1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * Security plug functions 4 * 5 * Copyright (C) 2001 WireX Communications, Inc <chris@wirex.com> 6 * Copyright (C) 2001-2002 Greg Kroah-Hartman <greg@kroah.com> 7 * Copyright (C) 2001 Networks Associates Technology, Inc <ssmalley@nai.com> 8 * Copyright (C) 2016 Mellanox Technologies 9 * Copyright (C) 2023 Microsoft Corporation <paul@paul-moore.com> 10 */ 11 12 #define pr_fmt(fmt) "LSM: " fmt 13 14 #include <linux/bpf.h> 15 #include <linux/capability.h> 16 #include <linux/dcache.h> 17 #include <linux/export.h> 18 #include <linux/init.h> 19 #include <linux/kernel.h> 20 #include <linux/kernel_read_file.h> 21 #include <linux/lsm_hooks.h> 22 #include <linux/fsnotify.h> 23 #include <linux/mman.h> 24 #include <linux/mount.h> 25 #include <linux/personality.h> 26 #include <linux/backing-dev.h> 27 #include <linux/string.h> 28 #include <linux/xattr.h> 29 #include <linux/msg.h> 30 #include <linux/overflow.h> 31 #include <linux/perf_event.h> 32 #include <linux/fs.h> 33 #include <net/flow.h> 34 #include <net/sock.h> 35 36 #define SECURITY_HOOK_ACTIVE_KEY(HOOK, IDX) security_hook_active_##HOOK##_##IDX 37 38 /* 39 * Identifier for the LSM static calls. 40 * HOOK is an LSM hook as defined in linux/lsm_hookdefs.h 41 * IDX is the index of the static call. 0 <= NUM < MAX_LSM_COUNT 42 */ 43 #define LSM_STATIC_CALL(HOOK, IDX) lsm_static_call_##HOOK##_##IDX 44 45 /* 46 * Call the macro M for each LSM hook MAX_LSM_COUNT times. 47 */ 48 #define LSM_LOOP_UNROLL(M, ...) \ 49 do { \ 50 UNROLL(MAX_LSM_COUNT, M, __VA_ARGS__) \ 51 } while (0) 52 53 #define LSM_DEFINE_UNROLL(M, ...) UNROLL(MAX_LSM_COUNT, M, __VA_ARGS__) 54 55 /* 56 * These are descriptions of the reasons that can be passed to the 57 * security_locked_down() LSM hook. Placing this array here allows 58 * all security modules to use the same descriptions for auditing 59 * purposes. 60 */ 61 const char *const lockdown_reasons[LOCKDOWN_CONFIDENTIALITY_MAX + 1] = { 62 [LOCKDOWN_NONE] = "none", 63 [LOCKDOWN_MODULE_SIGNATURE] = "unsigned module loading", 64 [LOCKDOWN_DEV_MEM] = "/dev/mem,kmem,port", 65 [LOCKDOWN_EFI_TEST] = "/dev/efi_test access", 66 [LOCKDOWN_KEXEC] = "kexec of unsigned images", 67 [LOCKDOWN_HIBERNATION] = "hibernation", 68 [LOCKDOWN_PCI_ACCESS] = "direct PCI access", 69 [LOCKDOWN_IOPORT] = "raw io port access", 70 [LOCKDOWN_MSR] = "raw MSR access", 71 [LOCKDOWN_ACPI_TABLES] = "modifying ACPI tables", 72 [LOCKDOWN_DEVICE_TREE] = "modifying device tree contents", 73 [LOCKDOWN_PCMCIA_CIS] = "direct PCMCIA CIS storage", 74 [LOCKDOWN_TIOCSSERIAL] = "reconfiguration of serial port IO", 75 [LOCKDOWN_MODULE_PARAMETERS] = "unsafe module parameters", 76 [LOCKDOWN_MMIOTRACE] = "unsafe mmio", 77 [LOCKDOWN_DEBUGFS] = "debugfs access", 78 [LOCKDOWN_XMON_WR] = "xmon write access", 79 [LOCKDOWN_BPF_WRITE_USER] = "use of bpf to write user RAM", 80 [LOCKDOWN_DBG_WRITE_KERNEL] = "use of kgdb/kdb to write kernel RAM", 81 [LOCKDOWN_RTAS_ERROR_INJECTION] = "RTAS error injection", 82 [LOCKDOWN_INTEGRITY_MAX] = "integrity", 83 [LOCKDOWN_KCORE] = "/proc/kcore access", 84 [LOCKDOWN_KPROBES] = "use of kprobes", 85 [LOCKDOWN_BPF_READ_KERNEL] = "use of bpf to read kernel RAM", 86 [LOCKDOWN_DBG_READ_KERNEL] = "use of kgdb/kdb to read kernel RAM", 87 [LOCKDOWN_PERF] = "unsafe use of perf", 88 [LOCKDOWN_TRACEFS] = "use of tracefs", 89 [LOCKDOWN_XMON_RW] = "xmon read and write access", 90 [LOCKDOWN_XFRM_SECRET] = "xfrm SA secret", 91 [LOCKDOWN_CONFIDENTIALITY_MAX] = "confidentiality", 92 }; 93 94 static BLOCKING_NOTIFIER_HEAD(blocking_lsm_notifier_chain); 95 96 static struct kmem_cache *lsm_file_cache; 97 static struct kmem_cache *lsm_inode_cache; 98 99 char *lsm_names; 100 static struct lsm_blob_sizes blob_sizes __ro_after_init; 101 102 /* Boot-time LSM user choice */ 103 static __initdata const char *chosen_lsm_order; 104 static __initdata const char *chosen_major_lsm; 105 106 static __initconst const char *const builtin_lsm_order = CONFIG_LSM; 107 108 /* Ordered list of LSMs to initialize. */ 109 static __initdata struct lsm_info *ordered_lsms[MAX_LSM_COUNT + 1]; 110 static __initdata struct lsm_info *exclusive; 111 112 #ifdef CONFIG_HAVE_STATIC_CALL 113 #define LSM_HOOK_TRAMP(NAME, NUM) \ 114 &STATIC_CALL_TRAMP(LSM_STATIC_CALL(NAME, NUM)) 115 #else 116 #define LSM_HOOK_TRAMP(NAME, NUM) NULL 117 #endif 118 119 /* 120 * Define static calls and static keys for each LSM hook. 121 */ 122 #define DEFINE_LSM_STATIC_CALL(NUM, NAME, RET, ...) \ 123 DEFINE_STATIC_CALL_NULL(LSM_STATIC_CALL(NAME, NUM), \ 124 *((RET(*)(__VA_ARGS__))NULL)); \ 125 DEFINE_STATIC_KEY_FALSE(SECURITY_HOOK_ACTIVE_KEY(NAME, NUM)); 126 127 #define LSM_HOOK(RET, DEFAULT, NAME, ...) \ 128 LSM_DEFINE_UNROLL(DEFINE_LSM_STATIC_CALL, NAME, RET, __VA_ARGS__) 129 #include <linux/lsm_hook_defs.h> 130 #undef LSM_HOOK 131 #undef DEFINE_LSM_STATIC_CALL 132 133 /* 134 * Initialise a table of static calls for each LSM hook. 135 * DEFINE_STATIC_CALL_NULL invocation above generates a key (STATIC_CALL_KEY) 136 * and a trampoline (STATIC_CALL_TRAMP) which are used to call 137 * __static_call_update when updating the static call. 138 * 139 * The static calls table is used by early LSMs, some architectures can fault on 140 * unaligned accesses and the fault handling code may not be ready by then. 141 * Thus, the static calls table should be aligned to avoid any unhandled faults 142 * in early init. 143 */ 144 struct lsm_static_calls_table 145 static_calls_table __ro_after_init __aligned(sizeof(u64)) = { 146 #define INIT_LSM_STATIC_CALL(NUM, NAME) \ 147 (struct lsm_static_call) { \ 148 .key = &STATIC_CALL_KEY(LSM_STATIC_CALL(NAME, NUM)), \ 149 .trampoline = LSM_HOOK_TRAMP(NAME, NUM), \ 150 .active = &SECURITY_HOOK_ACTIVE_KEY(NAME, NUM), \ 151 }, 152 #define LSM_HOOK(RET, DEFAULT, NAME, ...) \ 153 .NAME = { \ 154 LSM_DEFINE_UNROLL(INIT_LSM_STATIC_CALL, NAME) \ 155 }, 156 #include <linux/lsm_hook_defs.h> 157 #undef LSM_HOOK 158 #undef INIT_LSM_STATIC_CALL 159 }; 160 161 static __initdata bool debug; 162 #define init_debug(...) \ 163 do { \ 164 if (debug) \ 165 pr_info(__VA_ARGS__); \ 166 } while (0) 167 168 static bool __init is_enabled(struct lsm_info *lsm) 169 { 170 if (!lsm->enabled) 171 return false; 172 173 return *lsm->enabled; 174 } 175 176 /* Mark an LSM's enabled flag. */ 177 static int lsm_enabled_true __initdata = 1; 178 static int lsm_enabled_false __initdata = 0; 179 static void __init set_enabled(struct lsm_info *lsm, bool enabled) 180 { 181 /* 182 * When an LSM hasn't configured an enable variable, we can use 183 * a hard-coded location for storing the default enabled state. 184 */ 185 if (!lsm->enabled) { 186 if (enabled) 187 lsm->enabled = &lsm_enabled_true; 188 else 189 lsm->enabled = &lsm_enabled_false; 190 } else if (lsm->enabled == &lsm_enabled_true) { 191 if (!enabled) 192 lsm->enabled = &lsm_enabled_false; 193 } else if (lsm->enabled == &lsm_enabled_false) { 194 if (enabled) 195 lsm->enabled = &lsm_enabled_true; 196 } else { 197 *lsm->enabled = enabled; 198 } 199 } 200 201 /* Is an LSM already listed in the ordered LSMs list? */ 202 static bool __init exists_ordered_lsm(struct lsm_info *lsm) 203 { 204 struct lsm_info **check; 205 206 for (check = ordered_lsms; *check; check++) 207 if (*check == lsm) 208 return true; 209 210 return false; 211 } 212 213 /* Append an LSM to the list of ordered LSMs to initialize. */ 214 static int last_lsm __initdata; 215 static void __init append_ordered_lsm(struct lsm_info *lsm, const char *from) 216 { 217 /* Ignore duplicate selections. */ 218 if (exists_ordered_lsm(lsm)) 219 return; 220 221 if (WARN(last_lsm == MAX_LSM_COUNT, "%s: out of LSM static calls!?\n", from)) 222 return; 223 224 /* Enable this LSM, if it is not already set. */ 225 if (!lsm->enabled) 226 lsm->enabled = &lsm_enabled_true; 227 ordered_lsms[last_lsm++] = lsm; 228 229 init_debug("%s ordered: %s (%s)\n", from, lsm->name, 230 is_enabled(lsm) ? "enabled" : "disabled"); 231 } 232 233 /* Is an LSM allowed to be initialized? */ 234 static bool __init lsm_allowed(struct lsm_info *lsm) 235 { 236 /* Skip if the LSM is disabled. */ 237 if (!is_enabled(lsm)) 238 return false; 239 240 /* Not allowed if another exclusive LSM already initialized. */ 241 if ((lsm->flags & LSM_FLAG_EXCLUSIVE) && exclusive) { 242 init_debug("exclusive disabled: %s\n", lsm->name); 243 return false; 244 } 245 246 return true; 247 } 248 249 static void __init lsm_set_blob_size(int *need, int *lbs) 250 { 251 int offset; 252 253 if (*need <= 0) 254 return; 255 256 offset = ALIGN(*lbs, sizeof(void *)); 257 *lbs = offset + *need; 258 *need = offset; 259 } 260 261 static void __init lsm_set_blob_sizes(struct lsm_blob_sizes *needed) 262 { 263 if (!needed) 264 return; 265 266 lsm_set_blob_size(&needed->lbs_cred, &blob_sizes.lbs_cred); 267 lsm_set_blob_size(&needed->lbs_file, &blob_sizes.lbs_file); 268 lsm_set_blob_size(&needed->lbs_ib, &blob_sizes.lbs_ib); 269 /* 270 * The inode blob gets an rcu_head in addition to 271 * what the modules might need. 272 */ 273 if (needed->lbs_inode && blob_sizes.lbs_inode == 0) 274 blob_sizes.lbs_inode = sizeof(struct rcu_head); 275 lsm_set_blob_size(&needed->lbs_inode, &blob_sizes.lbs_inode); 276 lsm_set_blob_size(&needed->lbs_ipc, &blob_sizes.lbs_ipc); 277 lsm_set_blob_size(&needed->lbs_key, &blob_sizes.lbs_key); 278 lsm_set_blob_size(&needed->lbs_msg_msg, &blob_sizes.lbs_msg_msg); 279 lsm_set_blob_size(&needed->lbs_perf_event, &blob_sizes.lbs_perf_event); 280 lsm_set_blob_size(&needed->lbs_sock, &blob_sizes.lbs_sock); 281 lsm_set_blob_size(&needed->lbs_superblock, &blob_sizes.lbs_superblock); 282 lsm_set_blob_size(&needed->lbs_task, &blob_sizes.lbs_task); 283 lsm_set_blob_size(&needed->lbs_tun_dev, &blob_sizes.lbs_tun_dev); 284 lsm_set_blob_size(&needed->lbs_xattr_count, 285 &blob_sizes.lbs_xattr_count); 286 lsm_set_blob_size(&needed->lbs_bdev, &blob_sizes.lbs_bdev); 287 } 288 289 /* Prepare LSM for initialization. */ 290 static void __init prepare_lsm(struct lsm_info *lsm) 291 { 292 int enabled = lsm_allowed(lsm); 293 294 /* Record enablement (to handle any following exclusive LSMs). */ 295 set_enabled(lsm, enabled); 296 297 /* If enabled, do pre-initialization work. */ 298 if (enabled) { 299 if ((lsm->flags & LSM_FLAG_EXCLUSIVE) && !exclusive) { 300 exclusive = lsm; 301 init_debug("exclusive chosen: %s\n", lsm->name); 302 } 303 304 lsm_set_blob_sizes(lsm->blobs); 305 } 306 } 307 308 /* Initialize a given LSM, if it is enabled. */ 309 static void __init initialize_lsm(struct lsm_info *lsm) 310 { 311 if (is_enabled(lsm)) { 312 int ret; 313 314 init_debug("initializing %s\n", lsm->name); 315 ret = lsm->init(); 316 WARN(ret, "%s failed to initialize: %d\n", lsm->name, ret); 317 } 318 } 319 320 /* 321 * Current index to use while initializing the lsm id list. 322 */ 323 u32 lsm_active_cnt __ro_after_init; 324 const struct lsm_id *lsm_idlist[MAX_LSM_COUNT]; 325 326 /* Populate ordered LSMs list from comma-separated LSM name list. */ 327 static void __init ordered_lsm_parse(const char *order, const char *origin) 328 { 329 struct lsm_info *lsm; 330 char *sep, *name, *next; 331 332 /* LSM_ORDER_FIRST is always first. */ 333 for (lsm = __start_lsm_info; lsm < __end_lsm_info; lsm++) { 334 if (lsm->order == LSM_ORDER_FIRST) 335 append_ordered_lsm(lsm, " first"); 336 } 337 338 /* Process "security=", if given. */ 339 if (chosen_major_lsm) { 340 struct lsm_info *major; 341 342 /* 343 * To match the original "security=" behavior, this 344 * explicitly does NOT fallback to another Legacy Major 345 * if the selected one was separately disabled: disable 346 * all non-matching Legacy Major LSMs. 347 */ 348 for (major = __start_lsm_info; major < __end_lsm_info; 349 major++) { 350 if ((major->flags & LSM_FLAG_LEGACY_MAJOR) && 351 strcmp(major->name, chosen_major_lsm) != 0) { 352 set_enabled(major, false); 353 init_debug("security=%s disabled: %s (only one legacy major LSM)\n", 354 chosen_major_lsm, major->name); 355 } 356 } 357 } 358 359 sep = kstrdup(order, GFP_KERNEL); 360 next = sep; 361 /* Walk the list, looking for matching LSMs. */ 362 while ((name = strsep(&next, ",")) != NULL) { 363 bool found = false; 364 365 for (lsm = __start_lsm_info; lsm < __end_lsm_info; lsm++) { 366 if (strcmp(lsm->name, name) == 0) { 367 if (lsm->order == LSM_ORDER_MUTABLE) 368 append_ordered_lsm(lsm, origin); 369 found = true; 370 } 371 } 372 373 if (!found) 374 init_debug("%s ignored: %s (not built into kernel)\n", 375 origin, name); 376 } 377 378 /* Process "security=", if given. */ 379 if (chosen_major_lsm) { 380 for (lsm = __start_lsm_info; lsm < __end_lsm_info; lsm++) { 381 if (exists_ordered_lsm(lsm)) 382 continue; 383 if (strcmp(lsm->name, chosen_major_lsm) == 0) 384 append_ordered_lsm(lsm, "security="); 385 } 386 } 387 388 /* LSM_ORDER_LAST is always last. */ 389 for (lsm = __start_lsm_info; lsm < __end_lsm_info; lsm++) { 390 if (lsm->order == LSM_ORDER_LAST) 391 append_ordered_lsm(lsm, " last"); 392 } 393 394 /* Disable all LSMs not in the ordered list. */ 395 for (lsm = __start_lsm_info; lsm < __end_lsm_info; lsm++) { 396 if (exists_ordered_lsm(lsm)) 397 continue; 398 set_enabled(lsm, false); 399 init_debug("%s skipped: %s (not in requested order)\n", 400 origin, lsm->name); 401 } 402 403 kfree(sep); 404 } 405 406 static void __init lsm_static_call_init(struct security_hook_list *hl) 407 { 408 struct lsm_static_call *scall = hl->scalls; 409 int i; 410 411 for (i = 0; i < MAX_LSM_COUNT; i++) { 412 /* Update the first static call that is not used yet */ 413 if (!scall->hl) { 414 __static_call_update(scall->key, scall->trampoline, 415 hl->hook.lsm_func_addr); 416 scall->hl = hl; 417 static_branch_enable(scall->active); 418 return; 419 } 420 scall++; 421 } 422 panic("%s - Ran out of static slots.\n", __func__); 423 } 424 425 static void __init lsm_early_cred(struct cred *cred); 426 static void __init lsm_early_task(struct task_struct *task); 427 428 static int lsm_append(const char *new, char **result); 429 430 static void __init report_lsm_order(void) 431 { 432 struct lsm_info **lsm, *early; 433 int first = 0; 434 435 pr_info("initializing lsm="); 436 437 /* Report each enabled LSM name, comma separated. */ 438 for (early = __start_early_lsm_info; 439 early < __end_early_lsm_info; early++) 440 if (is_enabled(early)) 441 pr_cont("%s%s", first++ == 0 ? "" : ",", early->name); 442 for (lsm = ordered_lsms; *lsm; lsm++) 443 if (is_enabled(*lsm)) 444 pr_cont("%s%s", first++ == 0 ? "" : ",", (*lsm)->name); 445 446 pr_cont("\n"); 447 } 448 449 static void __init ordered_lsm_init(void) 450 { 451 struct lsm_info **lsm; 452 453 if (chosen_lsm_order) { 454 if (chosen_major_lsm) { 455 pr_warn("security=%s is ignored because it is superseded by lsm=%s\n", 456 chosen_major_lsm, chosen_lsm_order); 457 chosen_major_lsm = NULL; 458 } 459 ordered_lsm_parse(chosen_lsm_order, "cmdline"); 460 } else 461 ordered_lsm_parse(builtin_lsm_order, "builtin"); 462 463 for (lsm = ordered_lsms; *lsm; lsm++) 464 prepare_lsm(*lsm); 465 466 report_lsm_order(); 467 468 init_debug("cred blob size = %d\n", blob_sizes.lbs_cred); 469 init_debug("file blob size = %d\n", blob_sizes.lbs_file); 470 init_debug("ib blob size = %d\n", blob_sizes.lbs_ib); 471 init_debug("inode blob size = %d\n", blob_sizes.lbs_inode); 472 init_debug("ipc blob size = %d\n", blob_sizes.lbs_ipc); 473 #ifdef CONFIG_KEYS 474 init_debug("key blob size = %d\n", blob_sizes.lbs_key); 475 #endif /* CONFIG_KEYS */ 476 init_debug("msg_msg blob size = %d\n", blob_sizes.lbs_msg_msg); 477 init_debug("sock blob size = %d\n", blob_sizes.lbs_sock); 478 init_debug("superblock blob size = %d\n", blob_sizes.lbs_superblock); 479 init_debug("perf event blob size = %d\n", blob_sizes.lbs_perf_event); 480 init_debug("task blob size = %d\n", blob_sizes.lbs_task); 481 init_debug("tun device blob size = %d\n", blob_sizes.lbs_tun_dev); 482 init_debug("xattr slots = %d\n", blob_sizes.lbs_xattr_count); 483 init_debug("bdev blob size = %d\n", blob_sizes.lbs_bdev); 484 485 /* 486 * Create any kmem_caches needed for blobs 487 */ 488 if (blob_sizes.lbs_file) 489 lsm_file_cache = kmem_cache_create("lsm_file_cache", 490 blob_sizes.lbs_file, 0, 491 SLAB_PANIC, NULL); 492 if (blob_sizes.lbs_inode) 493 lsm_inode_cache = kmem_cache_create("lsm_inode_cache", 494 blob_sizes.lbs_inode, 0, 495 SLAB_PANIC, NULL); 496 497 lsm_early_cred((struct cred *) current->cred); 498 lsm_early_task(current); 499 for (lsm = ordered_lsms; *lsm; lsm++) 500 initialize_lsm(*lsm); 501 } 502 503 int __init early_security_init(void) 504 { 505 struct lsm_info *lsm; 506 507 for (lsm = __start_early_lsm_info; lsm < __end_early_lsm_info; lsm++) { 508 if (!lsm->enabled) 509 lsm->enabled = &lsm_enabled_true; 510 prepare_lsm(lsm); 511 initialize_lsm(lsm); 512 } 513 514 return 0; 515 } 516 517 /** 518 * security_init - initializes the security framework 519 * 520 * This should be called early in the kernel initialization sequence. 521 */ 522 int __init security_init(void) 523 { 524 struct lsm_info *lsm; 525 526 init_debug("legacy security=%s\n", chosen_major_lsm ? : " *unspecified*"); 527 init_debug(" CONFIG_LSM=%s\n", builtin_lsm_order); 528 init_debug("boot arg lsm=%s\n", chosen_lsm_order ? : " *unspecified*"); 529 530 /* 531 * Append the names of the early LSM modules now that kmalloc() is 532 * available 533 */ 534 for (lsm = __start_early_lsm_info; lsm < __end_early_lsm_info; lsm++) { 535 init_debug(" early started: %s (%s)\n", lsm->name, 536 is_enabled(lsm) ? "enabled" : "disabled"); 537 if (lsm->enabled) 538 lsm_append(lsm->name, &lsm_names); 539 } 540 541 /* Load LSMs in specified order. */ 542 ordered_lsm_init(); 543 544 return 0; 545 } 546 547 /* Save user chosen LSM */ 548 static int __init choose_major_lsm(char *str) 549 { 550 chosen_major_lsm = str; 551 return 1; 552 } 553 __setup("security=", choose_major_lsm); 554 555 /* Explicitly choose LSM initialization order. */ 556 static int __init choose_lsm_order(char *str) 557 { 558 chosen_lsm_order = str; 559 return 1; 560 } 561 __setup("lsm=", choose_lsm_order); 562 563 /* Enable LSM order debugging. */ 564 static int __init enable_debug(char *str) 565 { 566 debug = true; 567 return 1; 568 } 569 __setup("lsm.debug", enable_debug); 570 571 static bool match_last_lsm(const char *list, const char *lsm) 572 { 573 const char *last; 574 575 if (WARN_ON(!list || !lsm)) 576 return false; 577 last = strrchr(list, ','); 578 if (last) 579 /* Pass the comma, strcmp() will check for '\0' */ 580 last++; 581 else 582 last = list; 583 return !strcmp(last, lsm); 584 } 585 586 static int lsm_append(const char *new, char **result) 587 { 588 char *cp; 589 590 if (*result == NULL) { 591 *result = kstrdup(new, GFP_KERNEL); 592 if (*result == NULL) 593 return -ENOMEM; 594 } else { 595 /* Check if it is the last registered name */ 596 if (match_last_lsm(*result, new)) 597 return 0; 598 cp = kasprintf(GFP_KERNEL, "%s,%s", *result, new); 599 if (cp == NULL) 600 return -ENOMEM; 601 kfree(*result); 602 *result = cp; 603 } 604 return 0; 605 } 606 607 /** 608 * security_add_hooks - Add a modules hooks to the hook lists. 609 * @hooks: the hooks to add 610 * @count: the number of hooks to add 611 * @lsmid: the identification information for the security module 612 * 613 * Each LSM has to register its hooks with the infrastructure. 614 */ 615 void __init security_add_hooks(struct security_hook_list *hooks, int count, 616 const struct lsm_id *lsmid) 617 { 618 int i; 619 620 /* 621 * A security module may call security_add_hooks() more 622 * than once during initialization, and LSM initialization 623 * is serialized. Landlock is one such case. 624 * Look at the previous entry, if there is one, for duplication. 625 */ 626 if (lsm_active_cnt == 0 || lsm_idlist[lsm_active_cnt - 1] != lsmid) { 627 if (lsm_active_cnt >= MAX_LSM_COUNT) 628 panic("%s Too many LSMs registered.\n", __func__); 629 lsm_idlist[lsm_active_cnt++] = lsmid; 630 } 631 632 for (i = 0; i < count; i++) { 633 hooks[i].lsmid = lsmid; 634 lsm_static_call_init(&hooks[i]); 635 } 636 637 /* 638 * Don't try to append during early_security_init(), we'll come back 639 * and fix this up afterwards. 640 */ 641 if (slab_is_available()) { 642 if (lsm_append(lsmid->name, &lsm_names) < 0) 643 panic("%s - Cannot get early memory.\n", __func__); 644 } 645 } 646 647 int call_blocking_lsm_notifier(enum lsm_event event, void *data) 648 { 649 return blocking_notifier_call_chain(&blocking_lsm_notifier_chain, 650 event, data); 651 } 652 EXPORT_SYMBOL(call_blocking_lsm_notifier); 653 654 int register_blocking_lsm_notifier(struct notifier_block *nb) 655 { 656 return blocking_notifier_chain_register(&blocking_lsm_notifier_chain, 657 nb); 658 } 659 EXPORT_SYMBOL(register_blocking_lsm_notifier); 660 661 int unregister_blocking_lsm_notifier(struct notifier_block *nb) 662 { 663 return blocking_notifier_chain_unregister(&blocking_lsm_notifier_chain, 664 nb); 665 } 666 EXPORT_SYMBOL(unregister_blocking_lsm_notifier); 667 668 /** 669 * lsm_blob_alloc - allocate a composite blob 670 * @dest: the destination for the blob 671 * @size: the size of the blob 672 * @gfp: allocation type 673 * 674 * Allocate a blob for all the modules 675 * 676 * Returns 0, or -ENOMEM if memory can't be allocated. 677 */ 678 static int lsm_blob_alloc(void **dest, size_t size, gfp_t gfp) 679 { 680 if (size == 0) { 681 *dest = NULL; 682 return 0; 683 } 684 685 *dest = kzalloc(size, gfp); 686 if (*dest == NULL) 687 return -ENOMEM; 688 return 0; 689 } 690 691 /** 692 * lsm_cred_alloc - allocate a composite cred blob 693 * @cred: the cred that needs a blob 694 * @gfp: allocation type 695 * 696 * Allocate the cred blob for all the modules 697 * 698 * Returns 0, or -ENOMEM if memory can't be allocated. 699 */ 700 static int lsm_cred_alloc(struct cred *cred, gfp_t gfp) 701 { 702 return lsm_blob_alloc(&cred->security, blob_sizes.lbs_cred, gfp); 703 } 704 705 /** 706 * lsm_early_cred - during initialization allocate a composite cred blob 707 * @cred: the cred that needs a blob 708 * 709 * Allocate the cred blob for all the modules 710 */ 711 static void __init lsm_early_cred(struct cred *cred) 712 { 713 int rc = lsm_cred_alloc(cred, GFP_KERNEL); 714 715 if (rc) 716 panic("%s: Early cred alloc failed.\n", __func__); 717 } 718 719 /** 720 * lsm_file_alloc - allocate a composite file blob 721 * @file: the file that needs a blob 722 * 723 * Allocate the file blob for all the modules 724 * 725 * Returns 0, or -ENOMEM if memory can't be allocated. 726 */ 727 static int lsm_file_alloc(struct file *file) 728 { 729 if (!lsm_file_cache) { 730 file->f_security = NULL; 731 return 0; 732 } 733 734 file->f_security = kmem_cache_zalloc(lsm_file_cache, GFP_KERNEL); 735 if (file->f_security == NULL) 736 return -ENOMEM; 737 return 0; 738 } 739 740 /** 741 * lsm_inode_alloc - allocate a composite inode blob 742 * @inode: the inode that needs a blob 743 * @gfp: allocation flags 744 * 745 * Allocate the inode blob for all the modules 746 * 747 * Returns 0, or -ENOMEM if memory can't be allocated. 748 */ 749 static int lsm_inode_alloc(struct inode *inode, gfp_t gfp) 750 { 751 if (!lsm_inode_cache) { 752 inode->i_security = NULL; 753 return 0; 754 } 755 756 inode->i_security = kmem_cache_zalloc(lsm_inode_cache, gfp); 757 if (inode->i_security == NULL) 758 return -ENOMEM; 759 return 0; 760 } 761 762 /** 763 * lsm_task_alloc - allocate a composite task blob 764 * @task: the task that needs a blob 765 * 766 * Allocate the task blob for all the modules 767 * 768 * Returns 0, or -ENOMEM if memory can't be allocated. 769 */ 770 static int lsm_task_alloc(struct task_struct *task) 771 { 772 return lsm_blob_alloc(&task->security, blob_sizes.lbs_task, GFP_KERNEL); 773 } 774 775 /** 776 * lsm_ipc_alloc - allocate a composite ipc blob 777 * @kip: the ipc that needs a blob 778 * 779 * Allocate the ipc blob for all the modules 780 * 781 * Returns 0, or -ENOMEM if memory can't be allocated. 782 */ 783 static int lsm_ipc_alloc(struct kern_ipc_perm *kip) 784 { 785 return lsm_blob_alloc(&kip->security, blob_sizes.lbs_ipc, GFP_KERNEL); 786 } 787 788 #ifdef CONFIG_KEYS 789 /** 790 * lsm_key_alloc - allocate a composite key blob 791 * @key: the key that needs a blob 792 * 793 * Allocate the key blob for all the modules 794 * 795 * Returns 0, or -ENOMEM if memory can't be allocated. 796 */ 797 static int lsm_key_alloc(struct key *key) 798 { 799 return lsm_blob_alloc(&key->security, blob_sizes.lbs_key, GFP_KERNEL); 800 } 801 #endif /* CONFIG_KEYS */ 802 803 /** 804 * lsm_msg_msg_alloc - allocate a composite msg_msg blob 805 * @mp: the msg_msg that needs a blob 806 * 807 * Allocate the ipc blob for all the modules 808 * 809 * Returns 0, or -ENOMEM if memory can't be allocated. 810 */ 811 static int lsm_msg_msg_alloc(struct msg_msg *mp) 812 { 813 return lsm_blob_alloc(&mp->security, blob_sizes.lbs_msg_msg, 814 GFP_KERNEL); 815 } 816 817 /** 818 * lsm_bdev_alloc - allocate a composite block_device blob 819 * @bdev: the block_device that needs a blob 820 * 821 * Allocate the block_device blob for all the modules 822 * 823 * Returns 0, or -ENOMEM if memory can't be allocated. 824 */ 825 static int lsm_bdev_alloc(struct block_device *bdev) 826 { 827 if (blob_sizes.lbs_bdev == 0) { 828 bdev->bd_security = NULL; 829 return 0; 830 } 831 832 bdev->bd_security = kzalloc(blob_sizes.lbs_bdev, GFP_KERNEL); 833 if (!bdev->bd_security) 834 return -ENOMEM; 835 836 return 0; 837 } 838 839 /** 840 * lsm_early_task - during initialization allocate a composite task blob 841 * @task: the task that needs a blob 842 * 843 * Allocate the task blob for all the modules 844 */ 845 static void __init lsm_early_task(struct task_struct *task) 846 { 847 int rc = lsm_task_alloc(task); 848 849 if (rc) 850 panic("%s: Early task alloc failed.\n", __func__); 851 } 852 853 /** 854 * lsm_superblock_alloc - allocate a composite superblock blob 855 * @sb: the superblock that needs a blob 856 * 857 * Allocate the superblock blob for all the modules 858 * 859 * Returns 0, or -ENOMEM if memory can't be allocated. 860 */ 861 static int lsm_superblock_alloc(struct super_block *sb) 862 { 863 return lsm_blob_alloc(&sb->s_security, blob_sizes.lbs_superblock, 864 GFP_KERNEL); 865 } 866 867 /** 868 * lsm_fill_user_ctx - Fill a user space lsm_ctx structure 869 * @uctx: a userspace LSM context to be filled 870 * @uctx_len: available uctx size (input), used uctx size (output) 871 * @val: the new LSM context value 872 * @val_len: the size of the new LSM context value 873 * @id: LSM id 874 * @flags: LSM defined flags 875 * 876 * Fill all of the fields in a userspace lsm_ctx structure. If @uctx is NULL 877 * simply calculate the required size to output via @utc_len and return 878 * success. 879 * 880 * Returns 0 on success, -E2BIG if userspace buffer is not large enough, 881 * -EFAULT on a copyout error, -ENOMEM if memory can't be allocated. 882 */ 883 int lsm_fill_user_ctx(struct lsm_ctx __user *uctx, u32 *uctx_len, 884 void *val, size_t val_len, 885 u64 id, u64 flags) 886 { 887 struct lsm_ctx *nctx = NULL; 888 size_t nctx_len; 889 int rc = 0; 890 891 nctx_len = ALIGN(struct_size(nctx, ctx, val_len), sizeof(void *)); 892 if (nctx_len > *uctx_len) { 893 rc = -E2BIG; 894 goto out; 895 } 896 897 /* no buffer - return success/0 and set @uctx_len to the req size */ 898 if (!uctx) 899 goto out; 900 901 nctx = kzalloc(nctx_len, GFP_KERNEL); 902 if (nctx == NULL) { 903 rc = -ENOMEM; 904 goto out; 905 } 906 nctx->id = id; 907 nctx->flags = flags; 908 nctx->len = nctx_len; 909 nctx->ctx_len = val_len; 910 memcpy(nctx->ctx, val, val_len); 911 912 if (copy_to_user(uctx, nctx, nctx_len)) 913 rc = -EFAULT; 914 915 out: 916 kfree(nctx); 917 *uctx_len = nctx_len; 918 return rc; 919 } 920 921 /* 922 * The default value of the LSM hook is defined in linux/lsm_hook_defs.h and 923 * can be accessed with: 924 * 925 * LSM_RET_DEFAULT(<hook_name>) 926 * 927 * The macros below define static constants for the default value of each 928 * LSM hook. 929 */ 930 #define LSM_RET_DEFAULT(NAME) (NAME##_default) 931 #define DECLARE_LSM_RET_DEFAULT_void(DEFAULT, NAME) 932 #define DECLARE_LSM_RET_DEFAULT_int(DEFAULT, NAME) \ 933 static const int __maybe_unused LSM_RET_DEFAULT(NAME) = (DEFAULT); 934 #define LSM_HOOK(RET, DEFAULT, NAME, ...) \ 935 DECLARE_LSM_RET_DEFAULT_##RET(DEFAULT, NAME) 936 937 #include <linux/lsm_hook_defs.h> 938 #undef LSM_HOOK 939 940 /* 941 * Hook list operation macros. 942 * 943 * call_void_hook: 944 * This is a hook that does not return a value. 945 * 946 * call_int_hook: 947 * This is a hook that returns a value. 948 */ 949 #define __CALL_STATIC_VOID(NUM, HOOK, ...) \ 950 do { \ 951 if (static_branch_unlikely(&SECURITY_HOOK_ACTIVE_KEY(HOOK, NUM))) { \ 952 static_call(LSM_STATIC_CALL(HOOK, NUM))(__VA_ARGS__); \ 953 } \ 954 } while (0); 955 956 #define call_void_hook(HOOK, ...) \ 957 do { \ 958 LSM_LOOP_UNROLL(__CALL_STATIC_VOID, HOOK, __VA_ARGS__); \ 959 } while (0) 960 961 962 #define __CALL_STATIC_INT(NUM, R, HOOK, LABEL, ...) \ 963 do { \ 964 if (static_branch_unlikely(&SECURITY_HOOK_ACTIVE_KEY(HOOK, NUM))) { \ 965 R = static_call(LSM_STATIC_CALL(HOOK, NUM))(__VA_ARGS__); \ 966 if (R != LSM_RET_DEFAULT(HOOK)) \ 967 goto LABEL; \ 968 } \ 969 } while (0); 970 971 #define call_int_hook(HOOK, ...) \ 972 ({ \ 973 __label__ OUT; \ 974 int RC = LSM_RET_DEFAULT(HOOK); \ 975 \ 976 LSM_LOOP_UNROLL(__CALL_STATIC_INT, RC, HOOK, OUT, __VA_ARGS__); \ 977 OUT: \ 978 RC; \ 979 }) 980 981 #define lsm_for_each_hook(scall, NAME) \ 982 for (scall = static_calls_table.NAME; \ 983 scall - static_calls_table.NAME < MAX_LSM_COUNT; scall++) \ 984 if (static_key_enabled(&scall->active->key)) 985 986 /* Security operations */ 987 988 /** 989 * security_binder_set_context_mgr() - Check if becoming binder ctx mgr is ok 990 * @mgr: task credentials of current binder process 991 * 992 * Check whether @mgr is allowed to be the binder context manager. 993 * 994 * Return: Return 0 if permission is granted. 995 */ 996 int security_binder_set_context_mgr(const struct cred *mgr) 997 { 998 return call_int_hook(binder_set_context_mgr, mgr); 999 } 1000 1001 /** 1002 * security_binder_transaction() - Check if a binder transaction is allowed 1003 * @from: sending process 1004 * @to: receiving process 1005 * 1006 * Check whether @from is allowed to invoke a binder transaction call to @to. 1007 * 1008 * Return: Returns 0 if permission is granted. 1009 */ 1010 int security_binder_transaction(const struct cred *from, 1011 const struct cred *to) 1012 { 1013 return call_int_hook(binder_transaction, from, to); 1014 } 1015 1016 /** 1017 * security_binder_transfer_binder() - Check if a binder transfer is allowed 1018 * @from: sending process 1019 * @to: receiving process 1020 * 1021 * Check whether @from is allowed to transfer a binder reference to @to. 1022 * 1023 * Return: Returns 0 if permission is granted. 1024 */ 1025 int security_binder_transfer_binder(const struct cred *from, 1026 const struct cred *to) 1027 { 1028 return call_int_hook(binder_transfer_binder, from, to); 1029 } 1030 1031 /** 1032 * security_binder_transfer_file() - Check if a binder file xfer is allowed 1033 * @from: sending process 1034 * @to: receiving process 1035 * @file: file being transferred 1036 * 1037 * Check whether @from is allowed to transfer @file to @to. 1038 * 1039 * Return: Returns 0 if permission is granted. 1040 */ 1041 int security_binder_transfer_file(const struct cred *from, 1042 const struct cred *to, const struct file *file) 1043 { 1044 return call_int_hook(binder_transfer_file, from, to, file); 1045 } 1046 1047 /** 1048 * security_ptrace_access_check() - Check if tracing is allowed 1049 * @child: target process 1050 * @mode: PTRACE_MODE flags 1051 * 1052 * Check permission before allowing the current process to trace the @child 1053 * process. Security modules may also want to perform a process tracing check 1054 * during an execve in the set_security or apply_creds hooks of tracing check 1055 * during an execve in the bprm_set_creds hook of binprm_security_ops if the 1056 * process is being traced and its security attributes would be changed by the 1057 * execve. 1058 * 1059 * Return: Returns 0 if permission is granted. 1060 */ 1061 int security_ptrace_access_check(struct task_struct *child, unsigned int mode) 1062 { 1063 return call_int_hook(ptrace_access_check, child, mode); 1064 } 1065 1066 /** 1067 * security_ptrace_traceme() - Check if tracing is allowed 1068 * @parent: tracing process 1069 * 1070 * Check that the @parent process has sufficient permission to trace the 1071 * current process before allowing the current process to present itself to the 1072 * @parent process for tracing. 1073 * 1074 * Return: Returns 0 if permission is granted. 1075 */ 1076 int security_ptrace_traceme(struct task_struct *parent) 1077 { 1078 return call_int_hook(ptrace_traceme, parent); 1079 } 1080 1081 /** 1082 * security_capget() - Get the capability sets for a process 1083 * @target: target process 1084 * @effective: effective capability set 1085 * @inheritable: inheritable capability set 1086 * @permitted: permitted capability set 1087 * 1088 * Get the @effective, @inheritable, and @permitted capability sets for the 1089 * @target process. The hook may also perform permission checking to determine 1090 * if the current process is allowed to see the capability sets of the @target 1091 * process. 1092 * 1093 * Return: Returns 0 if the capability sets were successfully obtained. 1094 */ 1095 int security_capget(const struct task_struct *target, 1096 kernel_cap_t *effective, 1097 kernel_cap_t *inheritable, 1098 kernel_cap_t *permitted) 1099 { 1100 return call_int_hook(capget, target, effective, inheritable, permitted); 1101 } 1102 1103 /** 1104 * security_capset() - Set the capability sets for a process 1105 * @new: new credentials for the target process 1106 * @old: current credentials of the target process 1107 * @effective: effective capability set 1108 * @inheritable: inheritable capability set 1109 * @permitted: permitted capability set 1110 * 1111 * Set the @effective, @inheritable, and @permitted capability sets for the 1112 * current process. 1113 * 1114 * Return: Returns 0 and update @new if permission is granted. 1115 */ 1116 int security_capset(struct cred *new, const struct cred *old, 1117 const kernel_cap_t *effective, 1118 const kernel_cap_t *inheritable, 1119 const kernel_cap_t *permitted) 1120 { 1121 return call_int_hook(capset, new, old, effective, inheritable, 1122 permitted); 1123 } 1124 1125 /** 1126 * security_capable() - Check if a process has the necessary capability 1127 * @cred: credentials to examine 1128 * @ns: user namespace 1129 * @cap: capability requested 1130 * @opts: capability check options 1131 * 1132 * Check whether the @tsk process has the @cap capability in the indicated 1133 * credentials. @cap contains the capability <include/linux/capability.h>. 1134 * @opts contains options for the capable check <include/linux/security.h>. 1135 * 1136 * Return: Returns 0 if the capability is granted. 1137 */ 1138 int security_capable(const struct cred *cred, 1139 struct user_namespace *ns, 1140 int cap, 1141 unsigned int opts) 1142 { 1143 return call_int_hook(capable, cred, ns, cap, opts); 1144 } 1145 1146 /** 1147 * security_quotactl() - Check if a quotactl() syscall is allowed for this fs 1148 * @cmds: commands 1149 * @type: type 1150 * @id: id 1151 * @sb: filesystem 1152 * 1153 * Check whether the quotactl syscall is allowed for this @sb. 1154 * 1155 * Return: Returns 0 if permission is granted. 1156 */ 1157 int security_quotactl(int cmds, int type, int id, const struct super_block *sb) 1158 { 1159 return call_int_hook(quotactl, cmds, type, id, sb); 1160 } 1161 1162 /** 1163 * security_quota_on() - Check if QUOTAON is allowed for a dentry 1164 * @dentry: dentry 1165 * 1166 * Check whether QUOTAON is allowed for @dentry. 1167 * 1168 * Return: Returns 0 if permission is granted. 1169 */ 1170 int security_quota_on(struct dentry *dentry) 1171 { 1172 return call_int_hook(quota_on, dentry); 1173 } 1174 1175 /** 1176 * security_syslog() - Check if accessing the kernel message ring is allowed 1177 * @type: SYSLOG_ACTION_* type 1178 * 1179 * Check permission before accessing the kernel message ring or changing 1180 * logging to the console. See the syslog(2) manual page for an explanation of 1181 * the @type values. 1182 * 1183 * Return: Return 0 if permission is granted. 1184 */ 1185 int security_syslog(int type) 1186 { 1187 return call_int_hook(syslog, type); 1188 } 1189 1190 /** 1191 * security_settime64() - Check if changing the system time is allowed 1192 * @ts: new time 1193 * @tz: timezone 1194 * 1195 * Check permission to change the system time, struct timespec64 is defined in 1196 * <include/linux/time64.h> and timezone is defined in <include/linux/time.h>. 1197 * 1198 * Return: Returns 0 if permission is granted. 1199 */ 1200 int security_settime64(const struct timespec64 *ts, const struct timezone *tz) 1201 { 1202 return call_int_hook(settime, ts, tz); 1203 } 1204 1205 /** 1206 * security_vm_enough_memory_mm() - Check if allocating a new mem map is allowed 1207 * @mm: mm struct 1208 * @pages: number of pages 1209 * 1210 * Check permissions for allocating a new virtual mapping. If all LSMs return 1211 * a positive value, __vm_enough_memory() will be called with cap_sys_admin 1212 * set. If at least one LSM returns 0 or negative, __vm_enough_memory() will be 1213 * called with cap_sys_admin cleared. 1214 * 1215 * Return: Returns 0 if permission is granted by the LSM infrastructure to the 1216 * caller. 1217 */ 1218 int security_vm_enough_memory_mm(struct mm_struct *mm, long pages) 1219 { 1220 struct lsm_static_call *scall; 1221 int cap_sys_admin = 1; 1222 int rc; 1223 1224 /* 1225 * The module will respond with 0 if it thinks the __vm_enough_memory() 1226 * call should be made with the cap_sys_admin set. If all of the modules 1227 * agree that it should be set it will. If any module thinks it should 1228 * not be set it won't. 1229 */ 1230 lsm_for_each_hook(scall, vm_enough_memory) { 1231 rc = scall->hl->hook.vm_enough_memory(mm, pages); 1232 if (rc < 0) { 1233 cap_sys_admin = 0; 1234 break; 1235 } 1236 } 1237 return __vm_enough_memory(mm, pages, cap_sys_admin); 1238 } 1239 1240 /** 1241 * security_bprm_creds_for_exec() - Prepare the credentials for exec() 1242 * @bprm: binary program information 1243 * 1244 * If the setup in prepare_exec_creds did not setup @bprm->cred->security 1245 * properly for executing @bprm->file, update the LSM's portion of 1246 * @bprm->cred->security to be what commit_creds needs to install for the new 1247 * program. This hook may also optionally check permissions (e.g. for 1248 * transitions between security domains). The hook must set @bprm->secureexec 1249 * to 1 if AT_SECURE should be set to request libc enable secure mode. @bprm 1250 * contains the linux_binprm structure. 1251 * 1252 * Return: Returns 0 if the hook is successful and permission is granted. 1253 */ 1254 int security_bprm_creds_for_exec(struct linux_binprm *bprm) 1255 { 1256 return call_int_hook(bprm_creds_for_exec, bprm); 1257 } 1258 1259 /** 1260 * security_bprm_creds_from_file() - Update linux_binprm creds based on file 1261 * @bprm: binary program information 1262 * @file: associated file 1263 * 1264 * If @file is setpcap, suid, sgid or otherwise marked to change privilege upon 1265 * exec, update @bprm->cred to reflect that change. This is called after 1266 * finding the binary that will be executed without an interpreter. This 1267 * ensures that the credentials will not be derived from a script that the 1268 * binary will need to reopen, which when reopend may end up being a completely 1269 * different file. This hook may also optionally check permissions (e.g. for 1270 * transitions between security domains). The hook must set @bprm->secureexec 1271 * to 1 if AT_SECURE should be set to request libc enable secure mode. The 1272 * hook must add to @bprm->per_clear any personality flags that should be 1273 * cleared from current->personality. @bprm contains the linux_binprm 1274 * structure. 1275 * 1276 * Return: Returns 0 if the hook is successful and permission is granted. 1277 */ 1278 int security_bprm_creds_from_file(struct linux_binprm *bprm, const struct file *file) 1279 { 1280 return call_int_hook(bprm_creds_from_file, bprm, file); 1281 } 1282 1283 /** 1284 * security_bprm_check() - Mediate binary handler search 1285 * @bprm: binary program information 1286 * 1287 * This hook mediates the point when a search for a binary handler will begin. 1288 * It allows a check against the @bprm->cred->security value which was set in 1289 * the preceding creds_for_exec call. The argv list and envp list are reliably 1290 * available in @bprm. This hook may be called multiple times during a single 1291 * execve. @bprm contains the linux_binprm structure. 1292 * 1293 * Return: Returns 0 if the hook is successful and permission is granted. 1294 */ 1295 int security_bprm_check(struct linux_binprm *bprm) 1296 { 1297 return call_int_hook(bprm_check_security, bprm); 1298 } 1299 1300 /** 1301 * security_bprm_committing_creds() - Install creds for a process during exec() 1302 * @bprm: binary program information 1303 * 1304 * Prepare to install the new security attributes of a process being 1305 * transformed by an execve operation, based on the old credentials pointed to 1306 * by @current->cred and the information set in @bprm->cred by the 1307 * bprm_creds_for_exec hook. @bprm points to the linux_binprm structure. This 1308 * hook is a good place to perform state changes on the process such as closing 1309 * open file descriptors to which access will no longer be granted when the 1310 * attributes are changed. This is called immediately before commit_creds(). 1311 */ 1312 void security_bprm_committing_creds(const struct linux_binprm *bprm) 1313 { 1314 call_void_hook(bprm_committing_creds, bprm); 1315 } 1316 1317 /** 1318 * security_bprm_committed_creds() - Tidy up after cred install during exec() 1319 * @bprm: binary program information 1320 * 1321 * Tidy up after the installation of the new security attributes of a process 1322 * being transformed by an execve operation. The new credentials have, by this 1323 * point, been set to @current->cred. @bprm points to the linux_binprm 1324 * structure. This hook is a good place to perform state changes on the 1325 * process such as clearing out non-inheritable signal state. This is called 1326 * immediately after commit_creds(). 1327 */ 1328 void security_bprm_committed_creds(const struct linux_binprm *bprm) 1329 { 1330 call_void_hook(bprm_committed_creds, bprm); 1331 } 1332 1333 /** 1334 * security_fs_context_submount() - Initialise fc->security 1335 * @fc: new filesystem context 1336 * @reference: dentry reference for submount/remount 1337 * 1338 * Fill out the ->security field for a new fs_context. 1339 * 1340 * Return: Returns 0 on success or negative error code on failure. 1341 */ 1342 int security_fs_context_submount(struct fs_context *fc, struct super_block *reference) 1343 { 1344 return call_int_hook(fs_context_submount, fc, reference); 1345 } 1346 1347 /** 1348 * security_fs_context_dup() - Duplicate a fs_context LSM blob 1349 * @fc: destination filesystem context 1350 * @src_fc: source filesystem context 1351 * 1352 * Allocate and attach a security structure to sc->security. This pointer is 1353 * initialised to NULL by the caller. @fc indicates the new filesystem context. 1354 * @src_fc indicates the original filesystem context. 1355 * 1356 * Return: Returns 0 on success or a negative error code on failure. 1357 */ 1358 int security_fs_context_dup(struct fs_context *fc, struct fs_context *src_fc) 1359 { 1360 return call_int_hook(fs_context_dup, fc, src_fc); 1361 } 1362 1363 /** 1364 * security_fs_context_parse_param() - Configure a filesystem context 1365 * @fc: filesystem context 1366 * @param: filesystem parameter 1367 * 1368 * Userspace provided a parameter to configure a superblock. The LSM can 1369 * consume the parameter or return it to the caller for use elsewhere. 1370 * 1371 * Return: If the parameter is used by the LSM it should return 0, if it is 1372 * returned to the caller -ENOPARAM is returned, otherwise a negative 1373 * error code is returned. 1374 */ 1375 int security_fs_context_parse_param(struct fs_context *fc, 1376 struct fs_parameter *param) 1377 { 1378 struct lsm_static_call *scall; 1379 int trc; 1380 int rc = -ENOPARAM; 1381 1382 lsm_for_each_hook(scall, fs_context_parse_param) { 1383 trc = scall->hl->hook.fs_context_parse_param(fc, param); 1384 if (trc == 0) 1385 rc = 0; 1386 else if (trc != -ENOPARAM) 1387 return trc; 1388 } 1389 return rc; 1390 } 1391 1392 /** 1393 * security_sb_alloc() - Allocate a super_block LSM blob 1394 * @sb: filesystem superblock 1395 * 1396 * Allocate and attach a security structure to the sb->s_security field. The 1397 * s_security field is initialized to NULL when the structure is allocated. 1398 * @sb contains the super_block structure to be modified. 1399 * 1400 * Return: Returns 0 if operation was successful. 1401 */ 1402 int security_sb_alloc(struct super_block *sb) 1403 { 1404 int rc = lsm_superblock_alloc(sb); 1405 1406 if (unlikely(rc)) 1407 return rc; 1408 rc = call_int_hook(sb_alloc_security, sb); 1409 if (unlikely(rc)) 1410 security_sb_free(sb); 1411 return rc; 1412 } 1413 1414 /** 1415 * security_sb_delete() - Release super_block LSM associated objects 1416 * @sb: filesystem superblock 1417 * 1418 * Release objects tied to a superblock (e.g. inodes). @sb contains the 1419 * super_block structure being released. 1420 */ 1421 void security_sb_delete(struct super_block *sb) 1422 { 1423 call_void_hook(sb_delete, sb); 1424 } 1425 1426 /** 1427 * security_sb_free() - Free a super_block LSM blob 1428 * @sb: filesystem superblock 1429 * 1430 * Deallocate and clear the sb->s_security field. @sb contains the super_block 1431 * structure to be modified. 1432 */ 1433 void security_sb_free(struct super_block *sb) 1434 { 1435 call_void_hook(sb_free_security, sb); 1436 kfree(sb->s_security); 1437 sb->s_security = NULL; 1438 } 1439 1440 /** 1441 * security_free_mnt_opts() - Free memory associated with mount options 1442 * @mnt_opts: LSM processed mount options 1443 * 1444 * Free memory associated with @mnt_ops. 1445 */ 1446 void security_free_mnt_opts(void **mnt_opts) 1447 { 1448 if (!*mnt_opts) 1449 return; 1450 call_void_hook(sb_free_mnt_opts, *mnt_opts); 1451 *mnt_opts = NULL; 1452 } 1453 EXPORT_SYMBOL(security_free_mnt_opts); 1454 1455 /** 1456 * security_sb_eat_lsm_opts() - Consume LSM mount options 1457 * @options: mount options 1458 * @mnt_opts: LSM processed mount options 1459 * 1460 * Eat (scan @options) and save them in @mnt_opts. 1461 * 1462 * Return: Returns 0 on success, negative values on failure. 1463 */ 1464 int security_sb_eat_lsm_opts(char *options, void **mnt_opts) 1465 { 1466 return call_int_hook(sb_eat_lsm_opts, options, mnt_opts); 1467 } 1468 EXPORT_SYMBOL(security_sb_eat_lsm_opts); 1469 1470 /** 1471 * security_sb_mnt_opts_compat() - Check if new mount options are allowed 1472 * @sb: filesystem superblock 1473 * @mnt_opts: new mount options 1474 * 1475 * Determine if the new mount options in @mnt_opts are allowed given the 1476 * existing mounted filesystem at @sb. @sb superblock being compared. 1477 * 1478 * Return: Returns 0 if options are compatible. 1479 */ 1480 int security_sb_mnt_opts_compat(struct super_block *sb, 1481 void *mnt_opts) 1482 { 1483 return call_int_hook(sb_mnt_opts_compat, sb, mnt_opts); 1484 } 1485 EXPORT_SYMBOL(security_sb_mnt_opts_compat); 1486 1487 /** 1488 * security_sb_remount() - Verify no incompatible mount changes during remount 1489 * @sb: filesystem superblock 1490 * @mnt_opts: (re)mount options 1491 * 1492 * Extracts security system specific mount options and verifies no changes are 1493 * being made to those options. 1494 * 1495 * Return: Returns 0 if permission is granted. 1496 */ 1497 int security_sb_remount(struct super_block *sb, 1498 void *mnt_opts) 1499 { 1500 return call_int_hook(sb_remount, sb, mnt_opts); 1501 } 1502 EXPORT_SYMBOL(security_sb_remount); 1503 1504 /** 1505 * security_sb_kern_mount() - Check if a kernel mount is allowed 1506 * @sb: filesystem superblock 1507 * 1508 * Mount this @sb if allowed by permissions. 1509 * 1510 * Return: Returns 0 if permission is granted. 1511 */ 1512 int security_sb_kern_mount(const struct super_block *sb) 1513 { 1514 return call_int_hook(sb_kern_mount, sb); 1515 } 1516 1517 /** 1518 * security_sb_show_options() - Output the mount options for a superblock 1519 * @m: output file 1520 * @sb: filesystem superblock 1521 * 1522 * Show (print on @m) mount options for this @sb. 1523 * 1524 * Return: Returns 0 on success, negative values on failure. 1525 */ 1526 int security_sb_show_options(struct seq_file *m, struct super_block *sb) 1527 { 1528 return call_int_hook(sb_show_options, m, sb); 1529 } 1530 1531 /** 1532 * security_sb_statfs() - Check if accessing fs stats is allowed 1533 * @dentry: superblock handle 1534 * 1535 * Check permission before obtaining filesystem statistics for the @mnt 1536 * mountpoint. @dentry is a handle on the superblock for the filesystem. 1537 * 1538 * Return: Returns 0 if permission is granted. 1539 */ 1540 int security_sb_statfs(struct dentry *dentry) 1541 { 1542 return call_int_hook(sb_statfs, dentry); 1543 } 1544 1545 /** 1546 * security_sb_mount() - Check permission for mounting a filesystem 1547 * @dev_name: filesystem backing device 1548 * @path: mount point 1549 * @type: filesystem type 1550 * @flags: mount flags 1551 * @data: filesystem specific data 1552 * 1553 * Check permission before an object specified by @dev_name is mounted on the 1554 * mount point named by @nd. For an ordinary mount, @dev_name identifies a 1555 * device if the file system type requires a device. For a remount 1556 * (@flags & MS_REMOUNT), @dev_name is irrelevant. For a loopback/bind mount 1557 * (@flags & MS_BIND), @dev_name identifies the pathname of the object being 1558 * mounted. 1559 * 1560 * Return: Returns 0 if permission is granted. 1561 */ 1562 int security_sb_mount(const char *dev_name, const struct path *path, 1563 const char *type, unsigned long flags, void *data) 1564 { 1565 return call_int_hook(sb_mount, dev_name, path, type, flags, data); 1566 } 1567 1568 /** 1569 * security_sb_umount() - Check permission for unmounting a filesystem 1570 * @mnt: mounted filesystem 1571 * @flags: unmount flags 1572 * 1573 * Check permission before the @mnt file system is unmounted. 1574 * 1575 * Return: Returns 0 if permission is granted. 1576 */ 1577 int security_sb_umount(struct vfsmount *mnt, int flags) 1578 { 1579 return call_int_hook(sb_umount, mnt, flags); 1580 } 1581 1582 /** 1583 * security_sb_pivotroot() - Check permissions for pivoting the rootfs 1584 * @old_path: new location for current rootfs 1585 * @new_path: location of the new rootfs 1586 * 1587 * Check permission before pivoting the root filesystem. 1588 * 1589 * Return: Returns 0 if permission is granted. 1590 */ 1591 int security_sb_pivotroot(const struct path *old_path, 1592 const struct path *new_path) 1593 { 1594 return call_int_hook(sb_pivotroot, old_path, new_path); 1595 } 1596 1597 /** 1598 * security_sb_set_mnt_opts() - Set the mount options for a filesystem 1599 * @sb: filesystem superblock 1600 * @mnt_opts: binary mount options 1601 * @kern_flags: kernel flags (in) 1602 * @set_kern_flags: kernel flags (out) 1603 * 1604 * Set the security relevant mount options used for a superblock. 1605 * 1606 * Return: Returns 0 on success, error on failure. 1607 */ 1608 int security_sb_set_mnt_opts(struct super_block *sb, 1609 void *mnt_opts, 1610 unsigned long kern_flags, 1611 unsigned long *set_kern_flags) 1612 { 1613 struct lsm_static_call *scall; 1614 int rc = mnt_opts ? -EOPNOTSUPP : LSM_RET_DEFAULT(sb_set_mnt_opts); 1615 1616 lsm_for_each_hook(scall, sb_set_mnt_opts) { 1617 rc = scall->hl->hook.sb_set_mnt_opts(sb, mnt_opts, kern_flags, 1618 set_kern_flags); 1619 if (rc != LSM_RET_DEFAULT(sb_set_mnt_opts)) 1620 break; 1621 } 1622 return rc; 1623 } 1624 EXPORT_SYMBOL(security_sb_set_mnt_opts); 1625 1626 /** 1627 * security_sb_clone_mnt_opts() - Duplicate superblock mount options 1628 * @oldsb: source superblock 1629 * @newsb: destination superblock 1630 * @kern_flags: kernel flags (in) 1631 * @set_kern_flags: kernel flags (out) 1632 * 1633 * Copy all security options from a given superblock to another. 1634 * 1635 * Return: Returns 0 on success, error on failure. 1636 */ 1637 int security_sb_clone_mnt_opts(const struct super_block *oldsb, 1638 struct super_block *newsb, 1639 unsigned long kern_flags, 1640 unsigned long *set_kern_flags) 1641 { 1642 return call_int_hook(sb_clone_mnt_opts, oldsb, newsb, 1643 kern_flags, set_kern_flags); 1644 } 1645 EXPORT_SYMBOL(security_sb_clone_mnt_opts); 1646 1647 /** 1648 * security_move_mount() - Check permissions for moving a mount 1649 * @from_path: source mount point 1650 * @to_path: destination mount point 1651 * 1652 * Check permission before a mount is moved. 1653 * 1654 * Return: Returns 0 if permission is granted. 1655 */ 1656 int security_move_mount(const struct path *from_path, 1657 const struct path *to_path) 1658 { 1659 return call_int_hook(move_mount, from_path, to_path); 1660 } 1661 1662 /** 1663 * security_path_notify() - Check if setting a watch is allowed 1664 * @path: file path 1665 * @mask: event mask 1666 * @obj_type: file path type 1667 * 1668 * Check permissions before setting a watch on events as defined by @mask, on 1669 * an object at @path, whose type is defined by @obj_type. 1670 * 1671 * Return: Returns 0 if permission is granted. 1672 */ 1673 int security_path_notify(const struct path *path, u64 mask, 1674 unsigned int obj_type) 1675 { 1676 return call_int_hook(path_notify, path, mask, obj_type); 1677 } 1678 1679 /** 1680 * security_inode_alloc() - Allocate an inode LSM blob 1681 * @inode: the inode 1682 * @gfp: allocation flags 1683 * 1684 * Allocate and attach a security structure to @inode->i_security. The 1685 * i_security field is initialized to NULL when the inode structure is 1686 * allocated. 1687 * 1688 * Return: Return 0 if operation was successful. 1689 */ 1690 int security_inode_alloc(struct inode *inode, gfp_t gfp) 1691 { 1692 int rc = lsm_inode_alloc(inode, gfp); 1693 1694 if (unlikely(rc)) 1695 return rc; 1696 rc = call_int_hook(inode_alloc_security, inode); 1697 if (unlikely(rc)) 1698 security_inode_free(inode); 1699 return rc; 1700 } 1701 1702 static void inode_free_by_rcu(struct rcu_head *head) 1703 { 1704 /* The rcu head is at the start of the inode blob */ 1705 call_void_hook(inode_free_security_rcu, head); 1706 kmem_cache_free(lsm_inode_cache, head); 1707 } 1708 1709 /** 1710 * security_inode_free() - Free an inode's LSM blob 1711 * @inode: the inode 1712 * 1713 * Release any LSM resources associated with @inode, although due to the 1714 * inode's RCU protections it is possible that the resources will not be 1715 * fully released until after the current RCU grace period has elapsed. 1716 * 1717 * It is important for LSMs to note that despite being present in a call to 1718 * security_inode_free(), @inode may still be referenced in a VFS path walk 1719 * and calls to security_inode_permission() may be made during, or after, 1720 * a call to security_inode_free(). For this reason the inode->i_security 1721 * field is released via a call_rcu() callback and any LSMs which need to 1722 * retain inode state for use in security_inode_permission() should only 1723 * release that state in the inode_free_security_rcu() LSM hook callback. 1724 */ 1725 void security_inode_free(struct inode *inode) 1726 { 1727 call_void_hook(inode_free_security, inode); 1728 if (!inode->i_security) 1729 return; 1730 call_rcu((struct rcu_head *)inode->i_security, inode_free_by_rcu); 1731 } 1732 1733 /** 1734 * security_dentry_init_security() - Perform dentry initialization 1735 * @dentry: the dentry to initialize 1736 * @mode: mode used to determine resource type 1737 * @name: name of the last path component 1738 * @xattr_name: name of the security/LSM xattr 1739 * @ctx: pointer to the resulting LSM context 1740 * @ctxlen: length of @ctx 1741 * 1742 * Compute a context for a dentry as the inode is not yet available since NFSv4 1743 * has no label backed by an EA anyway. It is important to note that 1744 * @xattr_name does not need to be free'd by the caller, it is a static string. 1745 * 1746 * Return: Returns 0 on success, negative values on failure. 1747 */ 1748 int security_dentry_init_security(struct dentry *dentry, int mode, 1749 const struct qstr *name, 1750 const char **xattr_name, void **ctx, 1751 u32 *ctxlen) 1752 { 1753 return call_int_hook(dentry_init_security, dentry, mode, name, 1754 xattr_name, ctx, ctxlen); 1755 } 1756 EXPORT_SYMBOL(security_dentry_init_security); 1757 1758 /** 1759 * security_dentry_create_files_as() - Perform dentry initialization 1760 * @dentry: the dentry to initialize 1761 * @mode: mode used to determine resource type 1762 * @name: name of the last path component 1763 * @old: creds to use for LSM context calculations 1764 * @new: creds to modify 1765 * 1766 * Compute a context for a dentry as the inode is not yet available and set 1767 * that context in passed in creds so that new files are created using that 1768 * context. Context is calculated using the passed in creds and not the creds 1769 * of the caller. 1770 * 1771 * Return: Returns 0 on success, error on failure. 1772 */ 1773 int security_dentry_create_files_as(struct dentry *dentry, int mode, 1774 struct qstr *name, 1775 const struct cred *old, struct cred *new) 1776 { 1777 return call_int_hook(dentry_create_files_as, dentry, mode, 1778 name, old, new); 1779 } 1780 EXPORT_SYMBOL(security_dentry_create_files_as); 1781 1782 /** 1783 * security_inode_init_security() - Initialize an inode's LSM context 1784 * @inode: the inode 1785 * @dir: parent directory 1786 * @qstr: last component of the pathname 1787 * @initxattrs: callback function to write xattrs 1788 * @fs_data: filesystem specific data 1789 * 1790 * Obtain the security attribute name suffix and value to set on a newly 1791 * created inode and set up the incore security field for the new inode. This 1792 * hook is called by the fs code as part of the inode creation transaction and 1793 * provides for atomic labeling of the inode, unlike the post_create/mkdir/... 1794 * hooks called by the VFS. 1795 * 1796 * The hook function is expected to populate the xattrs array, by calling 1797 * lsm_get_xattr_slot() to retrieve the slots reserved by the security module 1798 * with the lbs_xattr_count field of the lsm_blob_sizes structure. For each 1799 * slot, the hook function should set ->name to the attribute name suffix 1800 * (e.g. selinux), to allocate ->value (will be freed by the caller) and set it 1801 * to the attribute value, to set ->value_len to the length of the value. If 1802 * the security module does not use security attributes or does not wish to put 1803 * a security attribute on this particular inode, then it should return 1804 * -EOPNOTSUPP to skip this processing. 1805 * 1806 * Return: Returns 0 if the LSM successfully initialized all of the inode 1807 * security attributes that are required, negative values otherwise. 1808 */ 1809 int security_inode_init_security(struct inode *inode, struct inode *dir, 1810 const struct qstr *qstr, 1811 const initxattrs initxattrs, void *fs_data) 1812 { 1813 struct lsm_static_call *scall; 1814 struct xattr *new_xattrs = NULL; 1815 int ret = -EOPNOTSUPP, xattr_count = 0; 1816 1817 if (unlikely(IS_PRIVATE(inode))) 1818 return 0; 1819 1820 if (!blob_sizes.lbs_xattr_count) 1821 return 0; 1822 1823 if (initxattrs) { 1824 /* Allocate +1 as terminator. */ 1825 new_xattrs = kcalloc(blob_sizes.lbs_xattr_count + 1, 1826 sizeof(*new_xattrs), GFP_NOFS); 1827 if (!new_xattrs) 1828 return -ENOMEM; 1829 } 1830 1831 lsm_for_each_hook(scall, inode_init_security) { 1832 ret = scall->hl->hook.inode_init_security(inode, dir, qstr, new_xattrs, 1833 &xattr_count); 1834 if (ret && ret != -EOPNOTSUPP) 1835 goto out; 1836 /* 1837 * As documented in lsm_hooks.h, -EOPNOTSUPP in this context 1838 * means that the LSM is not willing to provide an xattr, not 1839 * that it wants to signal an error. Thus, continue to invoke 1840 * the remaining LSMs. 1841 */ 1842 } 1843 1844 /* If initxattrs() is NULL, xattr_count is zero, skip the call. */ 1845 if (!xattr_count) 1846 goto out; 1847 1848 ret = initxattrs(inode, new_xattrs, fs_data); 1849 out: 1850 for (; xattr_count > 0; xattr_count--) 1851 kfree(new_xattrs[xattr_count - 1].value); 1852 kfree(new_xattrs); 1853 return (ret == -EOPNOTSUPP) ? 0 : ret; 1854 } 1855 EXPORT_SYMBOL(security_inode_init_security); 1856 1857 /** 1858 * security_inode_init_security_anon() - Initialize an anonymous inode 1859 * @inode: the inode 1860 * @name: the anonymous inode class 1861 * @context_inode: an optional related inode 1862 * 1863 * Set up the incore security field for the new anonymous inode and return 1864 * whether the inode creation is permitted by the security module or not. 1865 * 1866 * Return: Returns 0 on success, -EACCES if the security module denies the 1867 * creation of this inode, or another -errno upon other errors. 1868 */ 1869 int security_inode_init_security_anon(struct inode *inode, 1870 const struct qstr *name, 1871 const struct inode *context_inode) 1872 { 1873 return call_int_hook(inode_init_security_anon, inode, name, 1874 context_inode); 1875 } 1876 1877 #ifdef CONFIG_SECURITY_PATH 1878 /** 1879 * security_path_mknod() - Check if creating a special file is allowed 1880 * @dir: parent directory 1881 * @dentry: new file 1882 * @mode: new file mode 1883 * @dev: device number 1884 * 1885 * Check permissions when creating a file. Note that this hook is called even 1886 * if mknod operation is being done for a regular file. 1887 * 1888 * Return: Returns 0 if permission is granted. 1889 */ 1890 int security_path_mknod(const struct path *dir, struct dentry *dentry, 1891 umode_t mode, unsigned int dev) 1892 { 1893 if (unlikely(IS_PRIVATE(d_backing_inode(dir->dentry)))) 1894 return 0; 1895 return call_int_hook(path_mknod, dir, dentry, mode, dev); 1896 } 1897 EXPORT_SYMBOL(security_path_mknod); 1898 1899 /** 1900 * security_path_post_mknod() - Update inode security after reg file creation 1901 * @idmap: idmap of the mount 1902 * @dentry: new file 1903 * 1904 * Update inode security field after a regular file has been created. 1905 */ 1906 void security_path_post_mknod(struct mnt_idmap *idmap, struct dentry *dentry) 1907 { 1908 if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) 1909 return; 1910 call_void_hook(path_post_mknod, idmap, dentry); 1911 } 1912 1913 /** 1914 * security_path_mkdir() - Check if creating a new directory is allowed 1915 * @dir: parent directory 1916 * @dentry: new directory 1917 * @mode: new directory mode 1918 * 1919 * Check permissions to create a new directory in the existing directory. 1920 * 1921 * Return: Returns 0 if permission is granted. 1922 */ 1923 int security_path_mkdir(const struct path *dir, struct dentry *dentry, 1924 umode_t mode) 1925 { 1926 if (unlikely(IS_PRIVATE(d_backing_inode(dir->dentry)))) 1927 return 0; 1928 return call_int_hook(path_mkdir, dir, dentry, mode); 1929 } 1930 EXPORT_SYMBOL(security_path_mkdir); 1931 1932 /** 1933 * security_path_rmdir() - Check if removing a directory is allowed 1934 * @dir: parent directory 1935 * @dentry: directory to remove 1936 * 1937 * Check the permission to remove a directory. 1938 * 1939 * Return: Returns 0 if permission is granted. 1940 */ 1941 int security_path_rmdir(const struct path *dir, struct dentry *dentry) 1942 { 1943 if (unlikely(IS_PRIVATE(d_backing_inode(dir->dentry)))) 1944 return 0; 1945 return call_int_hook(path_rmdir, dir, dentry); 1946 } 1947 1948 /** 1949 * security_path_unlink() - Check if removing a hard link is allowed 1950 * @dir: parent directory 1951 * @dentry: file 1952 * 1953 * Check the permission to remove a hard link to a file. 1954 * 1955 * Return: Returns 0 if permission is granted. 1956 */ 1957 int security_path_unlink(const struct path *dir, struct dentry *dentry) 1958 { 1959 if (unlikely(IS_PRIVATE(d_backing_inode(dir->dentry)))) 1960 return 0; 1961 return call_int_hook(path_unlink, dir, dentry); 1962 } 1963 EXPORT_SYMBOL(security_path_unlink); 1964 1965 /** 1966 * security_path_symlink() - Check if creating a symbolic link is allowed 1967 * @dir: parent directory 1968 * @dentry: symbolic link 1969 * @old_name: file pathname 1970 * 1971 * Check the permission to create a symbolic link to a file. 1972 * 1973 * Return: Returns 0 if permission is granted. 1974 */ 1975 int security_path_symlink(const struct path *dir, struct dentry *dentry, 1976 const char *old_name) 1977 { 1978 if (unlikely(IS_PRIVATE(d_backing_inode(dir->dentry)))) 1979 return 0; 1980 return call_int_hook(path_symlink, dir, dentry, old_name); 1981 } 1982 1983 /** 1984 * security_path_link - Check if creating a hard link is allowed 1985 * @old_dentry: existing file 1986 * @new_dir: new parent directory 1987 * @new_dentry: new link 1988 * 1989 * Check permission before creating a new hard link to a file. 1990 * 1991 * Return: Returns 0 if permission is granted. 1992 */ 1993 int security_path_link(struct dentry *old_dentry, const struct path *new_dir, 1994 struct dentry *new_dentry) 1995 { 1996 if (unlikely(IS_PRIVATE(d_backing_inode(old_dentry)))) 1997 return 0; 1998 return call_int_hook(path_link, old_dentry, new_dir, new_dentry); 1999 } 2000 2001 /** 2002 * security_path_rename() - Check if renaming a file is allowed 2003 * @old_dir: parent directory of the old file 2004 * @old_dentry: the old file 2005 * @new_dir: parent directory of the new file 2006 * @new_dentry: the new file 2007 * @flags: flags 2008 * 2009 * Check for permission to rename a file or directory. 2010 * 2011 * Return: Returns 0 if permission is granted. 2012 */ 2013 int security_path_rename(const struct path *old_dir, struct dentry *old_dentry, 2014 const struct path *new_dir, struct dentry *new_dentry, 2015 unsigned int flags) 2016 { 2017 if (unlikely(IS_PRIVATE(d_backing_inode(old_dentry)) || 2018 (d_is_positive(new_dentry) && 2019 IS_PRIVATE(d_backing_inode(new_dentry))))) 2020 return 0; 2021 2022 return call_int_hook(path_rename, old_dir, old_dentry, new_dir, 2023 new_dentry, flags); 2024 } 2025 EXPORT_SYMBOL(security_path_rename); 2026 2027 /** 2028 * security_path_truncate() - Check if truncating a file is allowed 2029 * @path: file 2030 * 2031 * Check permission before truncating the file indicated by path. Note that 2032 * truncation permissions may also be checked based on already opened files, 2033 * using the security_file_truncate() hook. 2034 * 2035 * Return: Returns 0 if permission is granted. 2036 */ 2037 int security_path_truncate(const struct path *path) 2038 { 2039 if (unlikely(IS_PRIVATE(d_backing_inode(path->dentry)))) 2040 return 0; 2041 return call_int_hook(path_truncate, path); 2042 } 2043 2044 /** 2045 * security_path_chmod() - Check if changing the file's mode is allowed 2046 * @path: file 2047 * @mode: new mode 2048 * 2049 * Check for permission to change a mode of the file @path. The new mode is 2050 * specified in @mode which is a bitmask of constants from 2051 * <include/uapi/linux/stat.h>. 2052 * 2053 * Return: Returns 0 if permission is granted. 2054 */ 2055 int security_path_chmod(const struct path *path, umode_t mode) 2056 { 2057 if (unlikely(IS_PRIVATE(d_backing_inode(path->dentry)))) 2058 return 0; 2059 return call_int_hook(path_chmod, path, mode); 2060 } 2061 2062 /** 2063 * security_path_chown() - Check if changing the file's owner/group is allowed 2064 * @path: file 2065 * @uid: file owner 2066 * @gid: file group 2067 * 2068 * Check for permission to change owner/group of a file or directory. 2069 * 2070 * Return: Returns 0 if permission is granted. 2071 */ 2072 int security_path_chown(const struct path *path, kuid_t uid, kgid_t gid) 2073 { 2074 if (unlikely(IS_PRIVATE(d_backing_inode(path->dentry)))) 2075 return 0; 2076 return call_int_hook(path_chown, path, uid, gid); 2077 } 2078 2079 /** 2080 * security_path_chroot() - Check if changing the root directory is allowed 2081 * @path: directory 2082 * 2083 * Check for permission to change root directory. 2084 * 2085 * Return: Returns 0 if permission is granted. 2086 */ 2087 int security_path_chroot(const struct path *path) 2088 { 2089 return call_int_hook(path_chroot, path); 2090 } 2091 #endif /* CONFIG_SECURITY_PATH */ 2092 2093 /** 2094 * security_inode_create() - Check if creating a file is allowed 2095 * @dir: the parent directory 2096 * @dentry: the file being created 2097 * @mode: requested file mode 2098 * 2099 * Check permission to create a regular file. 2100 * 2101 * Return: Returns 0 if permission is granted. 2102 */ 2103 int security_inode_create(struct inode *dir, struct dentry *dentry, 2104 umode_t mode) 2105 { 2106 if (unlikely(IS_PRIVATE(dir))) 2107 return 0; 2108 return call_int_hook(inode_create, dir, dentry, mode); 2109 } 2110 EXPORT_SYMBOL_GPL(security_inode_create); 2111 2112 /** 2113 * security_inode_post_create_tmpfile() - Update inode security of new tmpfile 2114 * @idmap: idmap of the mount 2115 * @inode: inode of the new tmpfile 2116 * 2117 * Update inode security data after a tmpfile has been created. 2118 */ 2119 void security_inode_post_create_tmpfile(struct mnt_idmap *idmap, 2120 struct inode *inode) 2121 { 2122 if (unlikely(IS_PRIVATE(inode))) 2123 return; 2124 call_void_hook(inode_post_create_tmpfile, idmap, inode); 2125 } 2126 2127 /** 2128 * security_inode_link() - Check if creating a hard link is allowed 2129 * @old_dentry: existing file 2130 * @dir: new parent directory 2131 * @new_dentry: new link 2132 * 2133 * Check permission before creating a new hard link to a file. 2134 * 2135 * Return: Returns 0 if permission is granted. 2136 */ 2137 int security_inode_link(struct dentry *old_dentry, struct inode *dir, 2138 struct dentry *new_dentry) 2139 { 2140 if (unlikely(IS_PRIVATE(d_backing_inode(old_dentry)))) 2141 return 0; 2142 return call_int_hook(inode_link, old_dentry, dir, new_dentry); 2143 } 2144 2145 /** 2146 * security_inode_unlink() - Check if removing a hard link is allowed 2147 * @dir: parent directory 2148 * @dentry: file 2149 * 2150 * Check the permission to remove a hard link to a file. 2151 * 2152 * Return: Returns 0 if permission is granted. 2153 */ 2154 int security_inode_unlink(struct inode *dir, struct dentry *dentry) 2155 { 2156 if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) 2157 return 0; 2158 return call_int_hook(inode_unlink, dir, dentry); 2159 } 2160 2161 /** 2162 * security_inode_symlink() - Check if creating a symbolic link is allowed 2163 * @dir: parent directory 2164 * @dentry: symbolic link 2165 * @old_name: existing filename 2166 * 2167 * Check the permission to create a symbolic link to a file. 2168 * 2169 * Return: Returns 0 if permission is granted. 2170 */ 2171 int security_inode_symlink(struct inode *dir, struct dentry *dentry, 2172 const char *old_name) 2173 { 2174 if (unlikely(IS_PRIVATE(dir))) 2175 return 0; 2176 return call_int_hook(inode_symlink, dir, dentry, old_name); 2177 } 2178 2179 /** 2180 * security_inode_mkdir() - Check if creation a new director is allowed 2181 * @dir: parent directory 2182 * @dentry: new directory 2183 * @mode: new directory mode 2184 * 2185 * Check permissions to create a new directory in the existing directory 2186 * associated with inode structure @dir. 2187 * 2188 * Return: Returns 0 if permission is granted. 2189 */ 2190 int security_inode_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode) 2191 { 2192 if (unlikely(IS_PRIVATE(dir))) 2193 return 0; 2194 return call_int_hook(inode_mkdir, dir, dentry, mode); 2195 } 2196 EXPORT_SYMBOL_GPL(security_inode_mkdir); 2197 2198 /** 2199 * security_inode_rmdir() - Check if removing a directory is allowed 2200 * @dir: parent directory 2201 * @dentry: directory to be removed 2202 * 2203 * Check the permission to remove a directory. 2204 * 2205 * Return: Returns 0 if permission is granted. 2206 */ 2207 int security_inode_rmdir(struct inode *dir, struct dentry *dentry) 2208 { 2209 if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) 2210 return 0; 2211 return call_int_hook(inode_rmdir, dir, dentry); 2212 } 2213 2214 /** 2215 * security_inode_mknod() - Check if creating a special file is allowed 2216 * @dir: parent directory 2217 * @dentry: new file 2218 * @mode: new file mode 2219 * @dev: device number 2220 * 2221 * Check permissions when creating a special file (or a socket or a fifo file 2222 * created via the mknod system call). Note that if mknod operation is being 2223 * done for a regular file, then the create hook will be called and not this 2224 * hook. 2225 * 2226 * Return: Returns 0 if permission is granted. 2227 */ 2228 int security_inode_mknod(struct inode *dir, struct dentry *dentry, 2229 umode_t mode, dev_t dev) 2230 { 2231 if (unlikely(IS_PRIVATE(dir))) 2232 return 0; 2233 return call_int_hook(inode_mknod, dir, dentry, mode, dev); 2234 } 2235 2236 /** 2237 * security_inode_rename() - Check if renaming a file is allowed 2238 * @old_dir: parent directory of the old file 2239 * @old_dentry: the old file 2240 * @new_dir: parent directory of the new file 2241 * @new_dentry: the new file 2242 * @flags: flags 2243 * 2244 * Check for permission to rename a file or directory. 2245 * 2246 * Return: Returns 0 if permission is granted. 2247 */ 2248 int security_inode_rename(struct inode *old_dir, struct dentry *old_dentry, 2249 struct inode *new_dir, struct dentry *new_dentry, 2250 unsigned int flags) 2251 { 2252 if (unlikely(IS_PRIVATE(d_backing_inode(old_dentry)) || 2253 (d_is_positive(new_dentry) && 2254 IS_PRIVATE(d_backing_inode(new_dentry))))) 2255 return 0; 2256 2257 if (flags & RENAME_EXCHANGE) { 2258 int err = call_int_hook(inode_rename, new_dir, new_dentry, 2259 old_dir, old_dentry); 2260 if (err) 2261 return err; 2262 } 2263 2264 return call_int_hook(inode_rename, old_dir, old_dentry, 2265 new_dir, new_dentry); 2266 } 2267 2268 /** 2269 * security_inode_readlink() - Check if reading a symbolic link is allowed 2270 * @dentry: link 2271 * 2272 * Check the permission to read the symbolic link. 2273 * 2274 * Return: Returns 0 if permission is granted. 2275 */ 2276 int security_inode_readlink(struct dentry *dentry) 2277 { 2278 if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) 2279 return 0; 2280 return call_int_hook(inode_readlink, dentry); 2281 } 2282 2283 /** 2284 * security_inode_follow_link() - Check if following a symbolic link is allowed 2285 * @dentry: link dentry 2286 * @inode: link inode 2287 * @rcu: true if in RCU-walk mode 2288 * 2289 * Check permission to follow a symbolic link when looking up a pathname. If 2290 * @rcu is true, @inode is not stable. 2291 * 2292 * Return: Returns 0 if permission is granted. 2293 */ 2294 int security_inode_follow_link(struct dentry *dentry, struct inode *inode, 2295 bool rcu) 2296 { 2297 if (unlikely(IS_PRIVATE(inode))) 2298 return 0; 2299 return call_int_hook(inode_follow_link, dentry, inode, rcu); 2300 } 2301 2302 /** 2303 * security_inode_permission() - Check if accessing an inode is allowed 2304 * @inode: inode 2305 * @mask: access mask 2306 * 2307 * Check permission before accessing an inode. This hook is called by the 2308 * existing Linux permission function, so a security module can use it to 2309 * provide additional checking for existing Linux permission checks. Notice 2310 * that this hook is called when a file is opened (as well as many other 2311 * operations), whereas the file_security_ops permission hook is called when 2312 * the actual read/write operations are performed. 2313 * 2314 * Return: Returns 0 if permission is granted. 2315 */ 2316 int security_inode_permission(struct inode *inode, int mask) 2317 { 2318 if (unlikely(IS_PRIVATE(inode))) 2319 return 0; 2320 return call_int_hook(inode_permission, inode, mask); 2321 } 2322 2323 /** 2324 * security_inode_setattr() - Check if setting file attributes is allowed 2325 * @idmap: idmap of the mount 2326 * @dentry: file 2327 * @attr: new attributes 2328 * 2329 * Check permission before setting file attributes. Note that the kernel call 2330 * to notify_change is performed from several locations, whenever file 2331 * attributes change (such as when a file is truncated, chown/chmod operations, 2332 * transferring disk quotas, etc). 2333 * 2334 * Return: Returns 0 if permission is granted. 2335 */ 2336 int security_inode_setattr(struct mnt_idmap *idmap, 2337 struct dentry *dentry, struct iattr *attr) 2338 { 2339 if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) 2340 return 0; 2341 return call_int_hook(inode_setattr, idmap, dentry, attr); 2342 } 2343 EXPORT_SYMBOL_GPL(security_inode_setattr); 2344 2345 /** 2346 * security_inode_post_setattr() - Update the inode after a setattr operation 2347 * @idmap: idmap of the mount 2348 * @dentry: file 2349 * @ia_valid: file attributes set 2350 * 2351 * Update inode security field after successful setting file attributes. 2352 */ 2353 void security_inode_post_setattr(struct mnt_idmap *idmap, struct dentry *dentry, 2354 int ia_valid) 2355 { 2356 if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) 2357 return; 2358 call_void_hook(inode_post_setattr, idmap, dentry, ia_valid); 2359 } 2360 2361 /** 2362 * security_inode_getattr() - Check if getting file attributes is allowed 2363 * @path: file 2364 * 2365 * Check permission before obtaining file attributes. 2366 * 2367 * Return: Returns 0 if permission is granted. 2368 */ 2369 int security_inode_getattr(const struct path *path) 2370 { 2371 if (unlikely(IS_PRIVATE(d_backing_inode(path->dentry)))) 2372 return 0; 2373 return call_int_hook(inode_getattr, path); 2374 } 2375 2376 /** 2377 * security_inode_setxattr() - Check if setting file xattrs is allowed 2378 * @idmap: idmap of the mount 2379 * @dentry: file 2380 * @name: xattr name 2381 * @value: xattr value 2382 * @size: size of xattr value 2383 * @flags: flags 2384 * 2385 * This hook performs the desired permission checks before setting the extended 2386 * attributes (xattrs) on @dentry. It is important to note that we have some 2387 * additional logic before the main LSM implementation calls to detect if we 2388 * need to perform an additional capability check at the LSM layer. 2389 * 2390 * Normally we enforce a capability check prior to executing the various LSM 2391 * hook implementations, but if a LSM wants to avoid this capability check, 2392 * it can register a 'inode_xattr_skipcap' hook and return a value of 1 for 2393 * xattrs that it wants to avoid the capability check, leaving the LSM fully 2394 * responsible for enforcing the access control for the specific xattr. If all 2395 * of the enabled LSMs refrain from registering a 'inode_xattr_skipcap' hook, 2396 * or return a 0 (the default return value), the capability check is still 2397 * performed. If no 'inode_xattr_skipcap' hooks are registered the capability 2398 * check is performed. 2399 * 2400 * Return: Returns 0 if permission is granted. 2401 */ 2402 int security_inode_setxattr(struct mnt_idmap *idmap, 2403 struct dentry *dentry, const char *name, 2404 const void *value, size_t size, int flags) 2405 { 2406 int rc; 2407 2408 if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) 2409 return 0; 2410 2411 /* enforce the capability checks at the lsm layer, if needed */ 2412 if (!call_int_hook(inode_xattr_skipcap, name)) { 2413 rc = cap_inode_setxattr(dentry, name, value, size, flags); 2414 if (rc) 2415 return rc; 2416 } 2417 2418 return call_int_hook(inode_setxattr, idmap, dentry, name, value, size, 2419 flags); 2420 } 2421 2422 /** 2423 * security_inode_set_acl() - Check if setting posix acls is allowed 2424 * @idmap: idmap of the mount 2425 * @dentry: file 2426 * @acl_name: acl name 2427 * @kacl: acl struct 2428 * 2429 * Check permission before setting posix acls, the posix acls in @kacl are 2430 * identified by @acl_name. 2431 * 2432 * Return: Returns 0 if permission is granted. 2433 */ 2434 int security_inode_set_acl(struct mnt_idmap *idmap, 2435 struct dentry *dentry, const char *acl_name, 2436 struct posix_acl *kacl) 2437 { 2438 if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) 2439 return 0; 2440 return call_int_hook(inode_set_acl, idmap, dentry, acl_name, kacl); 2441 } 2442 2443 /** 2444 * security_inode_post_set_acl() - Update inode security from posix acls set 2445 * @dentry: file 2446 * @acl_name: acl name 2447 * @kacl: acl struct 2448 * 2449 * Update inode security data after successfully setting posix acls on @dentry. 2450 * The posix acls in @kacl are identified by @acl_name. 2451 */ 2452 void security_inode_post_set_acl(struct dentry *dentry, const char *acl_name, 2453 struct posix_acl *kacl) 2454 { 2455 if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) 2456 return; 2457 call_void_hook(inode_post_set_acl, dentry, acl_name, kacl); 2458 } 2459 2460 /** 2461 * security_inode_get_acl() - Check if reading posix acls is allowed 2462 * @idmap: idmap of the mount 2463 * @dentry: file 2464 * @acl_name: acl name 2465 * 2466 * Check permission before getting osix acls, the posix acls are identified by 2467 * @acl_name. 2468 * 2469 * Return: Returns 0 if permission is granted. 2470 */ 2471 int security_inode_get_acl(struct mnt_idmap *idmap, 2472 struct dentry *dentry, const char *acl_name) 2473 { 2474 if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) 2475 return 0; 2476 return call_int_hook(inode_get_acl, idmap, dentry, acl_name); 2477 } 2478 2479 /** 2480 * security_inode_remove_acl() - Check if removing a posix acl is allowed 2481 * @idmap: idmap of the mount 2482 * @dentry: file 2483 * @acl_name: acl name 2484 * 2485 * Check permission before removing posix acls, the posix acls are identified 2486 * by @acl_name. 2487 * 2488 * Return: Returns 0 if permission is granted. 2489 */ 2490 int security_inode_remove_acl(struct mnt_idmap *idmap, 2491 struct dentry *dentry, const char *acl_name) 2492 { 2493 if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) 2494 return 0; 2495 return call_int_hook(inode_remove_acl, idmap, dentry, acl_name); 2496 } 2497 2498 /** 2499 * security_inode_post_remove_acl() - Update inode security after rm posix acls 2500 * @idmap: idmap of the mount 2501 * @dentry: file 2502 * @acl_name: acl name 2503 * 2504 * Update inode security data after successfully removing posix acls on 2505 * @dentry in @idmap. The posix acls are identified by @acl_name. 2506 */ 2507 void security_inode_post_remove_acl(struct mnt_idmap *idmap, 2508 struct dentry *dentry, const char *acl_name) 2509 { 2510 if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) 2511 return; 2512 call_void_hook(inode_post_remove_acl, idmap, dentry, acl_name); 2513 } 2514 2515 /** 2516 * security_inode_post_setxattr() - Update the inode after a setxattr operation 2517 * @dentry: file 2518 * @name: xattr name 2519 * @value: xattr value 2520 * @size: xattr value size 2521 * @flags: flags 2522 * 2523 * Update inode security field after successful setxattr operation. 2524 */ 2525 void security_inode_post_setxattr(struct dentry *dentry, const char *name, 2526 const void *value, size_t size, int flags) 2527 { 2528 if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) 2529 return; 2530 call_void_hook(inode_post_setxattr, dentry, name, value, size, flags); 2531 } 2532 2533 /** 2534 * security_inode_getxattr() - Check if xattr access is allowed 2535 * @dentry: file 2536 * @name: xattr name 2537 * 2538 * Check permission before obtaining the extended attributes identified by 2539 * @name for @dentry. 2540 * 2541 * Return: Returns 0 if permission is granted. 2542 */ 2543 int security_inode_getxattr(struct dentry *dentry, const char *name) 2544 { 2545 if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) 2546 return 0; 2547 return call_int_hook(inode_getxattr, dentry, name); 2548 } 2549 2550 /** 2551 * security_inode_listxattr() - Check if listing xattrs is allowed 2552 * @dentry: file 2553 * 2554 * Check permission before obtaining the list of extended attribute names for 2555 * @dentry. 2556 * 2557 * Return: Returns 0 if permission is granted. 2558 */ 2559 int security_inode_listxattr(struct dentry *dentry) 2560 { 2561 if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) 2562 return 0; 2563 return call_int_hook(inode_listxattr, dentry); 2564 } 2565 2566 /** 2567 * security_inode_removexattr() - Check if removing an xattr is allowed 2568 * @idmap: idmap of the mount 2569 * @dentry: file 2570 * @name: xattr name 2571 * 2572 * This hook performs the desired permission checks before setting the extended 2573 * attributes (xattrs) on @dentry. It is important to note that we have some 2574 * additional logic before the main LSM implementation calls to detect if we 2575 * need to perform an additional capability check at the LSM layer. 2576 * 2577 * Normally we enforce a capability check prior to executing the various LSM 2578 * hook implementations, but if a LSM wants to avoid this capability check, 2579 * it can register a 'inode_xattr_skipcap' hook and return a value of 1 for 2580 * xattrs that it wants to avoid the capability check, leaving the LSM fully 2581 * responsible for enforcing the access control for the specific xattr. If all 2582 * of the enabled LSMs refrain from registering a 'inode_xattr_skipcap' hook, 2583 * or return a 0 (the default return value), the capability check is still 2584 * performed. If no 'inode_xattr_skipcap' hooks are registered the capability 2585 * check is performed. 2586 * 2587 * Return: Returns 0 if permission is granted. 2588 */ 2589 int security_inode_removexattr(struct mnt_idmap *idmap, 2590 struct dentry *dentry, const char *name) 2591 { 2592 int rc; 2593 2594 if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) 2595 return 0; 2596 2597 /* enforce the capability checks at the lsm layer, if needed */ 2598 if (!call_int_hook(inode_xattr_skipcap, name)) { 2599 rc = cap_inode_removexattr(idmap, dentry, name); 2600 if (rc) 2601 return rc; 2602 } 2603 2604 return call_int_hook(inode_removexattr, idmap, dentry, name); 2605 } 2606 2607 /** 2608 * security_inode_post_removexattr() - Update the inode after a removexattr op 2609 * @dentry: file 2610 * @name: xattr name 2611 * 2612 * Update the inode after a successful removexattr operation. 2613 */ 2614 void security_inode_post_removexattr(struct dentry *dentry, const char *name) 2615 { 2616 if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) 2617 return; 2618 call_void_hook(inode_post_removexattr, dentry, name); 2619 } 2620 2621 /** 2622 * security_inode_need_killpriv() - Check if security_inode_killpriv() required 2623 * @dentry: associated dentry 2624 * 2625 * Called when an inode has been changed to determine if 2626 * security_inode_killpriv() should be called. 2627 * 2628 * Return: Return <0 on error to abort the inode change operation, return 0 if 2629 * security_inode_killpriv() does not need to be called, return >0 if 2630 * security_inode_killpriv() does need to be called. 2631 */ 2632 int security_inode_need_killpriv(struct dentry *dentry) 2633 { 2634 return call_int_hook(inode_need_killpriv, dentry); 2635 } 2636 2637 /** 2638 * security_inode_killpriv() - The setuid bit is removed, update LSM state 2639 * @idmap: idmap of the mount 2640 * @dentry: associated dentry 2641 * 2642 * The @dentry's setuid bit is being removed. Remove similar security labels. 2643 * Called with the dentry->d_inode->i_mutex held. 2644 * 2645 * Return: Return 0 on success. If error is returned, then the operation 2646 * causing setuid bit removal is failed. 2647 */ 2648 int security_inode_killpriv(struct mnt_idmap *idmap, 2649 struct dentry *dentry) 2650 { 2651 return call_int_hook(inode_killpriv, idmap, dentry); 2652 } 2653 2654 /** 2655 * security_inode_getsecurity() - Get the xattr security label of an inode 2656 * @idmap: idmap of the mount 2657 * @inode: inode 2658 * @name: xattr name 2659 * @buffer: security label buffer 2660 * @alloc: allocation flag 2661 * 2662 * Retrieve a copy of the extended attribute representation of the security 2663 * label associated with @name for @inode via @buffer. Note that @name is the 2664 * remainder of the attribute name after the security prefix has been removed. 2665 * @alloc is used to specify if the call should return a value via the buffer 2666 * or just the value length. 2667 * 2668 * Return: Returns size of buffer on success. 2669 */ 2670 int security_inode_getsecurity(struct mnt_idmap *idmap, 2671 struct inode *inode, const char *name, 2672 void **buffer, bool alloc) 2673 { 2674 if (unlikely(IS_PRIVATE(inode))) 2675 return LSM_RET_DEFAULT(inode_getsecurity); 2676 2677 return call_int_hook(inode_getsecurity, idmap, inode, name, buffer, 2678 alloc); 2679 } 2680 2681 /** 2682 * security_inode_setsecurity() - Set the xattr security label of an inode 2683 * @inode: inode 2684 * @name: xattr name 2685 * @value: security label 2686 * @size: length of security label 2687 * @flags: flags 2688 * 2689 * Set the security label associated with @name for @inode from the extended 2690 * attribute value @value. @size indicates the size of the @value in bytes. 2691 * @flags may be XATTR_CREATE, XATTR_REPLACE, or 0. Note that @name is the 2692 * remainder of the attribute name after the security. prefix has been removed. 2693 * 2694 * Return: Returns 0 on success. 2695 */ 2696 int security_inode_setsecurity(struct inode *inode, const char *name, 2697 const void *value, size_t size, int flags) 2698 { 2699 if (unlikely(IS_PRIVATE(inode))) 2700 return LSM_RET_DEFAULT(inode_setsecurity); 2701 2702 return call_int_hook(inode_setsecurity, inode, name, value, size, 2703 flags); 2704 } 2705 2706 /** 2707 * security_inode_listsecurity() - List the xattr security label names 2708 * @inode: inode 2709 * @buffer: buffer 2710 * @buffer_size: size of buffer 2711 * 2712 * Copy the extended attribute names for the security labels associated with 2713 * @inode into @buffer. The maximum size of @buffer is specified by 2714 * @buffer_size. @buffer may be NULL to request the size of the buffer 2715 * required. 2716 * 2717 * Return: Returns number of bytes used/required on success. 2718 */ 2719 int security_inode_listsecurity(struct inode *inode, 2720 char *buffer, size_t buffer_size) 2721 { 2722 if (unlikely(IS_PRIVATE(inode))) 2723 return 0; 2724 return call_int_hook(inode_listsecurity, inode, buffer, buffer_size); 2725 } 2726 EXPORT_SYMBOL(security_inode_listsecurity); 2727 2728 /** 2729 * security_inode_getsecid() - Get an inode's secid 2730 * @inode: inode 2731 * @secid: secid to return 2732 * 2733 * Get the secid associated with the node. In case of failure, @secid will be 2734 * set to zero. 2735 */ 2736 void security_inode_getsecid(struct inode *inode, u32 *secid) 2737 { 2738 call_void_hook(inode_getsecid, inode, secid); 2739 } 2740 2741 /** 2742 * security_inode_copy_up() - Create new creds for an overlayfs copy-up op 2743 * @src: union dentry of copy-up file 2744 * @new: newly created creds 2745 * 2746 * A file is about to be copied up from lower layer to upper layer of overlay 2747 * filesystem. Security module can prepare a set of new creds and modify as 2748 * need be and return new creds. Caller will switch to new creds temporarily to 2749 * create new file and release newly allocated creds. 2750 * 2751 * Return: Returns 0 on success or a negative error code on error. 2752 */ 2753 int security_inode_copy_up(struct dentry *src, struct cred **new) 2754 { 2755 return call_int_hook(inode_copy_up, src, new); 2756 } 2757 EXPORT_SYMBOL(security_inode_copy_up); 2758 2759 /** 2760 * security_inode_copy_up_xattr() - Filter xattrs in an overlayfs copy-up op 2761 * @src: union dentry of copy-up file 2762 * @name: xattr name 2763 * 2764 * Filter the xattrs being copied up when a unioned file is copied up from a 2765 * lower layer to the union/overlay layer. The caller is responsible for 2766 * reading and writing the xattrs, this hook is merely a filter. 2767 * 2768 * Return: Returns 0 to accept the xattr, -ECANCELED to discard the xattr, 2769 * -EOPNOTSUPP if the security module does not know about attribute, 2770 * or a negative error code to abort the copy up. 2771 */ 2772 int security_inode_copy_up_xattr(struct dentry *src, const char *name) 2773 { 2774 int rc; 2775 2776 rc = call_int_hook(inode_copy_up_xattr, src, name); 2777 if (rc != LSM_RET_DEFAULT(inode_copy_up_xattr)) 2778 return rc; 2779 2780 return LSM_RET_DEFAULT(inode_copy_up_xattr); 2781 } 2782 EXPORT_SYMBOL(security_inode_copy_up_xattr); 2783 2784 /** 2785 * security_inode_setintegrity() - Set the inode's integrity data 2786 * @inode: inode 2787 * @type: type of integrity, e.g. hash digest, signature, etc 2788 * @value: the integrity value 2789 * @size: size of the integrity value 2790 * 2791 * Register a verified integrity measurement of a inode with LSMs. 2792 * LSMs should free the previously saved data if @value is NULL. 2793 * 2794 * Return: Returns 0 on success, negative values on failure. 2795 */ 2796 int security_inode_setintegrity(const struct inode *inode, 2797 enum lsm_integrity_type type, const void *value, 2798 size_t size) 2799 { 2800 return call_int_hook(inode_setintegrity, inode, type, value, size); 2801 } 2802 EXPORT_SYMBOL(security_inode_setintegrity); 2803 2804 /** 2805 * security_kernfs_init_security() - Init LSM context for a kernfs node 2806 * @kn_dir: parent kernfs node 2807 * @kn: the kernfs node to initialize 2808 * 2809 * Initialize the security context of a newly created kernfs node based on its 2810 * own and its parent's attributes. 2811 * 2812 * Return: Returns 0 if permission is granted. 2813 */ 2814 int security_kernfs_init_security(struct kernfs_node *kn_dir, 2815 struct kernfs_node *kn) 2816 { 2817 return call_int_hook(kernfs_init_security, kn_dir, kn); 2818 } 2819 2820 /** 2821 * security_file_permission() - Check file permissions 2822 * @file: file 2823 * @mask: requested permissions 2824 * 2825 * Check file permissions before accessing an open file. This hook is called 2826 * by various operations that read or write files. A security module can use 2827 * this hook to perform additional checking on these operations, e.g. to 2828 * revalidate permissions on use to support privilege bracketing or policy 2829 * changes. Notice that this hook is used when the actual read/write 2830 * operations are performed, whereas the inode_security_ops hook is called when 2831 * a file is opened (as well as many other operations). Although this hook can 2832 * be used to revalidate permissions for various system call operations that 2833 * read or write files, it does not address the revalidation of permissions for 2834 * memory-mapped files. Security modules must handle this separately if they 2835 * need such revalidation. 2836 * 2837 * Return: Returns 0 if permission is granted. 2838 */ 2839 int security_file_permission(struct file *file, int mask) 2840 { 2841 return call_int_hook(file_permission, file, mask); 2842 } 2843 2844 /** 2845 * security_file_alloc() - Allocate and init a file's LSM blob 2846 * @file: the file 2847 * 2848 * Allocate and attach a security structure to the file->f_security field. The 2849 * security field is initialized to NULL when the structure is first created. 2850 * 2851 * Return: Return 0 if the hook is successful and permission is granted. 2852 */ 2853 int security_file_alloc(struct file *file) 2854 { 2855 int rc = lsm_file_alloc(file); 2856 2857 if (rc) 2858 return rc; 2859 rc = call_int_hook(file_alloc_security, file); 2860 if (unlikely(rc)) 2861 security_file_free(file); 2862 return rc; 2863 } 2864 2865 /** 2866 * security_file_release() - Perform actions before releasing the file ref 2867 * @file: the file 2868 * 2869 * Perform actions before releasing the last reference to a file. 2870 */ 2871 void security_file_release(struct file *file) 2872 { 2873 call_void_hook(file_release, file); 2874 } 2875 2876 /** 2877 * security_file_free() - Free a file's LSM blob 2878 * @file: the file 2879 * 2880 * Deallocate and free any security structures stored in file->f_security. 2881 */ 2882 void security_file_free(struct file *file) 2883 { 2884 void *blob; 2885 2886 call_void_hook(file_free_security, file); 2887 2888 blob = file->f_security; 2889 if (blob) { 2890 file->f_security = NULL; 2891 kmem_cache_free(lsm_file_cache, blob); 2892 } 2893 } 2894 2895 /** 2896 * security_file_ioctl() - Check if an ioctl is allowed 2897 * @file: associated file 2898 * @cmd: ioctl cmd 2899 * @arg: ioctl arguments 2900 * 2901 * Check permission for an ioctl operation on @file. Note that @arg sometimes 2902 * represents a user space pointer; in other cases, it may be a simple integer 2903 * value. When @arg represents a user space pointer, it should never be used 2904 * by the security module. 2905 * 2906 * Return: Returns 0 if permission is granted. 2907 */ 2908 int security_file_ioctl(struct file *file, unsigned int cmd, unsigned long arg) 2909 { 2910 return call_int_hook(file_ioctl, file, cmd, arg); 2911 } 2912 EXPORT_SYMBOL_GPL(security_file_ioctl); 2913 2914 /** 2915 * security_file_ioctl_compat() - Check if an ioctl is allowed in compat mode 2916 * @file: associated file 2917 * @cmd: ioctl cmd 2918 * @arg: ioctl arguments 2919 * 2920 * Compat version of security_file_ioctl() that correctly handles 32-bit 2921 * processes running on 64-bit kernels. 2922 * 2923 * Return: Returns 0 if permission is granted. 2924 */ 2925 int security_file_ioctl_compat(struct file *file, unsigned int cmd, 2926 unsigned long arg) 2927 { 2928 return call_int_hook(file_ioctl_compat, file, cmd, arg); 2929 } 2930 EXPORT_SYMBOL_GPL(security_file_ioctl_compat); 2931 2932 static inline unsigned long mmap_prot(struct file *file, unsigned long prot) 2933 { 2934 /* 2935 * Does we have PROT_READ and does the application expect 2936 * it to imply PROT_EXEC? If not, nothing to talk about... 2937 */ 2938 if ((prot & (PROT_READ | PROT_EXEC)) != PROT_READ) 2939 return prot; 2940 if (!(current->personality & READ_IMPLIES_EXEC)) 2941 return prot; 2942 /* 2943 * if that's an anonymous mapping, let it. 2944 */ 2945 if (!file) 2946 return prot | PROT_EXEC; 2947 /* 2948 * ditto if it's not on noexec mount, except that on !MMU we need 2949 * NOMMU_MAP_EXEC (== VM_MAYEXEC) in this case 2950 */ 2951 if (!path_noexec(&file->f_path)) { 2952 #ifndef CONFIG_MMU 2953 if (file->f_op->mmap_capabilities) { 2954 unsigned caps = file->f_op->mmap_capabilities(file); 2955 if (!(caps & NOMMU_MAP_EXEC)) 2956 return prot; 2957 } 2958 #endif 2959 return prot | PROT_EXEC; 2960 } 2961 /* anything on noexec mount won't get PROT_EXEC */ 2962 return prot; 2963 } 2964 2965 /** 2966 * security_mmap_file() - Check if mmap'ing a file is allowed 2967 * @file: file 2968 * @prot: protection applied by the kernel 2969 * @flags: flags 2970 * 2971 * Check permissions for a mmap operation. The @file may be NULL, e.g. if 2972 * mapping anonymous memory. 2973 * 2974 * Return: Returns 0 if permission is granted. 2975 */ 2976 int security_mmap_file(struct file *file, unsigned long prot, 2977 unsigned long flags) 2978 { 2979 return call_int_hook(mmap_file, file, prot, mmap_prot(file, prot), 2980 flags); 2981 } 2982 2983 /** 2984 * security_mmap_addr() - Check if mmap'ing an address is allowed 2985 * @addr: address 2986 * 2987 * Check permissions for a mmap operation at @addr. 2988 * 2989 * Return: Returns 0 if permission is granted. 2990 */ 2991 int security_mmap_addr(unsigned long addr) 2992 { 2993 return call_int_hook(mmap_addr, addr); 2994 } 2995 2996 /** 2997 * security_file_mprotect() - Check if changing memory protections is allowed 2998 * @vma: memory region 2999 * @reqprot: application requested protection 3000 * @prot: protection applied by the kernel 3001 * 3002 * Check permissions before changing memory access permissions. 3003 * 3004 * Return: Returns 0 if permission is granted. 3005 */ 3006 int security_file_mprotect(struct vm_area_struct *vma, unsigned long reqprot, 3007 unsigned long prot) 3008 { 3009 return call_int_hook(file_mprotect, vma, reqprot, prot); 3010 } 3011 3012 /** 3013 * security_file_lock() - Check if a file lock is allowed 3014 * @file: file 3015 * @cmd: lock operation (e.g. F_RDLCK, F_WRLCK) 3016 * 3017 * Check permission before performing file locking operations. Note the hook 3018 * mediates both flock and fcntl style locks. 3019 * 3020 * Return: Returns 0 if permission is granted. 3021 */ 3022 int security_file_lock(struct file *file, unsigned int cmd) 3023 { 3024 return call_int_hook(file_lock, file, cmd); 3025 } 3026 3027 /** 3028 * security_file_fcntl() - Check if fcntl() op is allowed 3029 * @file: file 3030 * @cmd: fcntl command 3031 * @arg: command argument 3032 * 3033 * Check permission before allowing the file operation specified by @cmd from 3034 * being performed on the file @file. Note that @arg sometimes represents a 3035 * user space pointer; in other cases, it may be a simple integer value. When 3036 * @arg represents a user space pointer, it should never be used by the 3037 * security module. 3038 * 3039 * Return: Returns 0 if permission is granted. 3040 */ 3041 int security_file_fcntl(struct file *file, unsigned int cmd, unsigned long arg) 3042 { 3043 return call_int_hook(file_fcntl, file, cmd, arg); 3044 } 3045 3046 /** 3047 * security_file_set_fowner() - Set the file owner info in the LSM blob 3048 * @file: the file 3049 * 3050 * Save owner security information (typically from current->security) in 3051 * file->f_security for later use by the send_sigiotask hook. 3052 * 3053 * This hook is called with file->f_owner.lock held. 3054 * 3055 * Return: Returns 0 on success. 3056 */ 3057 void security_file_set_fowner(struct file *file) 3058 { 3059 call_void_hook(file_set_fowner, file); 3060 } 3061 3062 /** 3063 * security_file_send_sigiotask() - Check if sending SIGIO/SIGURG is allowed 3064 * @tsk: target task 3065 * @fown: signal sender 3066 * @sig: signal to be sent, SIGIO is sent if 0 3067 * 3068 * Check permission for the file owner @fown to send SIGIO or SIGURG to the 3069 * process @tsk. Note that this hook is sometimes called from interrupt. Note 3070 * that the fown_struct, @fown, is never outside the context of a struct file, 3071 * so the file structure (and associated security information) can always be 3072 * obtained: container_of(fown, struct file, f_owner). 3073 * 3074 * Return: Returns 0 if permission is granted. 3075 */ 3076 int security_file_send_sigiotask(struct task_struct *tsk, 3077 struct fown_struct *fown, int sig) 3078 { 3079 return call_int_hook(file_send_sigiotask, tsk, fown, sig); 3080 } 3081 3082 /** 3083 * security_file_receive() - Check if receiving a file via IPC is allowed 3084 * @file: file being received 3085 * 3086 * This hook allows security modules to control the ability of a process to 3087 * receive an open file descriptor via socket IPC. 3088 * 3089 * Return: Returns 0 if permission is granted. 3090 */ 3091 int security_file_receive(struct file *file) 3092 { 3093 return call_int_hook(file_receive, file); 3094 } 3095 3096 /** 3097 * security_file_open() - Save open() time state for late use by the LSM 3098 * @file: 3099 * 3100 * Save open-time permission checking state for later use upon file_permission, 3101 * and recheck access if anything has changed since inode_permission. 3102 * 3103 * Return: Returns 0 if permission is granted. 3104 */ 3105 int security_file_open(struct file *file) 3106 { 3107 int ret; 3108 3109 ret = call_int_hook(file_open, file); 3110 if (ret) 3111 return ret; 3112 3113 return fsnotify_open_perm(file); 3114 } 3115 3116 /** 3117 * security_file_post_open() - Evaluate a file after it has been opened 3118 * @file: the file 3119 * @mask: access mask 3120 * 3121 * Evaluate an opened file and the access mask requested with open(). The hook 3122 * is useful for LSMs that require the file content to be available in order to 3123 * make decisions. 3124 * 3125 * Return: Returns 0 if permission is granted. 3126 */ 3127 int security_file_post_open(struct file *file, int mask) 3128 { 3129 return call_int_hook(file_post_open, file, mask); 3130 } 3131 EXPORT_SYMBOL_GPL(security_file_post_open); 3132 3133 /** 3134 * security_file_truncate() - Check if truncating a file is allowed 3135 * @file: file 3136 * 3137 * Check permission before truncating a file, i.e. using ftruncate. Note that 3138 * truncation permission may also be checked based on the path, using the 3139 * @path_truncate hook. 3140 * 3141 * Return: Returns 0 if permission is granted. 3142 */ 3143 int security_file_truncate(struct file *file) 3144 { 3145 return call_int_hook(file_truncate, file); 3146 } 3147 3148 /** 3149 * security_task_alloc() - Allocate a task's LSM blob 3150 * @task: the task 3151 * @clone_flags: flags indicating what is being shared 3152 * 3153 * Handle allocation of task-related resources. 3154 * 3155 * Return: Returns a zero on success, negative values on failure. 3156 */ 3157 int security_task_alloc(struct task_struct *task, unsigned long clone_flags) 3158 { 3159 int rc = lsm_task_alloc(task); 3160 3161 if (rc) 3162 return rc; 3163 rc = call_int_hook(task_alloc, task, clone_flags); 3164 if (unlikely(rc)) 3165 security_task_free(task); 3166 return rc; 3167 } 3168 3169 /** 3170 * security_task_free() - Free a task's LSM blob and related resources 3171 * @task: task 3172 * 3173 * Handle release of task-related resources. Note that this can be called from 3174 * interrupt context. 3175 */ 3176 void security_task_free(struct task_struct *task) 3177 { 3178 call_void_hook(task_free, task); 3179 3180 kfree(task->security); 3181 task->security = NULL; 3182 } 3183 3184 /** 3185 * security_cred_alloc_blank() - Allocate the min memory to allow cred_transfer 3186 * @cred: credentials 3187 * @gfp: gfp flags 3188 * 3189 * Only allocate sufficient memory and attach to @cred such that 3190 * cred_transfer() will not get ENOMEM. 3191 * 3192 * Return: Returns 0 on success, negative values on failure. 3193 */ 3194 int security_cred_alloc_blank(struct cred *cred, gfp_t gfp) 3195 { 3196 int rc = lsm_cred_alloc(cred, gfp); 3197 3198 if (rc) 3199 return rc; 3200 3201 rc = call_int_hook(cred_alloc_blank, cred, gfp); 3202 if (unlikely(rc)) 3203 security_cred_free(cred); 3204 return rc; 3205 } 3206 3207 /** 3208 * security_cred_free() - Free the cred's LSM blob and associated resources 3209 * @cred: credentials 3210 * 3211 * Deallocate and clear the cred->security field in a set of credentials. 3212 */ 3213 void security_cred_free(struct cred *cred) 3214 { 3215 /* 3216 * There is a failure case in prepare_creds() that 3217 * may result in a call here with ->security being NULL. 3218 */ 3219 if (unlikely(cred->security == NULL)) 3220 return; 3221 3222 call_void_hook(cred_free, cred); 3223 3224 kfree(cred->security); 3225 cred->security = NULL; 3226 } 3227 3228 /** 3229 * security_prepare_creds() - Prepare a new set of credentials 3230 * @new: new credentials 3231 * @old: original credentials 3232 * @gfp: gfp flags 3233 * 3234 * Prepare a new set of credentials by copying the data from the old set. 3235 * 3236 * Return: Returns 0 on success, negative values on failure. 3237 */ 3238 int security_prepare_creds(struct cred *new, const struct cred *old, gfp_t gfp) 3239 { 3240 int rc = lsm_cred_alloc(new, gfp); 3241 3242 if (rc) 3243 return rc; 3244 3245 rc = call_int_hook(cred_prepare, new, old, gfp); 3246 if (unlikely(rc)) 3247 security_cred_free(new); 3248 return rc; 3249 } 3250 3251 /** 3252 * security_transfer_creds() - Transfer creds 3253 * @new: target credentials 3254 * @old: original credentials 3255 * 3256 * Transfer data from original creds to new creds. 3257 */ 3258 void security_transfer_creds(struct cred *new, const struct cred *old) 3259 { 3260 call_void_hook(cred_transfer, new, old); 3261 } 3262 3263 /** 3264 * security_cred_getsecid() - Get the secid from a set of credentials 3265 * @c: credentials 3266 * @secid: secid value 3267 * 3268 * Retrieve the security identifier of the cred structure @c. In case of 3269 * failure, @secid will be set to zero. 3270 */ 3271 void security_cred_getsecid(const struct cred *c, u32 *secid) 3272 { 3273 *secid = 0; 3274 call_void_hook(cred_getsecid, c, secid); 3275 } 3276 EXPORT_SYMBOL(security_cred_getsecid); 3277 3278 /** 3279 * security_kernel_act_as() - Set the kernel credentials to act as secid 3280 * @new: credentials 3281 * @secid: secid 3282 * 3283 * Set the credentials for a kernel service to act as (subjective context). 3284 * The current task must be the one that nominated @secid. 3285 * 3286 * Return: Returns 0 if successful. 3287 */ 3288 int security_kernel_act_as(struct cred *new, u32 secid) 3289 { 3290 return call_int_hook(kernel_act_as, new, secid); 3291 } 3292 3293 /** 3294 * security_kernel_create_files_as() - Set file creation context using an inode 3295 * @new: target credentials 3296 * @inode: reference inode 3297 * 3298 * Set the file creation context in a set of credentials to be the same as the 3299 * objective context of the specified inode. The current task must be the one 3300 * that nominated @inode. 3301 * 3302 * Return: Returns 0 if successful. 3303 */ 3304 int security_kernel_create_files_as(struct cred *new, struct inode *inode) 3305 { 3306 return call_int_hook(kernel_create_files_as, new, inode); 3307 } 3308 3309 /** 3310 * security_kernel_module_request() - Check if loading a module is allowed 3311 * @kmod_name: module name 3312 * 3313 * Ability to trigger the kernel to automatically upcall to userspace for 3314 * userspace to load a kernel module with the given name. 3315 * 3316 * Return: Returns 0 if successful. 3317 */ 3318 int security_kernel_module_request(char *kmod_name) 3319 { 3320 return call_int_hook(kernel_module_request, kmod_name); 3321 } 3322 3323 /** 3324 * security_kernel_read_file() - Read a file specified by userspace 3325 * @file: file 3326 * @id: file identifier 3327 * @contents: trust if security_kernel_post_read_file() will be called 3328 * 3329 * Read a file specified by userspace. 3330 * 3331 * Return: Returns 0 if permission is granted. 3332 */ 3333 int security_kernel_read_file(struct file *file, enum kernel_read_file_id id, 3334 bool contents) 3335 { 3336 return call_int_hook(kernel_read_file, file, id, contents); 3337 } 3338 EXPORT_SYMBOL_GPL(security_kernel_read_file); 3339 3340 /** 3341 * security_kernel_post_read_file() - Read a file specified by userspace 3342 * @file: file 3343 * @buf: file contents 3344 * @size: size of file contents 3345 * @id: file identifier 3346 * 3347 * Read a file specified by userspace. This must be paired with a prior call 3348 * to security_kernel_read_file() call that indicated this hook would also be 3349 * called, see security_kernel_read_file() for more information. 3350 * 3351 * Return: Returns 0 if permission is granted. 3352 */ 3353 int security_kernel_post_read_file(struct file *file, char *buf, loff_t size, 3354 enum kernel_read_file_id id) 3355 { 3356 return call_int_hook(kernel_post_read_file, file, buf, size, id); 3357 } 3358 EXPORT_SYMBOL_GPL(security_kernel_post_read_file); 3359 3360 /** 3361 * security_kernel_load_data() - Load data provided by userspace 3362 * @id: data identifier 3363 * @contents: true if security_kernel_post_load_data() will be called 3364 * 3365 * Load data provided by userspace. 3366 * 3367 * Return: Returns 0 if permission is granted. 3368 */ 3369 int security_kernel_load_data(enum kernel_load_data_id id, bool contents) 3370 { 3371 return call_int_hook(kernel_load_data, id, contents); 3372 } 3373 EXPORT_SYMBOL_GPL(security_kernel_load_data); 3374 3375 /** 3376 * security_kernel_post_load_data() - Load userspace data from a non-file source 3377 * @buf: data 3378 * @size: size of data 3379 * @id: data identifier 3380 * @description: text description of data, specific to the id value 3381 * 3382 * Load data provided by a non-file source (usually userspace buffer). This 3383 * must be paired with a prior security_kernel_load_data() call that indicated 3384 * this hook would also be called, see security_kernel_load_data() for more 3385 * information. 3386 * 3387 * Return: Returns 0 if permission is granted. 3388 */ 3389 int security_kernel_post_load_data(char *buf, loff_t size, 3390 enum kernel_load_data_id id, 3391 char *description) 3392 { 3393 return call_int_hook(kernel_post_load_data, buf, size, id, description); 3394 } 3395 EXPORT_SYMBOL_GPL(security_kernel_post_load_data); 3396 3397 /** 3398 * security_task_fix_setuid() - Update LSM with new user id attributes 3399 * @new: updated credentials 3400 * @old: credentials being replaced 3401 * @flags: LSM_SETID_* flag values 3402 * 3403 * Update the module's state after setting one or more of the user identity 3404 * attributes of the current process. The @flags parameter indicates which of 3405 * the set*uid system calls invoked this hook. If @new is the set of 3406 * credentials that will be installed. Modifications should be made to this 3407 * rather than to @current->cred. 3408 * 3409 * Return: Returns 0 on success. 3410 */ 3411 int security_task_fix_setuid(struct cred *new, const struct cred *old, 3412 int flags) 3413 { 3414 return call_int_hook(task_fix_setuid, new, old, flags); 3415 } 3416 3417 /** 3418 * security_task_fix_setgid() - Update LSM with new group id attributes 3419 * @new: updated credentials 3420 * @old: credentials being replaced 3421 * @flags: LSM_SETID_* flag value 3422 * 3423 * Update the module's state after setting one or more of the group identity 3424 * attributes of the current process. The @flags parameter indicates which of 3425 * the set*gid system calls invoked this hook. @new is the set of credentials 3426 * that will be installed. Modifications should be made to this rather than to 3427 * @current->cred. 3428 * 3429 * Return: Returns 0 on success. 3430 */ 3431 int security_task_fix_setgid(struct cred *new, const struct cred *old, 3432 int flags) 3433 { 3434 return call_int_hook(task_fix_setgid, new, old, flags); 3435 } 3436 3437 /** 3438 * security_task_fix_setgroups() - Update LSM with new supplementary groups 3439 * @new: updated credentials 3440 * @old: credentials being replaced 3441 * 3442 * Update the module's state after setting the supplementary group identity 3443 * attributes of the current process. @new is the set of credentials that will 3444 * be installed. Modifications should be made to this rather than to 3445 * @current->cred. 3446 * 3447 * Return: Returns 0 on success. 3448 */ 3449 int security_task_fix_setgroups(struct cred *new, const struct cred *old) 3450 { 3451 return call_int_hook(task_fix_setgroups, new, old); 3452 } 3453 3454 /** 3455 * security_task_setpgid() - Check if setting the pgid is allowed 3456 * @p: task being modified 3457 * @pgid: new pgid 3458 * 3459 * Check permission before setting the process group identifier of the process 3460 * @p to @pgid. 3461 * 3462 * Return: Returns 0 if permission is granted. 3463 */ 3464 int security_task_setpgid(struct task_struct *p, pid_t pgid) 3465 { 3466 return call_int_hook(task_setpgid, p, pgid); 3467 } 3468 3469 /** 3470 * security_task_getpgid() - Check if getting the pgid is allowed 3471 * @p: task 3472 * 3473 * Check permission before getting the process group identifier of the process 3474 * @p. 3475 * 3476 * Return: Returns 0 if permission is granted. 3477 */ 3478 int security_task_getpgid(struct task_struct *p) 3479 { 3480 return call_int_hook(task_getpgid, p); 3481 } 3482 3483 /** 3484 * security_task_getsid() - Check if getting the session id is allowed 3485 * @p: task 3486 * 3487 * Check permission before getting the session identifier of the process @p. 3488 * 3489 * Return: Returns 0 if permission is granted. 3490 */ 3491 int security_task_getsid(struct task_struct *p) 3492 { 3493 return call_int_hook(task_getsid, p); 3494 } 3495 3496 /** 3497 * security_current_getsecid_subj() - Get the current task's subjective secid 3498 * @secid: secid value 3499 * 3500 * Retrieve the subjective security identifier of the current task and return 3501 * it in @secid. In case of failure, @secid will be set to zero. 3502 */ 3503 void security_current_getsecid_subj(u32 *secid) 3504 { 3505 *secid = 0; 3506 call_void_hook(current_getsecid_subj, secid); 3507 } 3508 EXPORT_SYMBOL(security_current_getsecid_subj); 3509 3510 /** 3511 * security_task_getsecid_obj() - Get a task's objective secid 3512 * @p: target task 3513 * @secid: secid value 3514 * 3515 * Retrieve the objective security identifier of the task_struct in @p and 3516 * return it in @secid. In case of failure, @secid will be set to zero. 3517 */ 3518 void security_task_getsecid_obj(struct task_struct *p, u32 *secid) 3519 { 3520 *secid = 0; 3521 call_void_hook(task_getsecid_obj, p, secid); 3522 } 3523 EXPORT_SYMBOL(security_task_getsecid_obj); 3524 3525 /** 3526 * security_task_setnice() - Check if setting a task's nice value is allowed 3527 * @p: target task 3528 * @nice: nice value 3529 * 3530 * Check permission before setting the nice value of @p to @nice. 3531 * 3532 * Return: Returns 0 if permission is granted. 3533 */ 3534 int security_task_setnice(struct task_struct *p, int nice) 3535 { 3536 return call_int_hook(task_setnice, p, nice); 3537 } 3538 3539 /** 3540 * security_task_setioprio() - Check if setting a task's ioprio is allowed 3541 * @p: target task 3542 * @ioprio: ioprio value 3543 * 3544 * Check permission before setting the ioprio value of @p to @ioprio. 3545 * 3546 * Return: Returns 0 if permission is granted. 3547 */ 3548 int security_task_setioprio(struct task_struct *p, int ioprio) 3549 { 3550 return call_int_hook(task_setioprio, p, ioprio); 3551 } 3552 3553 /** 3554 * security_task_getioprio() - Check if getting a task's ioprio is allowed 3555 * @p: task 3556 * 3557 * Check permission before getting the ioprio value of @p. 3558 * 3559 * Return: Returns 0 if permission is granted. 3560 */ 3561 int security_task_getioprio(struct task_struct *p) 3562 { 3563 return call_int_hook(task_getioprio, p); 3564 } 3565 3566 /** 3567 * security_task_prlimit() - Check if get/setting resources limits is allowed 3568 * @cred: current task credentials 3569 * @tcred: target task credentials 3570 * @flags: LSM_PRLIMIT_* flag bits indicating a get/set/both 3571 * 3572 * Check permission before getting and/or setting the resource limits of 3573 * another task. 3574 * 3575 * Return: Returns 0 if permission is granted. 3576 */ 3577 int security_task_prlimit(const struct cred *cred, const struct cred *tcred, 3578 unsigned int flags) 3579 { 3580 return call_int_hook(task_prlimit, cred, tcred, flags); 3581 } 3582 3583 /** 3584 * security_task_setrlimit() - Check if setting a new rlimit value is allowed 3585 * @p: target task's group leader 3586 * @resource: resource whose limit is being set 3587 * @new_rlim: new resource limit 3588 * 3589 * Check permission before setting the resource limits of process @p for 3590 * @resource to @new_rlim. The old resource limit values can be examined by 3591 * dereferencing (p->signal->rlim + resource). 3592 * 3593 * Return: Returns 0 if permission is granted. 3594 */ 3595 int security_task_setrlimit(struct task_struct *p, unsigned int resource, 3596 struct rlimit *new_rlim) 3597 { 3598 return call_int_hook(task_setrlimit, p, resource, new_rlim); 3599 } 3600 3601 /** 3602 * security_task_setscheduler() - Check if setting sched policy/param is allowed 3603 * @p: target task 3604 * 3605 * Check permission before setting scheduling policy and/or parameters of 3606 * process @p. 3607 * 3608 * Return: Returns 0 if permission is granted. 3609 */ 3610 int security_task_setscheduler(struct task_struct *p) 3611 { 3612 return call_int_hook(task_setscheduler, p); 3613 } 3614 3615 /** 3616 * security_task_getscheduler() - Check if getting scheduling info is allowed 3617 * @p: target task 3618 * 3619 * Check permission before obtaining scheduling information for process @p. 3620 * 3621 * Return: Returns 0 if permission is granted. 3622 */ 3623 int security_task_getscheduler(struct task_struct *p) 3624 { 3625 return call_int_hook(task_getscheduler, p); 3626 } 3627 3628 /** 3629 * security_task_movememory() - Check if moving memory is allowed 3630 * @p: task 3631 * 3632 * Check permission before moving memory owned by process @p. 3633 * 3634 * Return: Returns 0 if permission is granted. 3635 */ 3636 int security_task_movememory(struct task_struct *p) 3637 { 3638 return call_int_hook(task_movememory, p); 3639 } 3640 3641 /** 3642 * security_task_kill() - Check if sending a signal is allowed 3643 * @p: target process 3644 * @info: signal information 3645 * @sig: signal value 3646 * @cred: credentials of the signal sender, NULL if @current 3647 * 3648 * Check permission before sending signal @sig to @p. @info can be NULL, the 3649 * constant 1, or a pointer to a kernel_siginfo structure. If @info is 1 or 3650 * SI_FROMKERNEL(info) is true, then the signal should be viewed as coming from 3651 * the kernel and should typically be permitted. SIGIO signals are handled 3652 * separately by the send_sigiotask hook in file_security_ops. 3653 * 3654 * Return: Returns 0 if permission is granted. 3655 */ 3656 int security_task_kill(struct task_struct *p, struct kernel_siginfo *info, 3657 int sig, const struct cred *cred) 3658 { 3659 return call_int_hook(task_kill, p, info, sig, cred); 3660 } 3661 3662 /** 3663 * security_task_prctl() - Check if a prctl op is allowed 3664 * @option: operation 3665 * @arg2: argument 3666 * @arg3: argument 3667 * @arg4: argument 3668 * @arg5: argument 3669 * 3670 * Check permission before performing a process control operation on the 3671 * current process. 3672 * 3673 * Return: Return -ENOSYS if no-one wanted to handle this op, any other value 3674 * to cause prctl() to return immediately with that value. 3675 */ 3676 int security_task_prctl(int option, unsigned long arg2, unsigned long arg3, 3677 unsigned long arg4, unsigned long arg5) 3678 { 3679 int thisrc; 3680 int rc = LSM_RET_DEFAULT(task_prctl); 3681 struct lsm_static_call *scall; 3682 3683 lsm_for_each_hook(scall, task_prctl) { 3684 thisrc = scall->hl->hook.task_prctl(option, arg2, arg3, arg4, arg5); 3685 if (thisrc != LSM_RET_DEFAULT(task_prctl)) { 3686 rc = thisrc; 3687 if (thisrc != 0) 3688 break; 3689 } 3690 } 3691 return rc; 3692 } 3693 3694 /** 3695 * security_task_to_inode() - Set the security attributes of a task's inode 3696 * @p: task 3697 * @inode: inode 3698 * 3699 * Set the security attributes for an inode based on an associated task's 3700 * security attributes, e.g. for /proc/pid inodes. 3701 */ 3702 void security_task_to_inode(struct task_struct *p, struct inode *inode) 3703 { 3704 call_void_hook(task_to_inode, p, inode); 3705 } 3706 3707 /** 3708 * security_create_user_ns() - Check if creating a new userns is allowed 3709 * @cred: prepared creds 3710 * 3711 * Check permission prior to creating a new user namespace. 3712 * 3713 * Return: Returns 0 if successful, otherwise < 0 error code. 3714 */ 3715 int security_create_user_ns(const struct cred *cred) 3716 { 3717 return call_int_hook(userns_create, cred); 3718 } 3719 3720 /** 3721 * security_ipc_permission() - Check if sysv ipc access is allowed 3722 * @ipcp: ipc permission structure 3723 * @flag: requested permissions 3724 * 3725 * Check permissions for access to IPC. 3726 * 3727 * Return: Returns 0 if permission is granted. 3728 */ 3729 int security_ipc_permission(struct kern_ipc_perm *ipcp, short flag) 3730 { 3731 return call_int_hook(ipc_permission, ipcp, flag); 3732 } 3733 3734 /** 3735 * security_ipc_getsecid() - Get the sysv ipc object's secid 3736 * @ipcp: ipc permission structure 3737 * @secid: secid pointer 3738 * 3739 * Get the secid associated with the ipc object. In case of failure, @secid 3740 * will be set to zero. 3741 */ 3742 void security_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid) 3743 { 3744 *secid = 0; 3745 call_void_hook(ipc_getsecid, ipcp, secid); 3746 } 3747 3748 /** 3749 * security_msg_msg_alloc() - Allocate a sysv ipc message LSM blob 3750 * @msg: message structure 3751 * 3752 * Allocate and attach a security structure to the msg->security field. The 3753 * security field is initialized to NULL when the structure is first created. 3754 * 3755 * Return: Return 0 if operation was successful and permission is granted. 3756 */ 3757 int security_msg_msg_alloc(struct msg_msg *msg) 3758 { 3759 int rc = lsm_msg_msg_alloc(msg); 3760 3761 if (unlikely(rc)) 3762 return rc; 3763 rc = call_int_hook(msg_msg_alloc_security, msg); 3764 if (unlikely(rc)) 3765 security_msg_msg_free(msg); 3766 return rc; 3767 } 3768 3769 /** 3770 * security_msg_msg_free() - Free a sysv ipc message LSM blob 3771 * @msg: message structure 3772 * 3773 * Deallocate the security structure for this message. 3774 */ 3775 void security_msg_msg_free(struct msg_msg *msg) 3776 { 3777 call_void_hook(msg_msg_free_security, msg); 3778 kfree(msg->security); 3779 msg->security = NULL; 3780 } 3781 3782 /** 3783 * security_msg_queue_alloc() - Allocate a sysv ipc msg queue LSM blob 3784 * @msq: sysv ipc permission structure 3785 * 3786 * Allocate and attach a security structure to @msg. The security field is 3787 * initialized to NULL when the structure is first created. 3788 * 3789 * Return: Returns 0 if operation was successful and permission is granted. 3790 */ 3791 int security_msg_queue_alloc(struct kern_ipc_perm *msq) 3792 { 3793 int rc = lsm_ipc_alloc(msq); 3794 3795 if (unlikely(rc)) 3796 return rc; 3797 rc = call_int_hook(msg_queue_alloc_security, msq); 3798 if (unlikely(rc)) 3799 security_msg_queue_free(msq); 3800 return rc; 3801 } 3802 3803 /** 3804 * security_msg_queue_free() - Free a sysv ipc msg queue LSM blob 3805 * @msq: sysv ipc permission structure 3806 * 3807 * Deallocate security field @perm->security for the message queue. 3808 */ 3809 void security_msg_queue_free(struct kern_ipc_perm *msq) 3810 { 3811 call_void_hook(msg_queue_free_security, msq); 3812 kfree(msq->security); 3813 msq->security = NULL; 3814 } 3815 3816 /** 3817 * security_msg_queue_associate() - Check if a msg queue operation is allowed 3818 * @msq: sysv ipc permission structure 3819 * @msqflg: operation flags 3820 * 3821 * Check permission when a message queue is requested through the msgget system 3822 * call. This hook is only called when returning the message queue identifier 3823 * for an existing message queue, not when a new message queue is created. 3824 * 3825 * Return: Return 0 if permission is granted. 3826 */ 3827 int security_msg_queue_associate(struct kern_ipc_perm *msq, int msqflg) 3828 { 3829 return call_int_hook(msg_queue_associate, msq, msqflg); 3830 } 3831 3832 /** 3833 * security_msg_queue_msgctl() - Check if a msg queue operation is allowed 3834 * @msq: sysv ipc permission structure 3835 * @cmd: operation 3836 * 3837 * Check permission when a message control operation specified by @cmd is to be 3838 * performed on the message queue with permissions. 3839 * 3840 * Return: Returns 0 if permission is granted. 3841 */ 3842 int security_msg_queue_msgctl(struct kern_ipc_perm *msq, int cmd) 3843 { 3844 return call_int_hook(msg_queue_msgctl, msq, cmd); 3845 } 3846 3847 /** 3848 * security_msg_queue_msgsnd() - Check if sending a sysv ipc message is allowed 3849 * @msq: sysv ipc permission structure 3850 * @msg: message 3851 * @msqflg: operation flags 3852 * 3853 * Check permission before a message, @msg, is enqueued on the message queue 3854 * with permissions specified in @msq. 3855 * 3856 * Return: Returns 0 if permission is granted. 3857 */ 3858 int security_msg_queue_msgsnd(struct kern_ipc_perm *msq, 3859 struct msg_msg *msg, int msqflg) 3860 { 3861 return call_int_hook(msg_queue_msgsnd, msq, msg, msqflg); 3862 } 3863 3864 /** 3865 * security_msg_queue_msgrcv() - Check if receiving a sysv ipc msg is allowed 3866 * @msq: sysv ipc permission structure 3867 * @msg: message 3868 * @target: target task 3869 * @type: type of message requested 3870 * @mode: operation flags 3871 * 3872 * Check permission before a message, @msg, is removed from the message queue. 3873 * The @target task structure contains a pointer to the process that will be 3874 * receiving the message (not equal to the current process when inline receives 3875 * are being performed). 3876 * 3877 * Return: Returns 0 if permission is granted. 3878 */ 3879 int security_msg_queue_msgrcv(struct kern_ipc_perm *msq, struct msg_msg *msg, 3880 struct task_struct *target, long type, int mode) 3881 { 3882 return call_int_hook(msg_queue_msgrcv, msq, msg, target, type, mode); 3883 } 3884 3885 /** 3886 * security_shm_alloc() - Allocate a sysv shm LSM blob 3887 * @shp: sysv ipc permission structure 3888 * 3889 * Allocate and attach a security structure to the @shp security field. The 3890 * security field is initialized to NULL when the structure is first created. 3891 * 3892 * Return: Returns 0 if operation was successful and permission is granted. 3893 */ 3894 int security_shm_alloc(struct kern_ipc_perm *shp) 3895 { 3896 int rc = lsm_ipc_alloc(shp); 3897 3898 if (unlikely(rc)) 3899 return rc; 3900 rc = call_int_hook(shm_alloc_security, shp); 3901 if (unlikely(rc)) 3902 security_shm_free(shp); 3903 return rc; 3904 } 3905 3906 /** 3907 * security_shm_free() - Free a sysv shm LSM blob 3908 * @shp: sysv ipc permission structure 3909 * 3910 * Deallocate the security structure @perm->security for the memory segment. 3911 */ 3912 void security_shm_free(struct kern_ipc_perm *shp) 3913 { 3914 call_void_hook(shm_free_security, shp); 3915 kfree(shp->security); 3916 shp->security = NULL; 3917 } 3918 3919 /** 3920 * security_shm_associate() - Check if a sysv shm operation is allowed 3921 * @shp: sysv ipc permission structure 3922 * @shmflg: operation flags 3923 * 3924 * Check permission when a shared memory region is requested through the shmget 3925 * system call. This hook is only called when returning the shared memory 3926 * region identifier for an existing region, not when a new shared memory 3927 * region is created. 3928 * 3929 * Return: Returns 0 if permission is granted. 3930 */ 3931 int security_shm_associate(struct kern_ipc_perm *shp, int shmflg) 3932 { 3933 return call_int_hook(shm_associate, shp, shmflg); 3934 } 3935 3936 /** 3937 * security_shm_shmctl() - Check if a sysv shm operation is allowed 3938 * @shp: sysv ipc permission structure 3939 * @cmd: operation 3940 * 3941 * Check permission when a shared memory control operation specified by @cmd is 3942 * to be performed on the shared memory region with permissions in @shp. 3943 * 3944 * Return: Return 0 if permission is granted. 3945 */ 3946 int security_shm_shmctl(struct kern_ipc_perm *shp, int cmd) 3947 { 3948 return call_int_hook(shm_shmctl, shp, cmd); 3949 } 3950 3951 /** 3952 * security_shm_shmat() - Check if a sysv shm attach operation is allowed 3953 * @shp: sysv ipc permission structure 3954 * @shmaddr: address of memory region to attach 3955 * @shmflg: operation flags 3956 * 3957 * Check permissions prior to allowing the shmat system call to attach the 3958 * shared memory segment with permissions @shp to the data segment of the 3959 * calling process. The attaching address is specified by @shmaddr. 3960 * 3961 * Return: Returns 0 if permission is granted. 3962 */ 3963 int security_shm_shmat(struct kern_ipc_perm *shp, 3964 char __user *shmaddr, int shmflg) 3965 { 3966 return call_int_hook(shm_shmat, shp, shmaddr, shmflg); 3967 } 3968 3969 /** 3970 * security_sem_alloc() - Allocate a sysv semaphore LSM blob 3971 * @sma: sysv ipc permission structure 3972 * 3973 * Allocate and attach a security structure to the @sma security field. The 3974 * security field is initialized to NULL when the structure is first created. 3975 * 3976 * Return: Returns 0 if operation was successful and permission is granted. 3977 */ 3978 int security_sem_alloc(struct kern_ipc_perm *sma) 3979 { 3980 int rc = lsm_ipc_alloc(sma); 3981 3982 if (unlikely(rc)) 3983 return rc; 3984 rc = call_int_hook(sem_alloc_security, sma); 3985 if (unlikely(rc)) 3986 security_sem_free(sma); 3987 return rc; 3988 } 3989 3990 /** 3991 * security_sem_free() - Free a sysv semaphore LSM blob 3992 * @sma: sysv ipc permission structure 3993 * 3994 * Deallocate security structure @sma->security for the semaphore. 3995 */ 3996 void security_sem_free(struct kern_ipc_perm *sma) 3997 { 3998 call_void_hook(sem_free_security, sma); 3999 kfree(sma->security); 4000 sma->security = NULL; 4001 } 4002 4003 /** 4004 * security_sem_associate() - Check if a sysv semaphore operation is allowed 4005 * @sma: sysv ipc permission structure 4006 * @semflg: operation flags 4007 * 4008 * Check permission when a semaphore is requested through the semget system 4009 * call. This hook is only called when returning the semaphore identifier for 4010 * an existing semaphore, not when a new one must be created. 4011 * 4012 * Return: Returns 0 if permission is granted. 4013 */ 4014 int security_sem_associate(struct kern_ipc_perm *sma, int semflg) 4015 { 4016 return call_int_hook(sem_associate, sma, semflg); 4017 } 4018 4019 /** 4020 * security_sem_semctl() - Check if a sysv semaphore operation is allowed 4021 * @sma: sysv ipc permission structure 4022 * @cmd: operation 4023 * 4024 * Check permission when a semaphore operation specified by @cmd is to be 4025 * performed on the semaphore. 4026 * 4027 * Return: Returns 0 if permission is granted. 4028 */ 4029 int security_sem_semctl(struct kern_ipc_perm *sma, int cmd) 4030 { 4031 return call_int_hook(sem_semctl, sma, cmd); 4032 } 4033 4034 /** 4035 * security_sem_semop() - Check if a sysv semaphore operation is allowed 4036 * @sma: sysv ipc permission structure 4037 * @sops: operations to perform 4038 * @nsops: number of operations 4039 * @alter: flag indicating changes will be made 4040 * 4041 * Check permissions before performing operations on members of the semaphore 4042 * set. If the @alter flag is nonzero, the semaphore set may be modified. 4043 * 4044 * Return: Returns 0 if permission is granted. 4045 */ 4046 int security_sem_semop(struct kern_ipc_perm *sma, struct sembuf *sops, 4047 unsigned nsops, int alter) 4048 { 4049 return call_int_hook(sem_semop, sma, sops, nsops, alter); 4050 } 4051 4052 /** 4053 * security_d_instantiate() - Populate an inode's LSM state based on a dentry 4054 * @dentry: dentry 4055 * @inode: inode 4056 * 4057 * Fill in @inode security information for a @dentry if allowed. 4058 */ 4059 void security_d_instantiate(struct dentry *dentry, struct inode *inode) 4060 { 4061 if (unlikely(inode && IS_PRIVATE(inode))) 4062 return; 4063 call_void_hook(d_instantiate, dentry, inode); 4064 } 4065 EXPORT_SYMBOL(security_d_instantiate); 4066 4067 /* 4068 * Please keep this in sync with it's counterpart in security/lsm_syscalls.c 4069 */ 4070 4071 /** 4072 * security_getselfattr - Read an LSM attribute of the current process. 4073 * @attr: which attribute to return 4074 * @uctx: the user-space destination for the information, or NULL 4075 * @size: pointer to the size of space available to receive the data 4076 * @flags: special handling options. LSM_FLAG_SINGLE indicates that only 4077 * attributes associated with the LSM identified in the passed @ctx be 4078 * reported. 4079 * 4080 * A NULL value for @uctx can be used to get both the number of attributes 4081 * and the size of the data. 4082 * 4083 * Returns the number of attributes found on success, negative value 4084 * on error. @size is reset to the total size of the data. 4085 * If @size is insufficient to contain the data -E2BIG is returned. 4086 */ 4087 int security_getselfattr(unsigned int attr, struct lsm_ctx __user *uctx, 4088 u32 __user *size, u32 flags) 4089 { 4090 struct lsm_static_call *scall; 4091 struct lsm_ctx lctx = { .id = LSM_ID_UNDEF, }; 4092 u8 __user *base = (u8 __user *)uctx; 4093 u32 entrysize; 4094 u32 total = 0; 4095 u32 left; 4096 bool toobig = false; 4097 bool single = false; 4098 int count = 0; 4099 int rc; 4100 4101 if (attr == LSM_ATTR_UNDEF) 4102 return -EINVAL; 4103 if (size == NULL) 4104 return -EINVAL; 4105 if (get_user(left, size)) 4106 return -EFAULT; 4107 4108 if (flags) { 4109 /* 4110 * Only flag supported is LSM_FLAG_SINGLE 4111 */ 4112 if (flags != LSM_FLAG_SINGLE || !uctx) 4113 return -EINVAL; 4114 if (copy_from_user(&lctx, uctx, sizeof(lctx))) 4115 return -EFAULT; 4116 /* 4117 * If the LSM ID isn't specified it is an error. 4118 */ 4119 if (lctx.id == LSM_ID_UNDEF) 4120 return -EINVAL; 4121 single = true; 4122 } 4123 4124 /* 4125 * In the usual case gather all the data from the LSMs. 4126 * In the single case only get the data from the LSM specified. 4127 */ 4128 lsm_for_each_hook(scall, getselfattr) { 4129 if (single && lctx.id != scall->hl->lsmid->id) 4130 continue; 4131 entrysize = left; 4132 if (base) 4133 uctx = (struct lsm_ctx __user *)(base + total); 4134 rc = scall->hl->hook.getselfattr(attr, uctx, &entrysize, flags); 4135 if (rc == -EOPNOTSUPP) { 4136 rc = 0; 4137 continue; 4138 } 4139 if (rc == -E2BIG) { 4140 rc = 0; 4141 left = 0; 4142 toobig = true; 4143 } else if (rc < 0) 4144 return rc; 4145 else 4146 left -= entrysize; 4147 4148 total += entrysize; 4149 count += rc; 4150 if (single) 4151 break; 4152 } 4153 if (put_user(total, size)) 4154 return -EFAULT; 4155 if (toobig) 4156 return -E2BIG; 4157 if (count == 0) 4158 return LSM_RET_DEFAULT(getselfattr); 4159 return count; 4160 } 4161 4162 /* 4163 * Please keep this in sync with it's counterpart in security/lsm_syscalls.c 4164 */ 4165 4166 /** 4167 * security_setselfattr - Set an LSM attribute on the current process. 4168 * @attr: which attribute to set 4169 * @uctx: the user-space source for the information 4170 * @size: the size of the data 4171 * @flags: reserved for future use, must be 0 4172 * 4173 * Set an LSM attribute for the current process. The LSM, attribute 4174 * and new value are included in @uctx. 4175 * 4176 * Returns 0 on success, -EINVAL if the input is inconsistent, -EFAULT 4177 * if the user buffer is inaccessible, E2BIG if size is too big, or an 4178 * LSM specific failure. 4179 */ 4180 int security_setselfattr(unsigned int attr, struct lsm_ctx __user *uctx, 4181 u32 size, u32 flags) 4182 { 4183 struct lsm_static_call *scall; 4184 struct lsm_ctx *lctx; 4185 int rc = LSM_RET_DEFAULT(setselfattr); 4186 u64 required_len; 4187 4188 if (flags) 4189 return -EINVAL; 4190 if (size < sizeof(*lctx)) 4191 return -EINVAL; 4192 if (size > PAGE_SIZE) 4193 return -E2BIG; 4194 4195 lctx = memdup_user(uctx, size); 4196 if (IS_ERR(lctx)) 4197 return PTR_ERR(lctx); 4198 4199 if (size < lctx->len || 4200 check_add_overflow(sizeof(*lctx), lctx->ctx_len, &required_len) || 4201 lctx->len < required_len) { 4202 rc = -EINVAL; 4203 goto free_out; 4204 } 4205 4206 lsm_for_each_hook(scall, setselfattr) 4207 if ((scall->hl->lsmid->id) == lctx->id) { 4208 rc = scall->hl->hook.setselfattr(attr, lctx, size, flags); 4209 break; 4210 } 4211 4212 free_out: 4213 kfree(lctx); 4214 return rc; 4215 } 4216 4217 /** 4218 * security_getprocattr() - Read an attribute for a task 4219 * @p: the task 4220 * @lsmid: LSM identification 4221 * @name: attribute name 4222 * @value: attribute value 4223 * 4224 * Read attribute @name for task @p and store it into @value if allowed. 4225 * 4226 * Return: Returns the length of @value on success, a negative value otherwise. 4227 */ 4228 int security_getprocattr(struct task_struct *p, int lsmid, const char *name, 4229 char **value) 4230 { 4231 struct lsm_static_call *scall; 4232 4233 lsm_for_each_hook(scall, getprocattr) { 4234 if (lsmid != 0 && lsmid != scall->hl->lsmid->id) 4235 continue; 4236 return scall->hl->hook.getprocattr(p, name, value); 4237 } 4238 return LSM_RET_DEFAULT(getprocattr); 4239 } 4240 4241 /** 4242 * security_setprocattr() - Set an attribute for a task 4243 * @lsmid: LSM identification 4244 * @name: attribute name 4245 * @value: attribute value 4246 * @size: attribute value size 4247 * 4248 * Write (set) the current task's attribute @name to @value, size @size if 4249 * allowed. 4250 * 4251 * Return: Returns bytes written on success, a negative value otherwise. 4252 */ 4253 int security_setprocattr(int lsmid, const char *name, void *value, size_t size) 4254 { 4255 struct lsm_static_call *scall; 4256 4257 lsm_for_each_hook(scall, setprocattr) { 4258 if (lsmid != 0 && lsmid != scall->hl->lsmid->id) 4259 continue; 4260 return scall->hl->hook.setprocattr(name, value, size); 4261 } 4262 return LSM_RET_DEFAULT(setprocattr); 4263 } 4264 4265 /** 4266 * security_netlink_send() - Save info and check if netlink sending is allowed 4267 * @sk: sending socket 4268 * @skb: netlink message 4269 * 4270 * Save security information for a netlink message so that permission checking 4271 * can be performed when the message is processed. The security information 4272 * can be saved using the eff_cap field of the netlink_skb_parms structure. 4273 * Also may be used to provide fine grained control over message transmission. 4274 * 4275 * Return: Returns 0 if the information was successfully saved and message is 4276 * allowed to be transmitted. 4277 */ 4278 int security_netlink_send(struct sock *sk, struct sk_buff *skb) 4279 { 4280 return call_int_hook(netlink_send, sk, skb); 4281 } 4282 4283 /** 4284 * security_ismaclabel() - Check if the named attribute is a MAC label 4285 * @name: full extended attribute name 4286 * 4287 * Check if the extended attribute specified by @name represents a MAC label. 4288 * 4289 * Return: Returns 1 if name is a MAC attribute otherwise returns 0. 4290 */ 4291 int security_ismaclabel(const char *name) 4292 { 4293 return call_int_hook(ismaclabel, name); 4294 } 4295 EXPORT_SYMBOL(security_ismaclabel); 4296 4297 /** 4298 * security_secid_to_secctx() - Convert a secid to a secctx 4299 * @secid: secid 4300 * @secdata: secctx 4301 * @seclen: secctx length 4302 * 4303 * Convert secid to security context. If @secdata is NULL the length of the 4304 * result will be returned in @seclen, but no @secdata will be returned. This 4305 * does mean that the length could change between calls to check the length and 4306 * the next call which actually allocates and returns the @secdata. 4307 * 4308 * Return: Return 0 on success, error on failure. 4309 */ 4310 int security_secid_to_secctx(u32 secid, char **secdata, u32 *seclen) 4311 { 4312 return call_int_hook(secid_to_secctx, secid, secdata, seclen); 4313 } 4314 EXPORT_SYMBOL(security_secid_to_secctx); 4315 4316 /** 4317 * security_secctx_to_secid() - Convert a secctx to a secid 4318 * @secdata: secctx 4319 * @seclen: length of secctx 4320 * @secid: secid 4321 * 4322 * Convert security context to secid. 4323 * 4324 * Return: Returns 0 on success, error on failure. 4325 */ 4326 int security_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid) 4327 { 4328 *secid = 0; 4329 return call_int_hook(secctx_to_secid, secdata, seclen, secid); 4330 } 4331 EXPORT_SYMBOL(security_secctx_to_secid); 4332 4333 /** 4334 * security_release_secctx() - Free a secctx buffer 4335 * @secdata: secctx 4336 * @seclen: length of secctx 4337 * 4338 * Release the security context. 4339 */ 4340 void security_release_secctx(char *secdata, u32 seclen) 4341 { 4342 call_void_hook(release_secctx, secdata, seclen); 4343 } 4344 EXPORT_SYMBOL(security_release_secctx); 4345 4346 /** 4347 * security_inode_invalidate_secctx() - Invalidate an inode's security label 4348 * @inode: inode 4349 * 4350 * Notify the security module that it must revalidate the security context of 4351 * an inode. 4352 */ 4353 void security_inode_invalidate_secctx(struct inode *inode) 4354 { 4355 call_void_hook(inode_invalidate_secctx, inode); 4356 } 4357 EXPORT_SYMBOL(security_inode_invalidate_secctx); 4358 4359 /** 4360 * security_inode_notifysecctx() - Notify the LSM of an inode's security label 4361 * @inode: inode 4362 * @ctx: secctx 4363 * @ctxlen: length of secctx 4364 * 4365 * Notify the security module of what the security context of an inode should 4366 * be. Initializes the incore security context managed by the security module 4367 * for this inode. Example usage: NFS client invokes this hook to initialize 4368 * the security context in its incore inode to the value provided by the server 4369 * for the file when the server returned the file's attributes to the client. 4370 * Must be called with inode->i_mutex locked. 4371 * 4372 * Return: Returns 0 on success, error on failure. 4373 */ 4374 int security_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen) 4375 { 4376 return call_int_hook(inode_notifysecctx, inode, ctx, ctxlen); 4377 } 4378 EXPORT_SYMBOL(security_inode_notifysecctx); 4379 4380 /** 4381 * security_inode_setsecctx() - Change the security label of an inode 4382 * @dentry: inode 4383 * @ctx: secctx 4384 * @ctxlen: length of secctx 4385 * 4386 * Change the security context of an inode. Updates the incore security 4387 * context managed by the security module and invokes the fs code as needed 4388 * (via __vfs_setxattr_noperm) to update any backing xattrs that represent the 4389 * context. Example usage: NFS server invokes this hook to change the security 4390 * context in its incore inode and on the backing filesystem to a value 4391 * provided by the client on a SETATTR operation. Must be called with 4392 * inode->i_mutex locked. 4393 * 4394 * Return: Returns 0 on success, error on failure. 4395 */ 4396 int security_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen) 4397 { 4398 return call_int_hook(inode_setsecctx, dentry, ctx, ctxlen); 4399 } 4400 EXPORT_SYMBOL(security_inode_setsecctx); 4401 4402 /** 4403 * security_inode_getsecctx() - Get the security label of an inode 4404 * @inode: inode 4405 * @ctx: secctx 4406 * @ctxlen: length of secctx 4407 * 4408 * On success, returns 0 and fills out @ctx and @ctxlen with the security 4409 * context for the given @inode. 4410 * 4411 * Return: Returns 0 on success, error on failure. 4412 */ 4413 int security_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen) 4414 { 4415 return call_int_hook(inode_getsecctx, inode, ctx, ctxlen); 4416 } 4417 EXPORT_SYMBOL(security_inode_getsecctx); 4418 4419 #ifdef CONFIG_WATCH_QUEUE 4420 /** 4421 * security_post_notification() - Check if a watch notification can be posted 4422 * @w_cred: credentials of the task that set the watch 4423 * @cred: credentials of the task which triggered the watch 4424 * @n: the notification 4425 * 4426 * Check to see if a watch notification can be posted to a particular queue. 4427 * 4428 * Return: Returns 0 if permission is granted. 4429 */ 4430 int security_post_notification(const struct cred *w_cred, 4431 const struct cred *cred, 4432 struct watch_notification *n) 4433 { 4434 return call_int_hook(post_notification, w_cred, cred, n); 4435 } 4436 #endif /* CONFIG_WATCH_QUEUE */ 4437 4438 #ifdef CONFIG_KEY_NOTIFICATIONS 4439 /** 4440 * security_watch_key() - Check if a task is allowed to watch for key events 4441 * @key: the key to watch 4442 * 4443 * Check to see if a process is allowed to watch for event notifications from 4444 * a key or keyring. 4445 * 4446 * Return: Returns 0 if permission is granted. 4447 */ 4448 int security_watch_key(struct key *key) 4449 { 4450 return call_int_hook(watch_key, key); 4451 } 4452 #endif /* CONFIG_KEY_NOTIFICATIONS */ 4453 4454 #ifdef CONFIG_SECURITY_NETWORK 4455 /** 4456 * security_unix_stream_connect() - Check if a AF_UNIX stream is allowed 4457 * @sock: originating sock 4458 * @other: peer sock 4459 * @newsk: new sock 4460 * 4461 * Check permissions before establishing a Unix domain stream connection 4462 * between @sock and @other. 4463 * 4464 * The @unix_stream_connect and @unix_may_send hooks were necessary because 4465 * Linux provides an alternative to the conventional file name space for Unix 4466 * domain sockets. Whereas binding and connecting to sockets in the file name 4467 * space is mediated by the typical file permissions (and caught by the mknod 4468 * and permission hooks in inode_security_ops), binding and connecting to 4469 * sockets in the abstract name space is completely unmediated. Sufficient 4470 * control of Unix domain sockets in the abstract name space isn't possible 4471 * using only the socket layer hooks, since we need to know the actual target 4472 * socket, which is not looked up until we are inside the af_unix code. 4473 * 4474 * Return: Returns 0 if permission is granted. 4475 */ 4476 int security_unix_stream_connect(struct sock *sock, struct sock *other, 4477 struct sock *newsk) 4478 { 4479 return call_int_hook(unix_stream_connect, sock, other, newsk); 4480 } 4481 EXPORT_SYMBOL(security_unix_stream_connect); 4482 4483 /** 4484 * security_unix_may_send() - Check if AF_UNIX socket can send datagrams 4485 * @sock: originating sock 4486 * @other: peer sock 4487 * 4488 * Check permissions before connecting or sending datagrams from @sock to 4489 * @other. 4490 * 4491 * The @unix_stream_connect and @unix_may_send hooks were necessary because 4492 * Linux provides an alternative to the conventional file name space for Unix 4493 * domain sockets. Whereas binding and connecting to sockets in the file name 4494 * space is mediated by the typical file permissions (and caught by the mknod 4495 * and permission hooks in inode_security_ops), binding and connecting to 4496 * sockets in the abstract name space is completely unmediated. Sufficient 4497 * control of Unix domain sockets in the abstract name space isn't possible 4498 * using only the socket layer hooks, since we need to know the actual target 4499 * socket, which is not looked up until we are inside the af_unix code. 4500 * 4501 * Return: Returns 0 if permission is granted. 4502 */ 4503 int security_unix_may_send(struct socket *sock, struct socket *other) 4504 { 4505 return call_int_hook(unix_may_send, sock, other); 4506 } 4507 EXPORT_SYMBOL(security_unix_may_send); 4508 4509 /** 4510 * security_socket_create() - Check if creating a new socket is allowed 4511 * @family: protocol family 4512 * @type: communications type 4513 * @protocol: requested protocol 4514 * @kern: set to 1 if a kernel socket is requested 4515 * 4516 * Check permissions prior to creating a new socket. 4517 * 4518 * Return: Returns 0 if permission is granted. 4519 */ 4520 int security_socket_create(int family, int type, int protocol, int kern) 4521 { 4522 return call_int_hook(socket_create, family, type, protocol, kern); 4523 } 4524 4525 /** 4526 * security_socket_post_create() - Initialize a newly created socket 4527 * @sock: socket 4528 * @family: protocol family 4529 * @type: communications type 4530 * @protocol: requested protocol 4531 * @kern: set to 1 if a kernel socket is requested 4532 * 4533 * This hook allows a module to update or allocate a per-socket security 4534 * structure. Note that the security field was not added directly to the socket 4535 * structure, but rather, the socket security information is stored in the 4536 * associated inode. Typically, the inode alloc_security hook will allocate 4537 * and attach security information to SOCK_INODE(sock)->i_security. This hook 4538 * may be used to update the SOCK_INODE(sock)->i_security field with additional 4539 * information that wasn't available when the inode was allocated. 4540 * 4541 * Return: Returns 0 if permission is granted. 4542 */ 4543 int security_socket_post_create(struct socket *sock, int family, 4544 int type, int protocol, int kern) 4545 { 4546 return call_int_hook(socket_post_create, sock, family, type, 4547 protocol, kern); 4548 } 4549 4550 /** 4551 * security_socket_socketpair() - Check if creating a socketpair is allowed 4552 * @socka: first socket 4553 * @sockb: second socket 4554 * 4555 * Check permissions before creating a fresh pair of sockets. 4556 * 4557 * Return: Returns 0 if permission is granted and the connection was 4558 * established. 4559 */ 4560 int security_socket_socketpair(struct socket *socka, struct socket *sockb) 4561 { 4562 return call_int_hook(socket_socketpair, socka, sockb); 4563 } 4564 EXPORT_SYMBOL(security_socket_socketpair); 4565 4566 /** 4567 * security_socket_bind() - Check if a socket bind operation is allowed 4568 * @sock: socket 4569 * @address: requested bind address 4570 * @addrlen: length of address 4571 * 4572 * Check permission before socket protocol layer bind operation is performed 4573 * and the socket @sock is bound to the address specified in the @address 4574 * parameter. 4575 * 4576 * Return: Returns 0 if permission is granted. 4577 */ 4578 int security_socket_bind(struct socket *sock, 4579 struct sockaddr *address, int addrlen) 4580 { 4581 return call_int_hook(socket_bind, sock, address, addrlen); 4582 } 4583 4584 /** 4585 * security_socket_connect() - Check if a socket connect operation is allowed 4586 * @sock: socket 4587 * @address: address of remote connection point 4588 * @addrlen: length of address 4589 * 4590 * Check permission before socket protocol layer connect operation attempts to 4591 * connect socket @sock to a remote address, @address. 4592 * 4593 * Return: Returns 0 if permission is granted. 4594 */ 4595 int security_socket_connect(struct socket *sock, 4596 struct sockaddr *address, int addrlen) 4597 { 4598 return call_int_hook(socket_connect, sock, address, addrlen); 4599 } 4600 4601 /** 4602 * security_socket_listen() - Check if a socket is allowed to listen 4603 * @sock: socket 4604 * @backlog: connection queue size 4605 * 4606 * Check permission before socket protocol layer listen operation. 4607 * 4608 * Return: Returns 0 if permission is granted. 4609 */ 4610 int security_socket_listen(struct socket *sock, int backlog) 4611 { 4612 return call_int_hook(socket_listen, sock, backlog); 4613 } 4614 4615 /** 4616 * security_socket_accept() - Check if a socket is allowed to accept connections 4617 * @sock: listening socket 4618 * @newsock: newly creation connection socket 4619 * 4620 * Check permission before accepting a new connection. Note that the new 4621 * socket, @newsock, has been created and some information copied to it, but 4622 * the accept operation has not actually been performed. 4623 * 4624 * Return: Returns 0 if permission is granted. 4625 */ 4626 int security_socket_accept(struct socket *sock, struct socket *newsock) 4627 { 4628 return call_int_hook(socket_accept, sock, newsock); 4629 } 4630 4631 /** 4632 * security_socket_sendmsg() - Check if sending a message is allowed 4633 * @sock: sending socket 4634 * @msg: message to send 4635 * @size: size of message 4636 * 4637 * Check permission before transmitting a message to another socket. 4638 * 4639 * Return: Returns 0 if permission is granted. 4640 */ 4641 int security_socket_sendmsg(struct socket *sock, struct msghdr *msg, int size) 4642 { 4643 return call_int_hook(socket_sendmsg, sock, msg, size); 4644 } 4645 4646 /** 4647 * security_socket_recvmsg() - Check if receiving a message is allowed 4648 * @sock: receiving socket 4649 * @msg: message to receive 4650 * @size: size of message 4651 * @flags: operational flags 4652 * 4653 * Check permission before receiving a message from a socket. 4654 * 4655 * Return: Returns 0 if permission is granted. 4656 */ 4657 int security_socket_recvmsg(struct socket *sock, struct msghdr *msg, 4658 int size, int flags) 4659 { 4660 return call_int_hook(socket_recvmsg, sock, msg, size, flags); 4661 } 4662 4663 /** 4664 * security_socket_getsockname() - Check if reading the socket addr is allowed 4665 * @sock: socket 4666 * 4667 * Check permission before reading the local address (name) of the socket 4668 * object. 4669 * 4670 * Return: Returns 0 if permission is granted. 4671 */ 4672 int security_socket_getsockname(struct socket *sock) 4673 { 4674 return call_int_hook(socket_getsockname, sock); 4675 } 4676 4677 /** 4678 * security_socket_getpeername() - Check if reading the peer's addr is allowed 4679 * @sock: socket 4680 * 4681 * Check permission before the remote address (name) of a socket object. 4682 * 4683 * Return: Returns 0 if permission is granted. 4684 */ 4685 int security_socket_getpeername(struct socket *sock) 4686 { 4687 return call_int_hook(socket_getpeername, sock); 4688 } 4689 4690 /** 4691 * security_socket_getsockopt() - Check if reading a socket option is allowed 4692 * @sock: socket 4693 * @level: option's protocol level 4694 * @optname: option name 4695 * 4696 * Check permissions before retrieving the options associated with socket 4697 * @sock. 4698 * 4699 * Return: Returns 0 if permission is granted. 4700 */ 4701 int security_socket_getsockopt(struct socket *sock, int level, int optname) 4702 { 4703 return call_int_hook(socket_getsockopt, sock, level, optname); 4704 } 4705 4706 /** 4707 * security_socket_setsockopt() - Check if setting a socket option is allowed 4708 * @sock: socket 4709 * @level: option's protocol level 4710 * @optname: option name 4711 * 4712 * Check permissions before setting the options associated with socket @sock. 4713 * 4714 * Return: Returns 0 if permission is granted. 4715 */ 4716 int security_socket_setsockopt(struct socket *sock, int level, int optname) 4717 { 4718 return call_int_hook(socket_setsockopt, sock, level, optname); 4719 } 4720 4721 /** 4722 * security_socket_shutdown() - Checks if shutting down the socket is allowed 4723 * @sock: socket 4724 * @how: flag indicating how sends and receives are handled 4725 * 4726 * Checks permission before all or part of a connection on the socket @sock is 4727 * shut down. 4728 * 4729 * Return: Returns 0 if permission is granted. 4730 */ 4731 int security_socket_shutdown(struct socket *sock, int how) 4732 { 4733 return call_int_hook(socket_shutdown, sock, how); 4734 } 4735 4736 /** 4737 * security_sock_rcv_skb() - Check if an incoming network packet is allowed 4738 * @sk: destination sock 4739 * @skb: incoming packet 4740 * 4741 * Check permissions on incoming network packets. This hook is distinct from 4742 * Netfilter's IP input hooks since it is the first time that the incoming 4743 * sk_buff @skb has been associated with a particular socket, @sk. Must not 4744 * sleep inside this hook because some callers hold spinlocks. 4745 * 4746 * Return: Returns 0 if permission is granted. 4747 */ 4748 int security_sock_rcv_skb(struct sock *sk, struct sk_buff *skb) 4749 { 4750 return call_int_hook(socket_sock_rcv_skb, sk, skb); 4751 } 4752 EXPORT_SYMBOL(security_sock_rcv_skb); 4753 4754 /** 4755 * security_socket_getpeersec_stream() - Get the remote peer label 4756 * @sock: socket 4757 * @optval: destination buffer 4758 * @optlen: size of peer label copied into the buffer 4759 * @len: maximum size of the destination buffer 4760 * 4761 * This hook allows the security module to provide peer socket security state 4762 * for unix or connected tcp sockets to userspace via getsockopt SO_GETPEERSEC. 4763 * For tcp sockets this can be meaningful if the socket is associated with an 4764 * ipsec SA. 4765 * 4766 * Return: Returns 0 if all is well, otherwise, typical getsockopt return 4767 * values. 4768 */ 4769 int security_socket_getpeersec_stream(struct socket *sock, sockptr_t optval, 4770 sockptr_t optlen, unsigned int len) 4771 { 4772 return call_int_hook(socket_getpeersec_stream, sock, optval, optlen, 4773 len); 4774 } 4775 4776 /** 4777 * security_socket_getpeersec_dgram() - Get the remote peer label 4778 * @sock: socket 4779 * @skb: datagram packet 4780 * @secid: remote peer label secid 4781 * 4782 * This hook allows the security module to provide peer socket security state 4783 * for udp sockets on a per-packet basis to userspace via getsockopt 4784 * SO_GETPEERSEC. The application must first have indicated the IP_PASSSEC 4785 * option via getsockopt. It can then retrieve the security state returned by 4786 * this hook for a packet via the SCM_SECURITY ancillary message type. 4787 * 4788 * Return: Returns 0 on success, error on failure. 4789 */ 4790 int security_socket_getpeersec_dgram(struct socket *sock, 4791 struct sk_buff *skb, u32 *secid) 4792 { 4793 return call_int_hook(socket_getpeersec_dgram, sock, skb, secid); 4794 } 4795 EXPORT_SYMBOL(security_socket_getpeersec_dgram); 4796 4797 /** 4798 * lsm_sock_alloc - allocate a composite sock blob 4799 * @sock: the sock that needs a blob 4800 * @gfp: allocation mode 4801 * 4802 * Allocate the sock blob for all the modules 4803 * 4804 * Returns 0, or -ENOMEM if memory can't be allocated. 4805 */ 4806 static int lsm_sock_alloc(struct sock *sock, gfp_t gfp) 4807 { 4808 return lsm_blob_alloc(&sock->sk_security, blob_sizes.lbs_sock, gfp); 4809 } 4810 4811 /** 4812 * security_sk_alloc() - Allocate and initialize a sock's LSM blob 4813 * @sk: sock 4814 * @family: protocol family 4815 * @priority: gfp flags 4816 * 4817 * Allocate and attach a security structure to the sk->sk_security field, which 4818 * is used to copy security attributes between local stream sockets. 4819 * 4820 * Return: Returns 0 on success, error on failure. 4821 */ 4822 int security_sk_alloc(struct sock *sk, int family, gfp_t priority) 4823 { 4824 int rc = lsm_sock_alloc(sk, priority); 4825 4826 if (unlikely(rc)) 4827 return rc; 4828 rc = call_int_hook(sk_alloc_security, sk, family, priority); 4829 if (unlikely(rc)) 4830 security_sk_free(sk); 4831 return rc; 4832 } 4833 4834 /** 4835 * security_sk_free() - Free the sock's LSM blob 4836 * @sk: sock 4837 * 4838 * Deallocate security structure. 4839 */ 4840 void security_sk_free(struct sock *sk) 4841 { 4842 call_void_hook(sk_free_security, sk); 4843 kfree(sk->sk_security); 4844 sk->sk_security = NULL; 4845 } 4846 4847 /** 4848 * security_sk_clone() - Clone a sock's LSM state 4849 * @sk: original sock 4850 * @newsk: target sock 4851 * 4852 * Clone/copy security structure. 4853 */ 4854 void security_sk_clone(const struct sock *sk, struct sock *newsk) 4855 { 4856 call_void_hook(sk_clone_security, sk, newsk); 4857 } 4858 EXPORT_SYMBOL(security_sk_clone); 4859 4860 /** 4861 * security_sk_classify_flow() - Set a flow's secid based on socket 4862 * @sk: original socket 4863 * @flic: target flow 4864 * 4865 * Set the target flow's secid to socket's secid. 4866 */ 4867 void security_sk_classify_flow(const struct sock *sk, struct flowi_common *flic) 4868 { 4869 call_void_hook(sk_getsecid, sk, &flic->flowic_secid); 4870 } 4871 EXPORT_SYMBOL(security_sk_classify_flow); 4872 4873 /** 4874 * security_req_classify_flow() - Set a flow's secid based on request_sock 4875 * @req: request_sock 4876 * @flic: target flow 4877 * 4878 * Sets @flic's secid to @req's secid. 4879 */ 4880 void security_req_classify_flow(const struct request_sock *req, 4881 struct flowi_common *flic) 4882 { 4883 call_void_hook(req_classify_flow, req, flic); 4884 } 4885 EXPORT_SYMBOL(security_req_classify_flow); 4886 4887 /** 4888 * security_sock_graft() - Reconcile LSM state when grafting a sock on a socket 4889 * @sk: sock being grafted 4890 * @parent: target parent socket 4891 * 4892 * Sets @parent's inode secid to @sk's secid and update @sk with any necessary 4893 * LSM state from @parent. 4894 */ 4895 void security_sock_graft(struct sock *sk, struct socket *parent) 4896 { 4897 call_void_hook(sock_graft, sk, parent); 4898 } 4899 EXPORT_SYMBOL(security_sock_graft); 4900 4901 /** 4902 * security_inet_conn_request() - Set request_sock state using incoming connect 4903 * @sk: parent listening sock 4904 * @skb: incoming connection 4905 * @req: new request_sock 4906 * 4907 * Initialize the @req LSM state based on @sk and the incoming connect in @skb. 4908 * 4909 * Return: Returns 0 if permission is granted. 4910 */ 4911 int security_inet_conn_request(const struct sock *sk, 4912 struct sk_buff *skb, struct request_sock *req) 4913 { 4914 return call_int_hook(inet_conn_request, sk, skb, req); 4915 } 4916 EXPORT_SYMBOL(security_inet_conn_request); 4917 4918 /** 4919 * security_inet_csk_clone() - Set new sock LSM state based on request_sock 4920 * @newsk: new sock 4921 * @req: connection request_sock 4922 * 4923 * Set that LSM state of @sock using the LSM state from @req. 4924 */ 4925 void security_inet_csk_clone(struct sock *newsk, 4926 const struct request_sock *req) 4927 { 4928 call_void_hook(inet_csk_clone, newsk, req); 4929 } 4930 4931 /** 4932 * security_inet_conn_established() - Update sock's LSM state with connection 4933 * @sk: sock 4934 * @skb: connection packet 4935 * 4936 * Update @sock's LSM state to represent a new connection from @skb. 4937 */ 4938 void security_inet_conn_established(struct sock *sk, 4939 struct sk_buff *skb) 4940 { 4941 call_void_hook(inet_conn_established, sk, skb); 4942 } 4943 EXPORT_SYMBOL(security_inet_conn_established); 4944 4945 /** 4946 * security_secmark_relabel_packet() - Check if setting a secmark is allowed 4947 * @secid: new secmark value 4948 * 4949 * Check if the process should be allowed to relabel packets to @secid. 4950 * 4951 * Return: Returns 0 if permission is granted. 4952 */ 4953 int security_secmark_relabel_packet(u32 secid) 4954 { 4955 return call_int_hook(secmark_relabel_packet, secid); 4956 } 4957 EXPORT_SYMBOL(security_secmark_relabel_packet); 4958 4959 /** 4960 * security_secmark_refcount_inc() - Increment the secmark labeling rule count 4961 * 4962 * Tells the LSM to increment the number of secmark labeling rules loaded. 4963 */ 4964 void security_secmark_refcount_inc(void) 4965 { 4966 call_void_hook(secmark_refcount_inc); 4967 } 4968 EXPORT_SYMBOL(security_secmark_refcount_inc); 4969 4970 /** 4971 * security_secmark_refcount_dec() - Decrement the secmark labeling rule count 4972 * 4973 * Tells the LSM to decrement the number of secmark labeling rules loaded. 4974 */ 4975 void security_secmark_refcount_dec(void) 4976 { 4977 call_void_hook(secmark_refcount_dec); 4978 } 4979 EXPORT_SYMBOL(security_secmark_refcount_dec); 4980 4981 /** 4982 * security_tun_dev_alloc_security() - Allocate a LSM blob for a TUN device 4983 * @security: pointer to the LSM blob 4984 * 4985 * This hook allows a module to allocate a security structure for a TUN device, 4986 * returning the pointer in @security. 4987 * 4988 * Return: Returns a zero on success, negative values on failure. 4989 */ 4990 int security_tun_dev_alloc_security(void **security) 4991 { 4992 int rc; 4993 4994 rc = lsm_blob_alloc(security, blob_sizes.lbs_tun_dev, GFP_KERNEL); 4995 if (rc) 4996 return rc; 4997 4998 rc = call_int_hook(tun_dev_alloc_security, *security); 4999 if (rc) { 5000 kfree(*security); 5001 *security = NULL; 5002 } 5003 return rc; 5004 } 5005 EXPORT_SYMBOL(security_tun_dev_alloc_security); 5006 5007 /** 5008 * security_tun_dev_free_security() - Free a TUN device LSM blob 5009 * @security: LSM blob 5010 * 5011 * This hook allows a module to free the security structure for a TUN device. 5012 */ 5013 void security_tun_dev_free_security(void *security) 5014 { 5015 kfree(security); 5016 } 5017 EXPORT_SYMBOL(security_tun_dev_free_security); 5018 5019 /** 5020 * security_tun_dev_create() - Check if creating a TUN device is allowed 5021 * 5022 * Check permissions prior to creating a new TUN device. 5023 * 5024 * Return: Returns 0 if permission is granted. 5025 */ 5026 int security_tun_dev_create(void) 5027 { 5028 return call_int_hook(tun_dev_create); 5029 } 5030 EXPORT_SYMBOL(security_tun_dev_create); 5031 5032 /** 5033 * security_tun_dev_attach_queue() - Check if attaching a TUN queue is allowed 5034 * @security: TUN device LSM blob 5035 * 5036 * Check permissions prior to attaching to a TUN device queue. 5037 * 5038 * Return: Returns 0 if permission is granted. 5039 */ 5040 int security_tun_dev_attach_queue(void *security) 5041 { 5042 return call_int_hook(tun_dev_attach_queue, security); 5043 } 5044 EXPORT_SYMBOL(security_tun_dev_attach_queue); 5045 5046 /** 5047 * security_tun_dev_attach() - Update TUN device LSM state on attach 5048 * @sk: associated sock 5049 * @security: TUN device LSM blob 5050 * 5051 * This hook can be used by the module to update any security state associated 5052 * with the TUN device's sock structure. 5053 * 5054 * Return: Returns 0 if permission is granted. 5055 */ 5056 int security_tun_dev_attach(struct sock *sk, void *security) 5057 { 5058 return call_int_hook(tun_dev_attach, sk, security); 5059 } 5060 EXPORT_SYMBOL(security_tun_dev_attach); 5061 5062 /** 5063 * security_tun_dev_open() - Update TUN device LSM state on open 5064 * @security: TUN device LSM blob 5065 * 5066 * This hook can be used by the module to update any security state associated 5067 * with the TUN device's security structure. 5068 * 5069 * Return: Returns 0 if permission is granted. 5070 */ 5071 int security_tun_dev_open(void *security) 5072 { 5073 return call_int_hook(tun_dev_open, security); 5074 } 5075 EXPORT_SYMBOL(security_tun_dev_open); 5076 5077 /** 5078 * security_sctp_assoc_request() - Update the LSM on a SCTP association req 5079 * @asoc: SCTP association 5080 * @skb: packet requesting the association 5081 * 5082 * Passes the @asoc and @chunk->skb of the association INIT packet to the LSM. 5083 * 5084 * Return: Returns 0 on success, error on failure. 5085 */ 5086 int security_sctp_assoc_request(struct sctp_association *asoc, 5087 struct sk_buff *skb) 5088 { 5089 return call_int_hook(sctp_assoc_request, asoc, skb); 5090 } 5091 EXPORT_SYMBOL(security_sctp_assoc_request); 5092 5093 /** 5094 * security_sctp_bind_connect() - Validate a list of addrs for a SCTP option 5095 * @sk: socket 5096 * @optname: SCTP option to validate 5097 * @address: list of IP addresses to validate 5098 * @addrlen: length of the address list 5099 * 5100 * Validiate permissions required for each address associated with sock @sk. 5101 * Depending on @optname, the addresses will be treated as either a connect or 5102 * bind service. The @addrlen is calculated on each IPv4 and IPv6 address using 5103 * sizeof(struct sockaddr_in) or sizeof(struct sockaddr_in6). 5104 * 5105 * Return: Returns 0 on success, error on failure. 5106 */ 5107 int security_sctp_bind_connect(struct sock *sk, int optname, 5108 struct sockaddr *address, int addrlen) 5109 { 5110 return call_int_hook(sctp_bind_connect, sk, optname, address, addrlen); 5111 } 5112 EXPORT_SYMBOL(security_sctp_bind_connect); 5113 5114 /** 5115 * security_sctp_sk_clone() - Clone a SCTP sock's LSM state 5116 * @asoc: SCTP association 5117 * @sk: original sock 5118 * @newsk: target sock 5119 * 5120 * Called whenever a new socket is created by accept(2) (i.e. a TCP style 5121 * socket) or when a socket is 'peeled off' e.g userspace calls 5122 * sctp_peeloff(3). 5123 */ 5124 void security_sctp_sk_clone(struct sctp_association *asoc, struct sock *sk, 5125 struct sock *newsk) 5126 { 5127 call_void_hook(sctp_sk_clone, asoc, sk, newsk); 5128 } 5129 EXPORT_SYMBOL(security_sctp_sk_clone); 5130 5131 /** 5132 * security_sctp_assoc_established() - Update LSM state when assoc established 5133 * @asoc: SCTP association 5134 * @skb: packet establishing the association 5135 * 5136 * Passes the @asoc and @chunk->skb of the association COOKIE_ACK packet to the 5137 * security module. 5138 * 5139 * Return: Returns 0 if permission is granted. 5140 */ 5141 int security_sctp_assoc_established(struct sctp_association *asoc, 5142 struct sk_buff *skb) 5143 { 5144 return call_int_hook(sctp_assoc_established, asoc, skb); 5145 } 5146 EXPORT_SYMBOL(security_sctp_assoc_established); 5147 5148 /** 5149 * security_mptcp_add_subflow() - Inherit the LSM label from the MPTCP socket 5150 * @sk: the owning MPTCP socket 5151 * @ssk: the new subflow 5152 * 5153 * Update the labeling for the given MPTCP subflow, to match the one of the 5154 * owning MPTCP socket. This hook has to be called after the socket creation and 5155 * initialization via the security_socket_create() and 5156 * security_socket_post_create() LSM hooks. 5157 * 5158 * Return: Returns 0 on success or a negative error code on failure. 5159 */ 5160 int security_mptcp_add_subflow(struct sock *sk, struct sock *ssk) 5161 { 5162 return call_int_hook(mptcp_add_subflow, sk, ssk); 5163 } 5164 5165 #endif /* CONFIG_SECURITY_NETWORK */ 5166 5167 #ifdef CONFIG_SECURITY_INFINIBAND 5168 /** 5169 * security_ib_pkey_access() - Check if access to an IB pkey is allowed 5170 * @sec: LSM blob 5171 * @subnet_prefix: subnet prefix of the port 5172 * @pkey: IB pkey 5173 * 5174 * Check permission to access a pkey when modifying a QP. 5175 * 5176 * Return: Returns 0 if permission is granted. 5177 */ 5178 int security_ib_pkey_access(void *sec, u64 subnet_prefix, u16 pkey) 5179 { 5180 return call_int_hook(ib_pkey_access, sec, subnet_prefix, pkey); 5181 } 5182 EXPORT_SYMBOL(security_ib_pkey_access); 5183 5184 /** 5185 * security_ib_endport_manage_subnet() - Check if SMPs traffic is allowed 5186 * @sec: LSM blob 5187 * @dev_name: IB device name 5188 * @port_num: port number 5189 * 5190 * Check permissions to send and receive SMPs on a end port. 5191 * 5192 * Return: Returns 0 if permission is granted. 5193 */ 5194 int security_ib_endport_manage_subnet(void *sec, 5195 const char *dev_name, u8 port_num) 5196 { 5197 return call_int_hook(ib_endport_manage_subnet, sec, dev_name, port_num); 5198 } 5199 EXPORT_SYMBOL(security_ib_endport_manage_subnet); 5200 5201 /** 5202 * security_ib_alloc_security() - Allocate an Infiniband LSM blob 5203 * @sec: LSM blob 5204 * 5205 * Allocate a security structure for Infiniband objects. 5206 * 5207 * Return: Returns 0 on success, non-zero on failure. 5208 */ 5209 int security_ib_alloc_security(void **sec) 5210 { 5211 int rc; 5212 5213 rc = lsm_blob_alloc(sec, blob_sizes.lbs_ib, GFP_KERNEL); 5214 if (rc) 5215 return rc; 5216 5217 rc = call_int_hook(ib_alloc_security, *sec); 5218 if (rc) { 5219 kfree(*sec); 5220 *sec = NULL; 5221 } 5222 return rc; 5223 } 5224 EXPORT_SYMBOL(security_ib_alloc_security); 5225 5226 /** 5227 * security_ib_free_security() - Free an Infiniband LSM blob 5228 * @sec: LSM blob 5229 * 5230 * Deallocate an Infiniband security structure. 5231 */ 5232 void security_ib_free_security(void *sec) 5233 { 5234 kfree(sec); 5235 } 5236 EXPORT_SYMBOL(security_ib_free_security); 5237 #endif /* CONFIG_SECURITY_INFINIBAND */ 5238 5239 #ifdef CONFIG_SECURITY_NETWORK_XFRM 5240 /** 5241 * security_xfrm_policy_alloc() - Allocate a xfrm policy LSM blob 5242 * @ctxp: xfrm security context being added to the SPD 5243 * @sec_ctx: security label provided by userspace 5244 * @gfp: gfp flags 5245 * 5246 * Allocate a security structure to the xp->security field; the security field 5247 * is initialized to NULL when the xfrm_policy is allocated. 5248 * 5249 * Return: Return 0 if operation was successful. 5250 */ 5251 int security_xfrm_policy_alloc(struct xfrm_sec_ctx **ctxp, 5252 struct xfrm_user_sec_ctx *sec_ctx, 5253 gfp_t gfp) 5254 { 5255 return call_int_hook(xfrm_policy_alloc_security, ctxp, sec_ctx, gfp); 5256 } 5257 EXPORT_SYMBOL(security_xfrm_policy_alloc); 5258 5259 /** 5260 * security_xfrm_policy_clone() - Clone xfrm policy LSM state 5261 * @old_ctx: xfrm security context 5262 * @new_ctxp: target xfrm security context 5263 * 5264 * Allocate a security structure in new_ctxp that contains the information from 5265 * the old_ctx structure. 5266 * 5267 * Return: Return 0 if operation was successful. 5268 */ 5269 int security_xfrm_policy_clone(struct xfrm_sec_ctx *old_ctx, 5270 struct xfrm_sec_ctx **new_ctxp) 5271 { 5272 return call_int_hook(xfrm_policy_clone_security, old_ctx, new_ctxp); 5273 } 5274 5275 /** 5276 * security_xfrm_policy_free() - Free a xfrm security context 5277 * @ctx: xfrm security context 5278 * 5279 * Free LSM resources associated with @ctx. 5280 */ 5281 void security_xfrm_policy_free(struct xfrm_sec_ctx *ctx) 5282 { 5283 call_void_hook(xfrm_policy_free_security, ctx); 5284 } 5285 EXPORT_SYMBOL(security_xfrm_policy_free); 5286 5287 /** 5288 * security_xfrm_policy_delete() - Check if deleting a xfrm policy is allowed 5289 * @ctx: xfrm security context 5290 * 5291 * Authorize deletion of a SPD entry. 5292 * 5293 * Return: Returns 0 if permission is granted. 5294 */ 5295 int security_xfrm_policy_delete(struct xfrm_sec_ctx *ctx) 5296 { 5297 return call_int_hook(xfrm_policy_delete_security, ctx); 5298 } 5299 5300 /** 5301 * security_xfrm_state_alloc() - Allocate a xfrm state LSM blob 5302 * @x: xfrm state being added to the SAD 5303 * @sec_ctx: security label provided by userspace 5304 * 5305 * Allocate a security structure to the @x->security field; the security field 5306 * is initialized to NULL when the xfrm_state is allocated. Set the context to 5307 * correspond to @sec_ctx. 5308 * 5309 * Return: Return 0 if operation was successful. 5310 */ 5311 int security_xfrm_state_alloc(struct xfrm_state *x, 5312 struct xfrm_user_sec_ctx *sec_ctx) 5313 { 5314 return call_int_hook(xfrm_state_alloc, x, sec_ctx); 5315 } 5316 EXPORT_SYMBOL(security_xfrm_state_alloc); 5317 5318 /** 5319 * security_xfrm_state_alloc_acquire() - Allocate a xfrm state LSM blob 5320 * @x: xfrm state being added to the SAD 5321 * @polsec: associated policy's security context 5322 * @secid: secid from the flow 5323 * 5324 * Allocate a security structure to the x->security field; the security field 5325 * is initialized to NULL when the xfrm_state is allocated. Set the context to 5326 * correspond to secid. 5327 * 5328 * Return: Returns 0 if operation was successful. 5329 */ 5330 int security_xfrm_state_alloc_acquire(struct xfrm_state *x, 5331 struct xfrm_sec_ctx *polsec, u32 secid) 5332 { 5333 return call_int_hook(xfrm_state_alloc_acquire, x, polsec, secid); 5334 } 5335 5336 /** 5337 * security_xfrm_state_delete() - Check if deleting a xfrm state is allowed 5338 * @x: xfrm state 5339 * 5340 * Authorize deletion of x->security. 5341 * 5342 * Return: Returns 0 if permission is granted. 5343 */ 5344 int security_xfrm_state_delete(struct xfrm_state *x) 5345 { 5346 return call_int_hook(xfrm_state_delete_security, x); 5347 } 5348 EXPORT_SYMBOL(security_xfrm_state_delete); 5349 5350 /** 5351 * security_xfrm_state_free() - Free a xfrm state 5352 * @x: xfrm state 5353 * 5354 * Deallocate x->security. 5355 */ 5356 void security_xfrm_state_free(struct xfrm_state *x) 5357 { 5358 call_void_hook(xfrm_state_free_security, x); 5359 } 5360 5361 /** 5362 * security_xfrm_policy_lookup() - Check if using a xfrm policy is allowed 5363 * @ctx: target xfrm security context 5364 * @fl_secid: flow secid used to authorize access 5365 * 5366 * Check permission when a flow selects a xfrm_policy for processing XFRMs on a 5367 * packet. The hook is called when selecting either a per-socket policy or a 5368 * generic xfrm policy. 5369 * 5370 * Return: Return 0 if permission is granted, -ESRCH otherwise, or -errno on 5371 * other errors. 5372 */ 5373 int security_xfrm_policy_lookup(struct xfrm_sec_ctx *ctx, u32 fl_secid) 5374 { 5375 return call_int_hook(xfrm_policy_lookup, ctx, fl_secid); 5376 } 5377 5378 /** 5379 * security_xfrm_state_pol_flow_match() - Check for a xfrm match 5380 * @x: xfrm state to match 5381 * @xp: xfrm policy to check for a match 5382 * @flic: flow to check for a match. 5383 * 5384 * Check @xp and @flic for a match with @x. 5385 * 5386 * Return: Returns 1 if there is a match. 5387 */ 5388 int security_xfrm_state_pol_flow_match(struct xfrm_state *x, 5389 struct xfrm_policy *xp, 5390 const struct flowi_common *flic) 5391 { 5392 struct lsm_static_call *scall; 5393 int rc = LSM_RET_DEFAULT(xfrm_state_pol_flow_match); 5394 5395 /* 5396 * Since this function is expected to return 0 or 1, the judgment 5397 * becomes difficult if multiple LSMs supply this call. Fortunately, 5398 * we can use the first LSM's judgment because currently only SELinux 5399 * supplies this call. 5400 * 5401 * For speed optimization, we explicitly break the loop rather than 5402 * using the macro 5403 */ 5404 lsm_for_each_hook(scall, xfrm_state_pol_flow_match) { 5405 rc = scall->hl->hook.xfrm_state_pol_flow_match(x, xp, flic); 5406 break; 5407 } 5408 return rc; 5409 } 5410 5411 /** 5412 * security_xfrm_decode_session() - Determine the xfrm secid for a packet 5413 * @skb: xfrm packet 5414 * @secid: secid 5415 * 5416 * Decode the packet in @skb and return the security label in @secid. 5417 * 5418 * Return: Return 0 if all xfrms used have the same secid. 5419 */ 5420 int security_xfrm_decode_session(struct sk_buff *skb, u32 *secid) 5421 { 5422 return call_int_hook(xfrm_decode_session, skb, secid, 1); 5423 } 5424 5425 void security_skb_classify_flow(struct sk_buff *skb, struct flowi_common *flic) 5426 { 5427 int rc = call_int_hook(xfrm_decode_session, skb, &flic->flowic_secid, 5428 0); 5429 5430 BUG_ON(rc); 5431 } 5432 EXPORT_SYMBOL(security_skb_classify_flow); 5433 #endif /* CONFIG_SECURITY_NETWORK_XFRM */ 5434 5435 #ifdef CONFIG_KEYS 5436 /** 5437 * security_key_alloc() - Allocate and initialize a kernel key LSM blob 5438 * @key: key 5439 * @cred: credentials 5440 * @flags: allocation flags 5441 * 5442 * Permit allocation of a key and assign security data. Note that key does not 5443 * have a serial number assigned at this point. 5444 * 5445 * Return: Return 0 if permission is granted, -ve error otherwise. 5446 */ 5447 int security_key_alloc(struct key *key, const struct cred *cred, 5448 unsigned long flags) 5449 { 5450 int rc = lsm_key_alloc(key); 5451 5452 if (unlikely(rc)) 5453 return rc; 5454 rc = call_int_hook(key_alloc, key, cred, flags); 5455 if (unlikely(rc)) 5456 security_key_free(key); 5457 return rc; 5458 } 5459 5460 /** 5461 * security_key_free() - Free a kernel key LSM blob 5462 * @key: key 5463 * 5464 * Notification of destruction; free security data. 5465 */ 5466 void security_key_free(struct key *key) 5467 { 5468 kfree(key->security); 5469 key->security = NULL; 5470 } 5471 5472 /** 5473 * security_key_permission() - Check if a kernel key operation is allowed 5474 * @key_ref: key reference 5475 * @cred: credentials of actor requesting access 5476 * @need_perm: requested permissions 5477 * 5478 * See whether a specific operational right is granted to a process on a key. 5479 * 5480 * Return: Return 0 if permission is granted, -ve error otherwise. 5481 */ 5482 int security_key_permission(key_ref_t key_ref, const struct cred *cred, 5483 enum key_need_perm need_perm) 5484 { 5485 return call_int_hook(key_permission, key_ref, cred, need_perm); 5486 } 5487 5488 /** 5489 * security_key_getsecurity() - Get the key's security label 5490 * @key: key 5491 * @buffer: security label buffer 5492 * 5493 * Get a textual representation of the security context attached to a key for 5494 * the purposes of honouring KEYCTL_GETSECURITY. This function allocates the 5495 * storage for the NUL-terminated string and the caller should free it. 5496 * 5497 * Return: Returns the length of @buffer (including terminating NUL) or -ve if 5498 * an error occurs. May also return 0 (and a NULL buffer pointer) if 5499 * there is no security label assigned to the key. 5500 */ 5501 int security_key_getsecurity(struct key *key, char **buffer) 5502 { 5503 *buffer = NULL; 5504 return call_int_hook(key_getsecurity, key, buffer); 5505 } 5506 5507 /** 5508 * security_key_post_create_or_update() - Notification of key create or update 5509 * @keyring: keyring to which the key is linked to 5510 * @key: created or updated key 5511 * @payload: data used to instantiate or update the key 5512 * @payload_len: length of payload 5513 * @flags: key flags 5514 * @create: flag indicating whether the key was created or updated 5515 * 5516 * Notify the caller of a key creation or update. 5517 */ 5518 void security_key_post_create_or_update(struct key *keyring, struct key *key, 5519 const void *payload, size_t payload_len, 5520 unsigned long flags, bool create) 5521 { 5522 call_void_hook(key_post_create_or_update, keyring, key, payload, 5523 payload_len, flags, create); 5524 } 5525 #endif /* CONFIG_KEYS */ 5526 5527 #ifdef CONFIG_AUDIT 5528 /** 5529 * security_audit_rule_init() - Allocate and init an LSM audit rule struct 5530 * @field: audit action 5531 * @op: rule operator 5532 * @rulestr: rule context 5533 * @lsmrule: receive buffer for audit rule struct 5534 * @gfp: GFP flag used for kmalloc 5535 * 5536 * Allocate and initialize an LSM audit rule structure. 5537 * 5538 * Return: Return 0 if @lsmrule has been successfully set, -EINVAL in case of 5539 * an invalid rule. 5540 */ 5541 int security_audit_rule_init(u32 field, u32 op, char *rulestr, void **lsmrule, 5542 gfp_t gfp) 5543 { 5544 return call_int_hook(audit_rule_init, field, op, rulestr, lsmrule, gfp); 5545 } 5546 5547 /** 5548 * security_audit_rule_known() - Check if an audit rule contains LSM fields 5549 * @krule: audit rule 5550 * 5551 * Specifies whether given @krule contains any fields related to the current 5552 * LSM. 5553 * 5554 * Return: Returns 1 in case of relation found, 0 otherwise. 5555 */ 5556 int security_audit_rule_known(struct audit_krule *krule) 5557 { 5558 return call_int_hook(audit_rule_known, krule); 5559 } 5560 5561 /** 5562 * security_audit_rule_free() - Free an LSM audit rule struct 5563 * @lsmrule: audit rule struct 5564 * 5565 * Deallocate the LSM audit rule structure previously allocated by 5566 * audit_rule_init(). 5567 */ 5568 void security_audit_rule_free(void *lsmrule) 5569 { 5570 call_void_hook(audit_rule_free, lsmrule); 5571 } 5572 5573 /** 5574 * security_audit_rule_match() - Check if a label matches an audit rule 5575 * @secid: security label 5576 * @field: LSM audit field 5577 * @op: matching operator 5578 * @lsmrule: audit rule 5579 * 5580 * Determine if given @secid matches a rule previously approved by 5581 * security_audit_rule_known(). 5582 * 5583 * Return: Returns 1 if secid matches the rule, 0 if it does not, -ERRNO on 5584 * failure. 5585 */ 5586 int security_audit_rule_match(u32 secid, u32 field, u32 op, void *lsmrule) 5587 { 5588 return call_int_hook(audit_rule_match, secid, field, op, lsmrule); 5589 } 5590 #endif /* CONFIG_AUDIT */ 5591 5592 #ifdef CONFIG_BPF_SYSCALL 5593 /** 5594 * security_bpf() - Check if the bpf syscall operation is allowed 5595 * @cmd: command 5596 * @attr: bpf attribute 5597 * @size: size 5598 * 5599 * Do a initial check for all bpf syscalls after the attribute is copied into 5600 * the kernel. The actual security module can implement their own rules to 5601 * check the specific cmd they need. 5602 * 5603 * Return: Returns 0 if permission is granted. 5604 */ 5605 int security_bpf(int cmd, union bpf_attr *attr, unsigned int size) 5606 { 5607 return call_int_hook(bpf, cmd, attr, size); 5608 } 5609 5610 /** 5611 * security_bpf_map() - Check if access to a bpf map is allowed 5612 * @map: bpf map 5613 * @fmode: mode 5614 * 5615 * Do a check when the kernel generates and returns a file descriptor for eBPF 5616 * maps. 5617 * 5618 * Return: Returns 0 if permission is granted. 5619 */ 5620 int security_bpf_map(struct bpf_map *map, fmode_t fmode) 5621 { 5622 return call_int_hook(bpf_map, map, fmode); 5623 } 5624 5625 /** 5626 * security_bpf_prog() - Check if access to a bpf program is allowed 5627 * @prog: bpf program 5628 * 5629 * Do a check when the kernel generates and returns a file descriptor for eBPF 5630 * programs. 5631 * 5632 * Return: Returns 0 if permission is granted. 5633 */ 5634 int security_bpf_prog(struct bpf_prog *prog) 5635 { 5636 return call_int_hook(bpf_prog, prog); 5637 } 5638 5639 /** 5640 * security_bpf_map_create() - Check if BPF map creation is allowed 5641 * @map: BPF map object 5642 * @attr: BPF syscall attributes used to create BPF map 5643 * @token: BPF token used to grant user access 5644 * 5645 * Do a check when the kernel creates a new BPF map. This is also the 5646 * point where LSM blob is allocated for LSMs that need them. 5647 * 5648 * Return: Returns 0 on success, error on failure. 5649 */ 5650 int security_bpf_map_create(struct bpf_map *map, union bpf_attr *attr, 5651 struct bpf_token *token) 5652 { 5653 return call_int_hook(bpf_map_create, map, attr, token); 5654 } 5655 5656 /** 5657 * security_bpf_prog_load() - Check if loading of BPF program is allowed 5658 * @prog: BPF program object 5659 * @attr: BPF syscall attributes used to create BPF program 5660 * @token: BPF token used to grant user access to BPF subsystem 5661 * 5662 * Perform an access control check when the kernel loads a BPF program and 5663 * allocates associated BPF program object. This hook is also responsible for 5664 * allocating any required LSM state for the BPF program. 5665 * 5666 * Return: Returns 0 on success, error on failure. 5667 */ 5668 int security_bpf_prog_load(struct bpf_prog *prog, union bpf_attr *attr, 5669 struct bpf_token *token) 5670 { 5671 return call_int_hook(bpf_prog_load, prog, attr, token); 5672 } 5673 5674 /** 5675 * security_bpf_token_create() - Check if creating of BPF token is allowed 5676 * @token: BPF token object 5677 * @attr: BPF syscall attributes used to create BPF token 5678 * @path: path pointing to BPF FS mount point from which BPF token is created 5679 * 5680 * Do a check when the kernel instantiates a new BPF token object from BPF FS 5681 * instance. This is also the point where LSM blob can be allocated for LSMs. 5682 * 5683 * Return: Returns 0 on success, error on failure. 5684 */ 5685 int security_bpf_token_create(struct bpf_token *token, union bpf_attr *attr, 5686 const struct path *path) 5687 { 5688 return call_int_hook(bpf_token_create, token, attr, path); 5689 } 5690 5691 /** 5692 * security_bpf_token_cmd() - Check if BPF token is allowed to delegate 5693 * requested BPF syscall command 5694 * @token: BPF token object 5695 * @cmd: BPF syscall command requested to be delegated by BPF token 5696 * 5697 * Do a check when the kernel decides whether provided BPF token should allow 5698 * delegation of requested BPF syscall command. 5699 * 5700 * Return: Returns 0 on success, error on failure. 5701 */ 5702 int security_bpf_token_cmd(const struct bpf_token *token, enum bpf_cmd cmd) 5703 { 5704 return call_int_hook(bpf_token_cmd, token, cmd); 5705 } 5706 5707 /** 5708 * security_bpf_token_capable() - Check if BPF token is allowed to delegate 5709 * requested BPF-related capability 5710 * @token: BPF token object 5711 * @cap: capabilities requested to be delegated by BPF token 5712 * 5713 * Do a check when the kernel decides whether provided BPF token should allow 5714 * delegation of requested BPF-related capabilities. 5715 * 5716 * Return: Returns 0 on success, error on failure. 5717 */ 5718 int security_bpf_token_capable(const struct bpf_token *token, int cap) 5719 { 5720 return call_int_hook(bpf_token_capable, token, cap); 5721 } 5722 5723 /** 5724 * security_bpf_map_free() - Free a bpf map's LSM blob 5725 * @map: bpf map 5726 * 5727 * Clean up the security information stored inside bpf map. 5728 */ 5729 void security_bpf_map_free(struct bpf_map *map) 5730 { 5731 call_void_hook(bpf_map_free, map); 5732 } 5733 5734 /** 5735 * security_bpf_prog_free() - Free a BPF program's LSM blob 5736 * @prog: BPF program struct 5737 * 5738 * Clean up the security information stored inside BPF program. 5739 */ 5740 void security_bpf_prog_free(struct bpf_prog *prog) 5741 { 5742 call_void_hook(bpf_prog_free, prog); 5743 } 5744 5745 /** 5746 * security_bpf_token_free() - Free a BPF token's LSM blob 5747 * @token: BPF token struct 5748 * 5749 * Clean up the security information stored inside BPF token. 5750 */ 5751 void security_bpf_token_free(struct bpf_token *token) 5752 { 5753 call_void_hook(bpf_token_free, token); 5754 } 5755 #endif /* CONFIG_BPF_SYSCALL */ 5756 5757 /** 5758 * security_locked_down() - Check if a kernel feature is allowed 5759 * @what: requested kernel feature 5760 * 5761 * Determine whether a kernel feature that potentially enables arbitrary code 5762 * execution in kernel space should be permitted. 5763 * 5764 * Return: Returns 0 if permission is granted. 5765 */ 5766 int security_locked_down(enum lockdown_reason what) 5767 { 5768 return call_int_hook(locked_down, what); 5769 } 5770 EXPORT_SYMBOL(security_locked_down); 5771 5772 /** 5773 * security_bdev_alloc() - Allocate a block device LSM blob 5774 * @bdev: block device 5775 * 5776 * Allocate and attach a security structure to @bdev->bd_security. The 5777 * security field is initialized to NULL when the bdev structure is 5778 * allocated. 5779 * 5780 * Return: Return 0 if operation was successful. 5781 */ 5782 int security_bdev_alloc(struct block_device *bdev) 5783 { 5784 int rc = 0; 5785 5786 rc = lsm_bdev_alloc(bdev); 5787 if (unlikely(rc)) 5788 return rc; 5789 5790 rc = call_int_hook(bdev_alloc_security, bdev); 5791 if (unlikely(rc)) 5792 security_bdev_free(bdev); 5793 5794 return rc; 5795 } 5796 EXPORT_SYMBOL(security_bdev_alloc); 5797 5798 /** 5799 * security_bdev_free() - Free a block device's LSM blob 5800 * @bdev: block device 5801 * 5802 * Deallocate the bdev security structure and set @bdev->bd_security to NULL. 5803 */ 5804 void security_bdev_free(struct block_device *bdev) 5805 { 5806 if (!bdev->bd_security) 5807 return; 5808 5809 call_void_hook(bdev_free_security, bdev); 5810 5811 kfree(bdev->bd_security); 5812 bdev->bd_security = NULL; 5813 } 5814 EXPORT_SYMBOL(security_bdev_free); 5815 5816 /** 5817 * security_bdev_setintegrity() - Set the device's integrity data 5818 * @bdev: block device 5819 * @type: type of integrity, e.g. hash digest, signature, etc 5820 * @value: the integrity value 5821 * @size: size of the integrity value 5822 * 5823 * Register a verified integrity measurement of a bdev with LSMs. 5824 * LSMs should free the previously saved data if @value is NULL. 5825 * Please note that the new hook should be invoked every time the security 5826 * information is updated to keep these data current. For example, in dm-verity, 5827 * if the mapping table is reloaded and configured to use a different dm-verity 5828 * target with a new roothash and signing information, the previously stored 5829 * data in the LSM blob will become obsolete. It is crucial to re-invoke the 5830 * hook to refresh these data and ensure they are up to date. This necessity 5831 * arises from the design of device-mapper, where a device-mapper device is 5832 * first created, and then targets are subsequently loaded into it. These 5833 * targets can be modified multiple times during the device's lifetime. 5834 * Therefore, while the LSM blob is allocated during the creation of the block 5835 * device, its actual contents are not initialized at this stage and can change 5836 * substantially over time. This includes alterations from data that the LSMs 5837 * 'trusts' to those they do not, making it essential to handle these changes 5838 * correctly. Failure to address this dynamic aspect could potentially allow 5839 * for bypassing LSM checks. 5840 * 5841 * Return: Returns 0 on success, negative values on failure. 5842 */ 5843 int security_bdev_setintegrity(struct block_device *bdev, 5844 enum lsm_integrity_type type, const void *value, 5845 size_t size) 5846 { 5847 return call_int_hook(bdev_setintegrity, bdev, type, value, size); 5848 } 5849 EXPORT_SYMBOL(security_bdev_setintegrity); 5850 5851 #ifdef CONFIG_PERF_EVENTS 5852 /** 5853 * security_perf_event_open() - Check if a perf event open is allowed 5854 * @attr: perf event attribute 5855 * @type: type of event 5856 * 5857 * Check whether the @type of perf_event_open syscall is allowed. 5858 * 5859 * Return: Returns 0 if permission is granted. 5860 */ 5861 int security_perf_event_open(struct perf_event_attr *attr, int type) 5862 { 5863 return call_int_hook(perf_event_open, attr, type); 5864 } 5865 5866 /** 5867 * security_perf_event_alloc() - Allocate a perf event LSM blob 5868 * @event: perf event 5869 * 5870 * Allocate and save perf_event security info. 5871 * 5872 * Return: Returns 0 on success, error on failure. 5873 */ 5874 int security_perf_event_alloc(struct perf_event *event) 5875 { 5876 int rc; 5877 5878 rc = lsm_blob_alloc(&event->security, blob_sizes.lbs_perf_event, 5879 GFP_KERNEL); 5880 if (rc) 5881 return rc; 5882 5883 rc = call_int_hook(perf_event_alloc, event); 5884 if (rc) { 5885 kfree(event->security); 5886 event->security = NULL; 5887 } 5888 return rc; 5889 } 5890 5891 /** 5892 * security_perf_event_free() - Free a perf event LSM blob 5893 * @event: perf event 5894 * 5895 * Release (free) perf_event security info. 5896 */ 5897 void security_perf_event_free(struct perf_event *event) 5898 { 5899 kfree(event->security); 5900 event->security = NULL; 5901 } 5902 5903 /** 5904 * security_perf_event_read() - Check if reading a perf event label is allowed 5905 * @event: perf event 5906 * 5907 * Read perf_event security info if allowed. 5908 * 5909 * Return: Returns 0 if permission is granted. 5910 */ 5911 int security_perf_event_read(struct perf_event *event) 5912 { 5913 return call_int_hook(perf_event_read, event); 5914 } 5915 5916 /** 5917 * security_perf_event_write() - Check if writing a perf event label is allowed 5918 * @event: perf event 5919 * 5920 * Write perf_event security info if allowed. 5921 * 5922 * Return: Returns 0 if permission is granted. 5923 */ 5924 int security_perf_event_write(struct perf_event *event) 5925 { 5926 return call_int_hook(perf_event_write, event); 5927 } 5928 #endif /* CONFIG_PERF_EVENTS */ 5929 5930 #ifdef CONFIG_IO_URING 5931 /** 5932 * security_uring_override_creds() - Check if overriding creds is allowed 5933 * @new: new credentials 5934 * 5935 * Check if the current task, executing an io_uring operation, is allowed to 5936 * override it's credentials with @new. 5937 * 5938 * Return: Returns 0 if permission is granted. 5939 */ 5940 int security_uring_override_creds(const struct cred *new) 5941 { 5942 return call_int_hook(uring_override_creds, new); 5943 } 5944 5945 /** 5946 * security_uring_sqpoll() - Check if IORING_SETUP_SQPOLL is allowed 5947 * 5948 * Check whether the current task is allowed to spawn a io_uring polling thread 5949 * (IORING_SETUP_SQPOLL). 5950 * 5951 * Return: Returns 0 if permission is granted. 5952 */ 5953 int security_uring_sqpoll(void) 5954 { 5955 return call_int_hook(uring_sqpoll); 5956 } 5957 5958 /** 5959 * security_uring_cmd() - Check if a io_uring passthrough command is allowed 5960 * @ioucmd: command 5961 * 5962 * Check whether the file_operations uring_cmd is allowed to run. 5963 * 5964 * Return: Returns 0 if permission is granted. 5965 */ 5966 int security_uring_cmd(struct io_uring_cmd *ioucmd) 5967 { 5968 return call_int_hook(uring_cmd, ioucmd); 5969 } 5970 #endif /* CONFIG_IO_URING */ 5971 5972 /** 5973 * security_initramfs_populated() - Notify LSMs that initramfs has been loaded 5974 * 5975 * Tells the LSMs the initramfs has been unpacked into the rootfs. 5976 */ 5977 void security_initramfs_populated(void) 5978 { 5979 call_void_hook(initramfs_populated); 5980 } 5981