow(dacl_offset, sizeof(struct smb_acl), &dacl_struct_end) || 1383 dacl_struct_end > (size_t)pntsd_size) 1384 goto err_out; 1385 1386 pdacl = (struct smb_acl *)((char *)pntsd + le32_to_cpu(pntsd->dacloffset)); 1387 acl_size = pntsd_size - dacl_offset; 1388 pdacl_size = le16_to_cpu(pdacl->size); 1389 1390 if (pdacl_size > acl_size || pdacl_size < sizeof(struct smb_acl)) 1391 goto err_out; 1392 1393 if (!pdacl->num_aces) { 1394 if (!(pdacl_size - sizeof(struct smb_acl)) && 1395 *pdaccess & ~(FILE_READ_CONTROL_LE | FILE_WRITE_DAC_LE)) { 1396 rc = -EACCES; 1397 goto err_out; 1398 } 1399 goto err_out; 1400 } 1401 1402 if (*pdaccess & FILE_MAXIMAL_ACCESS_LE) { 1403 granted = READ_CONTROL | WRITE_DAC | FILE_READ_ATTRIBUTES | 1404 DELETE; 1405 1406 ace = (struct smb_ace *)((char *)pdacl + sizeof(struct smb_acl)); 1407 aces_size = acl_size - sizeof(struct smb_acl); 1408 for (i = 0; i < le16_to_cpu(pdacl->num_aces); i++) { 1409 if (offsetof(struct smb_ace, sid) + 1410 aces_size < CIFS_SID_BASE_SIZE) 1411 break; 1412 ace_size = le16_to_cpu(ace->size); 1413 if (ace_size > aces_size || 1414 ace_size < offsetof(struct smb_ace, sid) + 1415 CIFS_SID_BASE_SIZE) 1416 break; 1417 aces_size -= ace_size; 1418 granted |= le32_to_cpu(ace->access_req); 1419 ace = (struct smb_ace *)((char *)ace + le16_to_cpu(ace->size)); 1420 } 1421 } 1422 1423 if (!uid) 1424 sid_type = SIDUNIX_USER; 1425 id_to_sid(uid, sid_type, &sid); 1426 1427 ace = (struct smb_ace *)((char *)pdacl + sizeof(struct smb_acl)); 1428 aces_size = acl_size - sizeof(struct smb_acl); 1429 for (i = 0; i < le16_to_cpu(pdacl->num_aces); i++) { 1430 if (offsetof(struct smb_ace, sid) + 1431 aces_size < CIFS_SID_BASE_SIZE) 1432 break; 1433 ace_size = le16_to_cpu(ace->size); 1434 if (ace_size > aces_size || 1435 ace_size < offsetof(struct smb_ace, sid) + 1436 CIFS_SID_BASE_SIZE) 1437 break; 1438 aces_size -= ace_size; 1439 1440 if (ace->sid.num_subauth > SID_MAX_SUB_AUTHORITIES) 1441 break; 1442 1443 if (!compare_sids(&sid, &ace->sid) || 1444 !compare_sids(&sid_unix_NFS_mode, &ace->sid)) { 1445 found = 1; 1446 break; 1447 } 1448 if (!compare_sids(&sid_everyone, &ace->sid)) 1449 others_ace = ace; 1450 1451 ace = (struct smb_ace *)((char *)ace + le16_to_cpu(ace->size)); 1452 } 1453 1454 if (*pdaccess & FILE_MAXIMAL_ACCESS_LE && found) { 1455 granted = READ_CONTROL | WRITE_DAC | FILE_READ_ATTRIBUTES | 1456 DELETE; 1457 1458 granted |= le32_to_cpu(ace->access_req); 1459 1460 if (!pdacl->num_aces) 1461 granted = GENERIC_ALL_FLAGS; 1462 } 1463 1464 if (IS_ENABLED(CONFIG_FS_POSIX_ACL)) { 1465 posix_acls = get_inode_acl(d_inode(path->dentry), ACL_TYPE_ACCESS); 1466 if (!IS_ERR_OR_NULL(posix_acls) && !found) { 1467 unsigned int id = -1; 1468 1469 pa_entry = posix_acls->a_entries; 1470 for (i = 0; i < posix_acls->a_count; i++, pa_entry++) { 1471 if (pa_entry->e_tag == ACL_USER) 1472 id = posix_acl_uid_translate(idmap, pa_entry); 1473 else if (pa_entry->e_tag == ACL_GROUP) 1474 id = posix_acl_gid_translate(idmap, pa_entry); 1475 else 1476 continue; 1477 1478 if (id == uid) { 1479 mode_to_access_flags(pa_entry->e_perm, 1480 0777, 1481 &access_bits); 1482 if (!access_bits) 1483 access_bits = 1484 SET_MINIMUM_RIGHTS; 1485 posix_acl_release(posix_acls); 1486 goto check_access_bits; 1487 } 1488 } 1489 } 1490 if (!IS_ERR_OR_NULL(posix_acls)) 1491 posix_acl_release(posix_acls); 1492 } 1493 1494 if (!found) { 1495 if (others_ace) { 1496 ace = others_ace; 1497 } else { 1498 ksmbd_debug(SMB, "Can't find corresponding sid\n"); 1499 rc = -EACCES; 1500 goto err_out; 1501 } 1502 } 1503 1504 switch (ace->type) { 1505 case ACCESS_ALLOWED_ACE_TYPE: 1506 access_bits = le32_to_cpu(ace->access_req); 1507 break; 1508 case ACCESS_DENIED_ACE_TYPE: 1509 case ACCESS_DENIED_CALLBACK_ACE_TYPE: 1510 access_bits = le32_to_cpu(~ace->access_req); 1511 break; 1512 } 1513 1514 check_access_bits: 1515 if (granted & 1516 ~(access_bits | FILE_READ_ATTRIBUTES | READ_CONTROL | WRITE_DAC | DELETE)) { 1517 ksmbd_debug(SMB, "Access denied with winACL, granted : %x, access_req : %x\n", 1518 granted, le32_to_cpu(ace->access_req)); 1519 rc = -EACCES; 1520 goto err_out; 1521 } 1522 1523 *pdaccess = cpu_to_le32(granted); 1524 err_out: 1525 kfree(pntsd); 1526 return rc; 1527 } 1528 1529 int set_info_sec(struct ksmbd_conn *conn, struct ksmbd_tree_connect *tcon, 1530 const struct path *path, struct smb_ntsd *pntsd, int ntsd_len, 1531 bool type_check, bool get_write) 1532 { 1533 int rc; 1534 struct smb_fattr fattr = {{0}}; 1535 struct inode *inode = d_inode(path->dentry); 1536 struct mnt_idmap *idmap = mnt_idmap(path->mnt); 1537 struct iattr newattrs; 1538 1539 fattr.cf_uid = INVALID_UID; 1540 fattr.cf_gid = INVALID_GID; 1541 fattr.cf_mode = inode->i_mode; 1542 1543 rc = parse_sec_desc(idmap, pntsd, ntsd_len, &fattr); 1544 if (rc) 1545 goto out; 1546 1547 newattrs.ia_valid = ATTR_CTIME; 1548 if (!uid_eq(fattr.cf_uid, INVALID_UID)) { 1549 newattrs.ia_valid |= ATTR_UID; 1550 newattrs.ia_uid = fattr.cf_uid; 1551 } 1552 if (!gid_eq(fattr.cf_gid, INVALID_GID)) { 1553 newattrs.ia_valid |= ATTR_GID; 1554 newattrs.ia_gid = fattr.cf_gid; 1555 } 1556 newattrs.ia_valid |= ATTR_MODE; 1557 newattrs.ia_mode = (inode->i_mode & ~0777) | (fattr.cf_mode & 0777); 1558 1559 ksmbd_vfs_remove_acl_xattrs(idmap, path); 1560 /* Update posix acls */ 1561 if (IS_ENABLED(CONFIG_FS_POSIX_ACL) && fattr.cf_dacls) { 1562 rc = set_posix_acl(idmap, path->dentry, 1563 ACL_TYPE_ACCESS, fattr.cf_acls); 1564 if (rc < 0) 1565 ksmbd_debug(SMB, 1566 "Set posix acl(ACL_TYPE_ACCESS) failed, rc : %d\n", 1567 rc); 1568 if (S_ISDIR(inode->i_mode) && fattr.cf_dacls) { 1569 rc = set_posix_acl(idmap, path->dentry, 1570 ACL_TYPE_DEFAULT, fattr.cf_dacls); 1571 if (rc) 1572 ksmbd_debug(SMB, 1573 "Set posix acl(ACL_TYPE_DEFAULT) failed, rc : %d\n", 1574 rc); 1575 } 1576 } 1577 1578 inode_lock(inode); 1579 rc = notify_change(idmap, path->dentry, &newattrs, NULL); 1580 inode_unlock(inode); 1581 if (rc) 1582 goto out; 1583 1584 /* Check it only calling from SD BUFFER context */ 1585 if (type_check && !(le16_to_cpu(pntsd->type) & DACL_PRESENT)) 1586 goto out; 1587 1588 if (test_share_config_flag(tcon->share_conf, KSMBD_SHARE_FLAG_ACL_XATTR)) { 1589 /* Update WinACL in xattr */ 1590 ksmbd_vfs_remove_sd_xattrs(idmap, path); 1591 ksmbd_vfs_set_sd_xattr(conn, idmap, path, pntsd, ntsd_len, 1592 get_write); 1593 } 1594 1595 out: 1596 posix_acl_release(fattr.cf_acls); 1597 posix_acl_release(fattr.cf_dacls); 1598 return rc; 1599 } 1600 1601 void ksmbd_init_domain(u32 *sub_auth) 1602 { 1603 int i; 1604 1605 memcpy(&server_conf.domain_sid, &domain, sizeof(struct smb_sid)); 1606 for (i = 0; i < 3; ++i) 1607 server_conf.domain_sid.sub_auth[i + 1] = cpu_to_le32(sub_auth[i]); 1608 } 1609