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/mman.h> 23 #include <linux/mount.h> 24 #include <linux/personality.h> 25 #include <linux/backing-dev.h> 26 #include <linux/string.h> 27 #include <linux/xattr.h> 28 #include <linux/msg.h> 29 #include <linux/overflow.h> 30 #include <linux/perf_event.h> 31 #include <linux/fs.h> 32 #include <net/flow.h> 33 #include <net/sock.h> 34 35 #define SECURITY_HOOK_ACTIVE_KEY(HOOK, IDX) security_hook_active_##HOOK##_##IDX 36 37 /* 38 * Identifier for the LSM static calls. 39 * HOOK is an LSM hook as defined in linux/lsm_hookdefs.h 40 * IDX is the index of the static call. 0 <= NUM < MAX_LSM_COUNT 41 */ 42 #define LSM_STATIC_CALL(HOOK, IDX) lsm_static_call_##HOOK##_##IDX 43 44 /* 45 * Call the macro M for each LSM hook MAX_LSM_COUNT times. 46 */ 47 #define LSM_LOOP_UNROLL(M, ...) \ 48 do { \ 49 UNROLL(MAX_LSM_COUNT, M, __VA_ARGS__) \ 50 } while (0) 51 52 #define LSM_DEFINE_UNROLL(M, ...) UNROLL(MAX_LSM_COUNT, M, __VA_ARGS__) 53 54 /* 55 * These are descriptions of the reasons that can be passed to the 56 * security_locked_down() LSM hook. Placing this array here allows 57 * all security modules to use the same descriptions for auditing 58 * purposes. 59 */ 60 const char *const lockdown_reasons[LOCKDOWN_CONFIDENTIALITY_MAX + 1] = { 61 [LOCKDOWN_NONE] = "none", 62 [LOCKDOWN_MODULE_SIGNATURE] = "unsigned module loading", 63 [LOCKDOWN_DEV_MEM] = "/dev/mem,kmem,port", 64 [LOCKDOWN_EFI_TEST] = "/dev/efi_test access", 65 [LOCKDOWN_KEXEC] = "kexec of unsigned images", 66 [LOCKDOWN_HIBERNATION] = "hibernation", 67 [LOCKDOWN_PCI_ACCESS] = "direct PCI access", 68 [LOCKDOWN_IOPORT] = "raw io port access", 69 [LOCKDOWN_MSR] = "raw MSR access", 70 [LOCKDOWN_ACPI_TABLES] = "modifying ACPI tables", 71 [LOCKDOWN_DEVICE_TREE] = "modifying device tree contents", 72 [LOCKDOWN_PCMCIA_CIS] = "direct PCMCIA CIS storage", 73 [LOCKDOWN_TIOCSSERIAL] = "reconfiguration of serial port IO", 74 [LOCKDOWN_MODULE_PARAMETERS] = "unsafe module parameters", 75 [LOCKDOWN_MMIOTRACE] = "unsafe mmio", 76 [LOCKDOWN_DEBUGFS] = "debugfs access", 77 [LOCKDOWN_XMON_WR] = "xmon write access", 78 [LOCKDOWN_BPF_WRITE_USER] = "use of bpf to write user RAM", 79 [LOCKDOWN_DBG_WRITE_KERNEL] = "use of kgdb/kdb to write kernel RAM", 80 [LOCKDOWN_RTAS_ERROR_INJECTION] = "RTAS error injection", 81 [LOCKDOWN_INTEGRITY_MAX] = "integrity", 82 [LOCKDOWN_KCORE] = "/proc/kcore access", 83 [LOCKDOWN_KPROBES] = "use of kprobes", 84 [LOCKDOWN_BPF_READ_KERNEL] = "use of bpf to read kernel RAM", 85 [LOCKDOWN_DBG_READ_KERNEL] = "use of kgdb/kdb to read kernel RAM", 86 [LOCKDOWN_PERF] = "unsafe use of perf", 87 [LOCKDOWN_TRACEFS] = "use of tracefs", 88 [LOCKDOWN_XMON_RW] = "xmon read and write access", 89 [LOCKDOWN_XFRM_SECRET] = "xfrm SA secret", 90 [LOCKDOWN_CONFIDENTIALITY_MAX] = "confidentiality", 91 }; 92 93 static BLOCKING_NOTIFIER_HEAD(blocking_lsm_notifier_chain); 94 95 static struct kmem_cache *lsm_file_cache; 96 static struct kmem_cache *lsm_inode_cache; 97 98 char *lsm_names; 99 static struct lsm_blob_sizes blob_sizes __ro_after_init; 100 101 /* Boot-time LSM user choice */ 102 static __initdata const char *chosen_lsm_order; 103 static __initdata const char *chosen_major_lsm; 104 105 static __initconst const char *const builtin_lsm_order = CONFIG_LSM; 106 107 /* Ordered list of LSMs to initialize. */ 108 static __initdata struct lsm_info *ordered_lsms[MAX_LSM_COUNT + 1]; 109 static __initdata struct lsm_info *exclusive; 110 111 #ifdef CONFIG_HAVE_STATIC_CALL 112 #define LSM_HOOK_TRAMP(NAME, NUM) \ 113 &STATIC_CALL_TRAMP(LSM_STATIC_CALL(NAME, NUM)) 114 #else 115 #define LSM_HOOK_TRAMP(NAME, NUM) NULL 116 #endif 117 118 /* 119 * Define static calls and static keys for each LSM hook. 120 */ 121 #define DEFINE_LSM_STATIC_CALL(NUM, NAME, RET, ...) \ 122 DEFINE_STATIC_CALL_NULL(LSM_STATIC_CALL(NAME, NUM), \ 123 *((RET(*)(__VA_ARGS__))NULL)); \ 124 DEFINE_STATIC_KEY_FALSE(SECURITY_HOOK_ACTIVE_KEY(NAME, NUM)); 125 126 #define LSM_HOOK(RET, DEFAULT, NAME, ...) \ 127 LSM_DEFINE_UNROLL(DEFINE_LSM_STATIC_CALL, NAME, RET, __VA_ARGS__) 128 #include <linux/lsm_hook_defs.h> 129 #undef LSM_HOOK 130 #undef DEFINE_LSM_STATIC_CALL 131 132 /* 133 * Initialise a table of static calls for each LSM hook. 134 * DEFINE_STATIC_CALL_NULL invocation above generates a key (STATIC_CALL_KEY) 135 * and a trampoline (STATIC_CALL_TRAMP) which are used to call 136 * __static_call_update when updating the static call. 137 * 138 * The static calls table is used by early LSMs, some architectures can fault on 139 * unaligned accesses and the fault handling code may not be ready by then. 140 * Thus, the static calls table should be aligned to avoid any unhandled faults 141 * in early init. 142 */ 143 struct lsm_static_calls_table 144 static_calls_table __ro_after_init __aligned(sizeof(u64)) = { 145 #define INIT_LSM_STATIC_CALL(NUM, NAME) \ 146 (struct lsm_static_call) { \ 147 .key = &STATIC_CALL_KEY(LSM_STATIC_CALL(NAME, NUM)), \ 148 .trampoline = LSM_HOOK_TRAMP(NAME, NUM), \ 149 .active = &SECURITY_HOOK_ACTIVE_KEY(NAME, NUM), \ 150 }, 151 #define LSM_HOOK(RET, DEFAULT, NAME, ...) \ 152 .NAME = { \ 153 LSM_DEFINE_UNROLL(INIT_LSM_STATIC_CALL, NAME) \ 154 }, 155 #include <linux/lsm_hook_defs.h> 156 #undef LSM_HOOK 157 #undef INIT_LSM_STATIC_CALL 158 }; 159 160 static __initdata bool debug; 161 #define init_debug(...) \ 162 do { \ 163 if (debug) \ 164 pr_info(__VA_ARGS__); \ 165 } while (0) 166 167 static bool __init is_enabled(struct lsm_info *lsm) 168 { 169 if (!lsm->enabled) 170 return false; 171 172 return *lsm->enabled; 173 } 174 175 /* Mark an LSM's enabled flag. */ 176 static int lsm_enabled_true __initdata = 1; 177 static int lsm_enabled_false __initdata = 0; 178 static void __init set_enabled(struct lsm_info *lsm, bool enabled) 179 { 180 /* 181 * When an LSM hasn't configured an enable variable, we can use 182 * a hard-coded location for storing the default enabled state. 183 */ 184 if (!lsm->enabled) { 185 if (enabled) 186 lsm->enabled = &lsm_enabled_true; 187 else 188 lsm->enabled = &lsm_enabled_false; 189 } else if (lsm->enabled == &lsm_enabled_true) { 190 if (!enabled) 191 lsm->enabled = &lsm_enabled_false; 192 } else if (lsm->enabled == &lsm_enabled_false) { 193 if (enabled) 194 lsm->enabled = &lsm_enabled_true; 195 } else { 196 *lsm->enabled = enabled; 197 } 198 } 199 200 /* Is an LSM already listed in the ordered LSMs list? */ 201 static bool __init exists_ordered_lsm(struct lsm_info *lsm) 202 { 203 struct lsm_info **check; 204 205 for (check = ordered_lsms; *check; check++) 206 if (*check == lsm) 207 return true; 208 209 return false; 210 } 211 212 /* Append an LSM to the list of ordered LSMs to initialize. */ 213 static int last_lsm __initdata; 214 static void __init append_ordered_lsm(struct lsm_info *lsm, const char *from) 215 { 216 /* Ignore duplicate selections. */ 217 if (exists_ordered_lsm(lsm)) 218 return; 219 220 if (WARN(last_lsm == MAX_LSM_COUNT, "%s: out of LSM static calls!?\n", from)) 221 return; 222 223 /* Enable this LSM, if it is not already set. */ 224 if (!lsm->enabled) 225 lsm->enabled = &lsm_enabled_true; 226 ordered_lsms[last_lsm++] = lsm; 227 228 init_debug("%s ordered: %s (%s)\n", from, lsm->name, 229 is_enabled(lsm) ? "enabled" : "disabled"); 230 } 231 232 /* Is an LSM allowed to be initialized? */ 233 static bool __init lsm_allowed(struct lsm_info *lsm) 234 { 235 /* Skip if the LSM is disabled. */ 236 if (!is_enabled(lsm)) 237 return false; 238 239 /* Not allowed if another exclusive LSM already initialized. */ 240 if ((lsm->flags & LSM_FLAG_EXCLUSIVE) && exclusive) { 241 init_debug("exclusive disabled: %s\n", lsm->name); 242 return false; 243 } 244 245 return true; 246 } 247 248 static void __init lsm_set_blob_size(int *need, int *lbs) 249 { 250 int offset; 251 252 if (*need <= 0) 253 return; 254 255 offset = ALIGN(*lbs, sizeof(void *)); 256 *lbs = offset + *need; 257 *need = offset; 258 } 259 260 static void __init lsm_set_blob_sizes(struct lsm_blob_sizes *needed) 261 { 262 if (!needed) 263 return; 264 265 lsm_set_blob_size(&needed->lbs_cred, &blob_sizes.lbs_cred); 266 lsm_set_blob_size(&needed->lbs_file, &blob_sizes.lbs_file); 267 lsm_set_blob_size(&needed->lbs_ib, &blob_sizes.lbs_ib); 268 /* 269 * The inode blob gets an rcu_head in addition to 270 * what the modules might need. 271 */ 272 if (needed->lbs_inode && blob_sizes.lbs_inode == 0) 273 blob_sizes.lbs_inode = sizeof(struct rcu_head); 274 lsm_set_blob_size(&needed->lbs_inode, &blob_sizes.lbs_inode); 275 lsm_set_blob_size(&needed->lbs_ipc, &blob_sizes.lbs_ipc); 276 lsm_set_blob_size(&needed->lbs_key, &blob_sizes.lbs_key); 277 lsm_set_blob_size(&needed->lbs_msg_msg, &blob_sizes.lbs_msg_msg); 278 lsm_set_blob_size(&needed->lbs_perf_event, &blob_sizes.lbs_perf_event); 279 lsm_set_blob_size(&needed->lbs_sock, &blob_sizes.lbs_sock); 280 lsm_set_blob_size(&needed->lbs_superblock, &blob_sizes.lbs_superblock); 281 lsm_set_blob_size(&needed->lbs_task, &blob_sizes.lbs_task); 282 lsm_set_blob_size(&needed->lbs_tun_dev, &blob_sizes.lbs_tun_dev); 283 lsm_set_blob_size(&needed->lbs_xattr_count, 284 &blob_sizes.lbs_xattr_count); 285 lsm_set_blob_size(&needed->lbs_bdev, &blob_sizes.lbs_bdev); 286 } 287 288 /* Prepare LSM for initialization. */ 289 static void __init prepare_lsm(struct lsm_info *lsm) 290 { 291 int enabled = lsm_allowed(lsm); 292 293 /* Record enablement (to handle any following exclusive LSMs). */ 294 set_enabled(lsm, enabled); 295 296 /* If enabled, do pre-initialization work. */ 297 if (enabled) { 298 if ((lsm->flags & LSM_FLAG_EXCLUSIVE) && !exclusive) { 299 exclusive = lsm; 300 init_debug("exclusive chosen: %s\n", lsm->name); 301 } 302 303 lsm_set_blob_sizes(lsm->blobs); 304 } 305 } 306 307 /* Initialize a given LSM, if it is enabled. */ 308 static void __init initialize_lsm(struct lsm_info *lsm) 309 { 310 if (is_enabled(lsm)) { 311 int ret; 312 313 init_debug("initializing %s\n", lsm->name); 314 ret = lsm->init(); 315 WARN(ret, "%s failed to initialize: %d\n", lsm->name, ret); 316 } 317 } 318 319 /* 320 * Current index to use while initializing the lsm id list. 321 */ 322 u32 lsm_active_cnt __ro_after_init; 323 const struct lsm_id *lsm_idlist[MAX_LSM_COUNT]; 324 325 /* Populate ordered LSMs list from comma-separated LSM name list. */ 326 static void __init ordered_lsm_parse(const char *order, const char *origin) 327 { 328 struct lsm_info *lsm; 329 char *sep, *name, *next; 330 331 /* LSM_ORDER_FIRST is always first. */ 332 for (lsm = __start_lsm_info; lsm < __end_lsm_info; lsm++) { 333 if (lsm->order == LSM_ORDER_FIRST) 334 append_ordered_lsm(lsm, " first"); 335 } 336 337 /* Process "security=", if given. */ 338 if (chosen_major_lsm) { 339 struct lsm_info *major; 340 341 /* 342 * To match the original "security=" behavior, this 343 * explicitly does NOT fallback to another Legacy Major 344 * if the selected one was separately disabled: disable 345 * all non-matching Legacy Major LSMs. 346 */ 347 for (major = __start_lsm_info; major < __end_lsm_info; 348 major++) { 349 if ((major->flags & LSM_FLAG_LEGACY_MAJOR) && 350 strcmp(major->name, chosen_major_lsm) != 0) { 351 set_enabled(major, false); 352 init_debug("security=%s disabled: %s (only one legacy major LSM)\n", 353 chosen_major_lsm, major->name); 354 } 355 } 356 } 357 358 sep = kstrdup(order, GFP_KERNEL); 359 next = sep; 360 /* Walk the list, looking for matching LSMs. */ 361 while ((name = strsep(&next, ",")) != NULL) { 362 bool found = false; 363 364 for (lsm = __start_lsm_info; lsm < __end_lsm_info; lsm++) { 365 if (strcmp(lsm->name, name) == 0) { 366 if (lsm->order == LSM_ORDER_MUTABLE) 367 append_ordered_lsm(lsm, origin); 368 found = true; 369 } 370 } 371 372 if (!found) 373 init_debug("%s ignored: %s (not built into kernel)\n", 374 origin, name); 375 } 376 377 /* Process "security=", if given. */ 378 if (chosen_major_lsm) { 379 for (lsm = __start_lsm_info; lsm < __end_lsm_info; lsm++) { 380 if (exists_ordered_lsm(lsm)) 381 continue; 382 if (strcmp(lsm->name, chosen_major_lsm) == 0) 383 append_ordered_lsm(lsm, "security="); 384 } 385 } 386 387 /* LSM_ORDER_LAST is always last. */ 388 for (lsm = __start_lsm_info; lsm < __end_lsm_info; lsm++) { 389 if (lsm->order == LSM_ORDER_LAST) 390 append_ordered_lsm(lsm, " last"); 391 } 392 393 /* Disable all LSMs not in the ordered list. */ 394 for (lsm = __start_lsm_info; lsm < __end_lsm_info; lsm++) { 395 if (exists_ordered_lsm(lsm)) 396 continue; 397 set_enabled(lsm, false); 398 init_debug("%s skipped: %s (not in requested order)\n", 399 origin, lsm->name); 400 } 401 402 kfree(sep); 403 } 404 405 static void __init lsm_static_call_init(struct security_hook_list *hl) 406 { 407 struct lsm_static_call *scall = hl->scalls; 408 int i; 409 410 for (i = 0; i < MAX_LSM_COUNT; i++) { 411 /* Update the first static call that is not used yet */ 412 if (!scall->hl) { 413 __static_call_update(scall->key, scall->trampoline, 414 hl->hook.lsm_func_addr); 415 scall->hl = hl; 416 static_branch_enable(scall->active); 417 return; 418 } 419 scall++; 420 } 421 panic("%s - Ran out of static slots.\n", __func__); 422 } 423 424 static void __init lsm_early_cred(struct cred *cred); 425 static void __init lsm_early_task(struct task_struct *task); 426 427 static int lsm_append(const char *new, char **result); 428 429 static void __init report_lsm_order(void) 430 { 431 struct lsm_info **lsm, *early; 432 int first = 0; 433 434 pr_info("initializing lsm="); 435 436 /* Report each enabled LSM name, comma separated. */ 437 for (early = __start_early_lsm_info; 438 early < __end_early_lsm_info; early++) 439 if (is_enabled(early)) 440 pr_cont("%s%s", first++ == 0 ? "" : ",", early->name); 441 for (lsm = ordered_lsms; *lsm; lsm++) 442 if (is_enabled(*lsm)) 443 pr_cont("%s%s", first++ == 0 ? "" : ",", (*lsm)->name); 444 445 pr_cont("\n"); 446 } 447 448 static void __init ordered_lsm_init(void) 449 { 450 struct lsm_info **lsm; 451 452 if (chosen_lsm_order) { 453 if (chosen_major_lsm) { 454 pr_warn("security=%s is ignored because it is superseded by lsm=%s\n", 455 chosen_major_lsm, chosen_lsm_order); 456 chosen_major_lsm = NULL; 457 } 458 ordered_lsm_parse(chosen_lsm_order, "cmdline"); 459 } else 460 ordered_lsm_parse(builtin_lsm_order, "builtin"); 461 462 for (lsm = ordered_lsms; *lsm; lsm++) 463 prepare_lsm(*lsm); 464 465 report_lsm_order(); 466 467 init_debug("cred blob size = %d\n", blob_sizes.lbs_cred); 468 init_debug("file blob size = %d\n", blob_sizes.lbs_file); 469 init_debug("ib blob size = %d\n", blob_sizes.lbs_ib); 470 init_debug("inode blob size = %d\n", blob_sizes.lbs_inode); 471 init_debug("ipc blob size = %d\n", blob_sizes.lbs_ipc); 472 #ifdef CONFIG_KEYS 473 init_debug("key blob size = %d\n", blob_sizes.lbs_key); 474 #endif /* CONFIG_KEYS */ 475 init_debug("msg_msg blob size = %d\n", blob_sizes.lbs_msg_msg); 476 init_debug("sock blob size = %d\n", blob_sizes.lbs_sock); 477 init_debug("superblock blob size = %d\n", blob_sizes.lbs_superblock); 478 init_debug("perf event blob size = %d\n", blob_sizes.lbs_perf_event); 479 init_debug("task blob size = %d\n", blob_sizes.lbs_task); 480 init_debug("tun device blob size = %d\n", blob_sizes.lbs_tun_dev); 481 init_debug("xattr slots = %d\n", blob_sizes.lbs_xattr_count); 482 init_debug("bdev blob size = %d\n", blob_sizes.lbs_bdev); 483 484 /* 485 * Create any kmem_caches needed for blobs 486 */ 487 if (blob_sizes.lbs_file) 488 lsm_file_cache = kmem_cache_create("lsm_file_cache", 489 blob_sizes.lbs_file, 0, 490 SLAB_PANIC, NULL); 491 if (blob_sizes.lbs_inode) 492 lsm_inode_cache = kmem_cache_create("lsm_inode_cache", 493 blob_sizes.lbs_inode, 0, 494 SLAB_PANIC, NULL); 495 496 lsm_early_cred((struct cred *) current->cred); 497 lsm_early_task(current); 498 for (lsm = ordered_lsms; *lsm; lsm++) 499 initialize_lsm(*lsm); 500 } 501 502 int __init early_security_init(void) 503 { 504 struct lsm_info *lsm; 505 506 for (lsm = __start_early_lsm_info; lsm < __end_early_lsm_info; lsm++) { 507 if (!lsm->enabled) 508 lsm->enabled = &lsm_enabled_true; 509 prepare_lsm(lsm); 510 initialize_lsm(lsm); 511 } 512 513 return 0; 514 } 515 516 /** 517 * security_init - initializes the security framework 518 * 519 * This should be called early in the kernel initialization sequence. 520 */ 521 int __init security_init(void) 522 { 523 struct lsm_info *lsm; 524 525 init_debug("legacy security=%s\n", chosen_major_lsm ? : " *unspecified*"); 526 init_debug(" CONFIG_LSM=%s\n", builtin_lsm_order); 527 init_debug("boot arg lsm=%s\n", chosen_lsm_order ? : " *unspecified*"); 528 529 /* 530 * Append the names of the early LSM modules now that kmalloc() is 531 * available 532 */ 533 for (lsm = __start_early_lsm_info; lsm < __end_early_lsm_info; lsm++) { 534 init_debug(" early started: %s (%s)\n", lsm->name, 535 is_enabled(lsm) ? "enabled" : "disabled"); 536 if (lsm->enabled) 537 lsm_append(lsm->name, &lsm_names); 538 } 539 540 /* Load LSMs in specified order. */ 541 ordered_lsm_init(); 542 543 return 0; 544 } 545 546 /* Save user chosen LSM */ 547 static int __init choose_major_lsm(char *str) 548 { 549 chosen_major_lsm = str; 550 return 1; 551 } 552 __setup("security=", choose_major_lsm); 553 554 /* Explicitly choose LSM initialization order. */ 555 static int __init choose_lsm_order(char *str) 556 { 557 chosen_lsm_order = str; 558 return 1; 559 } 560 __setup("lsm=", choose_lsm_order); 561 562 /* Enable LSM order debugging. */ 563 static int __init enable_debug(char *str) 564 { 565 debug = true; 566 return 1; 567 } 568 __setup("lsm.debug", enable_debug); 569 570 static bool match_last_lsm(const char *list, const char *lsm) 571 { 572 const char *last; 573 574 if (WARN_ON(!list || !lsm)) 575 return false; 576 last = strrchr(list, ','); 577 if (last) 578 /* Pass the comma, strcmp() will check for '\0' */ 579 last++; 580 else 581 last = list; 582 return !strcmp(last, lsm); 583 } 584 585 static int lsm_append(const char *new, char **result) 586 { 587 char *cp; 588 589 if (*result == NULL) { 590 *result = kstrdup(new, GFP_KERNEL); 591 if (*result == NULL) 592 return -ENOMEM; 593 } else { 594 /* Check if it is the last registered name */ 595 if (match_last_lsm(*result, new)) 596 return 0; 597 cp = kasprintf(GFP_KERNEL, "%s,%s", *result, new); 598 if (cp == NULL) 599 return -ENOMEM; 600 kfree(*result); 601 *result = cp; 602 } 603 return 0; 604 } 605 606 /** 607 * security_add_hooks - Add a modules hooks to the hook lists. 608 * @hooks: the hooks to add 609 * @count: the number of hooks to add 610 * @lsmid: the identification information for the security module 611 * 612 * Each LSM has to register its hooks with the infrastructure. 613 */ 614 void __init security_add_hooks(struct security_hook_list *hooks, int count, 615 const struct lsm_id *lsmid) 616 { 617 int i; 618 619 /* 620 * A security module may call security_add_hooks() more 621 * than once during initialization, and LSM initialization 622 * is serialized. Landlock is one such case. 623 * Look at the previous entry, if there is one, for duplication. 624 */ 625 if (lsm_active_cnt == 0 || lsm_idlist[lsm_active_cnt - 1] != lsmid) { 626 if (lsm_active_cnt >= MAX_LSM_COUNT) 627 panic("%s Too many LSMs registered.\n", __func__); 628 lsm_idlist[lsm_active_cnt++] = lsmid; 629 } 630 631 for (i = 0; i < count; i++) { 632 hooks[i].lsmid = lsmid; 633 lsm_static_call_init(&hooks[i]); 634 } 635 636 /* 637 * Don't try to append during early_security_init(), we'll come back 638 * and fix this up afterwards. 639 */ 640 if (slab_is_available()) { 641 if (lsm_append(lsmid->name, &lsm_names) < 0) 642 panic("%s - Cannot get early memory.\n", __func__); 643 } 644 } 645 646 int call_blocking_lsm_notifier(enum lsm_event event, void *data) 647 { 648 return blocking_notifier_call_chain(&blocking_lsm_notifier_chain, 649 event, data); 650 } 651 EXPORT_SYMBOL(call_blocking_lsm_notifier); 652 653 int register_blocking_lsm_notifier(struct notifier_block *nb) 654 { 655 return blocking_notifier_chain_register(&blocking_lsm_notifier_chain, 656 nb); 657 } 658 EXPORT_SYMBOL(register_blocking_lsm_notifier); 659 660 int unregister_blocking_lsm_notifier(struct notifier_block *nb) 661 { 662 return blocking_notifier_chain_unregister(&blocking_lsm_notifier_chain, 663 nb); 664 } 665 EXPORT_SYMBOL(unregister_blocking_lsm_notifier); 666 667 /** 668 * lsm_blob_alloc - allocate a composite blob 669 * @dest: the destination for the blob 670 * @size: the size of the blob 671 * @gfp: allocation type 672 * 673 * Allocate a blob for all the modules 674 * 675 * Returns 0, or -ENOMEM if memory can't be allocated. 676 */ 677 static int lsm_blob_alloc(void **dest, size_t size, gfp_t gfp) 678 { 679 if (size == 0) { 680 *dest = NULL; 681 return 0; 682 } 683 684 *dest = kzalloc(size, gfp); 685 if (*dest == NULL) 686 return -ENOMEM; 687 return 0; 688 } 689 690 /** 691 * lsm_cred_alloc - allocate a composite cred blob 692 * @cred: the cred that needs a blob 693 * @gfp: allocation type 694 * 695 * Allocate the cred blob for all the modules 696 * 697 * Returns 0, or -ENOMEM if memory can't be allocated. 698 */ 699 static int lsm_cred_alloc(struct cred *cred, gfp_t gfp) 700 { 701 return lsm_blob_alloc(&cred->security, blob_sizes.lbs_cred, gfp); 702 } 703 704 /** 705 * lsm_early_cred - during initialization allocate a composite cred blob 706 * @cred: the cred that needs a blob 707 * 708 * Allocate the cred blob for all the modules 709 */ 710 static void __init lsm_early_cred(struct cred *cred) 711 { 712 int rc = lsm_cred_alloc(cred, GFP_KERNEL); 713 714 if (rc) 715 panic("%s: Early cred alloc failed.\n", __func__); 716 } 717 718 /** 719 * lsm_file_alloc - allocate a composite file blob 720 * @file: the file that needs a blob 721 * 722 * Allocate the file blob for all the modules 723 * 724 * Returns 0, or -ENOMEM if memory can't be allocated. 725 */ 726 static int lsm_file_alloc(struct file *file) 727 { 728 if (!lsm_file_cache) { 729 file->f_security = NULL; 730 return 0; 731 } 732 733 file->f_security = kmem_cache_zalloc(lsm_file_cache, GFP_KERNEL); 734 if (file->f_security == NULL) 735 return -ENOMEM; 736 return 0; 737 } 738 739 /** 740 * lsm_inode_alloc - allocate a composite inode blob 741 * @inode: the inode that needs a blob 742 * @gfp: allocation flags 743 * 744 * Allocate the inode blob for all the modules 745 * 746 * Returns 0, or -ENOMEM if memory can't be allocated. 747 */ 748 static int lsm_inode_alloc(struct inode *inode, gfp_t gfp) 749 { 750 if (!lsm_inode_cache) { 751 inode->i_security = NULL; 752 return 0; 753 } 754 755 inode->i_security = kmem_cache_zalloc(lsm_inode_cache, gfp); 756 if (inode->i_security == NULL) 757 return -ENOMEM; 758 return 0; 759 } 760 761 /** 762 * lsm_task_alloc - allocate a composite task blob 763 * @task: the task that needs a blob 764 * 765 * Allocate the task blob for all the modules 766 * 767 * Returns 0, or -ENOMEM if memory can't be allocated. 768 */ 769 static int lsm_task_alloc(struct task_struct *task) 770 { 771 return lsm_blob_alloc(&task->security, blob_sizes.lbs_task, GFP_KERNEL); 772 } 773 774 /** 775 * lsm_ipc_alloc - allocate a composite ipc blob 776 * @kip: the ipc that needs a blob 777 * 778 * Allocate the ipc blob for all the modules 779 * 780 * Returns 0, or -ENOMEM if memory can't be allocated. 781 */ 782 static int lsm_ipc_alloc(struct kern_ipc_perm *kip) 783 { 784 return lsm_blob_alloc(&kip->security, blob_sizes.lbs_ipc, GFP_KERNEL); 785 } 786 787 #ifdef CONFIG_KEYS 788 /** 789 * lsm_key_alloc - allocate a composite key blob 790 * @key: the key that needs a blob 791 * 792 * Allocate the key blob for all the modules 793 * 794 * Returns 0, or -ENOMEM if memory can't be allocated. 795 */ 796 static int lsm_key_alloc(struct key *key) 797 { 798 return lsm_blob_alloc(&key->security, blob_sizes.lbs_key, GFP_KERNEL); 799 } 800 #endif /* CONFIG_KEYS */ 801 802 /** 803 * lsm_msg_msg_alloc - allocate a composite msg_msg blob 804 * @mp: the msg_msg that needs a blob 805 * 806 * Allocate the ipc blob for all the modules 807 * 808 * Returns 0, or -ENOMEM if memory can't be allocated. 809 */ 810 static int lsm_msg_msg_alloc(struct msg_msg *mp) 811 { 812 return lsm_blob_alloc(&mp->security, blob_sizes.lbs_msg_msg, 813 GFP_KERNEL); 814 } 815 816 /** 817 * lsm_bdev_alloc - allocate a composite block_device blob 818 * @bdev: the block_device that needs a blob 819 * 820 * Allocate the block_device blob for all the modules 821 * 822 * Returns 0, or -ENOMEM if memory can't be allocated. 823 */ 824 static int lsm_bdev_alloc(struct block_device *bdev) 825 { 826 if (blob_sizes.lbs_bdev == 0) { 827 bdev->bd_security = NULL; 828 return 0; 829 } 830 831 bdev->bd_security = kzalloc(blob_sizes.lbs_bdev, GFP_KERNEL); 832 if (!bdev->bd_security) 833 return -ENOMEM; 834 835 return 0; 836 } 837 838 /** 839 * lsm_early_task - during initialization allocate a composite task blob 840 * @task: the task that needs a blob 841 * 842 * Allocate the task blob for all the modules 843 */ 844 static void __init lsm_early_task(struct task_struct *task) 845 { 846 int rc = lsm_task_alloc(task); 847 848 if (rc) 849 panic("%s: Early task alloc failed.\n", __func__); 850 } 851 852 /** 853 * lsm_superblock_alloc - allocate a composite superblock blob 854 * @sb: the superblock that needs a blob 855 * 856 * Allocate the superblock blob for all the modules 857 * 858 * Returns 0, or -ENOMEM if memory can't be allocated. 859 */ 860 static int lsm_superblock_alloc(struct super_block *sb) 861 { 862 return lsm_blob_alloc(&sb->s_security, blob_sizes.lbs_superblock, 863 GFP_KERNEL); 864 } 865 866 /** 867 * lsm_fill_user_ctx - Fill a user space lsm_ctx structure 868 * @uctx: a userspace LSM context to be filled 869 * @uctx_len: available uctx size (input), used uctx size (output) 870 * @val: the new LSM context value 871 * @val_len: the size of the new LSM context value 872 * @id: LSM id 873 * @flags: LSM defined flags 874 * 875 * Fill all of the fields in a userspace lsm_ctx structure. If @uctx is NULL 876 * simply calculate the required size to output via @utc_len and return 877 * success. 878 * 879 * Returns 0 on success, -E2BIG if userspace buffer is not large enough, 880 * -EFAULT on a copyout error, -ENOMEM if memory can't be allocated. 881 */ 882 int lsm_fill_user_ctx(struct lsm_ctx __user *uctx, u32 *uctx_len, 883 void *val, size_t val_len, 884 u64 id, u64 flags) 885 { 886 struct lsm_ctx *nctx = NULL; 887 size_t nctx_len; 888 int rc = 0; 889 890 nctx_len = ALIGN(struct_size(nctx, ctx, val_len), sizeof(void *)); 891 if (nctx_len > *uctx_len) { 892 rc = -E2BIG; 893 goto out; 894 } 895 896 /* no buffer - return success/0 and set @uctx_len to the req size */ 897 if (!uctx) 898 goto out; 899 900 nctx = kzalloc(nctx_len, GFP_KERNEL); 901 if (nctx == NULL) { 902 rc = -ENOMEM; 903 goto out; 904 } 905 nctx->id = id; 906 nctx->flags = flags; 907 nctx->len = nctx_len; 908 nctx->ctx_len = val_len; 909 memcpy(nctx->ctx, val, val_len); 910 911 if (copy_to_user(uctx, nctx, nctx_len)) 912 rc = -EFAULT; 913 914 out: 915 kfree(nctx); 916 *uctx_len = nctx_len; 917 return rc; 918 } 919 920 /* 921 * The default value of the LSM hook is defined in linux/lsm_hook_defs.h and 922 * can be accessed with: 923 * 924 * LSM_RET_DEFAULT(<hook_name>) 925 * 926 * The macros below define static constants for the default value of each 927 * LSM hook. 928 */ 929 #define LSM_RET_DEFAULT(NAME) (NAME##_default) 930 #define DECLARE_LSM_RET_DEFAULT_void(DEFAULT, NAME) 931 #define DECLARE_LSM_RET_DEFAULT_int(DEFAULT, NAME) \ 932 static const int __maybe_unused LSM_RET_DEFAULT(NAME) = (DEFAULT); 933 #define LSM_HOOK(RET, DEFAULT, NAME, ...) \ 934 DECLARE_LSM_RET_DEFAULT_##RET(DEFAULT, NAME) 935 936 #include <linux/lsm_hook_defs.h> 937 #undef LSM_HOOK 938 939 /* 940 * Hook list operation macros. 941 * 942 * call_void_hook: 943 * This is a hook that does not return a value. 944 * 945 * call_int_hook: 946 * This is a hook that returns a value. 947 */ 948 #define __CALL_STATIC_VOID(NUM, HOOK, ...) \ 949 do { \ 950 if (static_branch_unlikely(&SECURITY_HOOK_ACTIVE_KEY(HOOK, NUM))) { \ 951 static_call(LSM_STATIC_CALL(HOOK, NUM))(__VA_ARGS__); \ 952 } \ 953 } while (0); 954 955 #define call_void_hook(HOOK, ...) \ 956 do { \ 957 LSM_LOOP_UNROLL(__CALL_STATIC_VOID, HOOK, __VA_ARGS__); \ 958 } while (0) 959 960 961 #define __CALL_STATIC_INT(NUM, R, HOOK, LABEL, ...) \ 962 do { \ 963 if (static_branch_unlikely(&SECURITY_HOOK_ACTIVE_KEY(HOOK, NUM))) { \ 964 R = static_call(LSM_STATIC_CALL(HOOK, NUM))(__VA_ARGS__); \ 965 if (R != LSM_RET_DEFAULT(HOOK)) \ 966 goto LABEL; \ 967 } \ 968 } while (0); 969 970 #define call_int_hook(HOOK, ...) \ 971 ({ \ 972 __label__ OUT; \ 973 int RC = LSM_RET_DEFAULT(HOOK); \ 974 \ 975 LSM_LOOP_UNROLL(__CALL_STATIC_INT, RC, HOOK, OUT, __VA_ARGS__); \ 976 OUT: \ 977 RC; \ 978 }) 979 980 #define lsm_for_each_hook(scall, NAME) \ 981 for (scall = static_calls_table.NAME; \ 982 scall - static_calls_table.NAME < MAX_LSM_COUNT; scall++) \ 983 if (static_key_enabled(&scall->active->key)) 984 985 /* Security operations */ 986 987 /** 988 * security_binder_set_context_mgr() - Check if becoming binder ctx mgr is ok 989 * @mgr: task credentials of current binder process 990 * 991 * Check whether @mgr is allowed to be the binder context manager. 992 * 993 * Return: Return 0 if permission is granted. 994 */ 995 int security_binder_set_context_mgr(const struct cred *mgr) 996 { 997 return call_int_hook(binder_set_context_mgr, mgr); 998 } 999 1000 /** 1001 * security_binder_transaction() - Check if a binder transaction is allowed 1002 * @from: sending process 1003 * @to: receiving process 1004 * 1005 * Check whether @from is allowed to invoke a binder transaction call to @to. 1006 * 1007 * Return: Returns 0 if permission is granted. 1008 */ 1009 int security_binder_transaction(const struct cred *from, 1010 const struct cred *to) 1011 { 1012 return call_int_hook(binder_transaction, from, to); 1013 } 1014 1015 /** 1016 * security_binder_transfer_binder() - Check if a binder transfer is allowed 1017 * @from: sending process 1018 * @to: receiving process 1019 * 1020 * Check whether @from is allowed to transfer a binder reference to @to. 1021 * 1022 * Return: Returns 0 if permission is granted. 1023 */ 1024 int security_binder_transfer_binder(const struct cred *from, 1025 const struct cred *to) 1026 { 1027 return call_int_hook(binder_transfer_binder, from, to); 1028 } 1029 1030 /** 1031 * security_binder_transfer_file() - Check if a binder file xfer is allowed 1032 * @from: sending process 1033 * @to: receiving process 1034 * @file: file being transferred 1035 * 1036 * Check whether @from is allowed to transfer @file to @to. 1037 * 1038 * Return: Returns 0 if permission is granted. 1039 */ 1040 int security_binder_transfer_file(const struct cred *from, 1041 const struct cred *to, const struct file *file) 1042 { 1043 return call_int_hook(binder_transfer_file, from, to, file); 1044 } 1045 1046 /** 1047 * security_ptrace_access_check() - Check if tracing is allowed 1048 * @child: target process 1049 * @mode: PTRACE_MODE flags 1050 * 1051 * Check permission before allowing the current process to trace the @child 1052 * process. Security modules may also want to perform a process tracing check 1053 * during an execve in the set_security or apply_creds hooks of tracing check 1054 * during an execve in the bprm_set_creds hook of binprm_security_ops if the 1055 * process is being traced and its security attributes would be changed by the 1056 * execve. 1057 * 1058 * Return: Returns 0 if permission is granted. 1059 */ 1060 int security_ptrace_access_check(struct task_struct *child, unsigned int mode) 1061 { 1062 return call_int_hook(ptrace_access_check, child, mode); 1063 } 1064 1065 /** 1066 * security_ptrace_traceme() - Check if tracing is allowed 1067 * @parent: tracing process 1068 * 1069 * Check that the @parent process has sufficient permission to trace the 1070 * current process before allowing the current process to present itself to the 1071 * @parent process for tracing. 1072 * 1073 * Return: Returns 0 if permission is granted. 1074 */ 1075 int security_ptrace_traceme(struct task_struct *parent) 1076 { 1077 return call_int_hook(ptrace_traceme, parent); 1078 } 1079 1080 /** 1081 * security_capget() - Get the capability sets for a process 1082 * @target: target process 1083 * @effective: effective capability set 1084 * @inheritable: inheritable capability set 1085 * @permitted: permitted capability set 1086 * 1087 * Get the @effective, @inheritable, and @permitted capability sets for the 1088 * @target process. The hook may also perform permission checking to determine 1089 * if the current process is allowed to see the capability sets of the @target 1090 * process. 1091 * 1092 * Return: Returns 0 if the capability sets were successfully obtained. 1093 */ 1094 int security_capget(const struct task_struct *target, 1095 kernel_cap_t *effective, 1096 kernel_cap_t *inheritable, 1097 kernel_cap_t *permitted) 1098 { 1099 return call_int_hook(capget, target, effective, inheritable, permitted); 1100 } 1101 1102 /** 1103 * security_capset() - Set the capability sets for a process 1104 * @new: new credentials for the target process 1105 * @old: current credentials of the target process 1106 * @effective: effective capability set 1107 * @inheritable: inheritable capability set 1108 * @permitted: permitted capability set 1109 * 1110 * Set the @effective, @inheritable, and @permitted capability sets for the 1111 * current process. 1112 * 1113 * Return: Returns 0 and update @new if permission is granted. 1114 */ 1115 int security_capset(struct cred *new, const struct cred *old, 1116 const kernel_cap_t *effective, 1117 const kernel_cap_t *inheritable, 1118 const kernel_cap_t *permitted) 1119 { 1120 return call_int_hook(capset, new, old, effective, inheritable, 1121 permitted); 1122 } 1123 1124 /** 1125 * security_capable() - Check if a process has the necessary capability 1126 * @cred: credentials to examine 1127 * @ns: user namespace 1128 * @cap: capability requested 1129 * @opts: capability check options 1130 * 1131 * Check whether the @tsk process has the @cap capability in the indicated 1132 * credentials. @cap contains the capability <include/linux/capability.h>. 1133 * @opts contains options for the capable check <include/linux/security.h>. 1134 * 1135 * Return: Returns 0 if the capability is granted. 1136 */ 1137 int security_capable(const struct cred *cred, 1138 struct user_namespace *ns, 1139 int cap, 1140 unsigned int opts) 1141 { 1142 return call_int_hook(capable, cred, ns, cap, opts); 1143 } 1144 1145 /** 1146 * security_quotactl() - Check if a quotactl() syscall is allowed for this fs 1147 * @cmds: commands 1148 * @type: type 1149 * @id: id 1150 * @sb: filesystem 1151 * 1152 * Check whether the quotactl syscall is allowed for this @sb. 1153 * 1154 * Return: Returns 0 if permission is granted. 1155 */ 1156 int security_quotactl(int cmds, int type, int id, const struct super_block *sb) 1157 { 1158 return call_int_hook(quotactl, cmds, type, id, sb); 1159 } 1160 1161 /** 1162 * security_quota_on() - Check if QUOTAON is allowed for a dentry 1163 * @dentry: dentry 1164 * 1165 * Check whether QUOTAON is allowed for @dentry. 1166 * 1167 * Return: Returns 0 if permission is granted. 1168 */ 1169 int security_quota_on(struct dentry *dentry) 1170 { 1171 return call_int_hook(quota_on, dentry); 1172 } 1173 1174 /** 1175 * security_syslog() - Check if accessing the kernel message ring is allowed 1176 * @type: SYSLOG_ACTION_* type 1177 * 1178 * Check permission before accessing the kernel message ring or changing 1179 * logging to the console. See the syslog(2) manual page for an explanation of 1180 * the @type values. 1181 * 1182 * Return: Return 0 if permission is granted. 1183 */ 1184 int security_syslog(int type) 1185 { 1186 return call_int_hook(syslog, type); 1187 } 1188 1189 /** 1190 * security_settime64() - Check if changing the system time is allowed 1191 * @ts: new time 1192 * @tz: timezone 1193 * 1194 * Check permission to change the system time, struct timespec64 is defined in 1195 * <include/linux/time64.h> and timezone is defined in <include/linux/time.h>. 1196 * 1197 * Return: Returns 0 if permission is granted. 1198 */ 1199 int security_settime64(const struct timespec64 *ts, const struct timezone *tz) 1200 { 1201 return call_int_hook(settime, ts, tz); 1202 } 1203 1204 /** 1205 * security_vm_enough_memory_mm() - Check if allocating a new mem map is allowed 1206 * @mm: mm struct 1207 * @pages: number of pages 1208 * 1209 * Check permissions for allocating a new virtual mapping. If all LSMs return 1210 * a positive value, __vm_enough_memory() will be called with cap_sys_admin 1211 * set. If at least one LSM returns 0 or negative, __vm_enough_memory() will be 1212 * called with cap_sys_admin cleared. 1213 * 1214 * Return: Returns 0 if permission is granted by the LSM infrastructure to the 1215 * caller. 1216 */ 1217 int security_vm_enough_memory_mm(struct mm_struct *mm, long pages) 1218 { 1219 struct lsm_static_call *scall; 1220 int cap_sys_admin = 1; 1221 int rc; 1222 1223 /* 1224 * The module will respond with 0 if it thinks the __vm_enough_memory() 1225 * call should be made with the cap_sys_admin set. If all of the modules 1226 * agree that it should be set it will. If any module thinks it should 1227 * not be set it won't. 1228 */ 1229 lsm_for_each_hook(scall, vm_enough_memory) { 1230 rc = scall->hl->hook.vm_enough_memory(mm, pages); 1231 if (rc < 0) { 1232 cap_sys_admin = 0; 1233 break; 1234 } 1235 } 1236 return __vm_enough_memory(mm, pages, cap_sys_admin); 1237 } 1238 1239 /** 1240 * security_bprm_creds_for_exec() - Prepare the credentials for exec() 1241 * @bprm: binary program information 1242 * 1243 * If the setup in prepare_exec_creds did not setup @bprm->cred->security 1244 * properly for executing @bprm->file, update the LSM's portion of 1245 * @bprm->cred->security to be what commit_creds needs to install for the new 1246 * program. This hook may also optionally check permissions (e.g. for 1247 * transitions between security domains). The hook must set @bprm->secureexec 1248 * to 1 if AT_SECURE should be set to request libc enable secure mode. @bprm 1249 * contains the linux_binprm structure. 1250 * 1251 * Return: Returns 0 if the hook is successful and permission is granted. 1252 */ 1253 int security_bprm_creds_for_exec(struct linux_binprm *bprm) 1254 { 1255 return call_int_hook(bprm_creds_for_exec, bprm); 1256 } 1257 1258 /** 1259 * security_bprm_creds_from_file() - Update linux_binprm creds based on file 1260 * @bprm: binary program information 1261 * @file: associated file 1262 * 1263 * If @file is setpcap, suid, sgid or otherwise marked to change privilege upon 1264 * exec, update @bprm->cred to reflect that change. This is called after 1265 * finding the binary that will be executed without an interpreter. This 1266 * ensures that the credentials will not be derived from a script that the 1267 * binary will need to reopen, which when reopend may end up being a completely 1268 * different file. This hook may also optionally check permissions (e.g. for 1269 * transitions between security domains). The hook must set @bprm->secureexec 1270 * to 1 if AT_SECURE should be set to request libc enable secure mode. The 1271 * hook must add to @bprm->per_clear any personality flags that should be 1272 * cleared from current->personality. @bprm contains the linux_binprm 1273 * structure. 1274 * 1275 * Return: Returns 0 if the hook is successful and permission is granted. 1276 */ 1277 int security_bprm_creds_from_file(struct linux_binprm *bprm, const struct file *file) 1278 { 1279 return call_int_hook(bprm_creds_from_file, bprm, file); 1280 } 1281 1282 /** 1283 * security_bprm_check() - Mediate binary handler search 1284 * @bprm: binary program information 1285 * 1286 * This hook mediates the point when a search for a binary handler will begin. 1287 * It allows a check against the @bprm->cred->security value which was set in 1288 * the preceding creds_for_exec call. The argv list and envp list are reliably 1289 * available in @bprm. This hook may be called multiple times during a single 1290 * execve. @bprm contains the linux_binprm structure. 1291 * 1292 * Return: Returns 0 if the hook is successful and permission is granted. 1293 */ 1294 int security_bprm_check(struct linux_binprm *bprm) 1295 { 1296 return call_int_hook(bprm_check_security, bprm); 1297 } 1298 1299 /** 1300 * security_bprm_committing_creds() - Install creds for a process during exec() 1301 * @bprm: binary program information 1302 * 1303 * Prepare to install the new security attributes of a process being 1304 * transformed by an execve operation, based on the old credentials pointed to 1305 * by @current->cred and the information set in @bprm->cred by the 1306 * bprm_creds_for_exec hook. @bprm points to the linux_binprm structure. This 1307 * hook is a good place to perform state changes on the process such as closing 1308 * open file descriptors to which access will no longer be granted when the 1309 * attributes are changed. This is called immediately before commit_creds(). 1310 */ 1311 void security_bprm_committing_creds(const struct linux_binprm *bprm) 1312 { 1313 call_void_hook(bprm_committing_creds, bprm); 1314 } 1315 1316 /** 1317 * security_bprm_committed_creds() - Tidy up after cred install during exec() 1318 * @bprm: binary program information 1319 * 1320 * Tidy up after the installation of the new security attributes of a process 1321 * being transformed by an execve operation. The new credentials have, by this 1322 * point, been set to @current->cred. @bprm points to the linux_binprm 1323 * structure. This hook is a good place to perform state changes on the 1324 * process such as clearing out non-inheritable signal state. This is called 1325 * immediately after commit_creds(). 1326 */ 1327 void security_bprm_committed_creds(const struct linux_binprm *bprm) 1328 { 1329 call_void_hook(bprm_committed_creds, bprm); 1330 } 1331 1332 /** 1333 * security_fs_context_submount() - Initialise fc->security 1334 * @fc: new filesystem context 1335 * @reference: dentry reference for submount/remount 1336 * 1337 * Fill out the ->security field for a new fs_context. 1338 * 1339 * Return: Returns 0 on success or negative error code on failure. 1340 */ 1341 int security_fs_context_submount(struct fs_context *fc, struct super_block *reference) 1342 { 1343 return call_int_hook(fs_context_submount, fc, reference); 1344 } 1345 1346 /** 1347 * security_fs_context_dup() - Duplicate a fs_context LSM blob 1348 * @fc: destination filesystem context 1349 * @src_fc: source filesystem context 1350 * 1351 * Allocate and attach a security structure to sc->security. This pointer is 1352 * initialised to NULL by the caller. @fc indicates the new filesystem context. 1353 * @src_fc indicates the original filesystem context. 1354 * 1355 * Return: Returns 0 on success or a negative error code on failure. 1356 */ 1357 int security_fs_context_dup(struct fs_context *fc, struct fs_context *src_fc) 1358 { 1359 return call_int_hook(fs_context_dup, fc, src_fc); 1360 } 1361 1362 /** 1363 * security_fs_context_parse_param() - Configure a filesystem context 1364 * @fc: filesystem context 1365 * @param: filesystem parameter 1366 * 1367 * Userspace provided a parameter to configure a superblock. The LSM can 1368 * consume the parameter or return it to the caller for use elsewhere. 1369 * 1370 * Return: If the parameter is used by the LSM it should return 0, if it is 1371 * returned to the caller -ENOPARAM is returned, otherwise a negative 1372 * error code is returned. 1373 */ 1374 int security_fs_context_parse_param(struct fs_context *fc, 1375 struct fs_parameter *param) 1376 { 1377 struct lsm_static_call *scall; 1378 int trc; 1379 int rc = -ENOPARAM; 1380 1381 lsm_for_each_hook(scall, fs_context_parse_param) { 1382 trc = scall->hl->hook.fs_context_parse_param(fc, param); 1383 if (trc == 0) 1384 rc = 0; 1385 else if (trc != -ENOPARAM) 1386 return trc; 1387 } 1388 return rc; 1389 } 1390 1391 /** 1392 * security_sb_alloc() - Allocate a super_block LSM blob 1393 * @sb: filesystem superblock 1394 * 1395 * Allocate and attach a security structure to the sb->s_security field. The 1396 * s_security field is initialized to NULL when the structure is allocated. 1397 * @sb contains the super_block structure to be modified. 1398 * 1399 * Return: Returns 0 if operation was successful. 1400 */ 1401 int security_sb_alloc(struct super_block *sb) 1402 { 1403 int rc = lsm_superblock_alloc(sb); 1404 1405 if (unlikely(rc)) 1406 return rc; 1407 rc = call_int_hook(sb_alloc_security, sb); 1408 if (unlikely(rc)) 1409 security_sb_free(sb); 1410 return rc; 1411 } 1412 1413 /** 1414 * security_sb_delete() - Release super_block LSM associated objects 1415 * @sb: filesystem superblock 1416 * 1417 * Release objects tied to a superblock (e.g. inodes). @sb contains the 1418 * super_block structure being released. 1419 */ 1420 void security_sb_delete(struct super_block *sb) 1421 { 1422 call_void_hook(sb_delete, sb); 1423 } 1424 1425 /** 1426 * security_sb_free() - Free a super_block LSM blob 1427 * @sb: filesystem superblock 1428 * 1429 * Deallocate and clear the sb->s_security field. @sb contains the super_block 1430 * structure to be modified. 1431 */ 1432 void security_sb_free(struct super_block *sb) 1433 { 1434 call_void_hook(sb_free_security, sb); 1435 kfree(sb->s_security); 1436 sb->s_security = NULL; 1437 } 1438 1439 /** 1440 * security_free_mnt_opts() - Free memory associated with mount options 1441 * @mnt_opts: LSM processed mount options 1442 * 1443 * Free memory associated with @mnt_ops. 1444 */ 1445 void security_free_mnt_opts(void **mnt_opts) 1446 { 1447 if (!*mnt_opts) 1448 return; 1449 call_void_hook(sb_free_mnt_opts, *mnt_opts); 1450 *mnt_opts = NULL; 1451 } 1452 EXPORT_SYMBOL(security_free_mnt_opts); 1453 1454 /** 1455 * security_sb_eat_lsm_opts() - Consume LSM mount options 1456 * @options: mount options 1457 * @mnt_opts: LSM processed mount options 1458 * 1459 * Eat (scan @options) and save them in @mnt_opts. 1460 * 1461 * Return: Returns 0 on success, negative values on failure. 1462 */ 1463 int security_sb_eat_lsm_opts(char *options, void **mnt_opts) 1464 { 1465 return call_int_hook(sb_eat_lsm_opts, options, mnt_opts); 1466 } 1467 EXPORT_SYMBOL(security_sb_eat_lsm_opts); 1468 1469 /** 1470 * security_sb_mnt_opts_compat() - Check if new mount options are allowed 1471 * @sb: filesystem superblock 1472 * @mnt_opts: new mount options 1473 * 1474 * Determine if the new mount options in @mnt_opts are allowed given the 1475 * existing mounted filesystem at @sb. @sb superblock being compared. 1476 * 1477 * Return: Returns 0 if options are compatible. 1478 */ 1479 int security_sb_mnt_opts_compat(struct super_block *sb, 1480 void *mnt_opts) 1481 { 1482 return call_int_hook(sb_mnt_opts_compat, sb, mnt_opts); 1483 } 1484 EXPORT_SYMBOL(security_sb_mnt_opts_compat); 1485 1486 /** 1487 * security_sb_remount() - Verify no incompatible mount changes during remount 1488 * @sb: filesystem superblock 1489 * @mnt_opts: (re)mount options 1490 * 1491 * Extracts security system specific mount options and verifies no changes are 1492 * being made to those options. 1493 * 1494 * Return: Returns 0 if permission is granted. 1495 */ 1496 int security_sb_remount(struct super_block *sb, 1497 void *mnt_opts) 1498 { 1499 return call_int_hook(sb_remount, sb, mnt_opts); 1500 } 1501 EXPORT_SYMBOL(security_sb_remount); 1502 1503 /** 1504 * security_sb_kern_mount() - Check if a kernel mount is allowed 1505 * @sb: filesystem superblock 1506 * 1507 * Mount this @sb if allowed by permissions. 1508 * 1509 * Return: Returns 0 if permission is granted. 1510 */ 1511 int security_sb_kern_mount(const struct super_block *sb) 1512 { 1513 return call_int_hook(sb_kern_mount, sb); 1514 } 1515 1516 /** 1517 * security_sb_show_options() - Output the mount options for a superblock 1518 * @m: output file 1519 * @sb: filesystem superblock 1520 * 1521 * Show (print on @m) mount options for this @sb. 1522 * 1523 * Return: Returns 0 on success, negative values on failure. 1524 */ 1525 int security_sb_show_options(struct seq_file *m, struct super_block *sb) 1526 { 1527 return call_int_hook(sb_show_options, m, sb); 1528 } 1529 1530 /** 1531 * security_sb_statfs() - Check if accessing fs stats is allowed 1532 * @dentry: superblock handle 1533 * 1534 * Check permission before obtaining filesystem statistics for the @mnt 1535 * mountpoint. @dentry is a handle on the superblock for the filesystem. 1536 * 1537 * Return: Returns 0 if permission is granted. 1538 */ 1539 int security_sb_statfs(struct dentry *dentry) 1540 { 1541 return call_int_hook(sb_statfs, dentry); 1542 } 1543 1544 /** 1545 * security_sb_mount() - Check permission for mounting a filesystem 1546 * @dev_name: filesystem backing device 1547 * @path: mount point 1548 * @type: filesystem type 1549 * @flags: mount flags 1550 * @data: filesystem specific data 1551 * 1552 * Check permission before an object specified by @dev_name is mounted on the 1553 * mount point named by @nd. For an ordinary mount, @dev_name identifies a 1554 * device if the file system type requires a device. For a remount 1555 * (@flags & MS_REMOUNT), @dev_name is irrelevant. For a loopback/bind mount 1556 * (@flags & MS_BIND), @dev_name identifies the pathname of the object being 1557 * mounted. 1558 * 1559 * Return: Returns 0 if permission is granted. 1560 */ 1561 int security_sb_mount(const char *dev_name, const struct path *path, 1562 const char *type, unsigned long flags, void *data) 1563 { 1564 return call_int_hook(sb_mount, dev_name, path, type, flags, data); 1565 } 1566 1567 /** 1568 * security_sb_umount() - Check permission for unmounting a filesystem 1569 * @mnt: mounted filesystem 1570 * @flags: unmount flags 1571 * 1572 * Check permission before the @mnt file system is unmounted. 1573 * 1574 * Return: Returns 0 if permission is granted. 1575 */ 1576 int security_sb_umount(struct vfsmount *mnt, int flags) 1577 { 1578 return call_int_hook(sb_umount, mnt, flags); 1579 } 1580 1581 /** 1582 * security_sb_pivotroot() - Check permissions for pivoting the rootfs 1583 * @old_path: new location for current rootfs 1584 * @new_path: location of the new rootfs 1585 * 1586 * Check permission before pivoting the root filesystem. 1587 * 1588 * Return: Returns 0 if permission is granted. 1589 */ 1590 int security_sb_pivotroot(const struct path *old_path, 1591 const struct path *new_path) 1592 { 1593 return call_int_hook(sb_pivotroot, old_path, new_path); 1594 } 1595 1596 /** 1597 * security_sb_set_mnt_opts() - Set the mount options for a filesystem 1598 * @sb: filesystem superblock 1599 * @mnt_opts: binary mount options 1600 * @kern_flags: kernel flags (in) 1601 * @set_kern_flags: kernel flags (out) 1602 * 1603 * Set the security relevant mount options used for a superblock. 1604 * 1605 * Return: Returns 0 on success, error on failure. 1606 */ 1607 int security_sb_set_mnt_opts(struct super_block *sb, 1608 void *mnt_opts, 1609 unsigned long kern_flags, 1610 unsigned long *set_kern_flags) 1611 { 1612 struct lsm_static_call *scall; 1613 int rc = mnt_opts ? -EOPNOTSUPP : LSM_RET_DEFAULT(sb_set_mnt_opts); 1614 1615 lsm_for_each_hook(scall, sb_set_mnt_opts) { 1616 rc = scall->hl->hook.sb_set_mnt_opts(sb, mnt_opts, kern_flags, 1617 set_kern_flags); 1618 if (rc != LSM_RET_DEFAULT(sb_set_mnt_opts)) 1619 break; 1620 } 1621 return rc; 1622 } 1623 EXPORT_SYMBOL(security_sb_set_mnt_opts); 1624 1625 /** 1626 * security_sb_clone_mnt_opts() - Duplicate superblock mount options 1627 * @oldsb: source superblock 1628 * @newsb: destination superblock 1629 * @kern_flags: kernel flags (in) 1630 * @set_kern_flags: kernel flags (out) 1631 * 1632 * Copy all security options from a given superblock to another. 1633 * 1634 * Return: Returns 0 on success, error on failure. 1635 */ 1636 int security_sb_clone_mnt_opts(const struct super_block *oldsb, 1637 struct super_block *newsb, 1638 unsigned long kern_flags, 1639 unsigned long *set_kern_flags) 1640 { 1641 return call_int_hook(sb_clone_mnt_opts, oldsb, newsb, 1642 kern_flags, set_kern_flags); 1643 } 1644 EXPORT_SYMBOL(security_sb_clone_mnt_opts); 1645 1646 /** 1647 * security_move_mount() - Check permissions for moving a mount 1648 * @from_path: source mount point 1649 * @to_path: destination mount point 1650 * 1651 * Check permission before a mount is moved. 1652 * 1653 * Return: Returns 0 if permission is granted. 1654 */ 1655 int security_move_mount(const struct path *from_path, 1656 const struct path *to_path) 1657 { 1658 return call_int_hook(move_mount, from_path, to_path); 1659 } 1660 1661 /** 1662 * security_path_notify() - Check if setting a watch is allowed 1663 * @path: file path 1664 * @mask: event mask 1665 * @obj_type: file path type 1666 * 1667 * Check permissions before setting a watch on events as defined by @mask, on 1668 * an object at @path, whose type is defined by @obj_type. 1669 * 1670 * Return: Returns 0 if permission is granted. 1671 */ 1672 int security_path_notify(const struct path *path, u64 mask, 1673 unsigned int obj_type) 1674 { 1675 return call_int_hook(path_notify, path, mask, obj_type); 1676 } 1677 1678 /** 1679 * security_inode_alloc() - Allocate an inode LSM blob 1680 * @inode: the inode 1681 * @gfp: allocation flags 1682 * 1683 * Allocate and attach a security structure to @inode->i_security. The 1684 * i_security field is initialized to NULL when the inode structure is 1685 * allocated. 1686 * 1687 * Return: Return 0 if operation was successful. 1688 */ 1689 int security_inode_alloc(struct inode *inode, gfp_t gfp) 1690 { 1691 int rc = lsm_inode_alloc(inode, gfp); 1692 1693 if (unlikely(rc)) 1694 return rc; 1695 rc = call_int_hook(inode_alloc_security, inode); 1696 if (unlikely(rc)) 1697 security_inode_free(inode); 1698 return rc; 1699 } 1700 1701 static void inode_free_by_rcu(struct rcu_head *head) 1702 { 1703 /* The rcu head is at the start of the inode blob */ 1704 call_void_hook(inode_free_security_rcu, head); 1705 kmem_cache_free(lsm_inode_cache, head); 1706 } 1707 1708 /** 1709 * security_inode_free() - Free an inode's LSM blob 1710 * @inode: the inode 1711 * 1712 * Release any LSM resources associated with @inode, although due to the 1713 * inode's RCU protections it is possible that the resources will not be 1714 * fully released until after the current RCU grace period has elapsed. 1715 * 1716 * It is important for LSMs to note that despite being present in a call to 1717 * security_inode_free(), @inode may still be referenced in a VFS path walk 1718 * and calls to security_inode_permission() may be made during, or after, 1719 * a call to security_inode_free(). For this reason the inode->i_security 1720 * field is released via a call_rcu() callback and any LSMs which need to 1721 * retain inode state for use in security_inode_permission() should only 1722 * release that state in the inode_free_security_rcu() LSM hook callback. 1723 */ 1724 void security_inode_free(struct inode *inode) 1725 { 1726 call_void_hook(inode_free_security, inode); 1727 if (!inode->i_security) 1728 return; 1729 call_rcu((struct rcu_head *)inode->i_security, inode_free_by_rcu); 1730 } 1731 1732 /** 1733 * security_dentry_init_security() - Perform dentry initialization 1734 * @dentry: the dentry to initialize 1735 * @mode: mode used to determine resource type 1736 * @name: name of the last path component 1737 * @xattr_name: name of the security/LSM xattr 1738 * @ctx: pointer to the resulting LSM context 1739 * @ctxlen: length of @ctx 1740 * 1741 * Compute a context for a dentry as the inode is not yet available since NFSv4 1742 * has no label backed by an EA anyway. It is important to note that 1743 * @xattr_name does not need to be free'd by the caller, it is a static string. 1744 * 1745 * Return: Returns 0 on success, negative values on failure. 1746 */ 1747 int security_dentry_init_security(struct dentry *dentry, int mode, 1748 const struct qstr *name, 1749 const char **xattr_name, void **ctx, 1750 u32 *ctxlen) 1751 { 1752 return call_int_hook(dentry_init_security, dentry, mode, name, 1753 xattr_name, ctx, ctxlen); 1754 } 1755 EXPORT_SYMBOL(security_dentry_init_security); 1756 1757 /** 1758 * security_dentry_create_files_as() - Perform dentry initialization 1759 * @dentry: the dentry to initialize 1760 * @mode: mode used to determine resource type 1761 * @name: name of the last path component 1762 * @old: creds to use for LSM context calculations 1763 * @new: creds to modify 1764 * 1765 * Compute a context for a dentry as the inode is not yet available and set 1766 * that context in passed in creds so that new files are created using that 1767 * context. Context is calculated using the passed in creds and not the creds 1768 * of the caller. 1769 * 1770 * Return: Returns 0 on success, error on failure. 1771 */ 1772 int security_dentry_create_files_as(struct dentry *dentry, int mode, 1773 struct qstr *name, 1774 const struct cred *old, struct cred *new) 1775 { 1776 return call_int_hook(dentry_create_files_as, dentry, mode, 1777 name, old, new); 1778 } 1779 EXPORT_SYMBOL(security_dentry_create_files_as); 1780 1781 /** 1782 * security_inode_init_security() - Initialize an inode's LSM context 1783 * @inode: the inode 1784 * @dir: parent directory 1785 * @qstr: last component of the pathname 1786 * @initxattrs: callback function to write xattrs 1787 * @fs_data: filesystem specific data 1788 * 1789 * Obtain the security attribute name suffix and value to set on a newly 1790 * created inode and set up the incore security field for the new inode. This 1791 * hook is called by the fs code as part of the inode creation transaction and 1792 * provides for atomic labeling of the inode, unlike the post_create/mkdir/... 1793 * hooks called by the VFS. 1794 * 1795 * The hook function is expected to populate the xattrs array, by calling 1796 * lsm_get_xattr_slot() to retrieve the slots reserved by the security module 1797 * with the lbs_xattr_count field of the lsm_blob_sizes structure. For each 1798 * slot, the hook function should set ->name to the attribute name suffix 1799 * (e.g. selinux), to allocate ->value (will be freed by the caller) and set it 1800 * to the attribute value, to set ->value_len to the length of the value. If 1801 * the security module does not use security attributes or does not wish to put 1802 * a security attribute on this particular inode, then it should return 1803 * -EOPNOTSUPP to skip this processing. 1804 * 1805 * Return: Returns 0 if the LSM successfully initialized all of the inode 1806 * security attributes that are required, negative values otherwise. 1807 */ 1808 int security_inode_init_security(struct inode *inode, struct inode *dir, 1809 const struct qstr *qstr, 1810 const initxattrs initxattrs, void *fs_data) 1811 { 1812 struct lsm_static_call *scall; 1813 struct xattr *new_xattrs = NULL; 1814 int ret = -EOPNOTSUPP, xattr_count = 0; 1815 1816 if (unlikely(IS_PRIVATE(inode))) 1817 return 0; 1818 1819 if (!blob_sizes.lbs_xattr_count) 1820 return 0; 1821 1822 if (initxattrs) { 1823 /* Allocate +1 as terminator. */ 1824 new_xattrs = kcalloc(blob_sizes.lbs_xattr_count + 1, 1825 sizeof(*new_xattrs), GFP_NOFS); 1826 if (!new_xattrs) 1827 return -ENOMEM; 1828 } 1829 1830 lsm_for_each_hook(scall, inode_init_security) { 1831 ret = scall->hl->hook.inode_init_security(inode, dir, qstr, new_xattrs, 1832 &xattr_count); 1833 if (ret && ret != -EOPNOTSUPP) 1834 goto out; 1835 /* 1836 * As documented in lsm_hooks.h, -EOPNOTSUPP in this context 1837 * means that the LSM is not willing to provide an xattr, not 1838 * that it wants to signal an error. Thus, continue to invoke 1839 * the remaining LSMs. 1840 */ 1841 } 1842 1843 /* If initxattrs() is NULL, xattr_count is zero, skip the call. */ 1844 if (!xattr_count) 1845 goto out; 1846 1847 ret = initxattrs(inode, new_xattrs, fs_data); 1848 out: 1849 for (; xattr_count > 0; xattr_count--) 1850 kfree(new_xattrs[xattr_count - 1].value); 1851 kfree(new_xattrs); 1852 return (ret == -EOPNOTSUPP) ? 0 : ret; 1853 } 1854 EXPORT_SYMBOL(security_inode_init_security); 1855 1856 /** 1857 * security_inode_init_security_anon() - Initialize an anonymous inode 1858 * @inode: the inode 1859 * @name: the anonymous inode class 1860 * @context_inode: an optional related inode 1861 * 1862 * Set up the incore security field for the new anonymous inode and return 1863 * whether the inode creation is permitted by the security module or not. 1864 * 1865 * Return: Returns 0 on success, -EACCES if the security module denies the 1866 * creation of this inode, or another -errno upon other errors. 1867 */ 1868 int security_inode_init_security_anon(struct inode *inode, 1869 const struct qstr *name, 1870 const struct inode *context_inode) 1871 { 1872 return call_int_hook(inode_init_security_anon, inode, name, 1873 context_inode); 1874 } 1875 1876 #ifdef CONFIG_SECURITY_PATH 1877 /** 1878 * security_path_mknod() - Check if creating a special file is allowed 1879 * @dir: parent directory 1880 * @dentry: new file 1881 * @mode: new file mode 1882 * @dev: device number 1883 * 1884 * Check permissions when creating a file. Note that this hook is called even 1885 * if mknod operation is being done for a regular file. 1886 * 1887 * Return: Returns 0 if permission is granted. 1888 */ 1889 int security_path_mknod(const struct path *dir, struct dentry *dentry, 1890 umode_t mode, unsigned int dev) 1891 { 1892 if (unlikely(IS_PRIVATE(d_backing_inode(dir->dentry)))) 1893 return 0; 1894 return call_int_hook(path_mknod, dir, dentry, mode, dev); 1895 } 1896 EXPORT_SYMBOL(security_path_mknod); 1897 1898 /** 1899 * security_path_post_mknod() - Update inode security after reg file creation 1900 * @idmap: idmap of the mount 1901 * @dentry: new file 1902 * 1903 * Update inode security field after a regular file has been created. 1904 */ 1905 void security_path_post_mknod(struct mnt_idmap *idmap, struct dentry *dentry) 1906 { 1907 if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) 1908 return; 1909 call_void_hook(path_post_mknod, idmap, dentry); 1910 } 1911 1912 /** 1913 * security_path_mkdir() - Check if creating a new directory is allowed 1914 * @dir: parent directory 1915 * @dentry: new directory 1916 * @mode: new directory mode 1917 * 1918 * Check permissions to create a new directory in the existing directory. 1919 * 1920 * Return: Returns 0 if permission is granted. 1921 */ 1922 int security_path_mkdir(const struct path *dir, struct dentry *dentry, 1923 umode_t mode) 1924 { 1925 if (unlikely(IS_PRIVATE(d_backing_inode(dir->dentry)))) 1926 return 0; 1927 return call_int_hook(path_mkdir, dir, dentry, mode); 1928 } 1929 EXPORT_SYMBOL(security_path_mkdir); 1930 1931 /** 1932 * security_path_rmdir() - Check if removing a directory is allowed 1933 * @dir: parent directory 1934 * @dentry: directory to remove 1935 * 1936 * Check the permission to remove a directory. 1937 * 1938 * Return: Returns 0 if permission is granted. 1939 */ 1940 int security_path_rmdir(const struct path *dir, struct dentry *dentry) 1941 { 1942 if (unlikely(IS_PRIVATE(d_backing_inode(dir->dentry)))) 1943 return 0; 1944 return call_int_hook(path_rmdir, dir, dentry); 1945 } 1946 1947 /** 1948 * security_path_unlink() - Check if removing a hard link is allowed 1949 * @dir: parent directory 1950 * @dentry: file 1951 * 1952 * Check the permission to remove a hard link to a file. 1953 * 1954 * Return: Returns 0 if permission is granted. 1955 */ 1956 int security_path_unlink(const struct path *dir, struct dentry *dentry) 1957 { 1958 if (unlikely(IS_PRIVATE(d_backing_inode(dir->dentry)))) 1959 return 0; 1960 return call_int_hook(path_unlink, dir, dentry); 1961 } 1962 EXPORT_SYMBOL(security_path_unlink); 1963 1964 /** 1965 * security_path_symlink() - Check if creating a symbolic link is allowed 1966 * @dir: parent directory 1967 * @dentry: symbolic link 1968 * @old_name: file pathname 1969 * 1970 * Check the permission to create a symbolic link to a file. 1971 * 1972 * Return: Returns 0 if permission is granted. 1973 */ 1974 int security_path_symlink(const struct path *dir, struct dentry *dentry, 1975 const char *old_name) 1976 { 1977 if (unlikely(IS_PRIVATE(d_backing_inode(dir->dentry)))) 1978 return 0; 1979 return call_int_hook(path_symlink, dir, dentry, old_name); 1980 } 1981 1982 /** 1983 * security_path_link - Check if creating a hard link is allowed 1984 * @old_dentry: existing file 1985 * @new_dir: new parent directory 1986 * @new_dentry: new link 1987 * 1988 * Check permission before creating a new hard link to a file. 1989 * 1990 * Return: Returns 0 if permission is granted. 1991 */ 1992 int security_path_link(struct dentry *old_dentry, const struct path *new_dir, 1993 struct dentry *new_dentry) 1994 { 1995 if (unlikely(IS_PRIVATE(d_backing_inode(old_dentry)))) 1996 return 0; 1997 return call_int_hook(path_link, old_dentry, new_dir, new_dentry); 1998 } 1999 2000 /** 2001 * security_path_rename() - Check if renaming a file is allowed 2002 * @old_dir: parent directory of the old file 2003 * @old_dentry: the old file 2004 * @new_dir: parent directory of the new file 2005 * @new_dentry: the new file 2006 * @flags: flags 2007 * 2008 * Check for permission to rename a file or directory. 2009 * 2010 * Return: Returns 0 if permission is granted. 2011 */ 2012 int security_path_rename(const struct path *old_dir, struct dentry *old_dentry, 2013 const struct path *new_dir, struct dentry *new_dentry, 2014 unsigned int flags) 2015 { 2016 if (unlikely(IS_PRIVATE(d_backing_inode(old_dentry)) || 2017 (d_is_positive(new_dentry) && 2018 IS_PRIVATE(d_backing_inode(new_dentry))))) 2019 return 0; 2020 2021 return call_int_hook(path_rename, old_dir, old_dentry, new_dir, 2022 new_dentry, flags); 2023 } 2024 EXPORT_SYMBOL(security_path_rename); 2025 2026 /** 2027 * security_path_truncate() - Check if truncating a file is allowed 2028 * @path: file 2029 * 2030 * Check permission before truncating the file indicated by path. Note that 2031 * truncation permissions may also be checked based on already opened files, 2032 * using the security_file_truncate() hook. 2033 * 2034 * Return: Returns 0 if permission is granted. 2035 */ 2036 int security_path_truncate(const struct path *path) 2037 { 2038 if (unlikely(IS_PRIVATE(d_backing_inode(path->dentry)))) 2039 return 0; 2040 return call_int_hook(path_truncate, path); 2041 } 2042 2043 /** 2044 * security_path_chmod() - Check if changing the file's mode is allowed 2045 * @path: file 2046 * @mode: new mode 2047 * 2048 * Check for permission to change a mode of the file @path. The new mode is 2049 * specified in @mode which is a bitmask of constants from 2050 * <include/uapi/linux/stat.h>. 2051 * 2052 * Return: Returns 0 if permission is granted. 2053 */ 2054 int security_path_chmod(const struct path *path, umode_t mode) 2055 { 2056 if (unlikely(IS_PRIVATE(d_backing_inode(path->dentry)))) 2057 return 0; 2058 return call_int_hook(path_chmod, path, mode); 2059 } 2060 2061 /** 2062 * security_path_chown() - Check if changing the file's owner/group is allowed 2063 * @path: file 2064 * @uid: file owner 2065 * @gid: file group 2066 * 2067 * Check for permission to change owner/group of a file or directory. 2068 * 2069 * Return: Returns 0 if permission is granted. 2070 */ 2071 int security_path_chown(const struct path *path, kuid_t uid, kgid_t gid) 2072 { 2073 if (unlikely(IS_PRIVATE(d_backing_inode(path->dentry)))) 2074 return 0; 2075 return call_int_hook(path_chown, path, uid, gid); 2076 } 2077 2078 /** 2079 * security_path_chroot() - Check if changing the root directory is allowed 2080 * @path: directory 2081 * 2082 * Check for permission to change root directory. 2083 * 2084 * Return: Returns 0 if permission is granted. 2085 */ 2086 int security_path_chroot(const struct path *path) 2087 { 2088 return call_int_hook(path_chroot, path); 2089 } 2090 #endif /* CONFIG_SECURITY_PATH */ 2091 2092 /** 2093 * security_inode_create() - Check if creating a file is allowed 2094 * @dir: the parent directory 2095 * @dentry: the file being created 2096 * @mode: requested file mode 2097 * 2098 * Check permission to create a regular file. 2099 * 2100 * Return: Returns 0 if permission is granted. 2101 */ 2102 int security_inode_create(struct inode *dir, struct dentry *dentry, 2103 umode_t mode) 2104 { 2105 if (unlikely(IS_PRIVATE(dir))) 2106 return 0; 2107 return call_int_hook(inode_create, dir, dentry, mode); 2108 } 2109 EXPORT_SYMBOL_GPL(security_inode_create); 2110 2111 /** 2112 * security_inode_post_create_tmpfile() - Update inode security of new tmpfile 2113 * @idmap: idmap of the mount 2114 * @inode: inode of the new tmpfile 2115 * 2116 * Update inode security data after a tmpfile has been created. 2117 */ 2118 void security_inode_post_create_tmpfile(struct mnt_idmap *idmap, 2119 struct inode *inode) 2120 { 2121 if (unlikely(IS_PRIVATE(inode))) 2122 return; 2123 call_void_hook(inode_post_create_tmpfile, idmap, inode); 2124 } 2125 2126 /** 2127 * security_inode_link() - Check if creating a hard link is allowed 2128 * @old_dentry: existing file 2129 * @dir: new parent directory 2130 * @new_dentry: new link 2131 * 2132 * Check permission before creating a new hard link to a file. 2133 * 2134 * Return: Returns 0 if permission is granted. 2135 */ 2136 int security_inode_link(struct dentry *old_dentry, struct inode *dir, 2137 struct dentry *new_dentry) 2138 { 2139 if (unlikely(IS_PRIVATE(d_backing_inode(old_dentry)))) 2140 return 0; 2141 return call_int_hook(inode_link, old_dentry, dir, new_dentry); 2142 } 2143 2144 /** 2145 * security_inode_unlink() - Check if removing a hard link is allowed 2146 * @dir: parent directory 2147 * @dentry: file 2148 * 2149 * Check the permission to remove a hard link to a file. 2150 * 2151 * Return: Returns 0 if permission is granted. 2152 */ 2153 int security_inode_unlink(struct inode *dir, struct dentry *dentry) 2154 { 2155 if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) 2156 return 0; 2157 return call_int_hook(inode_unlink, dir, dentry); 2158 } 2159 2160 /** 2161 * security_inode_symlink() - Check if creating a symbolic link is allowed 2162 * @dir: parent directory 2163 * @dentry: symbolic link 2164 * @old_name: existing filename 2165 * 2166 * Check the permission to create a symbolic link to a file. 2167 * 2168 * Return: Returns 0 if permission is granted. 2169 */ 2170 int security_inode_symlink(struct inode *dir, struct dentry *dentry, 2171 const char *old_name) 2172 { 2173 if (unlikely(IS_PRIVATE(dir))) 2174 return 0; 2175 return call_int_hook(inode_symlink, dir, dentry, old_name); 2176 } 2177 2178 /** 2179 * security_inode_mkdir() - Check if creation a new director is allowed 2180 * @dir: parent directory 2181 * @dentry: new directory 2182 * @mode: new directory mode 2183 * 2184 * Check permissions to create a new directory in the existing directory 2185 * associated with inode structure @dir. 2186 * 2187 * Return: Returns 0 if permission is granted. 2188 */ 2189 int security_inode_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode) 2190 { 2191 if (unlikely(IS_PRIVATE(dir))) 2192 return 0; 2193 return call_int_hook(inode_mkdir, dir, dentry, mode); 2194 } 2195 EXPORT_SYMBOL_GPL(security_inode_mkdir); 2196 2197 /** 2198 * security_inode_rmdir() - Check if removing a directory is allowed 2199 * @dir: parent directory 2200 * @dentry: directory to be removed 2201 * 2202 * Check the permission to remove a directory. 2203 * 2204 * Return: Returns 0 if permission is granted. 2205 */ 2206 int security_inode_rmdir(struct inode *dir, struct dentry *dentry) 2207 { 2208 if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) 2209 return 0; 2210 return call_int_hook(inode_rmdir, dir, dentry); 2211 } 2212 2213 /** 2214 * security_inode_mknod() - Check if creating a special file is allowed 2215 * @dir: parent directory 2216 * @dentry: new file 2217 * @mode: new file mode 2218 * @dev: device number 2219 * 2220 * Check permissions when creating a special file (or a socket or a fifo file 2221 * created via the mknod system call). Note that if mknod operation is being 2222 * done for a regular file, then the create hook will be called and not this 2223 * hook. 2224 * 2225 * Return: Returns 0 if permission is granted. 2226 */ 2227 int security_inode_mknod(struct inode *dir, struct dentry *dentry, 2228 umode_t mode, dev_t dev) 2229 { 2230 if (unlikely(IS_PRIVATE(dir))) 2231 return 0; 2232 return call_int_hook(inode_mknod, dir, dentry, mode, dev); 2233 } 2234 2235 /** 2236 * security_inode_rename() - Check if renaming a file is allowed 2237 * @old_dir: parent directory of the old file 2238 * @old_dentry: the old file 2239 * @new_dir: parent directory of the new file 2240 * @new_dentry: the new file 2241 * @flags: flags 2242 * 2243 * Check for permission to rename a file or directory. 2244 * 2245 * Return: Returns 0 if permission is granted. 2246 */ 2247 int security_inode_rename(struct inode *old_dir, struct dentry *old_dentry, 2248 struct inode *new_dir, struct dentry *new_dentry, 2249 unsigned int flags) 2250 { 2251 if (unlikely(IS_PRIVATE(d_backing_inode(old_dentry)) || 2252 (d_is_positive(new_dentry) && 2253 IS_PRIVATE(d_backing_inode(new_dentry))))) 2254 return 0; 2255 2256 if (flags & RENAME_EXCHANGE) { 2257 int err = call_int_hook(inode_rename, new_dir, new_dentry, 2258 old_dir, old_dentry); 2259 if (err) 2260 return err; 2261 } 2262 2263 return call_int_hook(inode_rename, old_dir, old_dentry, 2264 new_dir, new_dentry); 2265 } 2266 2267 /** 2268 * security_inode_readlink() - Check if reading a symbolic link is allowed 2269 * @dentry: link 2270 * 2271 * Check the permission to read the symbolic link. 2272 * 2273 * Return: Returns 0 if permission is granted. 2274 */ 2275 int security_inode_readlink(struct dentry *dentry) 2276 { 2277 if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) 2278 return 0; 2279 return call_int_hook(inode_readlink, dentry); 2280 } 2281 2282 /** 2283 * security_inode_follow_link() - Check if following a symbolic link is allowed 2284 * @dentry: link dentry 2285 * @inode: link inode 2286 * @rcu: true if in RCU-walk mode 2287 * 2288 * Check permission to follow a symbolic link when looking up a pathname. If 2289 * @rcu is true, @inode is not stable. 2290 * 2291 * Return: Returns 0 if permission is granted. 2292 */ 2293 int security_inode_follow_link(struct dentry *dentry, struct inode *inode, 2294 bool rcu) 2295 { 2296 if (unlikely(IS_PRIVATE(inode))) 2297 return 0; 2298 return call_int_hook(inode_follow_link, dentry, inode, rcu); 2299 } 2300 2301 /** 2302 * security_inode_permission() - Check if accessing an inode is allowed 2303 * @inode: inode 2304 * @mask: access mask 2305 * 2306 * Check permission before accessing an inode. This hook is called by the 2307 * existing Linux permission function, so a security module can use it to 2308 * provide additional checking for existing Linux permission checks. Notice 2309 * that this hook is called when a file is opened (as well as many other 2310 * operations), whereas the file_security_ops permission hook is called when 2311 * the actual read/write operations are performed. 2312 * 2313 * Return: Returns 0 if permission is granted. 2314 */ 2315 int security_inode_permission(struct inode *inode, int mask) 2316 { 2317 if (unlikely(IS_PRIVATE(inode))) 2318 return 0; 2319 return call_int_hook(inode_permission, inode, mask); 2320 } 2321 2322 /** 2323 * security_inode_setattr() - Check if setting file attributes is allowed 2324 * @idmap: idmap of the mount 2325 * @dentry: file 2326 * @attr: new attributes 2327 * 2328 * Check permission before setting file attributes. Note that the kernel call 2329 * to notify_change is performed from several locations, whenever file 2330 * attributes change (such as when a file is truncated, chown/chmod operations, 2331 * transferring disk quotas, etc). 2332 * 2333 * Return: Returns 0 if permission is granted. 2334 */ 2335 int security_inode_setattr(struct mnt_idmap *idmap, 2336 struct dentry *dentry, struct iattr *attr) 2337 { 2338 if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) 2339 return 0; 2340 return call_int_hook(inode_setattr, idmap, dentry, attr); 2341 } 2342 EXPORT_SYMBOL_GPL(security_inode_setattr); 2343 2344 /** 2345 * security_inode_post_setattr() - Update the inode after a setattr operation 2346 * @idmap: idmap of the mount 2347 * @dentry: file 2348 * @ia_valid: file attributes set 2349 * 2350 * Update inode security field after successful setting file attributes. 2351 */ 2352 void security_inode_post_setattr(struct mnt_idmap *idmap, struct dentry *dentry, 2353 int ia_valid) 2354 { 2355 if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) 2356 return; 2357 call_void_hook(inode_post_setattr, idmap, dentry, ia_valid); 2358 } 2359 2360 /** 2361 * security_inode_getattr() - Check if getting file attributes is allowed 2362 * @path: file 2363 * 2364 * Check permission before obtaining file attributes. 2365 * 2366 * Return: Returns 0 if permission is granted. 2367 */ 2368 int security_inode_getattr(const struct path *path) 2369 { 2370 if (unlikely(IS_PRIVATE(d_backing_inode(path->dentry)))) 2371 return 0; 2372 return call_int_hook(inode_getattr, path); 2373 } 2374 2375 /** 2376 * security_inode_setxattr() - Check if setting file xattrs is allowed 2377 * @idmap: idmap of the mount 2378 * @dentry: file 2379 * @name: xattr name 2380 * @value: xattr value 2381 * @size: size of xattr value 2382 * @flags: flags 2383 * 2384 * This hook performs the desired permission checks before setting the extended 2385 * attributes (xattrs) on @dentry. It is important to note that we have some 2386 * additional logic before the main LSM implementation calls to detect if we 2387 * need to perform an additional capability check at the LSM layer. 2388 * 2389 * Normally we enforce a capability check prior to executing the various LSM 2390 * hook implementations, but if a LSM wants to avoid this capability check, 2391 * it can register a 'inode_xattr_skipcap' hook and return a value of 1 for 2392 * xattrs that it wants to avoid the capability check, leaving the LSM fully 2393 * responsible for enforcing the access control for the specific xattr. If all 2394 * of the enabled LSMs refrain from registering a 'inode_xattr_skipcap' hook, 2395 * or return a 0 (the default return value), the capability check is still 2396 * performed. If no 'inode_xattr_skipcap' hooks are registered the capability 2397 * check is performed. 2398 * 2399 * Return: Returns 0 if permission is granted. 2400 */ 2401 int security_inode_setxattr(struct mnt_idmap *idmap, 2402 struct dentry *dentry, const char *name, 2403 const void *value, size_t size, int flags) 2404 { 2405 int rc; 2406 2407 if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) 2408 return 0; 2409 2410 /* enforce the capability checks at the lsm layer, if needed */ 2411 if (!call_int_hook(inode_xattr_skipcap, name)) { 2412 rc = cap_inode_setxattr(dentry, name, value, size, flags); 2413 if (rc) 2414 return rc; 2415 } 2416 2417 return call_int_hook(inode_setxattr, idmap, dentry, name, value, size, 2418 flags); 2419 } 2420 2421 /** 2422 * security_inode_set_acl() - Check if setting posix acls is allowed 2423 * @idmap: idmap of the mount 2424 * @dentry: file 2425 * @acl_name: acl name 2426 * @kacl: acl struct 2427 * 2428 * Check permission before setting posix acls, the posix acls in @kacl are 2429 * identified by @acl_name. 2430 * 2431 * Return: Returns 0 if permission is granted. 2432 */ 2433 int security_inode_set_acl(struct mnt_idmap *idmap, 2434 struct dentry *dentry, const char *acl_name, 2435 struct posix_acl *kacl) 2436 { 2437 if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) 2438 return 0; 2439 return call_int_hook(inode_set_acl, idmap, dentry, acl_name, kacl); 2440 } 2441 2442 /** 2443 * security_inode_post_set_acl() - Update inode security from posix acls set 2444 * @dentry: file 2445 * @acl_name: acl name 2446 * @kacl: acl struct 2447 * 2448 * Update inode security data after successfully setting posix acls on @dentry. 2449 * The posix acls in @kacl are identified by @acl_name. 2450 */ 2451 void security_inode_post_set_acl(struct dentry *dentry, const char *acl_name, 2452 struct posix_acl *kacl) 2453 { 2454 if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) 2455 return; 2456 call_void_hook(inode_post_set_acl, dentry, acl_name, kacl); 2457 } 2458 2459 /** 2460 * security_inode_get_acl() - Check if reading posix acls is allowed 2461 * @idmap: idmap of the mount 2462 * @dentry: file 2463 * @acl_name: acl name 2464 * 2465 * Check permission before getting osix acls, the posix acls are identified by 2466 * @acl_name. 2467 * 2468 * Return: Returns 0 if permission is granted. 2469 */ 2470 int security_inode_get_acl(struct mnt_idmap *idmap, 2471 struct dentry *dentry, const char *acl_name) 2472 { 2473 if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) 2474 return 0; 2475 return call_int_hook(inode_get_acl, idmap, dentry, acl_name); 2476 } 2477 2478 /** 2479 * security_inode_remove_acl() - Check if removing a posix acl is allowed 2480 * @idmap: idmap of the mount 2481 * @dentry: file 2482 * @acl_name: acl name 2483 * 2484 * Check permission before removing posix acls, the posix acls are identified 2485 * by @acl_name. 2486 * 2487 * Return: Returns 0 if permission is granted. 2488 */ 2489 int security_inode_remove_acl(struct mnt_idmap *idmap, 2490 struct dentry *dentry, const char *acl_name) 2491 { 2492 if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) 2493 return 0; 2494 return call_int_hook(inode_remove_acl, idmap, dentry, acl_name); 2495 } 2496 2497 /** 2498 * security_inode_post_remove_acl() - Update inode security after rm posix acls 2499 * @idmap: idmap of the mount 2500 * @dentry: file 2501 * @acl_name: acl name 2502 * 2503 * Update inode security data after successfully removing posix acls on 2504 * @dentry in @idmap. The posix acls are identified by @acl_name. 2505 */ 2506 void security_inode_post_remove_acl(struct mnt_idmap *idmap, 2507 struct dentry *dentry, const char *acl_name) 2508 { 2509 if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) 2510 return; 2511 call_void_hook(inode_post_remove_acl, idmap, dentry, acl_name); 2512 } 2513 2514 /** 2515 * security_inode_post_setxattr() - Update the inode after a setxattr operation 2516 * @dentry: file 2517 * @name: xattr name 2518 * @value: xattr value 2519 * @size: xattr value size 2520 * @flags: flags 2521 * 2522 * Update inode security field after successful setxattr operation. 2523 */ 2524 void security_inode_post_setxattr(struct dentry *dentry, const char *name, 2525 const void *value, size_t size, int flags) 2526 { 2527 if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) 2528 return; 2529 call_void_hook(inode_post_setxattr, dentry, name, value, size, flags); 2530 } 2531 2532 /** 2533 * security_inode_getxattr() - Check if xattr access is allowed 2534 * @dentry: file 2535 * @name: xattr name 2536 * 2537 * Check permission before obtaining the extended attributes identified by 2538 * @name for @dentry. 2539 * 2540 * Return: Returns 0 if permission is granted. 2541 */ 2542 int security_inode_getxattr(struct dentry *dentry, const char *name) 2543 { 2544 if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) 2545 return 0; 2546 return call_int_hook(inode_getxattr, dentry, name); 2547 } 2548 2549 /** 2550 * security_inode_listxattr() - Check if listing xattrs is allowed 2551 * @dentry: file 2552 * 2553 * Check permission before obtaining the list of extended attribute names for 2554 * @dentry. 2555 * 2556 * Return: Returns 0 if permission is granted. 2557 */ 2558 int security_inode_listxattr(struct dentry *dentry) 2559 { 2560 if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) 2561 return 0; 2562 return call_int_hook(inode_listxattr, dentry); 2563 } 2564 2565 /** 2566 * security_inode_removexattr() - Check if removing an xattr is allowed 2567 * @idmap: idmap of the mount 2568 * @dentry: file 2569 * @name: xattr name 2570 * 2571 * This hook performs the desired permission checks before setting the extended 2572 * attributes (xattrs) on @dentry. It is important to note that we have some 2573 * additional logic before the main LSM implementation calls to detect if we 2574 * need to perform an additional capability check at the LSM layer. 2575 * 2576 * Normally we enforce a capability check prior to executing the various LSM 2577 * hook implementations, but if a LSM wants to avoid this capability check, 2578 * it can register a 'inode_xattr_skipcap' hook and return a value of 1 for 2579 * xattrs that it wants to avoid the capability check, leaving the LSM fully 2580 * responsible for enforcing the access control for the specific xattr. If all 2581 * of the enabled LSMs refrain from registering a 'inode_xattr_skipcap' hook, 2582 * or return a 0 (the default return value), the capability check is still 2583 * performed. If no 'inode_xattr_skipcap' hooks are registered the capability 2584 * check is performed. 2585 * 2586 * Return: Returns 0 if permission is granted. 2587 */ 2588 int security_inode_removexattr(struct mnt_idmap *idmap, 2589 struct dentry *dentry, const char *name) 2590 { 2591 int rc; 2592 2593 if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) 2594 return 0; 2595 2596 /* enforce the capability checks at the lsm layer, if needed */ 2597 if (!call_int_hook(inode_xattr_skipcap, name)) { 2598 rc = cap_inode_removexattr(idmap, dentry, name); 2599 if (rc) 2600 return rc; 2601 } 2602 2603 return call_int_hook(inode_removexattr, idmap, dentry, name); 2604 } 2605 2606 /** 2607 * security_inode_post_removexattr() - Update the inode after a removexattr op 2608 * @dentry: file 2609 * @name: xattr name 2610 * 2611 * Update the inode after a successful removexattr operation. 2612 */ 2613 void security_inode_post_removexattr(struct dentry *dentry, const char *name) 2614 { 2615 if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) 2616 return; 2617 call_void_hook(inode_post_removexattr, dentry, name); 2618 } 2619 2620 /** 2621 * security_inode_need_killpriv() - Check if security_inode_killpriv() required 2622 * @dentry: associated dentry 2623 * 2624 * Called when an inode has been changed to determine if 2625 * security_inode_killpriv() should be called. 2626 * 2627 * Return: Return <0 on error to abort the inode change operation, return 0 if 2628 * security_inode_killpriv() does not need to be called, return >0 if 2629 * security_inode_killpriv() does need to be called. 2630 */ 2631 int security_inode_need_killpriv(struct dentry *dentry) 2632 { 2633 return call_int_hook(inode_need_killpriv, dentry); 2634 } 2635 2636 /** 2637 * security_inode_killpriv() - The setuid bit is removed, update LSM state 2638 * @idmap: idmap of the mount 2639 * @dentry: associated dentry 2640 * 2641 * The @dentry's setuid bit is being removed. Remove similar security labels. 2642 * Called with the dentry->d_inode->i_mutex held. 2643 * 2644 * Return: Return 0 on success. If error is returned, then the operation 2645 * causing setuid bit removal is failed. 2646 */ 2647 int security_inode_killpriv(struct mnt_idmap *idmap, 2648 struct dentry *dentry) 2649 { 2650 return call_int_hook(inode_killpriv, idmap, dentry); 2651 } 2652 2653 /** 2654 * security_inode_getsecurity() - Get the xattr security label of an inode 2655 * @idmap: idmap of the mount 2656 * @inode: inode 2657 * @name: xattr name 2658 * @buffer: security label buffer 2659 * @alloc: allocation flag 2660 * 2661 * Retrieve a copy of the extended attribute representation of the security 2662 * label associated with @name for @inode via @buffer. Note that @name is the 2663 * remainder of the attribute name after the security prefix has been removed. 2664 * @alloc is used to specify if the call should return a value via the buffer 2665 * or just the value length. 2666 * 2667 * Return: Returns size of buffer on success. 2668 */ 2669 int security_inode_getsecurity(struct mnt_idmap *idmap, 2670 struct inode *inode, const char *name, 2671 void **buffer, bool alloc) 2672 { 2673 if (unlikely(IS_PRIVATE(inode))) 2674 return LSM_RET_DEFAULT(inode_getsecurity); 2675 2676 return call_int_hook(inode_getsecurity, idmap, inode, name, buffer, 2677 alloc); 2678 } 2679 2680 /** 2681 * security_inode_setsecurity() - Set the xattr security label of an inode 2682 * @inode: inode 2683 * @name: xattr name 2684 * @value: security label 2685 * @size: length of security label 2686 * @flags: flags 2687 * 2688 * Set the security label associated with @name for @inode from the extended 2689 * attribute value @value. @size indicates the size of the @value in bytes. 2690 * @flags may be XATTR_CREATE, XATTR_REPLACE, or 0. Note that @name is the 2691 * remainder of the attribute name after the security. prefix has been removed. 2692 * 2693 * Return: Returns 0 on success. 2694 */ 2695 int security_inode_setsecurity(struct inode *inode, const char *name, 2696 const void *value, size_t size, int flags) 2697 { 2698 if (unlikely(IS_PRIVATE(inode))) 2699 return LSM_RET_DEFAULT(inode_setsecurity); 2700 2701 return call_int_hook(inode_setsecurity, inode, name, value, size, 2702 flags); 2703 } 2704 2705 /** 2706 * security_inode_listsecurity() - List the xattr security label names 2707 * @inode: inode 2708 * @buffer: buffer 2709 * @buffer_size: size of buffer 2710 * 2711 * Copy the extended attribute names for the security labels associated with 2712 * @inode into @buffer. The maximum size of @buffer is specified by 2713 * @buffer_size. @buffer may be NULL to request the size of the buffer 2714 * required. 2715 * 2716 * Return: Returns number of bytes used/required on success. 2717 */ 2718 int security_inode_listsecurity(struct inode *inode, 2719 char *buffer, size_t buffer_size) 2720 { 2721 if (unlikely(IS_PRIVATE(inode))) 2722 return 0; 2723 return call_int_hook(inode_listsecurity, inode, buffer, buffer_size); 2724 } 2725 EXPORT_SYMBOL(security_inode_listsecurity); 2726 2727 /** 2728 * security_inode_getlsmprop() - Get an inode's LSM data 2729 * @inode: inode 2730 * @prop: lsm specific information to return 2731 * 2732 * Get the lsm specific information associated with the node. 2733 */ 2734 void security_inode_getlsmprop(struct inode *inode, struct lsm_prop *prop) 2735 { 2736 call_void_hook(inode_getlsmprop, inode, prop); 2737 } 2738 2739 /** 2740 * security_inode_copy_up() - Create new creds for an overlayfs copy-up op 2741 * @src: union dentry of copy-up file 2742 * @new: newly created creds 2743 * 2744 * A file is about to be copied up from lower layer to upper layer of overlay 2745 * filesystem. Security module can prepare a set of new creds and modify as 2746 * need be and return new creds. Caller will switch to new creds temporarily to 2747 * create new file and release newly allocated creds. 2748 * 2749 * Return: Returns 0 on success or a negative error code on error. 2750 */ 2751 int security_inode_copy_up(struct dentry *src, struct cred **new) 2752 { 2753 return call_int_hook(inode_copy_up, src, new); 2754 } 2755 EXPORT_SYMBOL(security_inode_copy_up); 2756 2757 /** 2758 * security_inode_copy_up_xattr() - Filter xattrs in an overlayfs copy-up op 2759 * @src: union dentry of copy-up file 2760 * @name: xattr name 2761 * 2762 * Filter the xattrs being copied up when a unioned file is copied up from a 2763 * lower layer to the union/overlay layer. The caller is responsible for 2764 * reading and writing the xattrs, this hook is merely a filter. 2765 * 2766 * Return: Returns 0 to accept the xattr, -ECANCELED to discard the xattr, 2767 * -EOPNOTSUPP if the security module does not know about attribute, 2768 * or a negative error code to abort the copy up. 2769 */ 2770 int security_inode_copy_up_xattr(struct dentry *src, const char *name) 2771 { 2772 int rc; 2773 2774 rc = call_int_hook(inode_copy_up_xattr, src, name); 2775 if (rc != LSM_RET_DEFAULT(inode_copy_up_xattr)) 2776 return rc; 2777 2778 return LSM_RET_DEFAULT(inode_copy_up_xattr); 2779 } 2780 EXPORT_SYMBOL(security_inode_copy_up_xattr); 2781 2782 /** 2783 * security_inode_setintegrity() - Set the inode's integrity data 2784 * @inode: inode 2785 * @type: type of integrity, e.g. hash digest, signature, etc 2786 * @value: the integrity value 2787 * @size: size of the integrity value 2788 * 2789 * Register a verified integrity measurement of a inode with LSMs. 2790 * LSMs should free the previously saved data if @value is NULL. 2791 * 2792 * Return: Returns 0 on success, negative values on failure. 2793 */ 2794 int security_inode_setintegrity(const struct inode *inode, 2795 enum lsm_integrity_type type, const void *value, 2796 size_t size) 2797 { 2798 return call_int_hook(inode_setintegrity, inode, type, value, size); 2799 } 2800 EXPORT_SYMBOL(security_inode_setintegrity); 2801 2802 /** 2803 * security_kernfs_init_security() - Init LSM context for a kernfs node 2804 * @kn_dir: parent kernfs node 2805 * @kn: the kernfs node to initialize 2806 * 2807 * Initialize the security context of a newly created kernfs node based on its 2808 * own and its parent's attributes. 2809 * 2810 * Return: Returns 0 if permission is granted. 2811 */ 2812 int security_kernfs_init_security(struct kernfs_node *kn_dir, 2813 struct kernfs_node *kn) 2814 { 2815 return call_int_hook(kernfs_init_security, kn_dir, kn); 2816 } 2817 2818 /** 2819 * security_file_permission() - Check file permissions 2820 * @file: file 2821 * @mask: requested permissions 2822 * 2823 * Check file permissions before accessing an open file. This hook is called 2824 * by various operations that read or write files. A security module can use 2825 * this hook to perform additional checking on these operations, e.g. to 2826 * revalidate permissions on use to support privilege bracketing or policy 2827 * changes. Notice that this hook is used when the actual read/write 2828 * operations are performed, whereas the inode_security_ops hook is called when 2829 * a file is opened (as well as many other operations). Although this hook can 2830 * be used to revalidate permissions for various system call operations that 2831 * read or write files, it does not address the revalidation of permissions for 2832 * memory-mapped files. Security modules must handle this separately if they 2833 * need such revalidation. 2834 * 2835 * Return: Returns 0 if permission is granted. 2836 */ 2837 int security_file_permission(struct file *file, int mask) 2838 { 2839 return call_int_hook(file_permission, file, mask); 2840 } 2841 2842 /** 2843 * security_file_alloc() - Allocate and init a file's LSM blob 2844 * @file: the file 2845 * 2846 * Allocate and attach a security structure to the file->f_security field. The 2847 * security field is initialized to NULL when the structure is first created. 2848 * 2849 * Return: Return 0 if the hook is successful and permission is granted. 2850 */ 2851 int security_file_alloc(struct file *file) 2852 { 2853 int rc = lsm_file_alloc(file); 2854 2855 if (rc) 2856 return rc; 2857 rc = call_int_hook(file_alloc_security, file); 2858 if (unlikely(rc)) 2859 security_file_free(file); 2860 return rc; 2861 } 2862 2863 /** 2864 * security_file_release() - Perform actions before releasing the file ref 2865 * @file: the file 2866 * 2867 * Perform actions before releasing the last reference to a file. 2868 */ 2869 void security_file_release(struct file *file) 2870 { 2871 call_void_hook(file_release, file); 2872 } 2873 2874 /** 2875 * security_file_free() - Free a file's LSM blob 2876 * @file: the file 2877 * 2878 * Deallocate and free any security structures stored in file->f_security. 2879 */ 2880 void security_file_free(struct file *file) 2881 { 2882 void *blob; 2883 2884 call_void_hook(file_free_security, file); 2885 2886 blob = file->f_security; 2887 if (blob) { 2888 file->f_security = NULL; 2889 kmem_cache_free(lsm_file_cache, blob); 2890 } 2891 } 2892 2893 /** 2894 * security_file_ioctl() - Check if an ioctl is allowed 2895 * @file: associated file 2896 * @cmd: ioctl cmd 2897 * @arg: ioctl arguments 2898 * 2899 * Check permission for an ioctl operation on @file. Note that @arg sometimes 2900 * represents a user space pointer; in other cases, it may be a simple integer 2901 * value. When @arg represents a user space pointer, it should never be used 2902 * by the security module. 2903 * 2904 * Return: Returns 0 if permission is granted. 2905 */ 2906 int security_file_ioctl(struct file *file, unsigned int cmd, unsigned long arg) 2907 { 2908 return call_int_hook(file_ioctl, file, cmd, arg); 2909 } 2910 EXPORT_SYMBOL_GPL(security_file_ioctl); 2911 2912 /** 2913 * security_file_ioctl_compat() - Check if an ioctl is allowed in compat mode 2914 * @file: associated file 2915 * @cmd: ioctl cmd 2916 * @arg: ioctl arguments 2917 * 2918 * Compat version of security_file_ioctl() that correctly handles 32-bit 2919 * processes running on 64-bit kernels. 2920 * 2921 * Return: Returns 0 if permission is granted. 2922 */ 2923 int security_file_ioctl_compat(struct file *file, unsigned int cmd, 2924 unsigned long arg) 2925 { 2926 return call_int_hook(file_ioctl_compat, file, cmd, arg); 2927 } 2928 EXPORT_SYMBOL_GPL(security_file_ioctl_compat); 2929 2930 static inline unsigned long mmap_prot(struct file *file, unsigned long prot) 2931 { 2932 /* 2933 * Does we have PROT_READ and does the application expect 2934 * it to imply PROT_EXEC? If not, nothing to talk about... 2935 */ 2936 if ((prot & (PROT_READ | PROT_EXEC)) != PROT_READ) 2937 return prot; 2938 if (!(current->personality & READ_IMPLIES_EXEC)) 2939 return prot; 2940 /* 2941 * if that's an anonymous mapping, let it. 2942 */ 2943 if (!file) 2944 return prot | PROT_EXEC; 2945 /* 2946 * ditto if it's not on noexec mount, except that on !MMU we need 2947 * NOMMU_MAP_EXEC (== VM_MAYEXEC) in this case 2948 */ 2949 if (!path_noexec(&file->f_path)) { 2950 #ifndef CONFIG_MMU 2951 if (file->f_op->mmap_capabilities) { 2952 unsigned caps = file->f_op->mmap_capabilities(file); 2953 if (!(caps & NOMMU_MAP_EXEC)) 2954 return prot; 2955 } 2956 #endif 2957 return prot | PROT_EXEC; 2958 } 2959 /* anything on noexec mount won't get PROT_EXEC */ 2960 return prot; 2961 } 2962 2963 /** 2964 * security_mmap_file() - Check if mmap'ing a file is allowed 2965 * @file: file 2966 * @prot: protection applied by the kernel 2967 * @flags: flags 2968 * 2969 * Check permissions for a mmap operation. The @file may be NULL, e.g. if 2970 * mapping anonymous memory. 2971 * 2972 * Return: Returns 0 if permission is granted. 2973 */ 2974 int security_mmap_file(struct file *file, unsigned long prot, 2975 unsigned long flags) 2976 { 2977 return call_int_hook(mmap_file, file, prot, mmap_prot(file, prot), 2978 flags); 2979 } 2980 2981 /** 2982 * security_mmap_addr() - Check if mmap'ing an address is allowed 2983 * @addr: address 2984 * 2985 * Check permissions for a mmap operation at @addr. 2986 * 2987 * Return: Returns 0 if permission is granted. 2988 */ 2989 int security_mmap_addr(unsigned long addr) 2990 { 2991 return call_int_hook(mmap_addr, addr); 2992 } 2993 2994 /** 2995 * security_file_mprotect() - Check if changing memory protections is allowed 2996 * @vma: memory region 2997 * @reqprot: application requested protection 2998 * @prot: protection applied by the kernel 2999 * 3000 * Check permissions before changing memory access permissions. 3001 * 3002 * Return: Returns 0 if permission is granted. 3003 */ 3004 int security_file_mprotect(struct vm_area_struct *vma, unsigned long reqprot, 3005 unsigned long prot) 3006 { 3007 return call_int_hook(file_mprotect, vma, reqprot, prot); 3008 } 3009 3010 /** 3011 * security_file_lock() - Check if a file lock is allowed 3012 * @file: file 3013 * @cmd: lock operation (e.g. F_RDLCK, F_WRLCK) 3014 * 3015 * Check permission before performing file locking operations. Note the hook 3016 * mediates both flock and fcntl style locks. 3017 * 3018 * Return: Returns 0 if permission is granted. 3019 */ 3020 int security_file_lock(struct file *file, unsigned int cmd) 3021 { 3022 return call_int_hook(file_lock, file, cmd); 3023 } 3024 3025 /** 3026 * security_file_fcntl() - Check if fcntl() op is allowed 3027 * @file: file 3028 * @cmd: fcntl command 3029 * @arg: command argument 3030 * 3031 * Check permission before allowing the file operation specified by @cmd from 3032 * being performed on the file @file. Note that @arg sometimes represents a 3033 * user space pointer; in other cases, it may be a simple integer value. When 3034 * @arg represents a user space pointer, it should never be used by the 3035 * security module. 3036 * 3037 * Return: Returns 0 if permission is granted. 3038 */ 3039 int security_file_fcntl(struct file *file, unsigned int cmd, unsigned long arg) 3040 { 3041 return call_int_hook(file_fcntl, file, cmd, arg); 3042 } 3043 3044 /** 3045 * security_file_set_fowner() - Set the file owner info in the LSM blob 3046 * @file: the file 3047 * 3048 * Save owner security information (typically from current->security) in 3049 * file->f_security for later use by the send_sigiotask hook. 3050 * 3051 * This hook is called with file->f_owner.lock held. 3052 * 3053 * Return: Returns 0 on success. 3054 */ 3055 void security_file_set_fowner(struct file *file) 3056 { 3057 call_void_hook(file_set_fowner, file); 3058 } 3059 3060 /** 3061 * security_file_send_sigiotask() - Check if sending SIGIO/SIGURG is allowed 3062 * @tsk: target task 3063 * @fown: signal sender 3064 * @sig: signal to be sent, SIGIO is sent if 0 3065 * 3066 * Check permission for the file owner @fown to send SIGIO or SIGURG to the 3067 * process @tsk. Note that this hook is sometimes called from interrupt. Note 3068 * that the fown_struct, @fown, is never outside the context of a struct file, 3069 * so the file structure (and associated security information) can always be 3070 * obtained: container_of(fown, struct file, f_owner). 3071 * 3072 * Return: Returns 0 if permission is granted. 3073 */ 3074 int security_file_send_sigiotask(struct task_struct *tsk, 3075 struct fown_struct *fown, int sig) 3076 { 3077 return call_int_hook(file_send_sigiotask, tsk, fown, sig); 3078 } 3079 3080 /** 3081 * security_file_receive() - Check if receiving a file via IPC is allowed 3082 * @file: file being received 3083 * 3084 * This hook allows security modules to control the ability of a process to 3085 * receive an open file descriptor via socket IPC. 3086 * 3087 * Return: Returns 0 if permission is granted. 3088 */ 3089 int security_file_receive(struct file *file) 3090 { 3091 return call_int_hook(file_receive, file); 3092 } 3093 3094 /** 3095 * security_file_open() - Save open() time state for late use by the LSM 3096 * @file: 3097 * 3098 * Save open-time permission checking state for later use upon file_permission, 3099 * and recheck access if anything has changed since inode_permission. 3100 * 3101 * Return: Returns 0 if permission is granted. 3102 */ 3103 int security_file_open(struct file *file) 3104 { 3105 return call_int_hook(file_open, file); 3106 } 3107 3108 /** 3109 * security_file_post_open() - Evaluate a file after it has been opened 3110 * @file: the file 3111 * @mask: access mask 3112 * 3113 * Evaluate an opened file and the access mask requested with open(). The hook 3114 * is useful for LSMs that require the file content to be available in order to 3115 * make decisions. 3116 * 3117 * Return: Returns 0 if permission is granted. 3118 */ 3119 int security_file_post_open(struct file *file, int mask) 3120 { 3121 return call_int_hook(file_post_open, file, mask); 3122 } 3123 EXPORT_SYMBOL_GPL(security_file_post_open); 3124 3125 /** 3126 * security_file_truncate() - Check if truncating a file is allowed 3127 * @file: file 3128 * 3129 * Check permission before truncating a file, i.e. using ftruncate. Note that 3130 * truncation permission may also be checked based on the path, using the 3131 * @path_truncate hook. 3132 * 3133 * Return: Returns 0 if permission is granted. 3134 */ 3135 int security_file_truncate(struct file *file) 3136 { 3137 return call_int_hook(file_truncate, file); 3138 } 3139 3140 /** 3141 * security_task_alloc() - Allocate a task's LSM blob 3142 * @task: the task 3143 * @clone_flags: flags indicating what is being shared 3144 * 3145 * Handle allocation of task-related resources. 3146 * 3147 * Return: Returns a zero on success, negative values on failure. 3148 */ 3149 int security_task_alloc(struct task_struct *task, unsigned long clone_flags) 3150 { 3151 int rc = lsm_task_alloc(task); 3152 3153 if (rc) 3154 return rc; 3155 rc = call_int_hook(task_alloc, task, clone_flags); 3156 if (unlikely(rc)) 3157 security_task_free(task); 3158 return rc; 3159 } 3160 3161 /** 3162 * security_task_free() - Free a task's LSM blob and related resources 3163 * @task: task 3164 * 3165 * Handle release of task-related resources. Note that this can be called from 3166 * interrupt context. 3167 */ 3168 void security_task_free(struct task_struct *task) 3169 { 3170 call_void_hook(task_free, task); 3171 3172 kfree(task->security); 3173 task->security = NULL; 3174 } 3175 3176 /** 3177 * security_cred_alloc_blank() - Allocate the min memory to allow cred_transfer 3178 * @cred: credentials 3179 * @gfp: gfp flags 3180 * 3181 * Only allocate sufficient memory and attach to @cred such that 3182 * cred_transfer() will not get ENOMEM. 3183 * 3184 * Return: Returns 0 on success, negative values on failure. 3185 */ 3186 int security_cred_alloc_blank(struct cred *cred, gfp_t gfp) 3187 { 3188 int rc = lsm_cred_alloc(cred, gfp); 3189 3190 if (rc) 3191 return rc; 3192 3193 rc = call_int_hook(cred_alloc_blank, cred, gfp); 3194 if (unlikely(rc)) 3195 security_cred_free(cred); 3196 return rc; 3197 } 3198 3199 /** 3200 * security_cred_free() - Free the cred's LSM blob and associated resources 3201 * @cred: credentials 3202 * 3203 * Deallocate and clear the cred->security field in a set of credentials. 3204 */ 3205 void security_cred_free(struct cred *cred) 3206 { 3207 /* 3208 * There is a failure case in prepare_creds() that 3209 * may result in a call here with ->security being NULL. 3210 */ 3211 if (unlikely(cred->security == NULL)) 3212 return; 3213 3214 call_void_hook(cred_free, cred); 3215 3216 kfree(cred->security); 3217 cred->security = NULL; 3218 } 3219 3220 /** 3221 * security_prepare_creds() - Prepare a new set of credentials 3222 * @new: new credentials 3223 * @old: original credentials 3224 * @gfp: gfp flags 3225 * 3226 * Prepare a new set of credentials by copying the data from the old set. 3227 * 3228 * Return: Returns 0 on success, negative values on failure. 3229 */ 3230 int security_prepare_creds(struct cred *new, const struct cred *old, gfp_t gfp) 3231 { 3232 int rc = lsm_cred_alloc(new, gfp); 3233 3234 if (rc) 3235 return rc; 3236 3237 rc = call_int_hook(cred_prepare, new, old, gfp); 3238 if (unlikely(rc)) 3239 security_cred_free(new); 3240 return rc; 3241 } 3242 3243 /** 3244 * security_transfer_creds() - Transfer creds 3245 * @new: target credentials 3246 * @old: original credentials 3247 * 3248 * Transfer data from original creds to new creds. 3249 */ 3250 void security_transfer_creds(struct cred *new, const struct cred *old) 3251 { 3252 call_void_hook(cred_transfer, new, old); 3253 } 3254 3255 /** 3256 * security_cred_getsecid() - Get the secid from a set of credentials 3257 * @c: credentials 3258 * @secid: secid value 3259 * 3260 * Retrieve the security identifier of the cred structure @c. In case of 3261 * failure, @secid will be set to zero. 3262 */ 3263 void security_cred_getsecid(const struct cred *c, u32 *secid) 3264 { 3265 *secid = 0; 3266 call_void_hook(cred_getsecid, c, secid); 3267 } 3268 EXPORT_SYMBOL(security_cred_getsecid); 3269 3270 /** 3271 * security_cred_getlsmprop() - Get the LSM data from a set of credentials 3272 * @c: credentials 3273 * @prop: destination for the LSM data 3274 * 3275 * Retrieve the security data of the cred structure @c. In case of 3276 * failure, @prop will be cleared. 3277 */ 3278 void security_cred_getlsmprop(const struct cred *c, struct lsm_prop *prop) 3279 { 3280 lsmprop_init(prop); 3281 call_void_hook(cred_getlsmprop, c, prop); 3282 } 3283 EXPORT_SYMBOL(security_cred_getlsmprop); 3284 3285 /** 3286 * security_kernel_act_as() - Set the kernel credentials to act as secid 3287 * @new: credentials 3288 * @secid: secid 3289 * 3290 * Set the credentials for a kernel service to act as (subjective context). 3291 * The current task must be the one that nominated @secid. 3292 * 3293 * Return: Returns 0 if successful. 3294 */ 3295 int security_kernel_act_as(struct cred *new, u32 secid) 3296 { 3297 return call_int_hook(kernel_act_as, new, secid); 3298 } 3299 3300 /** 3301 * security_kernel_create_files_as() - Set file creation context using an inode 3302 * @new: target credentials 3303 * @inode: reference inode 3304 * 3305 * Set the file creation context in a set of credentials to be the same as the 3306 * objective context of the specified inode. The current task must be the one 3307 * that nominated @inode. 3308 * 3309 * Return: Returns 0 if successful. 3310 */ 3311 int security_kernel_create_files_as(struct cred *new, struct inode *inode) 3312 { 3313 return call_int_hook(kernel_create_files_as, new, inode); 3314 } 3315 3316 /** 3317 * security_kernel_module_request() - Check if loading a module is allowed 3318 * @kmod_name: module name 3319 * 3320 * Ability to trigger the kernel to automatically upcall to userspace for 3321 * userspace to load a kernel module with the given name. 3322 * 3323 * Return: Returns 0 if successful. 3324 */ 3325 int security_kernel_module_request(char *kmod_name) 3326 { 3327 return call_int_hook(kernel_module_request, kmod_name); 3328 } 3329 3330 /** 3331 * security_kernel_read_file() - Read a file specified by userspace 3332 * @file: file 3333 * @id: file identifier 3334 * @contents: trust if security_kernel_post_read_file() will be called 3335 * 3336 * Read a file specified by userspace. 3337 * 3338 * Return: Returns 0 if permission is granted. 3339 */ 3340 int security_kernel_read_file(struct file *file, enum kernel_read_file_id id, 3341 bool contents) 3342 { 3343 return call_int_hook(kernel_read_file, file, id, contents); 3344 } 3345 EXPORT_SYMBOL_GPL(security_kernel_read_file); 3346 3347 /** 3348 * security_kernel_post_read_file() - Read a file specified by userspace 3349 * @file: file 3350 * @buf: file contents 3351 * @size: size of file contents 3352 * @id: file identifier 3353 * 3354 * Read a file specified by userspace. This must be paired with a prior call 3355 * to security_kernel_read_file() call that indicated this hook would also be 3356 * called, see security_kernel_read_file() for more information. 3357 * 3358 * Return: Returns 0 if permission is granted. 3359 */ 3360 int security_kernel_post_read_file(struct file *file, char *buf, loff_t size, 3361 enum kernel_read_file_id id) 3362 { 3363 return call_int_hook(kernel_post_read_file, file, buf, size, id); 3364 } 3365 EXPORT_SYMBOL_GPL(security_kernel_post_read_file); 3366 3367 /** 3368 * security_kernel_load_data() - Load data provided by userspace 3369 * @id: data identifier 3370 * @contents: true if security_kernel_post_load_data() will be called 3371 * 3372 * Load data provided by userspace. 3373 * 3374 * Return: Returns 0 if permission is granted. 3375 */ 3376 int security_kernel_load_data(enum kernel_load_data_id id, bool contents) 3377 { 3378 return call_int_hook(kernel_load_data, id, contents); 3379 } 3380 EXPORT_SYMBOL_GPL(security_kernel_load_data); 3381 3382 /** 3383 * security_kernel_post_load_data() - Load userspace data from a non-file source 3384 * @buf: data 3385 * @size: size of data 3386 * @id: data identifier 3387 * @description: text description of data, specific to the id value 3388 * 3389 * Load data provided by a non-file source (usually userspace buffer). This 3390 * must be paired with a prior security_kernel_load_data() call that indicated 3391 * this hook would also be called, see security_kernel_load_data() for more 3392 * information. 3393 * 3394 * Return: Returns 0 if permission is granted. 3395 */ 3396 int security_kernel_post_load_data(char *buf, loff_t size, 3397 enum kernel_load_data_id id, 3398 char *description) 3399 { 3400 return call_int_hook(kernel_post_load_data, buf, size, id, description); 3401 } 3402 EXPORT_SYMBOL_GPL(security_kernel_post_load_data); 3403 3404 /** 3405 * security_task_fix_setuid() - Update LSM with new user id attributes 3406 * @new: updated credentials 3407 * @old: credentials being replaced 3408 * @flags: LSM_SETID_* flag values 3409 * 3410 * Update the module's state after setting one or more of the user identity 3411 * attributes of the current process. The @flags parameter indicates which of 3412 * the set*uid system calls invoked this hook. If @new is the set of 3413 * credentials that will be installed. Modifications should be made to this 3414 * rather than to @current->cred. 3415 * 3416 * Return: Returns 0 on success. 3417 */ 3418 int security_task_fix_setuid(struct cred *new, const struct cred *old, 3419 int flags) 3420 { 3421 return call_int_hook(task_fix_setuid, new, old, flags); 3422 } 3423 3424 /** 3425 * security_task_fix_setgid() - Update LSM with new group id attributes 3426 * @new: updated credentials 3427 * @old: credentials being replaced 3428 * @flags: LSM_SETID_* flag value 3429 * 3430 * Update the module's state after setting one or more of the group identity 3431 * attributes of the current process. The @flags parameter indicates which of 3432 * the set*gid system calls invoked this hook. @new is the set of credentials 3433 * that will be installed. Modifications should be made to this rather than to 3434 * @current->cred. 3435 * 3436 * Return: Returns 0 on success. 3437 */ 3438 int security_task_fix_setgid(struct cred *new, const struct cred *old, 3439 int flags) 3440 { 3441 return call_int_hook(task_fix_setgid, new, old, flags); 3442 } 3443 3444 /** 3445 * security_task_fix_setgroups() - Update LSM with new supplementary groups 3446 * @new: updated credentials 3447 * @old: credentials being replaced 3448 * 3449 * Update the module's state after setting the supplementary group identity 3450 * attributes of the current process. @new is the set of credentials that will 3451 * be installed. Modifications should be made to this rather than to 3452 * @current->cred. 3453 * 3454 * Return: Returns 0 on success. 3455 */ 3456 int security_task_fix_setgroups(struct cred *new, const struct cred *old) 3457 { 3458 return call_int_hook(task_fix_setgroups, new, old); 3459 } 3460 3461 /** 3462 * security_task_setpgid() - Check if setting the pgid is allowed 3463 * @p: task being modified 3464 * @pgid: new pgid 3465 * 3466 * Check permission before setting the process group identifier of the process 3467 * @p to @pgid. 3468 * 3469 * Return: Returns 0 if permission is granted. 3470 */ 3471 int security_task_setpgid(struct task_struct *p, pid_t pgid) 3472 { 3473 return call_int_hook(task_setpgid, p, pgid); 3474 } 3475 3476 /** 3477 * security_task_getpgid() - Check if getting the pgid is allowed 3478 * @p: task 3479 * 3480 * Check permission before getting the process group identifier of the process 3481 * @p. 3482 * 3483 * Return: Returns 0 if permission is granted. 3484 */ 3485 int security_task_getpgid(struct task_struct *p) 3486 { 3487 return call_int_hook(task_getpgid, p); 3488 } 3489 3490 /** 3491 * security_task_getsid() - Check if getting the session id is allowed 3492 * @p: task 3493 * 3494 * Check permission before getting the session identifier of the process @p. 3495 * 3496 * Return: Returns 0 if permission is granted. 3497 */ 3498 int security_task_getsid(struct task_struct *p) 3499 { 3500 return call_int_hook(task_getsid, p); 3501 } 3502 3503 /** 3504 * security_current_getlsmprop_subj() - Current task's subjective LSM data 3505 * @prop: lsm specific information 3506 * 3507 * Retrieve the subjective security identifier of the current task and return 3508 * it in @prop. 3509 */ 3510 void security_current_getlsmprop_subj(struct lsm_prop *prop) 3511 { 3512 lsmprop_init(prop); 3513 call_void_hook(current_getlsmprop_subj, prop); 3514 } 3515 EXPORT_SYMBOL(security_current_getlsmprop_subj); 3516 3517 /** 3518 * security_task_getlsmprop_obj() - Get a task's objective LSM data 3519 * @p: target task 3520 * @prop: lsm specific information 3521 * 3522 * Retrieve the objective security identifier of the task_struct in @p and 3523 * return it in @prop. 3524 */ 3525 void security_task_getlsmprop_obj(struct task_struct *p, struct lsm_prop *prop) 3526 { 3527 lsmprop_init(prop); 3528 call_void_hook(task_getlsmprop_obj, p, prop); 3529 } 3530 EXPORT_SYMBOL(security_task_getlsmprop_obj); 3531 3532 /** 3533 * security_task_setnice() - Check if setting a task's nice value is allowed 3534 * @p: target task 3535 * @nice: nice value 3536 * 3537 * Check permission before setting the nice value of @p to @nice. 3538 * 3539 * Return: Returns 0 if permission is granted. 3540 */ 3541 int security_task_setnice(struct task_struct *p, int nice) 3542 { 3543 return call_int_hook(task_setnice, p, nice); 3544 } 3545 3546 /** 3547 * security_task_setioprio() - Check if setting a task's ioprio is allowed 3548 * @p: target task 3549 * @ioprio: ioprio value 3550 * 3551 * Check permission before setting the ioprio value of @p to @ioprio. 3552 * 3553 * Return: Returns 0 if permission is granted. 3554 */ 3555 int security_task_setioprio(struct task_struct *p, int ioprio) 3556 { 3557 return call_int_hook(task_setioprio, p, ioprio); 3558 } 3559 3560 /** 3561 * security_task_getioprio() - Check if getting a task's ioprio is allowed 3562 * @p: task 3563 * 3564 * Check permission before getting the ioprio value of @p. 3565 * 3566 * Return: Returns 0 if permission is granted. 3567 */ 3568 int security_task_getioprio(struct task_struct *p) 3569 { 3570 return call_int_hook(task_getioprio, p); 3571 } 3572 3573 /** 3574 * security_task_prlimit() - Check if get/setting resources limits is allowed 3575 * @cred: current task credentials 3576 * @tcred: target task credentials 3577 * @flags: LSM_PRLIMIT_* flag bits indicating a get/set/both 3578 * 3579 * Check permission before getting and/or setting the resource limits of 3580 * another task. 3581 * 3582 * Return: Returns 0 if permission is granted. 3583 */ 3584 int security_task_prlimit(const struct cred *cred, const struct cred *tcred, 3585 unsigned int flags) 3586 { 3587 return call_int_hook(task_prlimit, cred, tcred, flags); 3588 } 3589 3590 /** 3591 * security_task_setrlimit() - Check if setting a new rlimit value is allowed 3592 * @p: target task's group leader 3593 * @resource: resource whose limit is being set 3594 * @new_rlim: new resource limit 3595 * 3596 * Check permission before setting the resource limits of process @p for 3597 * @resource to @new_rlim. The old resource limit values can be examined by 3598 * dereferencing (p->signal->rlim + resource). 3599 * 3600 * Return: Returns 0 if permission is granted. 3601 */ 3602 int security_task_setrlimit(struct task_struct *p, unsigned int resource, 3603 struct rlimit *new_rlim) 3604 { 3605 return call_int_hook(task_setrlimit, p, resource, new_rlim); 3606 } 3607 3608 /** 3609 * security_task_setscheduler() - Check if setting sched policy/param is allowed 3610 * @p: target task 3611 * 3612 * Check permission before setting scheduling policy and/or parameters of 3613 * process @p. 3614 * 3615 * Return: Returns 0 if permission is granted. 3616 */ 3617 int security_task_setscheduler(struct task_struct *p) 3618 { 3619 return call_int_hook(task_setscheduler, p); 3620 } 3621 3622 /** 3623 * security_task_getscheduler() - Check if getting scheduling info is allowed 3624 * @p: target task 3625 * 3626 * Check permission before obtaining scheduling information for process @p. 3627 * 3628 * Return: Returns 0 if permission is granted. 3629 */ 3630 int security_task_getscheduler(struct task_struct *p) 3631 { 3632 return call_int_hook(task_getscheduler, p); 3633 } 3634 3635 /** 3636 * security_task_movememory() - Check if moving memory is allowed 3637 * @p: task 3638 * 3639 * Check permission before moving memory owned by process @p. 3640 * 3641 * Return: Returns 0 if permission is granted. 3642 */ 3643 int security_task_movememory(struct task_struct *p) 3644 { 3645 return call_int_hook(task_movememory, p); 3646 } 3647 3648 /** 3649 * security_task_kill() - Check if sending a signal is allowed 3650 * @p: target process 3651 * @info: signal information 3652 * @sig: signal value 3653 * @cred: credentials of the signal sender, NULL if @current 3654 * 3655 * Check permission before sending signal @sig to @p. @info can be NULL, the 3656 * constant 1, or a pointer to a kernel_siginfo structure. If @info is 1 or 3657 * SI_FROMKERNEL(info) is true, then the signal should be viewed as coming from 3658 * the kernel and should typically be permitted. SIGIO signals are handled 3659 * separately by the send_sigiotask hook in file_security_ops. 3660 * 3661 * Return: Returns 0 if permission is granted. 3662 */ 3663 int security_task_kill(struct task_struct *p, struct kernel_siginfo *info, 3664 int sig, const struct cred *cred) 3665 { 3666 return call_int_hook(task_kill, p, info, sig, cred); 3667 } 3668 3669 /** 3670 * security_task_prctl() - Check if a prctl op is allowed 3671 * @option: operation 3672 * @arg2: argument 3673 * @arg3: argument 3674 * @arg4: argument 3675 * @arg5: argument 3676 * 3677 * Check permission before performing a process control operation on the 3678 * current process. 3679 * 3680 * Return: Return -ENOSYS if no-one wanted to handle this op, any other value 3681 * to cause prctl() to return immediately with that value. 3682 */ 3683 int security_task_prctl(int option, unsigned long arg2, unsigned long arg3, 3684 unsigned long arg4, unsigned long arg5) 3685 { 3686 int thisrc; 3687 int rc = LSM_RET_DEFAULT(task_prctl); 3688 struct lsm_static_call *scall; 3689 3690 lsm_for_each_hook(scall, task_prctl) { 3691 thisrc = scall->hl->hook.task_prctl(option, arg2, arg3, arg4, arg5); 3692 if (thisrc != LSM_RET_DEFAULT(task_prctl)) { 3693 rc = thisrc; 3694 if (thisrc != 0) 3695 break; 3696 } 3697 } 3698 return rc; 3699 } 3700 3701 /** 3702 * security_task_to_inode() - Set the security attributes of a task's inode 3703 * @p: task 3704 * @inode: inode 3705 * 3706 * Set the security attributes for an inode based on an associated task's 3707 * security attributes, e.g. for /proc/pid inodes. 3708 */ 3709 void security_task_to_inode(struct task_struct *p, struct inode *inode) 3710 { 3711 call_void_hook(task_to_inode, p, inode); 3712 } 3713 3714 /** 3715 * security_create_user_ns() - Check if creating a new userns is allowed 3716 * @cred: prepared creds 3717 * 3718 * Check permission prior to creating a new user namespace. 3719 * 3720 * Return: Returns 0 if successful, otherwise < 0 error code. 3721 */ 3722 int security_create_user_ns(const struct cred *cred) 3723 { 3724 return call_int_hook(userns_create, cred); 3725 } 3726 3727 /** 3728 * security_ipc_permission() - Check if sysv ipc access is allowed 3729 * @ipcp: ipc permission structure 3730 * @flag: requested permissions 3731 * 3732 * Check permissions for access to IPC. 3733 * 3734 * Return: Returns 0 if permission is granted. 3735 */ 3736 int security_ipc_permission(struct kern_ipc_perm *ipcp, short flag) 3737 { 3738 return call_int_hook(ipc_permission, ipcp, flag); 3739 } 3740 3741 /** 3742 * security_ipc_getlsmprop() - Get the sysv ipc object LSM data 3743 * @ipcp: ipc permission structure 3744 * @prop: pointer to lsm information 3745 * 3746 * Get the lsm information associated with the ipc object. 3747 */ 3748 3749 void security_ipc_getlsmprop(struct kern_ipc_perm *ipcp, struct lsm_prop *prop) 3750 { 3751 lsmprop_init(prop); 3752 call_void_hook(ipc_getlsmprop, ipcp, prop); 3753 } 3754 3755 /** 3756 * security_msg_msg_alloc() - Allocate a sysv ipc message LSM blob 3757 * @msg: message structure 3758 * 3759 * Allocate and attach a security structure to the msg->security field. The 3760 * security field is initialized to NULL when the structure is first created. 3761 * 3762 * Return: Return 0 if operation was successful and permission is granted. 3763 */ 3764 int security_msg_msg_alloc(struct msg_msg *msg) 3765 { 3766 int rc = lsm_msg_msg_alloc(msg); 3767 3768 if (unlikely(rc)) 3769 return rc; 3770 rc = call_int_hook(msg_msg_alloc_security, msg); 3771 if (unlikely(rc)) 3772 security_msg_msg_free(msg); 3773 return rc; 3774 } 3775 3776 /** 3777 * security_msg_msg_free() - Free a sysv ipc message LSM blob 3778 * @msg: message structure 3779 * 3780 * Deallocate the security structure for this message. 3781 */ 3782 void security_msg_msg_free(struct msg_msg *msg) 3783 { 3784 call_void_hook(msg_msg_free_security, msg); 3785 kfree(msg->security); 3786 msg->security = NULL; 3787 } 3788 3789 /** 3790 * security_msg_queue_alloc() - Allocate a sysv ipc msg queue LSM blob 3791 * @msq: sysv ipc permission structure 3792 * 3793 * Allocate and attach a security structure to @msg. The security field is 3794 * initialized to NULL when the structure is first created. 3795 * 3796 * Return: Returns 0 if operation was successful and permission is granted. 3797 */ 3798 int security_msg_queue_alloc(struct kern_ipc_perm *msq) 3799 { 3800 int rc = lsm_ipc_alloc(msq); 3801 3802 if (unlikely(rc)) 3803 return rc; 3804 rc = call_int_hook(msg_queue_alloc_security, msq); 3805 if (unlikely(rc)) 3806 security_msg_queue_free(msq); 3807 return rc; 3808 } 3809 3810 /** 3811 * security_msg_queue_free() - Free a sysv ipc msg queue LSM blob 3812 * @msq: sysv ipc permission structure 3813 * 3814 * Deallocate security field @perm->security for the message queue. 3815 */ 3816 void security_msg_queue_free(struct kern_ipc_perm *msq) 3817 { 3818 call_void_hook(msg_queue_free_security, msq); 3819 kfree(msq->security); 3820 msq->security = NULL; 3821 } 3822 3823 /** 3824 * security_msg_queue_associate() - Check if a msg queue operation is allowed 3825 * @msq: sysv ipc permission structure 3826 * @msqflg: operation flags 3827 * 3828 * Check permission when a message queue is requested through the msgget system 3829 * call. This hook is only called when returning the message queue identifier 3830 * for an existing message queue, not when a new message queue is created. 3831 * 3832 * Return: Return 0 if permission is granted. 3833 */ 3834 int security_msg_queue_associate(struct kern_ipc_perm *msq, int msqflg) 3835 { 3836 return call_int_hook(msg_queue_associate, msq, msqflg); 3837 } 3838 3839 /** 3840 * security_msg_queue_msgctl() - Check if a msg queue operation is allowed 3841 * @msq: sysv ipc permission structure 3842 * @cmd: operation 3843 * 3844 * Check permission when a message control operation specified by @cmd is to be 3845 * performed on the message queue with permissions. 3846 * 3847 * Return: Returns 0 if permission is granted. 3848 */ 3849 int security_msg_queue_msgctl(struct kern_ipc_perm *msq, int cmd) 3850 { 3851 return call_int_hook(msg_queue_msgctl, msq, cmd); 3852 } 3853 3854 /** 3855 * security_msg_queue_msgsnd() - Check if sending a sysv ipc message is allowed 3856 * @msq: sysv ipc permission structure 3857 * @msg: message 3858 * @msqflg: operation flags 3859 * 3860 * Check permission before a message, @msg, is enqueued on the message queue 3861 * with permissions specified in @msq. 3862 * 3863 * Return: Returns 0 if permission is granted. 3864 */ 3865 int security_msg_queue_msgsnd(struct kern_ipc_perm *msq, 3866 struct msg_msg *msg, int msqflg) 3867 { 3868 return call_int_hook(msg_queue_msgsnd, msq, msg, msqflg); 3869 } 3870 3871 /** 3872 * security_msg_queue_msgrcv() - Check if receiving a sysv ipc msg is allowed 3873 * @msq: sysv ipc permission structure 3874 * @msg: message 3875 * @target: target task 3876 * @type: type of message requested 3877 * @mode: operation flags 3878 * 3879 * Check permission before a message, @msg, is removed from the message queue. 3880 * The @target task structure contains a pointer to the process that will be 3881 * receiving the message (not equal to the current process when inline receives 3882 * are being performed). 3883 * 3884 * Return: Returns 0 if permission is granted. 3885 */ 3886 int security_msg_queue_msgrcv(struct kern_ipc_perm *msq, struct msg_msg *msg, 3887 struct task_struct *target, long type, int mode) 3888 { 3889 return call_int_hook(msg_queue_msgrcv, msq, msg, target, type, mode); 3890 } 3891 3892 /** 3893 * security_shm_alloc() - Allocate a sysv shm LSM blob 3894 * @shp: sysv ipc permission structure 3895 * 3896 * Allocate and attach a security structure to the @shp security field. The 3897 * security field is initialized to NULL when the structure is first created. 3898 * 3899 * Return: Returns 0 if operation was successful and permission is granted. 3900 */ 3901 int security_shm_alloc(struct kern_ipc_perm *shp) 3902 { 3903 int rc = lsm_ipc_alloc(shp); 3904 3905 if (unlikely(rc)) 3906 return rc; 3907 rc = call_int_hook(shm_alloc_security, shp); 3908 if (unlikely(rc)) 3909 security_shm_free(shp); 3910 return rc; 3911 } 3912 3913 /** 3914 * security_shm_free() - Free a sysv shm LSM blob 3915 * @shp: sysv ipc permission structure 3916 * 3917 * Deallocate the security structure @perm->security for the memory segment. 3918 */ 3919 void security_shm_free(struct kern_ipc_perm *shp) 3920 { 3921 call_void_hook(shm_free_security, shp); 3922 kfree(shp->security); 3923 shp->security = NULL; 3924 } 3925 3926 /** 3927 * security_shm_associate() - Check if a sysv shm operation is allowed 3928 * @shp: sysv ipc permission structure 3929 * @shmflg: operation flags 3930 * 3931 * Check permission when a shared memory region is requested through the shmget 3932 * system call. This hook is only called when returning the shared memory 3933 * region identifier for an existing region, not when a new shared memory 3934 * region is created. 3935 * 3936 * Return: Returns 0 if permission is granted. 3937 */ 3938 int security_shm_associate(struct kern_ipc_perm *shp, int shmflg) 3939 { 3940 return call_int_hook(shm_associate, shp, shmflg); 3941 } 3942 3943 /** 3944 * security_shm_shmctl() - Check if a sysv shm operation is allowed 3945 * @shp: sysv ipc permission structure 3946 * @cmd: operation 3947 * 3948 * Check permission when a shared memory control operation specified by @cmd is 3949 * to be performed on the shared memory region with permissions in @shp. 3950 * 3951 * Return: Return 0 if permission is granted. 3952 */ 3953 int security_shm_shmctl(struct kern_ipc_perm *shp, int cmd) 3954 { 3955 return call_int_hook(shm_shmctl, shp, cmd); 3956 } 3957 3958 /** 3959 * security_shm_shmat() - Check if a sysv shm attach operation is allowed 3960 * @shp: sysv ipc permission structure 3961 * @shmaddr: address of memory region to attach 3962 * @shmflg: operation flags 3963 * 3964 * Check permissions prior to allowing the shmat system call to attach the 3965 * shared memory segment with permissions @shp to the data segment of the 3966 * calling process. The attaching address is specified by @shmaddr. 3967 * 3968 * Return: Returns 0 if permission is granted. 3969 */ 3970 int security_shm_shmat(struct kern_ipc_perm *shp, 3971 char __user *shmaddr, int shmflg) 3972 { 3973 return call_int_hook(shm_shmat, shp, shmaddr, shmflg); 3974 } 3975 3976 /** 3977 * security_sem_alloc() - Allocate a sysv semaphore LSM blob 3978 * @sma: sysv ipc permission structure 3979 * 3980 * Allocate and attach a security structure to the @sma security field. The 3981 * security field is initialized to NULL when the structure is first created. 3982 * 3983 * Return: Returns 0 if operation was successful and permission is granted. 3984 */ 3985 int security_sem_alloc(struct kern_ipc_perm *sma) 3986 { 3987 int rc = lsm_ipc_alloc(sma); 3988 3989 if (unlikely(rc)) 3990 return rc; 3991 rc = call_int_hook(sem_alloc_security, sma); 3992 if (unlikely(rc)) 3993 security_sem_free(sma); 3994 return rc; 3995 } 3996 3997 /** 3998 * security_sem_free() - Free a sysv semaphore LSM blob 3999 * @sma: sysv ipc permission structure 4000 * 4001 * Deallocate security structure @sma->security for the semaphore. 4002 */ 4003 void security_sem_free(struct kern_ipc_perm *sma) 4004 { 4005 call_void_hook(sem_free_security, sma); 4006 kfree(sma->security); 4007 sma->security = NULL; 4008 } 4009 4010 /** 4011 * security_sem_associate() - Check if a sysv semaphore operation is allowed 4012 * @sma: sysv ipc permission structure 4013 * @semflg: operation flags 4014 * 4015 * Check permission when a semaphore is requested through the semget system 4016 * call. This hook is only called when returning the semaphore identifier for 4017 * an existing semaphore, not when a new one must be created. 4018 * 4019 * Return: Returns 0 if permission is granted. 4020 */ 4021 int security_sem_associate(struct kern_ipc_perm *sma, int semflg) 4022 { 4023 return call_int_hook(sem_associate, sma, semflg); 4024 } 4025 4026 /** 4027 * security_sem_semctl() - Check if a sysv semaphore operation is allowed 4028 * @sma: sysv ipc permission structure 4029 * @cmd: operation 4030 * 4031 * Check permission when a semaphore operation specified by @cmd is to be 4032 * performed on the semaphore. 4033 * 4034 * Return: Returns 0 if permission is granted. 4035 */ 4036 int security_sem_semctl(struct kern_ipc_perm *sma, int cmd) 4037 { 4038 return call_int_hook(sem_semctl, sma, cmd); 4039 } 4040 4041 /** 4042 * security_sem_semop() - Check if a sysv semaphore operation is allowed 4043 * @sma: sysv ipc permission structure 4044 * @sops: operations to perform 4045 * @nsops: number of operations 4046 * @alter: flag indicating changes will be made 4047 * 4048 * Check permissions before performing operations on members of the semaphore 4049 * set. If the @alter flag is nonzero, the semaphore set may be modified. 4050 * 4051 * Return: Returns 0 if permission is granted. 4052 */ 4053 int security_sem_semop(struct kern_ipc_perm *sma, struct sembuf *sops, 4054 unsigned nsops, int alter) 4055 { 4056 return call_int_hook(sem_semop, sma, sops, nsops, alter); 4057 } 4058 4059 /** 4060 * security_d_instantiate() - Populate an inode's LSM state based on a dentry 4061 * @dentry: dentry 4062 * @inode: inode 4063 * 4064 * Fill in @inode security information for a @dentry if allowed. 4065 */ 4066 void security_d_instantiate(struct dentry *dentry, struct inode *inode) 4067 { 4068 if (unlikely(inode && IS_PRIVATE(inode))) 4069 return; 4070 call_void_hook(d_instantiate, dentry, inode); 4071 } 4072 EXPORT_SYMBOL(security_d_instantiate); 4073 4074 /* 4075 * Please keep this in sync with it's counterpart in security/lsm_syscalls.c 4076 */ 4077 4078 /** 4079 * security_getselfattr - Read an LSM attribute of the current process. 4080 * @attr: which attribute to return 4081 * @uctx: the user-space destination for the information, or NULL 4082 * @size: pointer to the size of space available to receive the data 4083 * @flags: special handling options. LSM_FLAG_SINGLE indicates that only 4084 * attributes associated with the LSM identified in the passed @ctx be 4085 * reported. 4086 * 4087 * A NULL value for @uctx can be used to get both the number of attributes 4088 * and the size of the data. 4089 * 4090 * Returns the number of attributes found on success, negative value 4091 * on error. @size is reset to the total size of the data. 4092 * If @size is insufficient to contain the data -E2BIG is returned. 4093 */ 4094 int security_getselfattr(unsigned int attr, struct lsm_ctx __user *uctx, 4095 u32 __user *size, u32 flags) 4096 { 4097 struct lsm_static_call *scall; 4098 struct lsm_ctx lctx = { .id = LSM_ID_UNDEF, }; 4099 u8 __user *base = (u8 __user *)uctx; 4100 u32 entrysize; 4101 u32 total = 0; 4102 u32 left; 4103 bool toobig = false; 4104 bool single = false; 4105 int count = 0; 4106 int rc; 4107 4108 if (attr == LSM_ATTR_UNDEF) 4109 return -EINVAL; 4110 if (size == NULL) 4111 return -EINVAL; 4112 if (get_user(left, size)) 4113 return -EFAULT; 4114 4115 if (flags) { 4116 /* 4117 * Only flag supported is LSM_FLAG_SINGLE 4118 */ 4119 if (flags != LSM_FLAG_SINGLE || !uctx) 4120 return -EINVAL; 4121 if (copy_from_user(&lctx, uctx, sizeof(lctx))) 4122 return -EFAULT; 4123 /* 4124 * If the LSM ID isn't specified it is an error. 4125 */ 4126 if (lctx.id == LSM_ID_UNDEF) 4127 return -EINVAL; 4128 single = true; 4129 } 4130 4131 /* 4132 * In the usual case gather all the data from the LSMs. 4133 * In the single case only get the data from the LSM specified. 4134 */ 4135 lsm_for_each_hook(scall, getselfattr) { 4136 if (single && lctx.id != scall->hl->lsmid->id) 4137 continue; 4138 entrysize = left; 4139 if (base) 4140 uctx = (struct lsm_ctx __user *)(base + total); 4141 rc = scall->hl->hook.getselfattr(attr, uctx, &entrysize, flags); 4142 if (rc == -EOPNOTSUPP) { 4143 rc = 0; 4144 continue; 4145 } 4146 if (rc == -E2BIG) { 4147 rc = 0; 4148 left = 0; 4149 toobig = true; 4150 } else if (rc < 0) 4151 return rc; 4152 else 4153 left -= entrysize; 4154 4155 total += entrysize; 4156 count += rc; 4157 if (single) 4158 break; 4159 } 4160 if (put_user(total, size)) 4161 return -EFAULT; 4162 if (toobig) 4163 return -E2BIG; 4164 if (count == 0) 4165 return LSM_RET_DEFAULT(getselfattr); 4166 return count; 4167 } 4168 4169 /* 4170 * Please keep this in sync with it's counterpart in security/lsm_syscalls.c 4171 */ 4172 4173 /** 4174 * security_setselfattr - Set an LSM attribute on the current process. 4175 * @attr: which attribute to set 4176 * @uctx: the user-space source for the information 4177 * @size: the size of the data 4178 * @flags: reserved for future use, must be 0 4179 * 4180 * Set an LSM attribute for the current process. The LSM, attribute 4181 * and new value are included in @uctx. 4182 * 4183 * Returns 0 on success, -EINVAL if the input is inconsistent, -EFAULT 4184 * if the user buffer is inaccessible, E2BIG if size is too big, or an 4185 * LSM specific failure. 4186 */ 4187 int security_setselfattr(unsigned int attr, struct lsm_ctx __user *uctx, 4188 u32 size, u32 flags) 4189 { 4190 struct lsm_static_call *scall; 4191 struct lsm_ctx *lctx; 4192 int rc = LSM_RET_DEFAULT(setselfattr); 4193 u64 required_len; 4194 4195 if (flags) 4196 return -EINVAL; 4197 if (size < sizeof(*lctx)) 4198 return -EINVAL; 4199 if (size > PAGE_SIZE) 4200 return -E2BIG; 4201 4202 lctx = memdup_user(uctx, size); 4203 if (IS_ERR(lctx)) 4204 return PTR_ERR(lctx); 4205 4206 if (size < lctx->len || 4207 check_add_overflow(sizeof(*lctx), lctx->ctx_len, &required_len) || 4208 lctx->len < required_len) { 4209 rc = -EINVAL; 4210 goto free_out; 4211 } 4212 4213 lsm_for_each_hook(scall, setselfattr) 4214 if ((scall->hl->lsmid->id) == lctx->id) { 4215 rc = scall->hl->hook.setselfattr(attr, lctx, size, flags); 4216 break; 4217 } 4218 4219 free_out: 4220 kfree(lctx); 4221 return rc; 4222 } 4223 4224 /** 4225 * security_getprocattr() - Read an attribute for a task 4226 * @p: the task 4227 * @lsmid: LSM identification 4228 * @name: attribute name 4229 * @value: attribute value 4230 * 4231 * Read attribute @name for task @p and store it into @value if allowed. 4232 * 4233 * Return: Returns the length of @value on success, a negative value otherwise. 4234 */ 4235 int security_getprocattr(struct task_struct *p, int lsmid, const char *name, 4236 char **value) 4237 { 4238 struct lsm_static_call *scall; 4239 4240 lsm_for_each_hook(scall, getprocattr) { 4241 if (lsmid != 0 && lsmid != scall->hl->lsmid->id) 4242 continue; 4243 return scall->hl->hook.getprocattr(p, name, value); 4244 } 4245 return LSM_RET_DEFAULT(getprocattr); 4246 } 4247 4248 /** 4249 * security_setprocattr() - Set an attribute for a task 4250 * @lsmid: LSM identification 4251 * @name: attribute name 4252 * @value: attribute value 4253 * @size: attribute value size 4254 * 4255 * Write (set) the current task's attribute @name to @value, size @size if 4256 * allowed. 4257 * 4258 * Return: Returns bytes written on success, a negative value otherwise. 4259 */ 4260 int security_setprocattr(int lsmid, const char *name, void *value, size_t size) 4261 { 4262 struct lsm_static_call *scall; 4263 4264 lsm_for_each_hook(scall, setprocattr) { 4265 if (lsmid != 0 && lsmid != scall->hl->lsmid->id) 4266 continue; 4267 return scall->hl->hook.setprocattr(name, value, size); 4268 } 4269 return LSM_RET_DEFAULT(setprocattr); 4270 } 4271 4272 /** 4273 * security_netlink_send() - Save info and check if netlink sending is allowed 4274 * @sk: sending socket 4275 * @skb: netlink message 4276 * 4277 * Save security information for a netlink message so that permission checking 4278 * can be performed when the message is processed. The security information 4279 * can be saved using the eff_cap field of the netlink_skb_parms structure. 4280 * Also may be used to provide fine grained control over message transmission. 4281 * 4282 * Return: Returns 0 if the information was successfully saved and message is 4283 * allowed to be transmitted. 4284 */ 4285 int security_netlink_send(struct sock *sk, struct sk_buff *skb) 4286 { 4287 return call_int_hook(netlink_send, sk, skb); 4288 } 4289 4290 /** 4291 * security_ismaclabel() - Check if the named attribute is a MAC label 4292 * @name: full extended attribute name 4293 * 4294 * Check if the extended attribute specified by @name represents a MAC label. 4295 * 4296 * Return: Returns 1 if name is a MAC attribute otherwise returns 0. 4297 */ 4298 int security_ismaclabel(const char *name) 4299 { 4300 return call_int_hook(ismaclabel, name); 4301 } 4302 EXPORT_SYMBOL(security_ismaclabel); 4303 4304 /** 4305 * security_secid_to_secctx() - Convert a secid to a secctx 4306 * @secid: secid 4307 * @secdata: secctx 4308 * @seclen: secctx length 4309 * 4310 * Convert secid to security context. If @secdata is NULL the length of the 4311 * result will be returned in @seclen, but no @secdata will be returned. This 4312 * does mean that the length could change between calls to check the length and 4313 * the next call which actually allocates and returns the @secdata. 4314 * 4315 * Return: Return 0 on success, error on failure. 4316 */ 4317 int security_secid_to_secctx(u32 secid, char **secdata, u32 *seclen) 4318 { 4319 return call_int_hook(secid_to_secctx, secid, secdata, seclen); 4320 } 4321 EXPORT_SYMBOL(security_secid_to_secctx); 4322 4323 /** 4324 * security_lsmprop_to_secctx() - Convert a lsm_prop to a secctx 4325 * @prop: lsm specific information 4326 * @secdata: secctx 4327 * @seclen: secctx length 4328 * 4329 * Convert a @prop entry to security context. If @secdata is NULL the 4330 * length of the result will be returned in @seclen, but no @secdata 4331 * will be returned. This does mean that the length could change between 4332 * calls to check the length and the next call which actually allocates 4333 * and returns the @secdata. 4334 * 4335 * Return: Return 0 on success, error on failure. 4336 */ 4337 int security_lsmprop_to_secctx(struct lsm_prop *prop, char **secdata, 4338 u32 *seclen) 4339 { 4340 return call_int_hook(lsmprop_to_secctx, prop, secdata, seclen); 4341 } 4342 EXPORT_SYMBOL(security_lsmprop_to_secctx); 4343 4344 /** 4345 * security_secctx_to_secid() - Convert a secctx to a secid 4346 * @secdata: secctx 4347 * @seclen: length of secctx 4348 * @secid: secid 4349 * 4350 * Convert security context to secid. 4351 * 4352 * Return: Returns 0 on success, error on failure. 4353 */ 4354 int security_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid) 4355 { 4356 *secid = 0; 4357 return call_int_hook(secctx_to_secid, secdata, seclen, secid); 4358 } 4359 EXPORT_SYMBOL(security_secctx_to_secid); 4360 4361 /** 4362 * security_release_secctx() - Free a secctx buffer 4363 * @secdata: secctx 4364 * @seclen: length of secctx 4365 * 4366 * Release the security context. 4367 */ 4368 void security_release_secctx(char *secdata, u32 seclen) 4369 { 4370 call_void_hook(release_secctx, secdata, seclen); 4371 } 4372 EXPORT_SYMBOL(security_release_secctx); 4373 4374 /** 4375 * security_inode_invalidate_secctx() - Invalidate an inode's security label 4376 * @inode: inode 4377 * 4378 * Notify the security module that it must revalidate the security context of 4379 * an inode. 4380 */ 4381 void security_inode_invalidate_secctx(struct inode *inode) 4382 { 4383 call_void_hook(inode_invalidate_secctx, inode); 4384 } 4385 EXPORT_SYMBOL(security_inode_invalidate_secctx); 4386 4387 /** 4388 * security_inode_notifysecctx() - Notify the LSM of an inode's security label 4389 * @inode: inode 4390 * @ctx: secctx 4391 * @ctxlen: length of secctx 4392 * 4393 * Notify the security module of what the security context of an inode should 4394 * be. Initializes the incore security context managed by the security module 4395 * for this inode. Example usage: NFS client invokes this hook to initialize 4396 * the security context in its incore inode to the value provided by the server 4397 * for the file when the server returned the file's attributes to the client. 4398 * Must be called with inode->i_mutex locked. 4399 * 4400 * Return: Returns 0 on success, error on failure. 4401 */ 4402 int security_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen) 4403 { 4404 return call_int_hook(inode_notifysecctx, inode, ctx, ctxlen); 4405 } 4406 EXPORT_SYMBOL(security_inode_notifysecctx); 4407 4408 /** 4409 * security_inode_setsecctx() - Change the security label of an inode 4410 * @dentry: inode 4411 * @ctx: secctx 4412 * @ctxlen: length of secctx 4413 * 4414 * Change the security context of an inode. Updates the incore security 4415 * context managed by the security module and invokes the fs code as needed 4416 * (via __vfs_setxattr_noperm) to update any backing xattrs that represent the 4417 * context. Example usage: NFS server invokes this hook to change the security 4418 * context in its incore inode and on the backing filesystem to a value 4419 * provided by the client on a SETATTR operation. Must be called with 4420 * inode->i_mutex locked. 4421 * 4422 * Return: Returns 0 on success, error on failure. 4423 */ 4424 int security_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen) 4425 { 4426 return call_int_hook(inode_setsecctx, dentry, ctx, ctxlen); 4427 } 4428 EXPORT_SYMBOL(security_inode_setsecctx); 4429 4430 /** 4431 * security_inode_getsecctx() - Get the security label of an inode 4432 * @inode: inode 4433 * @ctx: secctx 4434 * @ctxlen: length of secctx 4435 * 4436 * On success, returns 0 and fills out @ctx and @ctxlen with the security 4437 * context for the given @inode. 4438 * 4439 * Return: Returns 0 on success, error on failure. 4440 */ 4441 int security_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen) 4442 { 4443 return call_int_hook(inode_getsecctx, inode, ctx, ctxlen); 4444 } 4445 EXPORT_SYMBOL(security_inode_getsecctx); 4446 4447 #ifdef CONFIG_WATCH_QUEUE 4448 /** 4449 * security_post_notification() - Check if a watch notification can be posted 4450 * @w_cred: credentials of the task that set the watch 4451 * @cred: credentials of the task which triggered the watch 4452 * @n: the notification 4453 * 4454 * Check to see if a watch notification can be posted to a particular queue. 4455 * 4456 * Return: Returns 0 if permission is granted. 4457 */ 4458 int security_post_notification(const struct cred *w_cred, 4459 const struct cred *cred, 4460 struct watch_notification *n) 4461 { 4462 return call_int_hook(post_notification, w_cred, cred, n); 4463 } 4464 #endif /* CONFIG_WATCH_QUEUE */ 4465 4466 #ifdef CONFIG_KEY_NOTIFICATIONS 4467 /** 4468 * security_watch_key() - Check if a task is allowed to watch for key events 4469 * @key: the key to watch 4470 * 4471 * Check to see if a process is allowed to watch for event notifications from 4472 * a key or keyring. 4473 * 4474 * Return: Returns 0 if permission is granted. 4475 */ 4476 int security_watch_key(struct key *key) 4477 { 4478 return call_int_hook(watch_key, key); 4479 } 4480 #endif /* CONFIG_KEY_NOTIFICATIONS */ 4481 4482 #ifdef CONFIG_SECURITY_NETWORK 4483 /** 4484 * security_unix_stream_connect() - Check if a AF_UNIX stream is allowed 4485 * @sock: originating sock 4486 * @other: peer sock 4487 * @newsk: new sock 4488 * 4489 * Check permissions before establishing a Unix domain stream connection 4490 * between @sock and @other. 4491 * 4492 * The @unix_stream_connect and @unix_may_send hooks were necessary because 4493 * Linux provides an alternative to the conventional file name space for Unix 4494 * domain sockets. Whereas binding and connecting to sockets in the file name 4495 * space is mediated by the typical file permissions (and caught by the mknod 4496 * and permission hooks in inode_security_ops), binding and connecting to 4497 * sockets in the abstract name space is completely unmediated. Sufficient 4498 * control of Unix domain sockets in the abstract name space isn't possible 4499 * using only the socket layer hooks, since we need to know the actual target 4500 * socket, which is not looked up until we are inside the af_unix code. 4501 * 4502 * Return: Returns 0 if permission is granted. 4503 */ 4504 int security_unix_stream_connect(struct sock *sock, struct sock *other, 4505 struct sock *newsk) 4506 { 4507 return call_int_hook(unix_stream_connect, sock, other, newsk); 4508 } 4509 EXPORT_SYMBOL(security_unix_stream_connect); 4510 4511 /** 4512 * security_unix_may_send() - Check if AF_UNIX socket can send datagrams 4513 * @sock: originating sock 4514 * @other: peer sock 4515 * 4516 * Check permissions before connecting or sending datagrams from @sock to 4517 * @other. 4518 * 4519 * The @unix_stream_connect and @unix_may_send hooks were necessary because 4520 * Linux provides an alternative to the conventional file name space for Unix 4521 * domain sockets. Whereas binding and connecting to sockets in the file name 4522 * space is mediated by the typical file permissions (and caught by the mknod 4523 * and permission hooks in inode_security_ops), binding and connecting to 4524 * sockets in the abstract name space is completely unmediated. Sufficient 4525 * control of Unix domain sockets in the abstract name space isn't possible 4526 * using only the socket layer hooks, since we need to know the actual target 4527 * socket, which is not looked up until we are inside the af_unix code. 4528 * 4529 * Return: Returns 0 if permission is granted. 4530 */ 4531 int security_unix_may_send(struct socket *sock, struct socket *other) 4532 { 4533 return call_int_hook(unix_may_send, sock, other); 4534 } 4535 EXPORT_SYMBOL(security_unix_may_send); 4536 4537 /** 4538 * security_socket_create() - Check if creating a new socket is allowed 4539 * @family: protocol family 4540 * @type: communications type 4541 * @protocol: requested protocol 4542 * @kern: set to 1 if a kernel socket is requested 4543 * 4544 * Check permissions prior to creating a new socket. 4545 * 4546 * Return: Returns 0 if permission is granted. 4547 */ 4548 int security_socket_create(int family, int type, int protocol, int kern) 4549 { 4550 return call_int_hook(socket_create, family, type, protocol, kern); 4551 } 4552 4553 /** 4554 * security_socket_post_create() - Initialize a newly created socket 4555 * @sock: socket 4556 * @family: protocol family 4557 * @type: communications type 4558 * @protocol: requested protocol 4559 * @kern: set to 1 if a kernel socket is requested 4560 * 4561 * This hook allows a module to update or allocate a per-socket security 4562 * structure. Note that the security field was not added directly to the socket 4563 * structure, but rather, the socket security information is stored in the 4564 * associated inode. Typically, the inode alloc_security hook will allocate 4565 * and attach security information to SOCK_INODE(sock)->i_security. This hook 4566 * may be used to update the SOCK_INODE(sock)->i_security field with additional 4567 * information that wasn't available when the inode was allocated. 4568 * 4569 * Return: Returns 0 if permission is granted. 4570 */ 4571 int security_socket_post_create(struct socket *sock, int family, 4572 int type, int protocol, int kern) 4573 { 4574 return call_int_hook(socket_post_create, sock, family, type, 4575 protocol, kern); 4576 } 4577 4578 /** 4579 * security_socket_socketpair() - Check if creating a socketpair is allowed 4580 * @socka: first socket 4581 * @sockb: second socket 4582 * 4583 * Check permissions before creating a fresh pair of sockets. 4584 * 4585 * Return: Returns 0 if permission is granted and the connection was 4586 * established. 4587 */ 4588 int security_socket_socketpair(struct socket *socka, struct socket *sockb) 4589 { 4590 return call_int_hook(socket_socketpair, socka, sockb); 4591 } 4592 EXPORT_SYMBOL(security_socket_socketpair); 4593 4594 /** 4595 * security_socket_bind() - Check if a socket bind operation is allowed 4596 * @sock: socket 4597 * @address: requested bind address 4598 * @addrlen: length of address 4599 * 4600 * Check permission before socket protocol layer bind operation is performed 4601 * and the socket @sock is bound to the address specified in the @address 4602 * parameter. 4603 * 4604 * Return: Returns 0 if permission is granted. 4605 */ 4606 int security_socket_bind(struct socket *sock, 4607 struct sockaddr *address, int addrlen) 4608 { 4609 return call_int_hook(socket_bind, sock, address, addrlen); 4610 } 4611 4612 /** 4613 * security_socket_connect() - Check if a socket connect operation is allowed 4614 * @sock: socket 4615 * @address: address of remote connection point 4616 * @addrlen: length of address 4617 * 4618 * Check permission before socket protocol layer connect operation attempts to 4619 * connect socket @sock to a remote address, @address. 4620 * 4621 * Return: Returns 0 if permission is granted. 4622 */ 4623 int security_socket_connect(struct socket *sock, 4624 struct sockaddr *address, int addrlen) 4625 { 4626 return call_int_hook(socket_connect, sock, address, addrlen); 4627 } 4628 4629 /** 4630 * security_socket_listen() - Check if a socket is allowed to listen 4631 * @sock: socket 4632 * @backlog: connection queue size 4633 * 4634 * Check permission before socket protocol layer listen operation. 4635 * 4636 * Return: Returns 0 if permission is granted. 4637 */ 4638 int security_socket_listen(struct socket *sock, int backlog) 4639 { 4640 return call_int_hook(socket_listen, sock, backlog); 4641 } 4642 4643 /** 4644 * security_socket_accept() - Check if a socket is allowed to accept connections 4645 * @sock: listening socket 4646 * @newsock: newly creation connection socket 4647 * 4648 * Check permission before accepting a new connection. Note that the new 4649 * socket, @newsock, has been created and some information copied to it, but 4650 * the accept operation has not actually been performed. 4651 * 4652 * Return: Returns 0 if permission is granted. 4653 */ 4654 int security_socket_accept(struct socket *sock, struct socket *newsock) 4655 { 4656 return call_int_hook(socket_accept, sock, newsock); 4657 } 4658 4659 /** 4660 * security_socket_sendmsg() - Check if sending a message is allowed 4661 * @sock: sending socket 4662 * @msg: message to send 4663 * @size: size of message 4664 * 4665 * Check permission before transmitting a message to another socket. 4666 * 4667 * Return: Returns 0 if permission is granted. 4668 */ 4669 int security_socket_sendmsg(struct socket *sock, struct msghdr *msg, int size) 4670 { 4671 return call_int_hook(socket_sendmsg, sock, msg, size); 4672 } 4673 4674 /** 4675 * security_socket_recvmsg() - Check if receiving a message is allowed 4676 * @sock: receiving socket 4677 * @msg: message to receive 4678 * @size: size of message 4679 * @flags: operational flags 4680 * 4681 * Check permission before receiving a message from a socket. 4682 * 4683 * Return: Returns 0 if permission is granted. 4684 */ 4685 int security_socket_recvmsg(struct socket *sock, struct msghdr *msg, 4686 int size, int flags) 4687 { 4688 return call_int_hook(socket_recvmsg, sock, msg, size, flags); 4689 } 4690 4691 /** 4692 * security_socket_getsockname() - Check if reading the socket addr is allowed 4693 * @sock: socket 4694 * 4695 * Check permission before reading the local address (name) of the socket 4696 * object. 4697 * 4698 * Return: Returns 0 if permission is granted. 4699 */ 4700 int security_socket_getsockname(struct socket *sock) 4701 { 4702 return call_int_hook(socket_getsockname, sock); 4703 } 4704 4705 /** 4706 * security_socket_getpeername() - Check if reading the peer's addr is allowed 4707 * @sock: socket 4708 * 4709 * Check permission before the remote address (name) of a socket object. 4710 * 4711 * Return: Returns 0 if permission is granted. 4712 */ 4713 int security_socket_getpeername(struct socket *sock) 4714 { 4715 return call_int_hook(socket_getpeername, sock); 4716 } 4717 4718 /** 4719 * security_socket_getsockopt() - Check if reading a socket option is allowed 4720 * @sock: socket 4721 * @level: option's protocol level 4722 * @optname: option name 4723 * 4724 * Check permissions before retrieving the options associated with socket 4725 * @sock. 4726 * 4727 * Return: Returns 0 if permission is granted. 4728 */ 4729 int security_socket_getsockopt(struct socket *sock, int level, int optname) 4730 { 4731 return call_int_hook(socket_getsockopt, sock, level, optname); 4732 } 4733 4734 /** 4735 * security_socket_setsockopt() - Check if setting a socket option is allowed 4736 * @sock: socket 4737 * @level: option's protocol level 4738 * @optname: option name 4739 * 4740 * Check permissions before setting the options associated with socket @sock. 4741 * 4742 * Return: Returns 0 if permission is granted. 4743 */ 4744 int security_socket_setsockopt(struct socket *sock, int level, int optname) 4745 { 4746 return call_int_hook(socket_setsockopt, sock, level, optname); 4747 } 4748 4749 /** 4750 * security_socket_shutdown() - Checks if shutting down the socket is allowed 4751 * @sock: socket 4752 * @how: flag indicating how sends and receives are handled 4753 * 4754 * Checks permission before all or part of a connection on the socket @sock is 4755 * shut down. 4756 * 4757 * Return: Returns 0 if permission is granted. 4758 */ 4759 int security_socket_shutdown(struct socket *sock, int how) 4760 { 4761 return call_int_hook(socket_shutdown, sock, how); 4762 } 4763 4764 /** 4765 * security_sock_rcv_skb() - Check if an incoming network packet is allowed 4766 * @sk: destination sock 4767 * @skb: incoming packet 4768 * 4769 * Check permissions on incoming network packets. This hook is distinct from 4770 * Netfilter's IP input hooks since it is the first time that the incoming 4771 * sk_buff @skb has been associated with a particular socket, @sk. Must not 4772 * sleep inside this hook because some callers hold spinlocks. 4773 * 4774 * Return: Returns 0 if permission is granted. 4775 */ 4776 int security_sock_rcv_skb(struct sock *sk, struct sk_buff *skb) 4777 { 4778 return call_int_hook(socket_sock_rcv_skb, sk, skb); 4779 } 4780 EXPORT_SYMBOL(security_sock_rcv_skb); 4781 4782 /** 4783 * security_socket_getpeersec_stream() - Get the remote peer label 4784 * @sock: socket 4785 * @optval: destination buffer 4786 * @optlen: size of peer label copied into the buffer 4787 * @len: maximum size of the destination buffer 4788 * 4789 * This hook allows the security module to provide peer socket security state 4790 * for unix or connected tcp sockets to userspace via getsockopt SO_GETPEERSEC. 4791 * For tcp sockets this can be meaningful if the socket is associated with an 4792 * ipsec SA. 4793 * 4794 * Return: Returns 0 if all is well, otherwise, typical getsockopt return 4795 * values. 4796 */ 4797 int security_socket_getpeersec_stream(struct socket *sock, sockptr_t optval, 4798 sockptr_t optlen, unsigned int len) 4799 { 4800 return call_int_hook(socket_getpeersec_stream, sock, optval, optlen, 4801 len); 4802 } 4803 4804 /** 4805 * security_socket_getpeersec_dgram() - Get the remote peer label 4806 * @sock: socket 4807 * @skb: datagram packet 4808 * @secid: remote peer label secid 4809 * 4810 * This hook allows the security module to provide peer socket security state 4811 * for udp sockets on a per-packet basis to userspace via getsockopt 4812 * SO_GETPEERSEC. The application must first have indicated the IP_PASSSEC 4813 * option via getsockopt. It can then retrieve the security state returned by 4814 * this hook for a packet via the SCM_SECURITY ancillary message type. 4815 * 4816 * Return: Returns 0 on success, error on failure. 4817 */ 4818 int security_socket_getpeersec_dgram(struct socket *sock, 4819 struct sk_buff *skb, u32 *secid) 4820 { 4821 return call_int_hook(socket_getpeersec_dgram, sock, skb, secid); 4822 } 4823 EXPORT_SYMBOL(security_socket_getpeersec_dgram); 4824 4825 /** 4826 * lsm_sock_alloc - allocate a composite sock blob 4827 * @sock: the sock that needs a blob 4828 * @gfp: allocation mode 4829 * 4830 * Allocate the sock blob for all the modules 4831 * 4832 * Returns 0, or -ENOMEM if memory can't be allocated. 4833 */ 4834 static int lsm_sock_alloc(struct sock *sock, gfp_t gfp) 4835 { 4836 return lsm_blob_alloc(&sock->sk_security, blob_sizes.lbs_sock, gfp); 4837 } 4838 4839 /** 4840 * security_sk_alloc() - Allocate and initialize a sock's LSM blob 4841 * @sk: sock 4842 * @family: protocol family 4843 * @priority: gfp flags 4844 * 4845 * Allocate and attach a security structure to the sk->sk_security field, which 4846 * is used to copy security attributes between local stream sockets. 4847 * 4848 * Return: Returns 0 on success, error on failure. 4849 */ 4850 int security_sk_alloc(struct sock *sk, int family, gfp_t priority) 4851 { 4852 int rc = lsm_sock_alloc(sk, priority); 4853 4854 if (unlikely(rc)) 4855 return rc; 4856 rc = call_int_hook(sk_alloc_security, sk, family, priority); 4857 if (unlikely(rc)) 4858 security_sk_free(sk); 4859 return rc; 4860 } 4861 4862 /** 4863 * security_sk_free() - Free the sock's LSM blob 4864 * @sk: sock 4865 * 4866 * Deallocate security structure. 4867 */ 4868 void security_sk_free(struct sock *sk) 4869 { 4870 call_void_hook(sk_free_security, sk); 4871 kfree(sk->sk_security); 4872 sk->sk_security = NULL; 4873 } 4874 4875 /** 4876 * security_sk_clone() - Clone a sock's LSM state 4877 * @sk: original sock 4878 * @newsk: target sock 4879 * 4880 * Clone/copy security structure. 4881 */ 4882 void security_sk_clone(const struct sock *sk, struct sock *newsk) 4883 { 4884 call_void_hook(sk_clone_security, sk, newsk); 4885 } 4886 EXPORT_SYMBOL(security_sk_clone); 4887 4888 /** 4889 * security_sk_classify_flow() - Set a flow's secid based on socket 4890 * @sk: original socket 4891 * @flic: target flow 4892 * 4893 * Set the target flow's secid to socket's secid. 4894 */ 4895 void security_sk_classify_flow(const struct sock *sk, struct flowi_common *flic) 4896 { 4897 call_void_hook(sk_getsecid, sk, &flic->flowic_secid); 4898 } 4899 EXPORT_SYMBOL(security_sk_classify_flow); 4900 4901 /** 4902 * security_req_classify_flow() - Set a flow's secid based on request_sock 4903 * @req: request_sock 4904 * @flic: target flow 4905 * 4906 * Sets @flic's secid to @req's secid. 4907 */ 4908 void security_req_classify_flow(const struct request_sock *req, 4909 struct flowi_common *flic) 4910 { 4911 call_void_hook(req_classify_flow, req, flic); 4912 } 4913 EXPORT_SYMBOL(security_req_classify_flow); 4914 4915 /** 4916 * security_sock_graft() - Reconcile LSM state when grafting a sock on a socket 4917 * @sk: sock being grafted 4918 * @parent: target parent socket 4919 * 4920 * Sets @parent's inode secid to @sk's secid and update @sk with any necessary 4921 * LSM state from @parent. 4922 */ 4923 void security_sock_graft(struct sock *sk, struct socket *parent) 4924 { 4925 call_void_hook(sock_graft, sk, parent); 4926 } 4927 EXPORT_SYMBOL(security_sock_graft); 4928 4929 /** 4930 * security_inet_conn_request() - Set request_sock state using incoming connect 4931 * @sk: parent listening sock 4932 * @skb: incoming connection 4933 * @req: new request_sock 4934 * 4935 * Initialize the @req LSM state based on @sk and the incoming connect in @skb. 4936 * 4937 * Return: Returns 0 if permission is granted. 4938 */ 4939 int security_inet_conn_request(const struct sock *sk, 4940 struct sk_buff *skb, struct request_sock *req) 4941 { 4942 return call_int_hook(inet_conn_request, sk, skb, req); 4943 } 4944 EXPORT_SYMBOL(security_inet_conn_request); 4945 4946 /** 4947 * security_inet_csk_clone() - Set new sock LSM state based on request_sock 4948 * @newsk: new sock 4949 * @req: connection request_sock 4950 * 4951 * Set that LSM state of @sock using the LSM state from @req. 4952 */ 4953 void security_inet_csk_clone(struct sock *newsk, 4954 const struct request_sock *req) 4955 { 4956 call_void_hook(inet_csk_clone, newsk, req); 4957 } 4958 4959 /** 4960 * security_inet_conn_established() - Update sock's LSM state with connection 4961 * @sk: sock 4962 * @skb: connection packet 4963 * 4964 * Update @sock's LSM state to represent a new connection from @skb. 4965 */ 4966 void security_inet_conn_established(struct sock *sk, 4967 struct sk_buff *skb) 4968 { 4969 call_void_hook(inet_conn_established, sk, skb); 4970 } 4971 EXPORT_SYMBOL(security_inet_conn_established); 4972 4973 /** 4974 * security_secmark_relabel_packet() - Check if setting a secmark is allowed 4975 * @secid: new secmark value 4976 * 4977 * Check if the process should be allowed to relabel packets to @secid. 4978 * 4979 * Return: Returns 0 if permission is granted. 4980 */ 4981 int security_secmark_relabel_packet(u32 secid) 4982 { 4983 return call_int_hook(secmark_relabel_packet, secid); 4984 } 4985 EXPORT_SYMBOL(security_secmark_relabel_packet); 4986 4987 /** 4988 * security_secmark_refcount_inc() - Increment the secmark labeling rule count 4989 * 4990 * Tells the LSM to increment the number of secmark labeling rules loaded. 4991 */ 4992 void security_secmark_refcount_inc(void) 4993 { 4994 call_void_hook(secmark_refcount_inc); 4995 } 4996 EXPORT_SYMBOL(security_secmark_refcount_inc); 4997 4998 /** 4999 * security_secmark_refcount_dec() - Decrement the secmark labeling rule count 5000 * 5001 * Tells the LSM to decrement the number of secmark labeling rules loaded. 5002 */ 5003 void security_secmark_refcount_dec(void) 5004 { 5005 call_void_hook(secmark_refcount_dec); 5006 } 5007 EXPORT_SYMBOL(security_secmark_refcount_dec); 5008 5009 /** 5010 * security_tun_dev_alloc_security() - Allocate a LSM blob for a TUN device 5011 * @security: pointer to the LSM blob 5012 * 5013 * This hook allows a module to allocate a security structure for a TUN device, 5014 * returning the pointer in @security. 5015 * 5016 * Return: Returns a zero on success, negative values on failure. 5017 */ 5018 int security_tun_dev_alloc_security(void **security) 5019 { 5020 int rc; 5021 5022 rc = lsm_blob_alloc(security, blob_sizes.lbs_tun_dev, GFP_KERNEL); 5023 if (rc) 5024 return rc; 5025 5026 rc = call_int_hook(tun_dev_alloc_security, *security); 5027 if (rc) { 5028 kfree(*security); 5029 *security = NULL; 5030 } 5031 return rc; 5032 } 5033 EXPORT_SYMBOL(security_tun_dev_alloc_security); 5034 5035 /** 5036 * security_tun_dev_free_security() - Free a TUN device LSM blob 5037 * @security: LSM blob 5038 * 5039 * This hook allows a module to free the security structure for a TUN device. 5040 */ 5041 void security_tun_dev_free_security(void *security) 5042 { 5043 kfree(security); 5044 } 5045 EXPORT_SYMBOL(security_tun_dev_free_security); 5046 5047 /** 5048 * security_tun_dev_create() - Check if creating a TUN device is allowed 5049 * 5050 * Check permissions prior to creating a new TUN device. 5051 * 5052 * Return: Returns 0 if permission is granted. 5053 */ 5054 int security_tun_dev_create(void) 5055 { 5056 return call_int_hook(tun_dev_create); 5057 } 5058 EXPORT_SYMBOL(security_tun_dev_create); 5059 5060 /** 5061 * security_tun_dev_attach_queue() - Check if attaching a TUN queue is allowed 5062 * @security: TUN device LSM blob 5063 * 5064 * Check permissions prior to attaching to a TUN device queue. 5065 * 5066 * Return: Returns 0 if permission is granted. 5067 */ 5068 int security_tun_dev_attach_queue(void *security) 5069 { 5070 return call_int_hook(tun_dev_attach_queue, security); 5071 } 5072 EXPORT_SYMBOL(security_tun_dev_attach_queue); 5073 5074 /** 5075 * security_tun_dev_attach() - Update TUN device LSM state on attach 5076 * @sk: associated sock 5077 * @security: TUN device LSM blob 5078 * 5079 * This hook can be used by the module to update any security state associated 5080 * with the TUN device's sock structure. 5081 * 5082 * Return: Returns 0 if permission is granted. 5083 */ 5084 int security_tun_dev_attach(struct sock *sk, void *security) 5085 { 5086 return call_int_hook(tun_dev_attach, sk, security); 5087 } 5088 EXPORT_SYMBOL(security_tun_dev_attach); 5089 5090 /** 5091 * security_tun_dev_open() - Update TUN device LSM state on open 5092 * @security: TUN device LSM blob 5093 * 5094 * This hook can be used by the module to update any security state associated 5095 * with the TUN device's security structure. 5096 * 5097 * Return: Returns 0 if permission is granted. 5098 */ 5099 int security_tun_dev_open(void *security) 5100 { 5101 return call_int_hook(tun_dev_open, security); 5102 } 5103 EXPORT_SYMBOL(security_tun_dev_open); 5104 5105 /** 5106 * security_sctp_assoc_request() - Update the LSM on a SCTP association req 5107 * @asoc: SCTP association 5108 * @skb: packet requesting the association 5109 * 5110 * Passes the @asoc and @chunk->skb of the association INIT packet to the LSM. 5111 * 5112 * Return: Returns 0 on success, error on failure. 5113 */ 5114 int security_sctp_assoc_request(struct sctp_association *asoc, 5115 struct sk_buff *skb) 5116 { 5117 return call_int_hook(sctp_assoc_request, asoc, skb); 5118 } 5119 EXPORT_SYMBOL(security_sctp_assoc_request); 5120 5121 /** 5122 * security_sctp_bind_connect() - Validate a list of addrs for a SCTP option 5123 * @sk: socket 5124 * @optname: SCTP option to validate 5125 * @address: list of IP addresses to validate 5126 * @addrlen: length of the address list 5127 * 5128 * Validiate permissions required for each address associated with sock @sk. 5129 * Depending on @optname, the addresses will be treated as either a connect or 5130 * bind service. The @addrlen is calculated on each IPv4 and IPv6 address using 5131 * sizeof(struct sockaddr_in) or sizeof(struct sockaddr_in6). 5132 * 5133 * Return: Returns 0 on success, error on failure. 5134 */ 5135 int security_sctp_bind_connect(struct sock *sk, int optname, 5136 struct sockaddr *address, int addrlen) 5137 { 5138 return call_int_hook(sctp_bind_connect, sk, optname, address, addrlen); 5139 } 5140 EXPORT_SYMBOL(security_sctp_bind_connect); 5141 5142 /** 5143 * security_sctp_sk_clone() - Clone a SCTP sock's LSM state 5144 * @asoc: SCTP association 5145 * @sk: original sock 5146 * @newsk: target sock 5147 * 5148 * Called whenever a new socket is created by accept(2) (i.e. a TCP style 5149 * socket) or when a socket is 'peeled off' e.g userspace calls 5150 * sctp_peeloff(3). 5151 */ 5152 void security_sctp_sk_clone(struct sctp_association *asoc, struct sock *sk, 5153 struct sock *newsk) 5154 { 5155 call_void_hook(sctp_sk_clone, asoc, sk, newsk); 5156 } 5157 EXPORT_SYMBOL(security_sctp_sk_clone); 5158 5159 /** 5160 * security_sctp_assoc_established() - Update LSM state when assoc established 5161 * @asoc: SCTP association 5162 * @skb: packet establishing the association 5163 * 5164 * Passes the @asoc and @chunk->skb of the association COOKIE_ACK packet to the 5165 * security module. 5166 * 5167 * Return: Returns 0 if permission is granted. 5168 */ 5169 int security_sctp_assoc_established(struct sctp_association *asoc, 5170 struct sk_buff *skb) 5171 { 5172 return call_int_hook(sctp_assoc_established, asoc, skb); 5173 } 5174 EXPORT_SYMBOL(security_sctp_assoc_established); 5175 5176 /** 5177 * security_mptcp_add_subflow() - Inherit the LSM label from the MPTCP socket 5178 * @sk: the owning MPTCP socket 5179 * @ssk: the new subflow 5180 * 5181 * Update the labeling for the given MPTCP subflow, to match the one of the 5182 * owning MPTCP socket. This hook has to be called after the socket creation and 5183 * initialization via the security_socket_create() and 5184 * security_socket_post_create() LSM hooks. 5185 * 5186 * Return: Returns 0 on success or a negative error code on failure. 5187 */ 5188 int security_mptcp_add_subflow(struct sock *sk, struct sock *ssk) 5189 { 5190 return call_int_hook(mptcp_add_subflow, sk, ssk); 5191 } 5192 5193 #endif /* CONFIG_SECURITY_NETWORK */ 5194 5195 #ifdef CONFIG_SECURITY_INFINIBAND 5196 /** 5197 * security_ib_pkey_access() - Check if access to an IB pkey is allowed 5198 * @sec: LSM blob 5199 * @subnet_prefix: subnet prefix of the port 5200 * @pkey: IB pkey 5201 * 5202 * Check permission to access a pkey when modifying a QP. 5203 * 5204 * Return: Returns 0 if permission is granted. 5205 */ 5206 int security_ib_pkey_access(void *sec, u64 subnet_prefix, u16 pkey) 5207 { 5208 return call_int_hook(ib_pkey_access, sec, subnet_prefix, pkey); 5209 } 5210 EXPORT_SYMBOL(security_ib_pkey_access); 5211 5212 /** 5213 * security_ib_endport_manage_subnet() - Check if SMPs traffic is allowed 5214 * @sec: LSM blob 5215 * @dev_name: IB device name 5216 * @port_num: port number 5217 * 5218 * Check permissions to send and receive SMPs on a end port. 5219 * 5220 * Return: Returns 0 if permission is granted. 5221 */ 5222 int security_ib_endport_manage_subnet(void *sec, 5223 const char *dev_name, u8 port_num) 5224 { 5225 return call_int_hook(ib_endport_manage_subnet, sec, dev_name, port_num); 5226 } 5227 EXPORT_SYMBOL(security_ib_endport_manage_subnet); 5228 5229 /** 5230 * security_ib_alloc_security() - Allocate an Infiniband LSM blob 5231 * @sec: LSM blob 5232 * 5233 * Allocate a security structure for Infiniband objects. 5234 * 5235 * Return: Returns 0 on success, non-zero on failure. 5236 */ 5237 int security_ib_alloc_security(void **sec) 5238 { 5239 int rc; 5240 5241 rc = lsm_blob_alloc(sec, blob_sizes.lbs_ib, GFP_KERNEL); 5242 if (rc) 5243 return rc; 5244 5245 rc = call_int_hook(ib_alloc_security, *sec); 5246 if (rc) { 5247 kfree(*sec); 5248 *sec = NULL; 5249 } 5250 return rc; 5251 } 5252 EXPORT_SYMBOL(security_ib_alloc_security); 5253 5254 /** 5255 * security_ib_free_security() - Free an Infiniband LSM blob 5256 * @sec: LSM blob 5257 * 5258 * Deallocate an Infiniband security structure. 5259 */ 5260 void security_ib_free_security(void *sec) 5261 { 5262 kfree(sec); 5263 } 5264 EXPORT_SYMBOL(security_ib_free_security); 5265 #endif /* CONFIG_SECURITY_INFINIBAND */ 5266 5267 #ifdef CONFIG_SECURITY_NETWORK_XFRM 5268 /** 5269 * security_xfrm_policy_alloc() - Allocate a xfrm policy LSM blob 5270 * @ctxp: xfrm security context being added to the SPD 5271 * @sec_ctx: security label provided by userspace 5272 * @gfp: gfp flags 5273 * 5274 * Allocate a security structure to the xp->security field; the security field 5275 * is initialized to NULL when the xfrm_policy is allocated. 5276 * 5277 * Return: Return 0 if operation was successful. 5278 */ 5279 int security_xfrm_policy_alloc(struct xfrm_sec_ctx **ctxp, 5280 struct xfrm_user_sec_ctx *sec_ctx, 5281 gfp_t gfp) 5282 { 5283 return call_int_hook(xfrm_policy_alloc_security, ctxp, sec_ctx, gfp); 5284 } 5285 EXPORT_SYMBOL(security_xfrm_policy_alloc); 5286 5287 /** 5288 * security_xfrm_policy_clone() - Clone xfrm policy LSM state 5289 * @old_ctx: xfrm security context 5290 * @new_ctxp: target xfrm security context 5291 * 5292 * Allocate a security structure in new_ctxp that contains the information from 5293 * the old_ctx structure. 5294 * 5295 * Return: Return 0 if operation was successful. 5296 */ 5297 int security_xfrm_policy_clone(struct xfrm_sec_ctx *old_ctx, 5298 struct xfrm_sec_ctx **new_ctxp) 5299 { 5300 return call_int_hook(xfrm_policy_clone_security, old_ctx, new_ctxp); 5301 } 5302 5303 /** 5304 * security_xfrm_policy_free() - Free a xfrm security context 5305 * @ctx: xfrm security context 5306 * 5307 * Free LSM resources associated with @ctx. 5308 */ 5309 void security_xfrm_policy_free(struct xfrm_sec_ctx *ctx) 5310 { 5311 call_void_hook(xfrm_policy_free_security, ctx); 5312 } 5313 EXPORT_SYMBOL(security_xfrm_policy_free); 5314 5315 /** 5316 * security_xfrm_policy_delete() - Check if deleting a xfrm policy is allowed 5317 * @ctx: xfrm security context 5318 * 5319 * Authorize deletion of a SPD entry. 5320 * 5321 * Return: Returns 0 if permission is granted. 5322 */ 5323 int security_xfrm_policy_delete(struct xfrm_sec_ctx *ctx) 5324 { 5325 return call_int_hook(xfrm_policy_delete_security, ctx); 5326 } 5327 5328 /** 5329 * security_xfrm_state_alloc() - Allocate a xfrm state LSM blob 5330 * @x: xfrm state being added to the SAD 5331 * @sec_ctx: security label provided by userspace 5332 * 5333 * Allocate a security structure to the @x->security field; the security field 5334 * is initialized to NULL when the xfrm_state is allocated. Set the context to 5335 * correspond to @sec_ctx. 5336 * 5337 * Return: Return 0 if operation was successful. 5338 */ 5339 int security_xfrm_state_alloc(struct xfrm_state *x, 5340 struct xfrm_user_sec_ctx *sec_ctx) 5341 { 5342 return call_int_hook(xfrm_state_alloc, x, sec_ctx); 5343 } 5344 EXPORT_SYMBOL(security_xfrm_state_alloc); 5345 5346 /** 5347 * security_xfrm_state_alloc_acquire() - Allocate a xfrm state LSM blob 5348 * @x: xfrm state being added to the SAD 5349 * @polsec: associated policy's security context 5350 * @secid: secid from the flow 5351 * 5352 * Allocate a security structure to the x->security field; the security field 5353 * is initialized to NULL when the xfrm_state is allocated. Set the context to 5354 * correspond to secid. 5355 * 5356 * Return: Returns 0 if operation was successful. 5357 */ 5358 int security_xfrm_state_alloc_acquire(struct xfrm_state *x, 5359 struct xfrm_sec_ctx *polsec, u32 secid) 5360 { 5361 return call_int_hook(xfrm_state_alloc_acquire, x, polsec, secid); 5362 } 5363 5364 /** 5365 * security_xfrm_state_delete() - Check if deleting a xfrm state is allowed 5366 * @x: xfrm state 5367 * 5368 * Authorize deletion of x->security. 5369 * 5370 * Return: Returns 0 if permission is granted. 5371 */ 5372 int security_xfrm_state_delete(struct xfrm_state *x) 5373 { 5374 return call_int_hook(xfrm_state_delete_security, x); 5375 } 5376 EXPORT_SYMBOL(security_xfrm_state_delete); 5377 5378 /** 5379 * security_xfrm_state_free() - Free a xfrm state 5380 * @x: xfrm state 5381 * 5382 * Deallocate x->security. 5383 */ 5384 void security_xfrm_state_free(struct xfrm_state *x) 5385 { 5386 call_void_hook(xfrm_state_free_security, x); 5387 } 5388 5389 /** 5390 * security_xfrm_policy_lookup() - Check if using a xfrm policy is allowed 5391 * @ctx: target xfrm security context 5392 * @fl_secid: flow secid used to authorize access 5393 * 5394 * Check permission when a flow selects a xfrm_policy for processing XFRMs on a 5395 * packet. The hook is called when selecting either a per-socket policy or a 5396 * generic xfrm policy. 5397 * 5398 * Return: Return 0 if permission is granted, -ESRCH otherwise, or -errno on 5399 * other errors. 5400 */ 5401 int security_xfrm_policy_lookup(struct xfrm_sec_ctx *ctx, u32 fl_secid) 5402 { 5403 return call_int_hook(xfrm_policy_lookup, ctx, fl_secid); 5404 } 5405 5406 /** 5407 * security_xfrm_state_pol_flow_match() - Check for a xfrm match 5408 * @x: xfrm state to match 5409 * @xp: xfrm policy to check for a match 5410 * @flic: flow to check for a match. 5411 * 5412 * Check @xp and @flic for a match with @x. 5413 * 5414 * Return: Returns 1 if there is a match. 5415 */ 5416 int security_xfrm_state_pol_flow_match(struct xfrm_state *x, 5417 struct xfrm_policy *xp, 5418 const struct flowi_common *flic) 5419 { 5420 struct lsm_static_call *scall; 5421 int rc = LSM_RET_DEFAULT(xfrm_state_pol_flow_match); 5422 5423 /* 5424 * Since this function is expected to return 0 or 1, the judgment 5425 * becomes difficult if multiple LSMs supply this call. Fortunately, 5426 * we can use the first LSM's judgment because currently only SELinux 5427 * supplies this call. 5428 * 5429 * For speed optimization, we explicitly break the loop rather than 5430 * using the macro 5431 */ 5432 lsm_for_each_hook(scall, xfrm_state_pol_flow_match) { 5433 rc = scall->hl->hook.xfrm_state_pol_flow_match(x, xp, flic); 5434 break; 5435 } 5436 return rc; 5437 } 5438 5439 /** 5440 * security_xfrm_decode_session() - Determine the xfrm secid for a packet 5441 * @skb: xfrm packet 5442 * @secid: secid 5443 * 5444 * Decode the packet in @skb and return the security label in @secid. 5445 * 5446 * Return: Return 0 if all xfrms used have the same secid. 5447 */ 5448 int security_xfrm_decode_session(struct sk_buff *skb, u32 *secid) 5449 { 5450 return call_int_hook(xfrm_decode_session, skb, secid, 1); 5451 } 5452 5453 void security_skb_classify_flow(struct sk_buff *skb, struct flowi_common *flic) 5454 { 5455 int rc = call_int_hook(xfrm_decode_session, skb, &flic->flowic_secid, 5456 0); 5457 5458 BUG_ON(rc); 5459 } 5460 EXPORT_SYMBOL(security_skb_classify_flow); 5461 #endif /* CONFIG_SECURITY_NETWORK_XFRM */ 5462 5463 #ifdef CONFIG_KEYS 5464 /** 5465 * security_key_alloc() - Allocate and initialize a kernel key LSM blob 5466 * @key: key 5467 * @cred: credentials 5468 * @flags: allocation flags 5469 * 5470 * Permit allocation of a key and assign security data. Note that key does not 5471 * have a serial number assigned at this point. 5472 * 5473 * Return: Return 0 if permission is granted, -ve error otherwise. 5474 */ 5475 int security_key_alloc(struct key *key, const struct cred *cred, 5476 unsigned long flags) 5477 { 5478 int rc = lsm_key_alloc(key); 5479 5480 if (unlikely(rc)) 5481 return rc; 5482 rc = call_int_hook(key_alloc, key, cred, flags); 5483 if (unlikely(rc)) 5484 security_key_free(key); 5485 return rc; 5486 } 5487 5488 /** 5489 * security_key_free() - Free a kernel key LSM blob 5490 * @key: key 5491 * 5492 * Notification of destruction; free security data. 5493 */ 5494 void security_key_free(struct key *key) 5495 { 5496 kfree(key->security); 5497 key->security = NULL; 5498 } 5499 5500 /** 5501 * security_key_permission() - Check if a kernel key operation is allowed 5502 * @key_ref: key reference 5503 * @cred: credentials of actor requesting access 5504 * @need_perm: requested permissions 5505 * 5506 * See whether a specific operational right is granted to a process on a key. 5507 * 5508 * Return: Return 0 if permission is granted, -ve error otherwise. 5509 */ 5510 int security_key_permission(key_ref_t key_ref, const struct cred *cred, 5511 enum key_need_perm need_perm) 5512 { 5513 return call_int_hook(key_permission, key_ref, cred, need_perm); 5514 } 5515 5516 /** 5517 * security_key_getsecurity() - Get the key's security label 5518 * @key: key 5519 * @buffer: security label buffer 5520 * 5521 * Get a textual representation of the security context attached to a key for 5522 * the purposes of honouring KEYCTL_GETSECURITY. This function allocates the 5523 * storage for the NUL-terminated string and the caller should free it. 5524 * 5525 * Return: Returns the length of @buffer (including terminating NUL) or -ve if 5526 * an error occurs. May also return 0 (and a NULL buffer pointer) if 5527 * there is no security label assigned to the key. 5528 */ 5529 int security_key_getsecurity(struct key *key, char **buffer) 5530 { 5531 *buffer = NULL; 5532 return call_int_hook(key_getsecurity, key, buffer); 5533 } 5534 5535 /** 5536 * security_key_post_create_or_update() - Notification of key create or update 5537 * @keyring: keyring to which the key is linked to 5538 * @key: created or updated key 5539 * @payload: data used to instantiate or update the key 5540 * @payload_len: length of payload 5541 * @flags: key flags 5542 * @create: flag indicating whether the key was created or updated 5543 * 5544 * Notify the caller of a key creation or update. 5545 */ 5546 void security_key_post_create_or_update(struct key *keyring, struct key *key, 5547 const void *payload, size_t payload_len, 5548 unsigned long flags, bool create) 5549 { 5550 call_void_hook(key_post_create_or_update, keyring, key, payload, 5551 payload_len, flags, create); 5552 } 5553 #endif /* CONFIG_KEYS */ 5554 5555 #ifdef CONFIG_AUDIT 5556 /** 5557 * security_audit_rule_init() - Allocate and init an LSM audit rule struct 5558 * @field: audit action 5559 * @op: rule operator 5560 * @rulestr: rule context 5561 * @lsmrule: receive buffer for audit rule struct 5562 * @gfp: GFP flag used for kmalloc 5563 * 5564 * Allocate and initialize an LSM audit rule structure. 5565 * 5566 * Return: Return 0 if @lsmrule has been successfully set, -EINVAL in case of 5567 * an invalid rule. 5568 */ 5569 int security_audit_rule_init(u32 field, u32 op, char *rulestr, void **lsmrule, 5570 gfp_t gfp) 5571 { 5572 return call_int_hook(audit_rule_init, field, op, rulestr, lsmrule, gfp); 5573 } 5574 5575 /** 5576 * security_audit_rule_known() - Check if an audit rule contains LSM fields 5577 * @krule: audit rule 5578 * 5579 * Specifies whether given @krule contains any fields related to the current 5580 * LSM. 5581 * 5582 * Return: Returns 1 in case of relation found, 0 otherwise. 5583 */ 5584 int security_audit_rule_known(struct audit_krule *krule) 5585 { 5586 return call_int_hook(audit_rule_known, krule); 5587 } 5588 5589 /** 5590 * security_audit_rule_free() - Free an LSM audit rule struct 5591 * @lsmrule: audit rule struct 5592 * 5593 * Deallocate the LSM audit rule structure previously allocated by 5594 * audit_rule_init(). 5595 */ 5596 void security_audit_rule_free(void *lsmrule) 5597 { 5598 call_void_hook(audit_rule_free, lsmrule); 5599 } 5600 5601 /** 5602 * security_audit_rule_match() - Check if a label matches an audit rule 5603 * @prop: security label 5604 * @field: LSM audit field 5605 * @op: matching operator 5606 * @lsmrule: audit rule 5607 * 5608 * Determine if given @secid matches a rule previously approved by 5609 * security_audit_rule_known(). 5610 * 5611 * Return: Returns 1 if secid matches the rule, 0 if it does not, -ERRNO on 5612 * failure. 5613 */ 5614 int security_audit_rule_match(struct lsm_prop *prop, u32 field, u32 op, 5615 void *lsmrule) 5616 { 5617 return call_int_hook(audit_rule_match, prop, field, op, lsmrule); 5618 } 5619 #endif /* CONFIG_AUDIT */ 5620 5621 #ifdef CONFIG_BPF_SYSCALL 5622 /** 5623 * security_bpf() - Check if the bpf syscall operation is allowed 5624 * @cmd: command 5625 * @attr: bpf attribute 5626 * @size: size 5627 * 5628 * Do a initial check for all bpf syscalls after the attribute is copied into 5629 * the kernel. The actual security module can implement their own rules to 5630 * check the specific cmd they need. 5631 * 5632 * Return: Returns 0 if permission is granted. 5633 */ 5634 int security_bpf(int cmd, union bpf_attr *attr, unsigned int size) 5635 { 5636 return call_int_hook(bpf, cmd, attr, size); 5637 } 5638 5639 /** 5640 * security_bpf_map() - Check if access to a bpf map is allowed 5641 * @map: bpf map 5642 * @fmode: mode 5643 * 5644 * Do a check when the kernel generates and returns a file descriptor for eBPF 5645 * maps. 5646 * 5647 * Return: Returns 0 if permission is granted. 5648 */ 5649 int security_bpf_map(struct bpf_map *map, fmode_t fmode) 5650 { 5651 return call_int_hook(bpf_map, map, fmode); 5652 } 5653 5654 /** 5655 * security_bpf_prog() - Check if access to a bpf program is allowed 5656 * @prog: bpf program 5657 * 5658 * Do a check when the kernel generates and returns a file descriptor for eBPF 5659 * programs. 5660 * 5661 * Return: Returns 0 if permission is granted. 5662 */ 5663 int security_bpf_prog(struct bpf_prog *prog) 5664 { 5665 return call_int_hook(bpf_prog, prog); 5666 } 5667 5668 /** 5669 * security_bpf_map_create() - Check if BPF map creation is allowed 5670 * @map: BPF map object 5671 * @attr: BPF syscall attributes used to create BPF map 5672 * @token: BPF token used to grant user access 5673 * 5674 * Do a check when the kernel creates a new BPF map. This is also the 5675 * point where LSM blob is allocated for LSMs that need them. 5676 * 5677 * Return: Returns 0 on success, error on failure. 5678 */ 5679 int security_bpf_map_create(struct bpf_map *map, union bpf_attr *attr, 5680 struct bpf_token *token) 5681 { 5682 return call_int_hook(bpf_map_create, map, attr, token); 5683 } 5684 5685 /** 5686 * security_bpf_prog_load() - Check if loading of BPF program is allowed 5687 * @prog: BPF program object 5688 * @attr: BPF syscall attributes used to create BPF program 5689 * @token: BPF token used to grant user access to BPF subsystem 5690 * 5691 * Perform an access control check when the kernel loads a BPF program and 5692 * allocates associated BPF program object. This hook is also responsible for 5693 * allocating any required LSM state for the BPF program. 5694 * 5695 * Return: Returns 0 on success, error on failure. 5696 */ 5697 int security_bpf_prog_load(struct bpf_prog *prog, union bpf_attr *attr, 5698 struct bpf_token *token) 5699 { 5700 return call_int_hook(bpf_prog_load, prog, attr, token); 5701 } 5702 5703 /** 5704 * security_bpf_token_create() - Check if creating of BPF token is allowed 5705 * @token: BPF token object 5706 * @attr: BPF syscall attributes used to create BPF token 5707 * @path: path pointing to BPF FS mount point from which BPF token is created 5708 * 5709 * Do a check when the kernel instantiates a new BPF token object from BPF FS 5710 * instance. This is also the point where LSM blob can be allocated for LSMs. 5711 * 5712 * Return: Returns 0 on success, error on failure. 5713 */ 5714 int security_bpf_token_create(struct bpf_token *token, union bpf_attr *attr, 5715 const struct path *path) 5716 { 5717 return call_int_hook(bpf_token_create, token, attr, path); 5718 } 5719 5720 /** 5721 * security_bpf_token_cmd() - Check if BPF token is allowed to delegate 5722 * requested BPF syscall command 5723 * @token: BPF token object 5724 * @cmd: BPF syscall command requested to be delegated by BPF token 5725 * 5726 * Do a check when the kernel decides whether provided BPF token should allow 5727 * delegation of requested BPF syscall command. 5728 * 5729 * Return: Returns 0 on success, error on failure. 5730 */ 5731 int security_bpf_token_cmd(const struct bpf_token *token, enum bpf_cmd cmd) 5732 { 5733 return call_int_hook(bpf_token_cmd, token, cmd); 5734 } 5735 5736 /** 5737 * security_bpf_token_capable() - Check if BPF token is allowed to delegate 5738 * requested BPF-related capability 5739 * @token: BPF token object 5740 * @cap: capabilities requested to be delegated by BPF token 5741 * 5742 * Do a check when the kernel decides whether provided BPF token should allow 5743 * delegation of requested BPF-related capabilities. 5744 * 5745 * Return: Returns 0 on success, error on failure. 5746 */ 5747 int security_bpf_token_capable(const struct bpf_token *token, int cap) 5748 { 5749 return call_int_hook(bpf_token_capable, token, cap); 5750 } 5751 5752 /** 5753 * security_bpf_map_free() - Free a bpf map's LSM blob 5754 * @map: bpf map 5755 * 5756 * Clean up the security information stored inside bpf map. 5757 */ 5758 void security_bpf_map_free(struct bpf_map *map) 5759 { 5760 call_void_hook(bpf_map_free, map); 5761 } 5762 5763 /** 5764 * security_bpf_prog_free() - Free a BPF program's LSM blob 5765 * @prog: BPF program struct 5766 * 5767 * Clean up the security information stored inside BPF program. 5768 */ 5769 void security_bpf_prog_free(struct bpf_prog *prog) 5770 { 5771 call_void_hook(bpf_prog_free, prog); 5772 } 5773 5774 /** 5775 * security_bpf_token_free() - Free a BPF token's LSM blob 5776 * @token: BPF token struct 5777 * 5778 * Clean up the security information stored inside BPF token. 5779 */ 5780 void security_bpf_token_free(struct bpf_token *token) 5781 { 5782 call_void_hook(bpf_token_free, token); 5783 } 5784 #endif /* CONFIG_BPF_SYSCALL */ 5785 5786 /** 5787 * security_locked_down() - Check if a kernel feature is allowed 5788 * @what: requested kernel feature 5789 * 5790 * Determine whether a kernel feature that potentially enables arbitrary code 5791 * execution in kernel space should be permitted. 5792 * 5793 * Return: Returns 0 if permission is granted. 5794 */ 5795 int security_locked_down(enum lockdown_reason what) 5796 { 5797 return call_int_hook(locked_down, what); 5798 } 5799 EXPORT_SYMBOL(security_locked_down); 5800 5801 /** 5802 * security_bdev_alloc() - Allocate a block device LSM blob 5803 * @bdev: block device 5804 * 5805 * Allocate and attach a security structure to @bdev->bd_security. The 5806 * security field is initialized to NULL when the bdev structure is 5807 * allocated. 5808 * 5809 * Return: Return 0 if operation was successful. 5810 */ 5811 int security_bdev_alloc(struct block_device *bdev) 5812 { 5813 int rc = 0; 5814 5815 rc = lsm_bdev_alloc(bdev); 5816 if (unlikely(rc)) 5817 return rc; 5818 5819 rc = call_int_hook(bdev_alloc_security, bdev); 5820 if (unlikely(rc)) 5821 security_bdev_free(bdev); 5822 5823 return rc; 5824 } 5825 EXPORT_SYMBOL(security_bdev_alloc); 5826 5827 /** 5828 * security_bdev_free() - Free a block device's LSM blob 5829 * @bdev: block device 5830 * 5831 * Deallocate the bdev security structure and set @bdev->bd_security to NULL. 5832 */ 5833 void security_bdev_free(struct block_device *bdev) 5834 { 5835 if (!bdev->bd_security) 5836 return; 5837 5838 call_void_hook(bdev_free_security, bdev); 5839 5840 kfree(bdev->bd_security); 5841 bdev->bd_security = NULL; 5842 } 5843 EXPORT_SYMBOL(security_bdev_free); 5844 5845 /** 5846 * security_bdev_setintegrity() - Set the device's integrity data 5847 * @bdev: block device 5848 * @type: type of integrity, e.g. hash digest, signature, etc 5849 * @value: the integrity value 5850 * @size: size of the integrity value 5851 * 5852 * Register a verified integrity measurement of a bdev with LSMs. 5853 * LSMs should free the previously saved data if @value is NULL. 5854 * Please note that the new hook should be invoked every time the security 5855 * information is updated to keep these data current. For example, in dm-verity, 5856 * if the mapping table is reloaded and configured to use a different dm-verity 5857 * target with a new roothash and signing information, the previously stored 5858 * data in the LSM blob will become obsolete. It is crucial to re-invoke the 5859 * hook to refresh these data and ensure they are up to date. This necessity 5860 * arises from the design of device-mapper, where a device-mapper device is 5861 * first created, and then targets are subsequently loaded into it. These 5862 * targets can be modified multiple times during the device's lifetime. 5863 * Therefore, while the LSM blob is allocated during the creation of the block 5864 * device, its actual contents are not initialized at this stage and can change 5865 * substantially over time. This includes alterations from data that the LSMs 5866 * 'trusts' to those they do not, making it essential to handle these changes 5867 * correctly. Failure to address this dynamic aspect could potentially allow 5868 * for bypassing LSM checks. 5869 * 5870 * Return: Returns 0 on success, negative values on failure. 5871 */ 5872 int security_bdev_setintegrity(struct block_device *bdev, 5873 enum lsm_integrity_type type, const void *value, 5874 size_t size) 5875 { 5876 return call_int_hook(bdev_setintegrity, bdev, type, value, size); 5877 } 5878 EXPORT_SYMBOL(security_bdev_setintegrity); 5879 5880 #ifdef CONFIG_PERF_EVENTS 5881 /** 5882 * security_perf_event_open() - Check if a perf event open is allowed 5883 * @attr: perf event attribute 5884 * @type: type of event 5885 * 5886 * Check whether the @type of perf_event_open syscall is allowed. 5887 * 5888 * Return: Returns 0 if permission is granted. 5889 */ 5890 int security_perf_event_open(struct perf_event_attr *attr, int type) 5891 { 5892 return call_int_hook(perf_event_open, attr, type); 5893 } 5894 5895 /** 5896 * security_perf_event_alloc() - Allocate a perf event LSM blob 5897 * @event: perf event 5898 * 5899 * Allocate and save perf_event security info. 5900 * 5901 * Return: Returns 0 on success, error on failure. 5902 */ 5903 int security_perf_event_alloc(struct perf_event *event) 5904 { 5905 int rc; 5906 5907 rc = lsm_blob_alloc(&event->security, blob_sizes.lbs_perf_event, 5908 GFP_KERNEL); 5909 if (rc) 5910 return rc; 5911 5912 rc = call_int_hook(perf_event_alloc, event); 5913 if (rc) { 5914 kfree(event->security); 5915 event->security = NULL; 5916 } 5917 return rc; 5918 } 5919 5920 /** 5921 * security_perf_event_free() - Free a perf event LSM blob 5922 * @event: perf event 5923 * 5924 * Release (free) perf_event security info. 5925 */ 5926 void security_perf_event_free(struct perf_event *event) 5927 { 5928 kfree(event->security); 5929 event->security = NULL; 5930 } 5931 5932 /** 5933 * security_perf_event_read() - Check if reading a perf event label is allowed 5934 * @event: perf event 5935 * 5936 * Read perf_event security info if allowed. 5937 * 5938 * Return: Returns 0 if permission is granted. 5939 */ 5940 int security_perf_event_read(struct perf_event *event) 5941 { 5942 return call_int_hook(perf_event_read, event); 5943 } 5944 5945 /** 5946 * security_perf_event_write() - Check if writing a perf event label is allowed 5947 * @event: perf event 5948 * 5949 * Write perf_event security info if allowed. 5950 * 5951 * Return: Returns 0 if permission is granted. 5952 */ 5953 int security_perf_event_write(struct perf_event *event) 5954 { 5955 return call_int_hook(perf_event_write, event); 5956 } 5957 #endif /* CONFIG_PERF_EVENTS */ 5958 5959 #ifdef CONFIG_IO_URING 5960 /** 5961 * security_uring_override_creds() - Check if overriding creds is allowed 5962 * @new: new credentials 5963 * 5964 * Check if the current task, executing an io_uring operation, is allowed to 5965 * override it's credentials with @new. 5966 * 5967 * Return: Returns 0 if permission is granted. 5968 */ 5969 int security_uring_override_creds(const struct cred *new) 5970 { 5971 return call_int_hook(uring_override_creds, new); 5972 } 5973 5974 /** 5975 * security_uring_sqpoll() - Check if IORING_SETUP_SQPOLL is allowed 5976 * 5977 * Check whether the current task is allowed to spawn a io_uring polling thread 5978 * (IORING_SETUP_SQPOLL). 5979 * 5980 * Return: Returns 0 if permission is granted. 5981 */ 5982 int security_uring_sqpoll(void) 5983 { 5984 return call_int_hook(uring_sqpoll); 5985 } 5986 5987 /** 5988 * security_uring_cmd() - Check if a io_uring passthrough command is allowed 5989 * @ioucmd: command 5990 * 5991 * Check whether the file_operations uring_cmd is allowed to run. 5992 * 5993 * Return: Returns 0 if permission is granted. 5994 */ 5995 int security_uring_cmd(struct io_uring_cmd *ioucmd) 5996 { 5997 return call_int_hook(uring_cmd, ioucmd); 5998 } 5999 #endif /* CONFIG_IO_URING */ 6000 6001 /** 6002 * security_initramfs_populated() - Notify LSMs that initramfs has been loaded 6003 * 6004 * Tells the LSMs the initramfs has been unpacked into the rootfs. 6005 */ 6006 void security_initramfs_populated(void) 6007 { 6008 call_void_hook(initramfs_populated); 6009 } 6010