1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * Security plug functions 4 * 5 * Copyright (C) 2001 WireX Communications, Inc <chris@wirex.com> 6 * Copyright (C) 2001-2002 Greg Kroah-Hartman <greg@kroah.com> 7 * Copyright (C) 2001 Networks Associates Technology, Inc <ssmalley@nai.com> 8 * Copyright (C) 2016 Mellanox Technologies 9 * Copyright (C) 2023 Microsoft Corporation <paul@paul-moore.com> 10 */ 11 12 #define pr_fmt(fmt) "LSM: " fmt 13 14 #include <linux/bpf.h> 15 #include <linux/capability.h> 16 #include <linux/dcache.h> 17 #include <linux/export.h> 18 #include <linux/init.h> 19 #include <linux/kernel.h> 20 #include <linux/kernel_read_file.h> 21 #include <linux/lsm_hooks.h> 22 #include <linux/fsnotify.h> 23 #include <linux/mman.h> 24 #include <linux/mount.h> 25 #include <linux/personality.h> 26 #include <linux/backing-dev.h> 27 #include <linux/string.h> 28 #include <linux/xattr.h> 29 #include <linux/msg.h> 30 #include <linux/overflow.h> 31 #include <linux/perf_event.h> 32 #include <linux/fs.h> 33 #include <net/flow.h> 34 #include <net/sock.h> 35 36 #define SECURITY_HOOK_ACTIVE_KEY(HOOK, IDX) security_hook_active_##HOOK##_##IDX 37 38 /* 39 * Identifier for the LSM static calls. 40 * HOOK is an LSM hook as defined in linux/lsm_hookdefs.h 41 * IDX is the index of the static call. 0 <= NUM < MAX_LSM_COUNT 42 */ 43 #define LSM_STATIC_CALL(HOOK, IDX) lsm_static_call_##HOOK##_##IDX 44 45 /* 46 * Call the macro M for each LSM hook MAX_LSM_COUNT times. 47 */ 48 #define LSM_LOOP_UNROLL(M, ...) \ 49 do { \ 50 UNROLL(MAX_LSM_COUNT, M, __VA_ARGS__) \ 51 } while (0) 52 53 #define LSM_DEFINE_UNROLL(M, ...) UNROLL(MAX_LSM_COUNT, M, __VA_ARGS__) 54 55 /* 56 * These are descriptions of the reasons that can be passed to the 57 * security_locked_down() LSM hook. Placing this array here allows 58 * all security modules to use the same descriptions for auditing 59 * purposes. 60 */ 61 const char *const lockdown_reasons[LOCKDOWN_CONFIDENTIALITY_MAX + 1] = { 62 [LOCKDOWN_NONE] = "none", 63 [LOCKDOWN_MODULE_SIGNATURE] = "unsigned module loading", 64 [LOCKDOWN_DEV_MEM] = "/dev/mem,kmem,port", 65 [LOCKDOWN_EFI_TEST] = "/dev/efi_test access", 66 [LOCKDOWN_KEXEC] = "kexec of unsigned images", 67 [LOCKDOWN_HIBERNATION] = "hibernation", 68 [LOCKDOWN_PCI_ACCESS] = "direct PCI access", 69 [LOCKDOWN_IOPORT] = "raw io port access", 70 [LOCKDOWN_MSR] = "raw MSR access", 71 [LOCKDOWN_ACPI_TABLES] = "modifying ACPI tables", 72 [LOCKDOWN_DEVICE_TREE] = "modifying device tree contents", 73 [LOCKDOWN_PCMCIA_CIS] = "direct PCMCIA CIS storage", 74 [LOCKDOWN_TIOCSSERIAL] = "reconfiguration of serial port IO", 75 [LOCKDOWN_MODULE_PARAMETERS] = "unsafe module parameters", 76 [LOCKDOWN_MMIOTRACE] = "unsafe mmio", 77 [LOCKDOWN_DEBUGFS] = "debugfs access", 78 [LOCKDOWN_XMON_WR] = "xmon write access", 79 [LOCKDOWN_BPF_WRITE_USER] = "use of bpf to write user RAM", 80 [LOCKDOWN_DBG_WRITE_KERNEL] = "use of kgdb/kdb to write kernel RAM", 81 [LOCKDOWN_RTAS_ERROR_INJECTION] = "RTAS error injection", 82 [LOCKDOWN_INTEGRITY_MAX] = "integrity", 83 [LOCKDOWN_KCORE] = "/proc/kcore access", 84 [LOCKDOWN_KPROBES] = "use of kprobes", 85 [LOCKDOWN_BPF_READ_KERNEL] = "use of bpf to read kernel RAM", 86 [LOCKDOWN_DBG_READ_KERNEL] = "use of kgdb/kdb to read kernel RAM", 87 [LOCKDOWN_PERF] = "unsafe use of perf", 88 [LOCKDOWN_TRACEFS] = "use of tracefs", 89 [LOCKDOWN_XMON_RW] = "xmon read and write access", 90 [LOCKDOWN_XFRM_SECRET] = "xfrm SA secret", 91 [LOCKDOWN_CONFIDENTIALITY_MAX] = "confidentiality", 92 }; 93 94 static BLOCKING_NOTIFIER_HEAD(blocking_lsm_notifier_chain); 95 96 static struct kmem_cache *lsm_file_cache; 97 static struct kmem_cache *lsm_inode_cache; 98 99 char *lsm_names; 100 static struct lsm_blob_sizes blob_sizes __ro_after_init; 101 102 /* Boot-time LSM user choice */ 103 static __initdata const char *chosen_lsm_order; 104 static __initdata const char *chosen_major_lsm; 105 106 static __initconst const char *const builtin_lsm_order = CONFIG_LSM; 107 108 /* Ordered list of LSMs to initialize. */ 109 static __initdata struct lsm_info *ordered_lsms[MAX_LSM_COUNT + 1]; 110 static __initdata struct lsm_info *exclusive; 111 112 #ifdef CONFIG_HAVE_STATIC_CALL 113 #define LSM_HOOK_TRAMP(NAME, NUM) \ 114 &STATIC_CALL_TRAMP(LSM_STATIC_CALL(NAME, NUM)) 115 #else 116 #define LSM_HOOK_TRAMP(NAME, NUM) NULL 117 #endif 118 119 /* 120 * Define static calls and static keys for each LSM hook. 121 */ 122 #define DEFINE_LSM_STATIC_CALL(NUM, NAME, RET, ...) \ 123 DEFINE_STATIC_CALL_NULL(LSM_STATIC_CALL(NAME, NUM), \ 124 *((RET(*)(__VA_ARGS__))NULL)); \ 125 DEFINE_STATIC_KEY_FALSE(SECURITY_HOOK_ACTIVE_KEY(NAME, NUM)); 126 127 #define LSM_HOOK(RET, DEFAULT, NAME, ...) \ 128 LSM_DEFINE_UNROLL(DEFINE_LSM_STATIC_CALL, NAME, RET, __VA_ARGS__) 129 #include <linux/lsm_hook_defs.h> 130 #undef LSM_HOOK 131 #undef DEFINE_LSM_STATIC_CALL 132 133 /* 134 * Initialise a table of static calls for each LSM hook. 135 * DEFINE_STATIC_CALL_NULL invocation above generates a key (STATIC_CALL_KEY) 136 * and a trampoline (STATIC_CALL_TRAMP) which are used to call 137 * __static_call_update when updating the static call. 138 * 139 * The static calls table is used by early LSMs, some architectures can fault on 140 * unaligned accesses and the fault handling code may not be ready by then. 141 * Thus, the static calls table should be aligned to avoid any unhandled faults 142 * in early init. 143 */ 144 struct lsm_static_calls_table 145 static_calls_table __ro_after_init __aligned(sizeof(u64)) = { 146 #define INIT_LSM_STATIC_CALL(NUM, NAME) \ 147 (struct lsm_static_call) { \ 148 .key = &STATIC_CALL_KEY(LSM_STATIC_CALL(NAME, NUM)), \ 149 .trampoline = LSM_HOOK_TRAMP(NAME, NUM), \ 150 .active = &SECURITY_HOOK_ACTIVE_KEY(NAME, NUM), \ 151 }, 152 #define LSM_HOOK(RET, DEFAULT, NAME, ...) \ 153 .NAME = { \ 154 LSM_DEFINE_UNROLL(INIT_LSM_STATIC_CALL, NAME) \ 155 }, 156 #include <linux/lsm_hook_defs.h> 157 #undef LSM_HOOK 158 #undef INIT_LSM_STATIC_CALL 159 }; 160 161 static __initdata bool debug; 162 #define init_debug(...) \ 163 do { \ 164 if (debug) \ 165 pr_info(__VA_ARGS__); \ 166 } while (0) 167 168 static bool __init is_enabled(struct lsm_info *lsm) 169 { 170 if (!lsm->enabled) 171 return false; 172 173 return *lsm->enabled; 174 } 175 176 /* Mark an LSM's enabled flag. */ 177 static int lsm_enabled_true __initdata = 1; 178 static int lsm_enabled_false __initdata = 0; 179 static void __init set_enabled(struct lsm_info *lsm, bool enabled) 180 { 181 /* 182 * When an LSM hasn't configured an enable variable, we can use 183 * a hard-coded location for storing the default enabled state. 184 */ 185 if (!lsm->enabled) { 186 if (enabled) 187 lsm->enabled = &lsm_enabled_true; 188 else 189 lsm->enabled = &lsm_enabled_false; 190 } else if (lsm->enabled == &lsm_enabled_true) { 191 if (!enabled) 192 lsm->enabled = &lsm_enabled_false; 193 } else if (lsm->enabled == &lsm_enabled_false) { 194 if (enabled) 195 lsm->enabled = &lsm_enabled_true; 196 } else { 197 *lsm->enabled = enabled; 198 } 199 } 200 201 /* Is an LSM already listed in the ordered LSMs list? */ 202 static bool __init exists_ordered_lsm(struct lsm_info *lsm) 203 { 204 struct lsm_info **check; 205 206 for (check = ordered_lsms; *check; check++) 207 if (*check == lsm) 208 return true; 209 210 return false; 211 } 212 213 /* Append an LSM to the list of ordered LSMs to initialize. */ 214 static int last_lsm __initdata; 215 static void __init append_ordered_lsm(struct lsm_info *lsm, const char *from) 216 { 217 /* Ignore duplicate selections. */ 218 if (exists_ordered_lsm(lsm)) 219 return; 220 221 if (WARN(last_lsm == MAX_LSM_COUNT, "%s: out of LSM static calls!?\n", from)) 222 return; 223 224 /* Enable this LSM, if it is not already set. */ 225 if (!lsm->enabled) 226 lsm->enabled = &lsm_enabled_true; 227 ordered_lsms[last_lsm++] = lsm; 228 229 init_debug("%s ordered: %s (%s)\n", from, lsm->name, 230 is_enabled(lsm) ? "enabled" : "disabled"); 231 } 232 233 /* Is an LSM allowed to be initialized? */ 234 static bool __init lsm_allowed(struct lsm_info *lsm) 235 { 236 /* Skip if the LSM is disabled. */ 237 if (!is_enabled(lsm)) 238 return false; 239 240 /* Not allowed if another exclusive LSM already initialized. */ 241 if ((lsm->flags & LSM_FLAG_EXCLUSIVE) && exclusive) { 242 init_debug("exclusive disabled: %s\n", lsm->name); 243 return false; 244 } 245 246 return true; 247 } 248 249 static void __init lsm_set_blob_size(int *need, int *lbs) 250 { 251 int offset; 252 253 if (*need <= 0) 254 return; 255 256 offset = ALIGN(*lbs, sizeof(void *)); 257 *lbs = offset + *need; 258 *need = offset; 259 } 260 261 static void __init lsm_set_blob_sizes(struct lsm_blob_sizes *needed) 262 { 263 if (!needed) 264 return; 265 266 lsm_set_blob_size(&needed->lbs_cred, &blob_sizes.lbs_cred); 267 lsm_set_blob_size(&needed->lbs_file, &blob_sizes.lbs_file); 268 lsm_set_blob_size(&needed->lbs_ib, &blob_sizes.lbs_ib); 269 /* 270 * The inode blob gets an rcu_head in addition to 271 * what the modules might need. 272 */ 273 if (needed->lbs_inode && blob_sizes.lbs_inode == 0) 274 blob_sizes.lbs_inode = sizeof(struct rcu_head); 275 lsm_set_blob_size(&needed->lbs_inode, &blob_sizes.lbs_inode); 276 lsm_set_blob_size(&needed->lbs_ipc, &blob_sizes.lbs_ipc); 277 lsm_set_blob_size(&needed->lbs_key, &blob_sizes.lbs_key); 278 lsm_set_blob_size(&needed->lbs_msg_msg, &blob_sizes.lbs_msg_msg); 279 lsm_set_blob_size(&needed->lbs_perf_event, &blob_sizes.lbs_perf_event); 280 lsm_set_blob_size(&needed->lbs_sock, &blob_sizes.lbs_sock); 281 lsm_set_blob_size(&needed->lbs_superblock, &blob_sizes.lbs_superblock); 282 lsm_set_blob_size(&needed->lbs_task, &blob_sizes.lbs_task); 283 lsm_set_blob_size(&needed->lbs_tun_dev, &blob_sizes.lbs_tun_dev); 284 lsm_set_blob_size(&needed->lbs_xattr_count, 285 &blob_sizes.lbs_xattr_count); 286 lsm_set_blob_size(&needed->lbs_bdev, &blob_sizes.lbs_bdev); 287 } 288 289 /* Prepare LSM for initialization. */ 290 static void __init prepare_lsm(struct lsm_info *lsm) 291 { 292 int enabled = lsm_allowed(lsm); 293 294 /* Record enablement (to handle any following exclusive LSMs). */ 295 set_enabled(lsm, enabled); 296 297 /* If enabled, do pre-initialization work. */ 298 if (enabled) { 299 if ((lsm->flags & LSM_FLAG_EXCLUSIVE) && !exclusive) { 300 exclusive = lsm; 301 init_debug("exclusive chosen: %s\n", lsm->name); 302 } 303 304 lsm_set_blob_sizes(lsm->blobs); 305 } 306 } 307 308 /* Initialize a given LSM, if it is enabled. */ 309 static void __init initialize_lsm(struct lsm_info *lsm) 310 { 311 if (is_enabled(lsm)) { 312 int ret; 313 314 init_debug("initializing %s\n", lsm->name); 315 ret = lsm->init(); 316 WARN(ret, "%s failed to initialize: %d\n", lsm->name, ret); 317 } 318 } 319 320 /* 321 * Current index to use while initializing the lsm id list. 322 */ 323 u32 lsm_active_cnt __ro_after_init; 324 const struct lsm_id *lsm_idlist[MAX_LSM_COUNT]; 325 326 /* Populate ordered LSMs list from comma-separated LSM name list. */ 327 static void __init ordered_lsm_parse(const char *order, const char *origin) 328 { 329 struct lsm_info *lsm; 330 char *sep, *name, *next; 331 332 /* LSM_ORDER_FIRST is always first. */ 333 for (lsm = __start_lsm_info; lsm < __end_lsm_info; lsm++) { 334 if (lsm->order == LSM_ORDER_FIRST) 335 append_ordered_lsm(lsm, " first"); 336 } 337 338 /* Process "security=", if given. */ 339 if (chosen_major_lsm) { 340 struct lsm_info *major; 341 342 /* 343 * To match the original "security=" behavior, this 344 * explicitly does NOT fallback to another Legacy Major 345 * if the selected one was separately disabled: disable 346 * all non-matching Legacy Major LSMs. 347 */ 348 for (major = __start_lsm_info; major < __end_lsm_info; 349 major++) { 350 if ((major->flags & LSM_FLAG_LEGACY_MAJOR) && 351 strcmp(major->name, chosen_major_lsm) != 0) { 352 set_enabled(major, false); 353 init_debug("security=%s disabled: %s (only one legacy major LSM)\n", 354 chosen_major_lsm, major->name); 355 } 356 } 357 } 358 359 sep = kstrdup(order, GFP_KERNEL); 360 next = sep; 361 /* Walk the list, looking for matching LSMs. */ 362 while ((name = strsep(&next, ",")) != NULL) { 363 bool found = false; 364 365 for (lsm = __start_lsm_info; lsm < __end_lsm_info; lsm++) { 366 if (strcmp(lsm->name, name) == 0) { 367 if (lsm->order == LSM_ORDER_MUTABLE) 368 append_ordered_lsm(lsm, origin); 369 found = true; 370 } 371 } 372 373 if (!found) 374 init_debug("%s ignored: %s (not built into kernel)\n", 375 origin, name); 376 } 377 378 /* Process "security=", if given. */ 379 if (chosen_major_lsm) { 380 for (lsm = __start_lsm_info; lsm < __end_lsm_info; lsm++) { 381 if (exists_ordered_lsm(lsm)) 382 continue; 383 if (strcmp(lsm->name, chosen_major_lsm) == 0) 384 append_ordered_lsm(lsm, "security="); 385 } 386 } 387 388 /* LSM_ORDER_LAST is always last. */ 389 for (lsm = __start_lsm_info; lsm < __end_lsm_info; lsm++) { 390 if (lsm->order == LSM_ORDER_LAST) 391 append_ordered_lsm(lsm, " last"); 392 } 393 394 /* Disable all LSMs not in the ordered list. */ 395 for (lsm = __start_lsm_info; lsm < __end_lsm_info; lsm++) { 396 if (exists_ordered_lsm(lsm)) 397 continue; 398 set_enabled(lsm, false); 399 init_debug("%s skipped: %s (not in requested order)\n", 400 origin, lsm->name); 401 } 402 403 kfree(sep); 404 } 405 406 static void __init lsm_static_call_init(struct security_hook_list *hl) 407 { 408 struct lsm_static_call *scall = hl->scalls; 409 int i; 410 411 for (i = 0; i < MAX_LSM_COUNT; i++) { 412 /* Update the first static call that is not used yet */ 413 if (!scall->hl) { 414 __static_call_update(scall->key, scall->trampoline, 415 hl->hook.lsm_func_addr); 416 scall->hl = hl; 417 static_branch_enable(scall->active); 418 return; 419 } 420 scall++; 421 } 422 panic("%s - Ran out of static slots.\n", __func__); 423 } 424 425 static void __init lsm_early_cred(struct cred *cred); 426 static void __init lsm_early_task(struct task_struct *task); 427 428 static int lsm_append(const char *new, char **result); 429 430 static void __init report_lsm_order(void) 431 { 432 struct lsm_info **lsm, *early; 433 int first = 0; 434 435 pr_info("initializing lsm="); 436 437 /* Report each enabled LSM name, comma separated. */ 438 for (early = __start_early_lsm_info; 439 early < __end_early_lsm_info; early++) 440 if (is_enabled(early)) 441 pr_cont("%s%s", first++ == 0 ? "" : ",", early->name); 442 for (lsm = ordered_lsms; *lsm; lsm++) 443 if (is_enabled(*lsm)) 444 pr_cont("%s%s", first++ == 0 ? "" : ",", (*lsm)->name); 445 446 pr_cont("\n"); 447 } 448 449 static void __init ordered_lsm_init(void) 450 { 451 struct lsm_info **lsm; 452 453 if (chosen_lsm_order) { 454 if (chosen_major_lsm) { 455 pr_warn("security=%s is ignored because it is superseded by lsm=%s\n", 456 chosen_major_lsm, chosen_lsm_order); 457 chosen_major_lsm = NULL; 458 } 459 ordered_lsm_parse(chosen_lsm_order, "cmdline"); 460 } else 461 ordered_lsm_parse(builtin_lsm_order, "builtin"); 462 463 for (lsm = ordered_lsms; *lsm; lsm++) 464 prepare_lsm(*lsm); 465 466 report_lsm_order(); 467 468 init_debug("cred blob size = %d\n", blob_sizes.lbs_cred); 469 init_debug("file blob size = %d\n", blob_sizes.lbs_file); 470 init_debug("ib blob size = %d\n", blob_sizes.lbs_ib); 471 init_debug("inode blob size = %d\n", blob_sizes.lbs_inode); 472 init_debug("ipc blob size = %d\n", blob_sizes.lbs_ipc); 473 #ifdef CONFIG_KEYS 474 init_debug("key blob size = %d\n", blob_sizes.lbs_key); 475 #endif /* CONFIG_KEYS */ 476 init_debug("msg_msg blob size = %d\n", blob_sizes.lbs_msg_msg); 477 init_debug("sock blob size = %d\n", blob_sizes.lbs_sock); 478 init_debug("superblock blob size = %d\n", blob_sizes.lbs_superblock); 479 init_debug("perf event blob size = %d\n", blob_sizes.lbs_perf_event); 480 init_debug("task blob size = %d\n", blob_sizes.lbs_task); 481 init_debug("tun device blob size = %d\n", blob_sizes.lbs_tun_dev); 482 init_debug("xattr slots = %d\n", blob_sizes.lbs_xattr_count); 483 init_debug("bdev blob size = %d\n", blob_sizes.lbs_bdev); 484 485 /* 486 * Create any kmem_caches needed for blobs 487 */ 488 if (blob_sizes.lbs_file) 489 lsm_file_cache = kmem_cache_create("lsm_file_cache", 490 blob_sizes.lbs_file, 0, 491 SLAB_PANIC, NULL); 492 if (blob_sizes.lbs_inode) 493 lsm_inode_cache = kmem_cache_create("lsm_inode_cache", 494 blob_sizes.lbs_inode, 0, 495 SLAB_PANIC, NULL); 496 497 lsm_early_cred((struct cred *) current->cred); 498 lsm_early_task(current); 499 for (lsm = ordered_lsms; *lsm; lsm++) 500 initialize_lsm(*lsm); 501 } 502 503 int __init early_security_init(void) 504 { 505 struct lsm_info *lsm; 506 507 for (lsm = __start_early_lsm_info; lsm < __end_early_lsm_info; lsm++) { 508 if (!lsm->enabled) 509 lsm->enabled = &lsm_enabled_true; 510 prepare_lsm(lsm); 511 initialize_lsm(lsm); 512 } 513 514 return 0; 515 } 516 517 /** 518 * security_init - initializes the security framework 519 * 520 * This should be called early in the kernel initialization sequence. 521 */ 522 int __init security_init(void) 523 { 524 struct lsm_info *lsm; 525 526 init_debug("legacy security=%s\n", chosen_major_lsm ? : " *unspecified*"); 527 init_debug(" CONFIG_LSM=%s\n", builtin_lsm_order); 528 init_debug("boot arg lsm=%s\n", chosen_lsm_order ? : " *unspecified*"); 529 530 /* 531 * Append the names of the early LSM modules now that kmalloc() is 532 * available 533 */ 534 for (lsm = __start_early_lsm_info; lsm < __end_early_lsm_info; lsm++) { 535 init_debug(" early started: %s (%s)\n", lsm->name, 536 is_enabled(lsm) ? "enabled" : "disabled"); 537 if (lsm->enabled) 538 lsm_append(lsm->name, &lsm_names); 539 } 540 541 /* Load LSMs in specified order. */ 542 ordered_lsm_init(); 543 544 return 0; 545 } 546 547 /* Save user chosen LSM */ 548 static int __init choose_major_lsm(char *str) 549 { 550 chosen_major_lsm = str; 551 return 1; 552 } 553 __setup("security=", choose_major_lsm); 554 555 /* Explicitly choose LSM initialization order. */ 556 static int __init choose_lsm_order(char *str) 557 { 558 chosen_lsm_order = str; 559 return 1; 560 } 561 __setup("lsm=", choose_lsm_order); 562 563 /* Enable LSM order debugging. */ 564 static int __init enable_debug(char *str) 565 { 566 debug = true; 567 return 1; 568 } 569 __setup("lsm.debug", enable_debug); 570 571 static bool match_last_lsm(const char *list, const char *lsm) 572 { 573 const char *last; 574 575 if (WARN_ON(!list || !lsm)) 576 return false; 577 last = strrchr(list, ','); 578 if (last) 579 /* Pass the comma, strcmp() will check for '\0' */ 580 last++; 581 else 582 last = list; 583 return !strcmp(last, lsm); 584 } 585 586 static int lsm_append(const char *new, char **result) 587 { 588 char *cp; 589 590 if (*result == NULL) { 591 *result = kstrdup(new, GFP_KERNEL); 592 if (*result == NULL) 593 return -ENOMEM; 594 } else { 595 /* Check if it is the last registered name */ 596 if (match_last_lsm(*result, new)) 597 return 0; 598 cp = kasprintf(GFP_KERNEL, "%s,%s", *result, new); 599 if (cp == NULL) 600 return -ENOMEM; 601 kfree(*result); 602 *result = cp; 603 } 604 return 0; 605 } 606 607 /** 608 * security_add_hooks - Add a modules hooks to the hook lists. 609 * @hooks: the hooks to add 610 * @count: the number of hooks to add 611 * @lsmid: the identification information for the security module 612 * 613 * Each LSM has to register its hooks with the infrastructure. 614 */ 615 void __init security_add_hooks(struct security_hook_list *hooks, int count, 616 const struct lsm_id *lsmid) 617 { 618 int i; 619 620 /* 621 * A security module may call security_add_hooks() more 622 * than once during initialization, and LSM initialization 623 * is serialized. Landlock is one such case. 624 * Look at the previous entry, if there is one, for duplication. 625 */ 626 if (lsm_active_cnt == 0 || lsm_idlist[lsm_active_cnt - 1] != lsmid) { 627 if (lsm_active_cnt >= MAX_LSM_COUNT) 628 panic("%s Too many LSMs registered.\n", __func__); 629 lsm_idlist[lsm_active_cnt++] = lsmid; 630 } 631 632 for (i = 0; i < count; i++) { 633 hooks[i].lsmid = lsmid; 634 lsm_static_call_init(&hooks[i]); 635 } 636 637 /* 638 * Don't try to append during early_security_init(), we'll come back 639 * and fix this up afterwards. 640 */ 641 if (slab_is_available()) { 642 if (lsm_append(lsmid->name, &lsm_names) < 0) 643 panic("%s - Cannot get early memory.\n", __func__); 644 } 645 } 646 647 int call_blocking_lsm_notifier(enum lsm_event event, void *data) 648 { 649 return blocking_notifier_call_chain(&blocking_lsm_notifier_chain, 650 event, data); 651 } 652 EXPORT_SYMBOL(call_blocking_lsm_notifier); 653 654 int register_blocking_lsm_notifier(struct notifier_block *nb) 655 { 656 return blocking_notifier_chain_register(&blocking_lsm_notifier_chain, 657 nb); 658 } 659 EXPORT_SYMBOL(register_blocking_lsm_notifier); 660 661 int unregister_blocking_lsm_notifier(struct notifier_block *nb) 662 { 663 return blocking_notifier_chain_unregister(&blocking_lsm_notifier_chain, 664 nb); 665 } 666 EXPORT_SYMBOL(unregister_blocking_lsm_notifier); 667 668 /** 669 * lsm_blob_alloc - allocate a composite blob 670 * @dest: the destination for the blob 671 * @size: the size of the blob 672 * @gfp: allocation type 673 * 674 * Allocate a blob for all the modules 675 * 676 * Returns 0, or -ENOMEM if memory can't be allocated. 677 */ 678 static int lsm_blob_alloc(void **dest, size_t size, gfp_t gfp) 679 { 680 if (size == 0) { 681 *dest = NULL; 682 return 0; 683 } 684 685 *dest = kzalloc(size, gfp); 686 if (*dest == NULL) 687 return -ENOMEM; 688 return 0; 689 } 690 691 /** 692 * lsm_cred_alloc - allocate a composite cred blob 693 * @cred: the cred that needs a blob 694 * @gfp: allocation type 695 * 696 * Allocate the cred blob for all the modules 697 * 698 * Returns 0, or -ENOMEM if memory can't be allocated. 699 */ 700 static int lsm_cred_alloc(struct cred *cred, gfp_t gfp) 701 { 702 return lsm_blob_alloc(&cred->security, blob_sizes.lbs_cred, gfp); 703 } 704 705 /** 706 * lsm_early_cred - during initialization allocate a composite cred blob 707 * @cred: the cred that needs a blob 708 * 709 * Allocate the cred blob for all the modules 710 */ 711 static void __init lsm_early_cred(struct cred *cred) 712 { 713 int rc = lsm_cred_alloc(cred, GFP_KERNEL); 714 715 if (rc) 716 panic("%s: Early cred alloc failed.\n", __func__); 717 } 718 719 /** 720 * lsm_file_alloc - allocate a composite file blob 721 * @file: the file that needs a blob 722 * 723 * Allocate the file blob for all the modules 724 * 725 * Returns 0, or -ENOMEM if memory can't be allocated. 726 */ 727 static int lsm_file_alloc(struct file *file) 728 { 729 if (!lsm_file_cache) { 730 file->f_security = NULL; 731 return 0; 732 } 733 734 file->f_security = kmem_cache_zalloc(lsm_file_cache, GFP_KERNEL); 735 if (file->f_security == NULL) 736 return -ENOMEM; 737 return 0; 738 } 739 740 /** 741 * lsm_inode_alloc - allocate a composite inode blob 742 * @inode: the inode that needs a blob 743 * 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) 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_NOFS); 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 * 1682 * Allocate and attach a security structure to @inode->i_security. The 1683 * i_security field is initialized to NULL when the inode structure is 1684 * allocated. 1685 * 1686 * Return: Return 0 if operation was successful. 1687 */ 1688 int security_inode_alloc(struct inode *inode) 1689 { 1690 int rc = lsm_inode_alloc(inode); 1691 1692 if (unlikely(rc)) 1693 return rc; 1694 rc = call_int_hook(inode_alloc_security, inode); 1695 if (unlikely(rc)) 1696 security_inode_free(inode); 1697 return rc; 1698 } 1699 1700 static void inode_free_by_rcu(struct rcu_head *head) 1701 { 1702 /* The rcu head is at the start of the inode blob */ 1703 call_void_hook(inode_free_security_rcu, head); 1704 kmem_cache_free(lsm_inode_cache, head); 1705 } 1706 1707 /** 1708 * security_inode_free() - Free an inode's LSM blob 1709 * @inode: the inode 1710 * 1711 * Release any LSM resources associated with @inode, although due to the 1712 * inode's RCU protections it is possible that the resources will not be 1713 * fully released until after the current RCU grace period has elapsed. 1714 * 1715 * It is important for LSMs to note that despite being present in a call to 1716 * security_inode_free(), @inode may still be referenced in a VFS path walk 1717 * and calls to security_inode_permission() may be made during, or after, 1718 * a call to security_inode_free(). For this reason the inode->i_security 1719 * field is released via a call_rcu() callback and any LSMs which need to 1720 * retain inode state for use in security_inode_permission() should only 1721 * release that state in the inode_free_security_rcu() LSM hook callback. 1722 */ 1723 void security_inode_free(struct inode *inode) 1724 { 1725 call_void_hook(inode_free_security, inode); 1726 if (!inode->i_security) 1727 return; 1728 call_rcu((struct rcu_head *)inode->i_security, inode_free_by_rcu); 1729 } 1730 1731 /** 1732 * security_dentry_init_security() - Perform dentry initialization 1733 * @dentry: the dentry to initialize 1734 * @mode: mode used to determine resource type 1735 * @name: name of the last path component 1736 * @xattr_name: name of the security/LSM xattr 1737 * @ctx: pointer to the resulting LSM context 1738 * @ctxlen: length of @ctx 1739 * 1740 * Compute a context for a dentry as the inode is not yet available since NFSv4 1741 * has no label backed by an EA anyway. It is important to note that 1742 * @xattr_name does not need to be free'd by the caller, it is a static string. 1743 * 1744 * Return: Returns 0 on success, negative values on failure. 1745 */ 1746 int security_dentry_init_security(struct dentry *dentry, int mode, 1747 const struct qstr *name, 1748 const char **xattr_name, void **ctx, 1749 u32 *ctxlen) 1750 { 1751 return call_int_hook(dentry_init_security, dentry, mode, name, 1752 xattr_name, ctx, ctxlen); 1753 } 1754 EXPORT_SYMBOL(security_dentry_init_security); 1755 1756 /** 1757 * security_dentry_create_files_as() - Perform dentry initialization 1758 * @dentry: the dentry to initialize 1759 * @mode: mode used to determine resource type 1760 * @name: name of the last path component 1761 * @old: creds to use for LSM context calculations 1762 * @new: creds to modify 1763 * 1764 * Compute a context for a dentry as the inode is not yet available and set 1765 * that context in passed in creds so that new files are created using that 1766 * context. Context is calculated using the passed in creds and not the creds 1767 * of the caller. 1768 * 1769 * Return: Returns 0 on success, error on failure. 1770 */ 1771 int security_dentry_create_files_as(struct dentry *dentry, int mode, 1772 struct qstr *name, 1773 const struct cred *old, struct cred *new) 1774 { 1775 return call_int_hook(dentry_create_files_as, dentry, mode, 1776 name, old, new); 1777 } 1778 EXPORT_SYMBOL(security_dentry_create_files_as); 1779 1780 /** 1781 * security_inode_init_security() - Initialize an inode's LSM context 1782 * @inode: the inode 1783 * @dir: parent directory 1784 * @qstr: last component of the pathname 1785 * @initxattrs: callback function to write xattrs 1786 * @fs_data: filesystem specific data 1787 * 1788 * Obtain the security attribute name suffix and value to set on a newly 1789 * created inode and set up the incore security field for the new inode. This 1790 * hook is called by the fs code as part of the inode creation transaction and 1791 * provides for atomic labeling of the inode, unlike the post_create/mkdir/... 1792 * hooks called by the VFS. 1793 * 1794 * The hook function is expected to populate the xattrs array, by calling 1795 * lsm_get_xattr_slot() to retrieve the slots reserved by the security module 1796 * with the lbs_xattr_count field of the lsm_blob_sizes structure. For each 1797 * slot, the hook function should set ->name to the attribute name suffix 1798 * (e.g. selinux), to allocate ->value (will be freed by the caller) and set it 1799 * to the attribute value, to set ->value_len to the length of the value. If 1800 * the security module does not use security attributes or does not wish to put 1801 * a security attribute on this particular inode, then it should return 1802 * -EOPNOTSUPP to skip this processing. 1803 * 1804 * Return: Returns 0 if the LSM successfully initialized all of the inode 1805 * security attributes that are required, negative values otherwise. 1806 */ 1807 int security_inode_init_security(struct inode *inode, struct inode *dir, 1808 const struct qstr *qstr, 1809 const initxattrs initxattrs, void *fs_data) 1810 { 1811 struct lsm_static_call *scall; 1812 struct xattr *new_xattrs = NULL; 1813 int ret = -EOPNOTSUPP, xattr_count = 0; 1814 1815 if (unlikely(IS_PRIVATE(inode))) 1816 return 0; 1817 1818 if (!blob_sizes.lbs_xattr_count) 1819 return 0; 1820 1821 if (initxattrs) { 1822 /* Allocate +1 as terminator. */ 1823 new_xattrs = kcalloc(blob_sizes.lbs_xattr_count + 1, 1824 sizeof(*new_xattrs), GFP_NOFS); 1825 if (!new_xattrs) 1826 return -ENOMEM; 1827 } 1828 1829 lsm_for_each_hook(scall, inode_init_security) { 1830 ret = scall->hl->hook.inode_init_security(inode, dir, qstr, new_xattrs, 1831 &xattr_count); 1832 if (ret && ret != -EOPNOTSUPP) 1833 goto out; 1834 /* 1835 * As documented in lsm_hooks.h, -EOPNOTSUPP in this context 1836 * means that the LSM is not willing to provide an xattr, not 1837 * that it wants to signal an error. Thus, continue to invoke 1838 * the remaining LSMs. 1839 */ 1840 } 1841 1842 /* If initxattrs() is NULL, xattr_count is zero, skip the call. */ 1843 if (!xattr_count) 1844 goto out; 1845 1846 ret = initxattrs(inode, new_xattrs, fs_data); 1847 out: 1848 for (; xattr_count > 0; xattr_count--) 1849 kfree(new_xattrs[xattr_count - 1].value); 1850 kfree(new_xattrs); 1851 return (ret == -EOPNOTSUPP) ? 0 : ret; 1852 } 1853 EXPORT_SYMBOL(security_inode_init_security); 1854 1855 /** 1856 * security_inode_init_security_anon() - Initialize an anonymous inode 1857 * @inode: the inode 1858 * @name: the anonymous inode class 1859 * @context_inode: an optional related inode 1860 * 1861 * Set up the incore security field for the new anonymous inode and return 1862 * whether the inode creation is permitted by the security module or not. 1863 * 1864 * Return: Returns 0 on success, -EACCES if the security module denies the 1865 * creation of this inode, or another -errno upon other errors. 1866 */ 1867 int security_inode_init_security_anon(struct inode *inode, 1868 const struct qstr *name, 1869 const struct inode *context_inode) 1870 { 1871 return call_int_hook(inode_init_security_anon, inode, name, 1872 context_inode); 1873 } 1874 1875 #ifdef CONFIG_SECURITY_PATH 1876 /** 1877 * security_path_mknod() - Check if creating a special file is allowed 1878 * @dir: parent directory 1879 * @dentry: new file 1880 * @mode: new file mode 1881 * @dev: device number 1882 * 1883 * Check permissions when creating a file. Note that this hook is called even 1884 * if mknod operation is being done for a regular file. 1885 * 1886 * Return: Returns 0 if permission is granted. 1887 */ 1888 int security_path_mknod(const struct path *dir, struct dentry *dentry, 1889 umode_t mode, unsigned int dev) 1890 { 1891 if (unlikely(IS_PRIVATE(d_backing_inode(dir->dentry)))) 1892 return 0; 1893 return call_int_hook(path_mknod, dir, dentry, mode, dev); 1894 } 1895 EXPORT_SYMBOL(security_path_mknod); 1896 1897 /** 1898 * security_path_post_mknod() - Update inode security after reg file creation 1899 * @idmap: idmap of the mount 1900 * @dentry: new file 1901 * 1902 * Update inode security field after a regular file has been created. 1903 */ 1904 void security_path_post_mknod(struct mnt_idmap *idmap, struct dentry *dentry) 1905 { 1906 if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) 1907 return; 1908 call_void_hook(path_post_mknod, idmap, dentry); 1909 } 1910 1911 /** 1912 * security_path_mkdir() - Check if creating a new directory is allowed 1913 * @dir: parent directory 1914 * @dentry: new directory 1915 * @mode: new directory mode 1916 * 1917 * Check permissions to create a new directory in the existing directory. 1918 * 1919 * Return: Returns 0 if permission is granted. 1920 */ 1921 int security_path_mkdir(const struct path *dir, struct dentry *dentry, 1922 umode_t mode) 1923 { 1924 if (unlikely(IS_PRIVATE(d_backing_inode(dir->dentry)))) 1925 return 0; 1926 return call_int_hook(path_mkdir, dir, dentry, mode); 1927 } 1928 EXPORT_SYMBOL(security_path_mkdir); 1929 1930 /** 1931 * security_path_rmdir() - Check if removing a directory is allowed 1932 * @dir: parent directory 1933 * @dentry: directory to remove 1934 * 1935 * Check the permission to remove a directory. 1936 * 1937 * Return: Returns 0 if permission is granted. 1938 */ 1939 int security_path_rmdir(const struct path *dir, struct dentry *dentry) 1940 { 1941 if (unlikely(IS_PRIVATE(d_backing_inode(dir->dentry)))) 1942 return 0; 1943 return call_int_hook(path_rmdir, dir, dentry); 1944 } 1945 1946 /** 1947 * security_path_unlink() - Check if removing a hard link is allowed 1948 * @dir: parent directory 1949 * @dentry: file 1950 * 1951 * Check the permission to remove a hard link to a file. 1952 * 1953 * Return: Returns 0 if permission is granted. 1954 */ 1955 int security_path_unlink(const struct path *dir, struct dentry *dentry) 1956 { 1957 if (unlikely(IS_PRIVATE(d_backing_inode(dir->dentry)))) 1958 return 0; 1959 return call_int_hook(path_unlink, dir, dentry); 1960 } 1961 EXPORT_SYMBOL(security_path_unlink); 1962 1963 /** 1964 * security_path_symlink() - Check if creating a symbolic link is allowed 1965 * @dir: parent directory 1966 * @dentry: symbolic link 1967 * @old_name: file pathname 1968 * 1969 * Check the permission to create a symbolic link to a file. 1970 * 1971 * Return: Returns 0 if permission is granted. 1972 */ 1973 int security_path_symlink(const struct path *dir, struct dentry *dentry, 1974 const char *old_name) 1975 { 1976 if (unlikely(IS_PRIVATE(d_backing_inode(dir->dentry)))) 1977 return 0; 1978 return call_int_hook(path_symlink, dir, dentry, old_name); 1979 } 1980 1981 /** 1982 * security_path_link - Check if creating a hard link is allowed 1983 * @old_dentry: existing file 1984 * @new_dir: new parent directory 1985 * @new_dentry: new link 1986 * 1987 * Check permission before creating a new hard link to a file. 1988 * 1989 * Return: Returns 0 if permission is granted. 1990 */ 1991 int security_path_link(struct dentry *old_dentry, const struct path *new_dir, 1992 struct dentry *new_dentry) 1993 { 1994 if (unlikely(IS_PRIVATE(d_backing_inode(old_dentry)))) 1995 return 0; 1996 return call_int_hook(path_link, old_dentry, new_dir, new_dentry); 1997 } 1998 1999 /** 2000 * security_path_rename() - Check if renaming a file is allowed 2001 * @old_dir: parent directory of the old file 2002 * @old_dentry: the old file 2003 * @new_dir: parent directory of the new file 2004 * @new_dentry: the new file 2005 * @flags: flags 2006 * 2007 * Check for permission to rename a file or directory. 2008 * 2009 * Return: Returns 0 if permission is granted. 2010 */ 2011 int security_path_rename(const struct path *old_dir, struct dentry *old_dentry, 2012 const struct path *new_dir, struct dentry *new_dentry, 2013 unsigned int flags) 2014 { 2015 if (unlikely(IS_PRIVATE(d_backing_inode(old_dentry)) || 2016 (d_is_positive(new_dentry) && 2017 IS_PRIVATE(d_backing_inode(new_dentry))))) 2018 return 0; 2019 2020 return call_int_hook(path_rename, old_dir, old_dentry, new_dir, 2021 new_dentry, flags); 2022 } 2023 EXPORT_SYMBOL(security_path_rename); 2024 2025 /** 2026 * security_path_truncate() - Check if truncating a file is allowed 2027 * @path: file 2028 * 2029 * Check permission before truncating the file indicated by path. Note that 2030 * truncation permissions may also be checked based on already opened files, 2031 * using the security_file_truncate() hook. 2032 * 2033 * Return: Returns 0 if permission is granted. 2034 */ 2035 int security_path_truncate(const struct path *path) 2036 { 2037 if (unlikely(IS_PRIVATE(d_backing_inode(path->dentry)))) 2038 return 0; 2039 return call_int_hook(path_truncate, path); 2040 } 2041 2042 /** 2043 * security_path_chmod() - Check if changing the file's mode is allowed 2044 * @path: file 2045 * @mode: new mode 2046 * 2047 * Check for permission to change a mode of the file @path. The new mode is 2048 * specified in @mode which is a bitmask of constants from 2049 * <include/uapi/linux/stat.h>. 2050 * 2051 * Return: Returns 0 if permission is granted. 2052 */ 2053 int security_path_chmod(const struct path *path, umode_t mode) 2054 { 2055 if (unlikely(IS_PRIVATE(d_backing_inode(path->dentry)))) 2056 return 0; 2057 return call_int_hook(path_chmod, path, mode); 2058 } 2059 2060 /** 2061 * security_path_chown() - Check if changing the file's owner/group is allowed 2062 * @path: file 2063 * @uid: file owner 2064 * @gid: file group 2065 * 2066 * Check for permission to change owner/group of a file or directory. 2067 * 2068 * Return: Returns 0 if permission is granted. 2069 */ 2070 int security_path_chown(const struct path *path, kuid_t uid, kgid_t gid) 2071 { 2072 if (unlikely(IS_PRIVATE(d_backing_inode(path->dentry)))) 2073 return 0; 2074 return call_int_hook(path_chown, path, uid, gid); 2075 } 2076 2077 /** 2078 * security_path_chroot() - Check if changing the root directory is allowed 2079 * @path: directory 2080 * 2081 * Check for permission to change root directory. 2082 * 2083 * Return: Returns 0 if permission is granted. 2084 */ 2085 int security_path_chroot(const struct path *path) 2086 { 2087 return call_int_hook(path_chroot, path); 2088 } 2089 #endif /* CONFIG_SECURITY_PATH */ 2090 2091 /** 2092 * security_inode_create() - Check if creating a file is allowed 2093 * @dir: the parent directory 2094 * @dentry: the file being created 2095 * @mode: requested file mode 2096 * 2097 * Check permission to create a regular file. 2098 * 2099 * Return: Returns 0 if permission is granted. 2100 */ 2101 int security_inode_create(struct inode *dir, struct dentry *dentry, 2102 umode_t mode) 2103 { 2104 if (unlikely(IS_PRIVATE(dir))) 2105 return 0; 2106 return call_int_hook(inode_create, dir, dentry, mode); 2107 } 2108 EXPORT_SYMBOL_GPL(security_inode_create); 2109 2110 /** 2111 * security_inode_post_create_tmpfile() - Update inode security of new tmpfile 2112 * @idmap: idmap of the mount 2113 * @inode: inode of the new tmpfile 2114 * 2115 * Update inode security data after a tmpfile has been created. 2116 */ 2117 void security_inode_post_create_tmpfile(struct mnt_idmap *idmap, 2118 struct inode *inode) 2119 { 2120 if (unlikely(IS_PRIVATE(inode))) 2121 return; 2122 call_void_hook(inode_post_create_tmpfile, idmap, inode); 2123 } 2124 2125 /** 2126 * security_inode_link() - Check if creating a hard link is allowed 2127 * @old_dentry: existing file 2128 * @dir: new parent directory 2129 * @new_dentry: new link 2130 * 2131 * Check permission before creating a new hard link to a file. 2132 * 2133 * Return: Returns 0 if permission is granted. 2134 */ 2135 int security_inode_link(struct dentry *old_dentry, struct inode *dir, 2136 struct dentry *new_dentry) 2137 { 2138 if (unlikely(IS_PRIVATE(d_backing_inode(old_dentry)))) 2139 return 0; 2140 return call_int_hook(inode_link, old_dentry, dir, new_dentry); 2141 } 2142 2143 /** 2144 * security_inode_unlink() - Check if removing a hard link is allowed 2145 * @dir: parent directory 2146 * @dentry: file 2147 * 2148 * Check the permission to remove a hard link to a file. 2149 * 2150 * Return: Returns 0 if permission is granted. 2151 */ 2152 int security_inode_unlink(struct inode *dir, struct dentry *dentry) 2153 { 2154 if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) 2155 return 0; 2156 return call_int_hook(inode_unlink, dir, dentry); 2157 } 2158 2159 /** 2160 * security_inode_symlink() - Check if creating a symbolic link is allowed 2161 * @dir: parent directory 2162 * @dentry: symbolic link 2163 * @old_name: existing filename 2164 * 2165 * Check the permission to create a symbolic link to a file. 2166 * 2167 * Return: Returns 0 if permission is granted. 2168 */ 2169 int security_inode_symlink(struct inode *dir, struct dentry *dentry, 2170 const char *old_name) 2171 { 2172 if (unlikely(IS_PRIVATE(dir))) 2173 return 0; 2174 return call_int_hook(inode_symlink, dir, dentry, old_name); 2175 } 2176 2177 /** 2178 * security_inode_mkdir() - Check if creation a new director is allowed 2179 * @dir: parent directory 2180 * @dentry: new directory 2181 * @mode: new directory mode 2182 * 2183 * Check permissions to create a new directory in the existing directory 2184 * associated with inode structure @dir. 2185 * 2186 * Return: Returns 0 if permission is granted. 2187 */ 2188 int security_inode_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode) 2189 { 2190 if (unlikely(IS_PRIVATE(dir))) 2191 return 0; 2192 return call_int_hook(inode_mkdir, dir, dentry, mode); 2193 } 2194 EXPORT_SYMBOL_GPL(security_inode_mkdir); 2195 2196 /** 2197 * security_inode_rmdir() - Check if removing a directory is allowed 2198 * @dir: parent directory 2199 * @dentry: directory to be removed 2200 * 2201 * Check the permission to remove a directory. 2202 * 2203 * Return: Returns 0 if permission is granted. 2204 */ 2205 int security_inode_rmdir(struct inode *dir, struct dentry *dentry) 2206 { 2207 if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) 2208 return 0; 2209 return call_int_hook(inode_rmdir, dir, dentry); 2210 } 2211 2212 /** 2213 * security_inode_mknod() - Check if creating a special file is allowed 2214 * @dir: parent directory 2215 * @dentry: new file 2216 * @mode: new file mode 2217 * @dev: device number 2218 * 2219 * Check permissions when creating a special file (or a socket or a fifo file 2220 * created via the mknod system call). Note that if mknod operation is being 2221 * done for a regular file, then the create hook will be called and not this 2222 * hook. 2223 * 2224 * Return: Returns 0 if permission is granted. 2225 */ 2226 int security_inode_mknod(struct inode *dir, struct dentry *dentry, 2227 umode_t mode, dev_t dev) 2228 { 2229 if (unlikely(IS_PRIVATE(dir))) 2230 return 0; 2231 return call_int_hook(inode_mknod, dir, dentry, mode, dev); 2232 } 2233 2234 /** 2235 * security_inode_rename() - Check if renaming a file is allowed 2236 * @old_dir: parent directory of the old file 2237 * @old_dentry: the old file 2238 * @new_dir: parent directory of the new file 2239 * @new_dentry: the new file 2240 * @flags: flags 2241 * 2242 * Check for permission to rename a file or directory. 2243 * 2244 * Return: Returns 0 if permission is granted. 2245 */ 2246 int security_inode_rename(struct inode *old_dir, struct dentry *old_dentry, 2247 struct inode *new_dir, struct dentry *new_dentry, 2248 unsigned int flags) 2249 { 2250 if (unlikely(IS_PRIVATE(d_backing_inode(old_dentry)) || 2251 (d_is_positive(new_dentry) && 2252 IS_PRIVATE(d_backing_inode(new_dentry))))) 2253 return 0; 2254 2255 if (flags & RENAME_EXCHANGE) { 2256 int err = call_int_hook(inode_rename, new_dir, new_dentry, 2257 old_dir, old_dentry); 2258 if (err) 2259 return err; 2260 } 2261 2262 return call_int_hook(inode_rename, old_dir, old_dentry, 2263 new_dir, new_dentry); 2264 } 2265 2266 /** 2267 * security_inode_readlink() - Check if reading a symbolic link is allowed 2268 * @dentry: link 2269 * 2270 * Check the permission to read the symbolic link. 2271 * 2272 * Return: Returns 0 if permission is granted. 2273 */ 2274 int security_inode_readlink(struct dentry *dentry) 2275 { 2276 if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) 2277 return 0; 2278 return call_int_hook(inode_readlink, dentry); 2279 } 2280 2281 /** 2282 * security_inode_follow_link() - Check if following a symbolic link is allowed 2283 * @dentry: link dentry 2284 * @inode: link inode 2285 * @rcu: true if in RCU-walk mode 2286 * 2287 * Check permission to follow a symbolic link when looking up a pathname. If 2288 * @rcu is true, @inode is not stable. 2289 * 2290 * Return: Returns 0 if permission is granted. 2291 */ 2292 int security_inode_follow_link(struct dentry *dentry, struct inode *inode, 2293 bool rcu) 2294 { 2295 if (unlikely(IS_PRIVATE(inode))) 2296 return 0; 2297 return call_int_hook(inode_follow_link, dentry, inode, rcu); 2298 } 2299 2300 /** 2301 * security_inode_permission() - Check if accessing an inode is allowed 2302 * @inode: inode 2303 * @mask: access mask 2304 * 2305 * Check permission before accessing an inode. This hook is called by the 2306 * existing Linux permission function, so a security module can use it to 2307 * provide additional checking for existing Linux permission checks. Notice 2308 * that this hook is called when a file is opened (as well as many other 2309 * operations), whereas the file_security_ops permission hook is called when 2310 * the actual read/write operations are performed. 2311 * 2312 * Return: Returns 0 if permission is granted. 2313 */ 2314 int security_inode_permission(struct inode *inode, int mask) 2315 { 2316 if (unlikely(IS_PRIVATE(inode))) 2317 return 0; 2318 return call_int_hook(inode_permission, inode, mask); 2319 } 2320 2321 /** 2322 * security_inode_setattr() - Check if setting file attributes is allowed 2323 * @idmap: idmap of the mount 2324 * @dentry: file 2325 * @attr: new attributes 2326 * 2327 * Check permission before setting file attributes. Note that the kernel call 2328 * to notify_change is performed from several locations, whenever file 2329 * attributes change (such as when a file is truncated, chown/chmod operations, 2330 * transferring disk quotas, etc). 2331 * 2332 * Return: Returns 0 if permission is granted. 2333 */ 2334 int security_inode_setattr(struct mnt_idmap *idmap, 2335 struct dentry *dentry, struct iattr *attr) 2336 { 2337 if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) 2338 return 0; 2339 return call_int_hook(inode_setattr, idmap, dentry, attr); 2340 } 2341 EXPORT_SYMBOL_GPL(security_inode_setattr); 2342 2343 /** 2344 * security_inode_post_setattr() - Update the inode after a setattr operation 2345 * @idmap: idmap of the mount 2346 * @dentry: file 2347 * @ia_valid: file attributes set 2348 * 2349 * Update inode security field after successful setting file attributes. 2350 */ 2351 void security_inode_post_setattr(struct mnt_idmap *idmap, struct dentry *dentry, 2352 int ia_valid) 2353 { 2354 if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) 2355 return; 2356 call_void_hook(inode_post_setattr, idmap, dentry, ia_valid); 2357 } 2358 2359 /** 2360 * security_inode_getattr() - Check if getting file attributes is allowed 2361 * @path: file 2362 * 2363 * Check permission before obtaining file attributes. 2364 * 2365 * Return: Returns 0 if permission is granted. 2366 */ 2367 int security_inode_getattr(const struct path *path) 2368 { 2369 if (unlikely(IS_PRIVATE(d_backing_inode(path->dentry)))) 2370 return 0; 2371 return call_int_hook(inode_getattr, path); 2372 } 2373 2374 /** 2375 * security_inode_setxattr() - Check if setting file xattrs is allowed 2376 * @idmap: idmap of the mount 2377 * @dentry: file 2378 * @name: xattr name 2379 * @value: xattr value 2380 * @size: size of xattr value 2381 * @flags: flags 2382 * 2383 * This hook performs the desired permission checks before setting the extended 2384 * attributes (xattrs) on @dentry. It is important to note that we have some 2385 * additional logic before the main LSM implementation calls to detect if we 2386 * need to perform an additional capability check at the LSM layer. 2387 * 2388 * Normally we enforce a capability check prior to executing the various LSM 2389 * hook implementations, but if a LSM wants to avoid this capability check, 2390 * it can register a 'inode_xattr_skipcap' hook and return a value of 1 for 2391 * xattrs that it wants to avoid the capability check, leaving the LSM fully 2392 * responsible for enforcing the access control for the specific xattr. If all 2393 * of the enabled LSMs refrain from registering a 'inode_xattr_skipcap' hook, 2394 * or return a 0 (the default return value), the capability check is still 2395 * performed. If no 'inode_xattr_skipcap' hooks are registered the capability 2396 * check is performed. 2397 * 2398 * Return: Returns 0 if permission is granted. 2399 */ 2400 int security_inode_setxattr(struct mnt_idmap *idmap, 2401 struct dentry *dentry, const char *name, 2402 const void *value, size_t size, int flags) 2403 { 2404 int rc; 2405 2406 if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) 2407 return 0; 2408 2409 /* enforce the capability checks at the lsm layer, if needed */ 2410 if (!call_int_hook(inode_xattr_skipcap, name)) { 2411 rc = cap_inode_setxattr(dentry, name, value, size, flags); 2412 if (rc) 2413 return rc; 2414 } 2415 2416 return call_int_hook(inode_setxattr, idmap, dentry, name, value, size, 2417 flags); 2418 } 2419 2420 /** 2421 * security_inode_set_acl() - Check if setting posix acls is allowed 2422 * @idmap: idmap of the mount 2423 * @dentry: file 2424 * @acl_name: acl name 2425 * @kacl: acl struct 2426 * 2427 * Check permission before setting posix acls, the posix acls in @kacl are 2428 * identified by @acl_name. 2429 * 2430 * Return: Returns 0 if permission is granted. 2431 */ 2432 int security_inode_set_acl(struct mnt_idmap *idmap, 2433 struct dentry *dentry, const char *acl_name, 2434 struct posix_acl *kacl) 2435 { 2436 if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) 2437 return 0; 2438 return call_int_hook(inode_set_acl, idmap, dentry, acl_name, kacl); 2439 } 2440 2441 /** 2442 * security_inode_post_set_acl() - Update inode security from posix acls set 2443 * @dentry: file 2444 * @acl_name: acl name 2445 * @kacl: acl struct 2446 * 2447 * Update inode security data after successfully setting posix acls on @dentry. 2448 * The posix acls in @kacl are identified by @acl_name. 2449 */ 2450 void security_inode_post_set_acl(struct dentry *dentry, const char *acl_name, 2451 struct posix_acl *kacl) 2452 { 2453 if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) 2454 return; 2455 call_void_hook(inode_post_set_acl, dentry, acl_name, kacl); 2456 } 2457 2458 /** 2459 * security_inode_get_acl() - Check if reading posix acls is allowed 2460 * @idmap: idmap of the mount 2461 * @dentry: file 2462 * @acl_name: acl name 2463 * 2464 * Check permission before getting osix acls, the posix acls are identified by 2465 * @acl_name. 2466 * 2467 * Return: Returns 0 if permission is granted. 2468 */ 2469 int security_inode_get_acl(struct mnt_idmap *idmap, 2470 struct dentry *dentry, const char *acl_name) 2471 { 2472 if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) 2473 return 0; 2474 return call_int_hook(inode_get_acl, idmap, dentry, acl_name); 2475 } 2476 2477 /** 2478 * security_inode_remove_acl() - Check if removing a posix acl is allowed 2479 * @idmap: idmap of the mount 2480 * @dentry: file 2481 * @acl_name: acl name 2482 * 2483 * Check permission before removing posix acls, the posix acls are identified 2484 * by @acl_name. 2485 * 2486 * Return: Returns 0 if permission is granted. 2487 */ 2488 int security_inode_remove_acl(struct mnt_idmap *idmap, 2489 struct dentry *dentry, const char *acl_name) 2490 { 2491 if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) 2492 return 0; 2493 return call_int_hook(inode_remove_acl, idmap, dentry, acl_name); 2494 } 2495 2496 /** 2497 * security_inode_post_remove_acl() - Update inode security after rm posix acls 2498 * @idmap: idmap of the mount 2499 * @dentry: file 2500 * @acl_name: acl name 2501 * 2502 * Update inode security data after successfully removing posix acls on 2503 * @dentry in @idmap. The posix acls are identified by @acl_name. 2504 */ 2505 void security_inode_post_remove_acl(struct mnt_idmap *idmap, 2506 struct dentry *dentry, const char *acl_name) 2507 { 2508 if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) 2509 return; 2510 call_void_hook(inode_post_remove_acl, idmap, dentry, acl_name); 2511 } 2512 2513 /** 2514 * security_inode_post_setxattr() - Update the inode after a setxattr operation 2515 * @dentry: file 2516 * @name: xattr name 2517 * @value: xattr value 2518 * @size: xattr value size 2519 * @flags: flags 2520 * 2521 * Update inode security field after successful setxattr operation. 2522 */ 2523 void security_inode_post_setxattr(struct dentry *dentry, const char *name, 2524 const void *value, size_t size, int flags) 2525 { 2526 if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) 2527 return; 2528 call_void_hook(inode_post_setxattr, dentry, name, value, size, flags); 2529 } 2530 2531 /** 2532 * security_inode_getxattr() - Check if xattr access is allowed 2533 * @dentry: file 2534 * @name: xattr name 2535 * 2536 * Check permission before obtaining the extended attributes identified by 2537 * @name for @dentry. 2538 * 2539 * Return: Returns 0 if permission is granted. 2540 */ 2541 int security_inode_getxattr(struct dentry *dentry, const char *name) 2542 { 2543 if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) 2544 return 0; 2545 return call_int_hook(inode_getxattr, dentry, name); 2546 } 2547 2548 /** 2549 * security_inode_listxattr() - Check if listing xattrs is allowed 2550 * @dentry: file 2551 * 2552 * Check permission before obtaining the list of extended attribute names for 2553 * @dentry. 2554 * 2555 * Return: Returns 0 if permission is granted. 2556 */ 2557 int security_inode_listxattr(struct dentry *dentry) 2558 { 2559 if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) 2560 return 0; 2561 return call_int_hook(inode_listxattr, dentry); 2562 } 2563 2564 /** 2565 * security_inode_removexattr() - Check if removing an xattr is allowed 2566 * @idmap: idmap of the mount 2567 * @dentry: file 2568 * @name: xattr name 2569 * 2570 * This hook performs the desired permission checks before setting the extended 2571 * attributes (xattrs) on @dentry. It is important to note that we have some 2572 * additional logic before the main LSM implementation calls to detect if we 2573 * need to perform an additional capability check at the LSM layer. 2574 * 2575 * Normally we enforce a capability check prior to executing the various LSM 2576 * hook implementations, but if a LSM wants to avoid this capability check, 2577 * it can register a 'inode_xattr_skipcap' hook and return a value of 1 for 2578 * xattrs that it wants to avoid the capability check, leaving the LSM fully 2579 * responsible for enforcing the access control for the specific xattr. If all 2580 * of the enabled LSMs refrain from registering a 'inode_xattr_skipcap' hook, 2581 * or return a 0 (the default return value), the capability check is still 2582 * performed. If no 'inode_xattr_skipcap' hooks are registered the capability 2583 * check is performed. 2584 * 2585 * Return: Returns 0 if permission is granted. 2586 */ 2587 int security_inode_removexattr(struct mnt_idmap *idmap, 2588 struct dentry *dentry, const char *name) 2589 { 2590 int rc; 2591 2592 if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) 2593 return 0; 2594 2595 /* enforce the capability checks at the lsm layer, if needed */ 2596 if (!call_int_hook(inode_xattr_skipcap, name)) { 2597 rc = cap_inode_removexattr(idmap, dentry, name); 2598 if (rc) 2599 return rc; 2600 } 2601 2602 return call_int_hook(inode_removexattr, idmap, dentry, name); 2603 } 2604 2605 /** 2606 * security_inode_post_removexattr() - Update the inode after a removexattr op 2607 * @dentry: file 2608 * @name: xattr name 2609 * 2610 * Update the inode after a successful removexattr operation. 2611 */ 2612 void security_inode_post_removexattr(struct dentry *dentry, const char *name) 2613 { 2614 if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) 2615 return; 2616 call_void_hook(inode_post_removexattr, dentry, name); 2617 } 2618 2619 /** 2620 * security_inode_need_killpriv() - Check if security_inode_killpriv() required 2621 * @dentry: associated dentry 2622 * 2623 * Called when an inode has been changed to determine if 2624 * security_inode_killpriv() should be called. 2625 * 2626 * Return: Return <0 on error to abort the inode change operation, return 0 if 2627 * security_inode_killpriv() does not need to be called, return >0 if 2628 * security_inode_killpriv() does need to be called. 2629 */ 2630 int security_inode_need_killpriv(struct dentry *dentry) 2631 { 2632 return call_int_hook(inode_need_killpriv, dentry); 2633 } 2634 2635 /** 2636 * security_inode_killpriv() - The setuid bit is removed, update LSM state 2637 * @idmap: idmap of the mount 2638 * @dentry: associated dentry 2639 * 2640 * The @dentry's setuid bit is being removed. Remove similar security labels. 2641 * Called with the dentry->d_inode->i_mutex held. 2642 * 2643 * Return: Return 0 on success. If error is returned, then the operation 2644 * causing setuid bit removal is failed. 2645 */ 2646 int security_inode_killpriv(struct mnt_idmap *idmap, 2647 struct dentry *dentry) 2648 { 2649 return call_int_hook(inode_killpriv, idmap, dentry); 2650 } 2651 2652 /** 2653 * security_inode_getsecurity() - Get the xattr security label of an inode 2654 * @idmap: idmap of the mount 2655 * @inode: inode 2656 * @name: xattr name 2657 * @buffer: security label buffer 2658 * @alloc: allocation flag 2659 * 2660 * Retrieve a copy of the extended attribute representation of the security 2661 * label associated with @name for @inode via @buffer. Note that @name is the 2662 * remainder of the attribute name after the security prefix has been removed. 2663 * @alloc is used to specify if the call should return a value via the buffer 2664 * or just the value length. 2665 * 2666 * Return: Returns size of buffer on success. 2667 */ 2668 int security_inode_getsecurity(struct mnt_idmap *idmap, 2669 struct inode *inode, const char *name, 2670 void **buffer, bool alloc) 2671 { 2672 if (unlikely(IS_PRIVATE(inode))) 2673 return LSM_RET_DEFAULT(inode_getsecurity); 2674 2675 return call_int_hook(inode_getsecurity, idmap, inode, name, buffer, 2676 alloc); 2677 } 2678 2679 /** 2680 * security_inode_setsecurity() - Set the xattr security label of an inode 2681 * @inode: inode 2682 * @name: xattr name 2683 * @value: security label 2684 * @size: length of security label 2685 * @flags: flags 2686 * 2687 * Set the security label associated with @name for @inode from the extended 2688 * attribute value @value. @size indicates the size of the @value in bytes. 2689 * @flags may be XATTR_CREATE, XATTR_REPLACE, or 0. Note that @name is the 2690 * remainder of the attribute name after the security. prefix has been removed. 2691 * 2692 * Return: Returns 0 on success. 2693 */ 2694 int security_inode_setsecurity(struct inode *inode, const char *name, 2695 const void *value, size_t size, int flags) 2696 { 2697 if (unlikely(IS_PRIVATE(inode))) 2698 return LSM_RET_DEFAULT(inode_setsecurity); 2699 2700 return call_int_hook(inode_setsecurity, inode, name, value, size, 2701 flags); 2702 } 2703 2704 /** 2705 * security_inode_listsecurity() - List the xattr security label names 2706 * @inode: inode 2707 * @buffer: buffer 2708 * @buffer_size: size of buffer 2709 * 2710 * Copy the extended attribute names for the security labels associated with 2711 * @inode into @buffer. The maximum size of @buffer is specified by 2712 * @buffer_size. @buffer may be NULL to request the size of the buffer 2713 * required. 2714 * 2715 * Return: Returns number of bytes used/required on success. 2716 */ 2717 int security_inode_listsecurity(struct inode *inode, 2718 char *buffer, size_t buffer_size) 2719 { 2720 if (unlikely(IS_PRIVATE(inode))) 2721 return 0; 2722 return call_int_hook(inode_listsecurity, inode, buffer, buffer_size); 2723 } 2724 EXPORT_SYMBOL(security_inode_listsecurity); 2725 2726 /** 2727 * security_inode_getsecid() - Get an inode's secid 2728 * @inode: inode 2729 * @secid: secid to return 2730 * 2731 * Get the secid associated with the node. In case of failure, @secid will be 2732 * set to zero. 2733 */ 2734 void security_inode_getsecid(struct inode *inode, u32 *secid) 2735 { 2736 call_void_hook(inode_getsecid, inode, secid); 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 int ret; 3106 3107 ret = call_int_hook(file_open, file); 3108 if (ret) 3109 return ret; 3110 3111 return fsnotify_open_perm(file); 3112 } 3113 3114 /** 3115 * security_file_post_open() - Evaluate a file after it has been opened 3116 * @file: the file 3117 * @mask: access mask 3118 * 3119 * Evaluate an opened file and the access mask requested with open(). The hook 3120 * is useful for LSMs that require the file content to be available in order to 3121 * make decisions. 3122 * 3123 * Return: Returns 0 if permission is granted. 3124 */ 3125 int security_file_post_open(struct file *file, int mask) 3126 { 3127 return call_int_hook(file_post_open, file, mask); 3128 } 3129 EXPORT_SYMBOL_GPL(security_file_post_open); 3130 3131 /** 3132 * security_file_truncate() - Check if truncating a file is allowed 3133 * @file: file 3134 * 3135 * Check permission before truncating a file, i.e. using ftruncate. Note that 3136 * truncation permission may also be checked based on the path, using the 3137 * @path_truncate hook. 3138 * 3139 * Return: Returns 0 if permission is granted. 3140 */ 3141 int security_file_truncate(struct file *file) 3142 { 3143 return call_int_hook(file_truncate, file); 3144 } 3145 3146 /** 3147 * security_task_alloc() - Allocate a task's LSM blob 3148 * @task: the task 3149 * @clone_flags: flags indicating what is being shared 3150 * 3151 * Handle allocation of task-related resources. 3152 * 3153 * Return: Returns a zero on success, negative values on failure. 3154 */ 3155 int security_task_alloc(struct task_struct *task, unsigned long clone_flags) 3156 { 3157 int rc = lsm_task_alloc(task); 3158 3159 if (rc) 3160 return rc; 3161 rc = call_int_hook(task_alloc, task, clone_flags); 3162 if (unlikely(rc)) 3163 security_task_free(task); 3164 return rc; 3165 } 3166 3167 /** 3168 * security_task_free() - Free a task's LSM blob and related resources 3169 * @task: task 3170 * 3171 * Handle release of task-related resources. Note that this can be called from 3172 * interrupt context. 3173 */ 3174 void security_task_free(struct task_struct *task) 3175 { 3176 call_void_hook(task_free, task); 3177 3178 kfree(task->security); 3179 task->security = NULL; 3180 } 3181 3182 /** 3183 * security_cred_alloc_blank() - Allocate the min memory to allow cred_transfer 3184 * @cred: credentials 3185 * @gfp: gfp flags 3186 * 3187 * Only allocate sufficient memory and attach to @cred such that 3188 * cred_transfer() will not get ENOMEM. 3189 * 3190 * Return: Returns 0 on success, negative values on failure. 3191 */ 3192 int security_cred_alloc_blank(struct cred *cred, gfp_t gfp) 3193 { 3194 int rc = lsm_cred_alloc(cred, gfp); 3195 3196 if (rc) 3197 return rc; 3198 3199 rc = call_int_hook(cred_alloc_blank, cred, gfp); 3200 if (unlikely(rc)) 3201 security_cred_free(cred); 3202 return rc; 3203 } 3204 3205 /** 3206 * security_cred_free() - Free the cred's LSM blob and associated resources 3207 * @cred: credentials 3208 * 3209 * Deallocate and clear the cred->security field in a set of credentials. 3210 */ 3211 void security_cred_free(struct cred *cred) 3212 { 3213 /* 3214 * There is a failure case in prepare_creds() that 3215 * may result in a call here with ->security being NULL. 3216 */ 3217 if (unlikely(cred->security == NULL)) 3218 return; 3219 3220 call_void_hook(cred_free, cred); 3221 3222 kfree(cred->security); 3223 cred->security = NULL; 3224 } 3225 3226 /** 3227 * security_prepare_creds() - Prepare a new set of credentials 3228 * @new: new credentials 3229 * @old: original credentials 3230 * @gfp: gfp flags 3231 * 3232 * Prepare a new set of credentials by copying the data from the old set. 3233 * 3234 * Return: Returns 0 on success, negative values on failure. 3235 */ 3236 int security_prepare_creds(struct cred *new, const struct cred *old, gfp_t gfp) 3237 { 3238 int rc = lsm_cred_alloc(new, gfp); 3239 3240 if (rc) 3241 return rc; 3242 3243 rc = call_int_hook(cred_prepare, new, old, gfp); 3244 if (unlikely(rc)) 3245 security_cred_free(new); 3246 return rc; 3247 } 3248 3249 /** 3250 * security_transfer_creds() - Transfer creds 3251 * @new: target credentials 3252 * @old: original credentials 3253 * 3254 * Transfer data from original creds to new creds. 3255 */ 3256 void security_transfer_creds(struct cred *new, const struct cred *old) 3257 { 3258 call_void_hook(cred_transfer, new, old); 3259 } 3260 3261 /** 3262 * security_cred_getsecid() - Get the secid from a set of credentials 3263 * @c: credentials 3264 * @secid: secid value 3265 * 3266 * Retrieve the security identifier of the cred structure @c. In case of 3267 * failure, @secid will be set to zero. 3268 */ 3269 void security_cred_getsecid(const struct cred *c, u32 *secid) 3270 { 3271 *secid = 0; 3272 call_void_hook(cred_getsecid, c, secid); 3273 } 3274 EXPORT_SYMBOL(security_cred_getsecid); 3275 3276 /** 3277 * security_kernel_act_as() - Set the kernel credentials to act as secid 3278 * @new: credentials 3279 * @secid: secid 3280 * 3281 * Set the credentials for a kernel service to act as (subjective context). 3282 * The current task must be the one that nominated @secid. 3283 * 3284 * Return: Returns 0 if successful. 3285 */ 3286 int security_kernel_act_as(struct cred *new, u32 secid) 3287 { 3288 return call_int_hook(kernel_act_as, new, secid); 3289 } 3290 3291 /** 3292 * security_kernel_create_files_as() - Set file creation context using an inode 3293 * @new: target credentials 3294 * @inode: reference inode 3295 * 3296 * Set the file creation context in a set of credentials to be the same as the 3297 * objective context of the specified inode. The current task must be the one 3298 * that nominated @inode. 3299 * 3300 * Return: Returns 0 if successful. 3301 */ 3302 int security_kernel_create_files_as(struct cred *new, struct inode *inode) 3303 { 3304 return call_int_hook(kernel_create_files_as, new, inode); 3305 } 3306 3307 /** 3308 * security_kernel_module_request() - Check if loading a module is allowed 3309 * @kmod_name: module name 3310 * 3311 * Ability to trigger the kernel to automatically upcall to userspace for 3312 * userspace to load a kernel module with the given name. 3313 * 3314 * Return: Returns 0 if successful. 3315 */ 3316 int security_kernel_module_request(char *kmod_name) 3317 { 3318 return call_int_hook(kernel_module_request, kmod_name); 3319 } 3320 3321 /** 3322 * security_kernel_read_file() - Read a file specified by userspace 3323 * @file: file 3324 * @id: file identifier 3325 * @contents: trust if security_kernel_post_read_file() will be called 3326 * 3327 * Read a file specified by userspace. 3328 * 3329 * Return: Returns 0 if permission is granted. 3330 */ 3331 int security_kernel_read_file(struct file *file, enum kernel_read_file_id id, 3332 bool contents) 3333 { 3334 return call_int_hook(kernel_read_file, file, id, contents); 3335 } 3336 EXPORT_SYMBOL_GPL(security_kernel_read_file); 3337 3338 /** 3339 * security_kernel_post_read_file() - Read a file specified by userspace 3340 * @file: file 3341 * @buf: file contents 3342 * @size: size of file contents 3343 * @id: file identifier 3344 * 3345 * Read a file specified by userspace. This must be paired with a prior call 3346 * to security_kernel_read_file() call that indicated this hook would also be 3347 * called, see security_kernel_read_file() for more information. 3348 * 3349 * Return: Returns 0 if permission is granted. 3350 */ 3351 int security_kernel_post_read_file(struct file *file, char *buf, loff_t size, 3352 enum kernel_read_file_id id) 3353 { 3354 return call_int_hook(kernel_post_read_file, file, buf, size, id); 3355 } 3356 EXPORT_SYMBOL_GPL(security_kernel_post_read_file); 3357 3358 /** 3359 * security_kernel_load_data() - Load data provided by userspace 3360 * @id: data identifier 3361 * @contents: true if security_kernel_post_load_data() will be called 3362 * 3363 * Load data provided by userspace. 3364 * 3365 * Return: Returns 0 if permission is granted. 3366 */ 3367 int security_kernel_load_data(enum kernel_load_data_id id, bool contents) 3368 { 3369 return call_int_hook(kernel_load_data, id, contents); 3370 } 3371 EXPORT_SYMBOL_GPL(security_kernel_load_data); 3372 3373 /** 3374 * security_kernel_post_load_data() - Load userspace data from a non-file source 3375 * @buf: data 3376 * @size: size of data 3377 * @id: data identifier 3378 * @description: text description of data, specific to the id value 3379 * 3380 * Load data provided by a non-file source (usually userspace buffer). This 3381 * must be paired with a prior security_kernel_load_data() call that indicated 3382 * this hook would also be called, see security_kernel_load_data() for more 3383 * information. 3384 * 3385 * Return: Returns 0 if permission is granted. 3386 */ 3387 int security_kernel_post_load_data(char *buf, loff_t size, 3388 enum kernel_load_data_id id, 3389 char *description) 3390 { 3391 return call_int_hook(kernel_post_load_data, buf, size, id, description); 3392 } 3393 EXPORT_SYMBOL_GPL(security_kernel_post_load_data); 3394 3395 /** 3396 * security_task_fix_setuid() - Update LSM with new user id attributes 3397 * @new: updated credentials 3398 * @old: credentials being replaced 3399 * @flags: LSM_SETID_* flag values 3400 * 3401 * Update the module's state after setting one or more of the user identity 3402 * attributes of the current process. The @flags parameter indicates which of 3403 * the set*uid system calls invoked this hook. If @new is the set of 3404 * credentials that will be installed. Modifications should be made to this 3405 * rather than to @current->cred. 3406 * 3407 * Return: Returns 0 on success. 3408 */ 3409 int security_task_fix_setuid(struct cred *new, const struct cred *old, 3410 int flags) 3411 { 3412 return call_int_hook(task_fix_setuid, new, old, flags); 3413 } 3414 3415 /** 3416 * security_task_fix_setgid() - Update LSM with new group id attributes 3417 * @new: updated credentials 3418 * @old: credentials being replaced 3419 * @flags: LSM_SETID_* flag value 3420 * 3421 * Update the module's state after setting one or more of the group identity 3422 * attributes of the current process. The @flags parameter indicates which of 3423 * the set*gid system calls invoked this hook. @new is the set of credentials 3424 * that will be installed. Modifications should be made to this rather than to 3425 * @current->cred. 3426 * 3427 * Return: Returns 0 on success. 3428 */ 3429 int security_task_fix_setgid(struct cred *new, const struct cred *old, 3430 int flags) 3431 { 3432 return call_int_hook(task_fix_setgid, new, old, flags); 3433 } 3434 3435 /** 3436 * security_task_fix_setgroups() - Update LSM with new supplementary groups 3437 * @new: updated credentials 3438 * @old: credentials being replaced 3439 * 3440 * Update the module's state after setting the supplementary group identity 3441 * attributes of the current process. @new is the set of credentials that will 3442 * be installed. Modifications should be made to this rather than to 3443 * @current->cred. 3444 * 3445 * Return: Returns 0 on success. 3446 */ 3447 int security_task_fix_setgroups(struct cred *new, const struct cred *old) 3448 { 3449 return call_int_hook(task_fix_setgroups, new, old); 3450 } 3451 3452 /** 3453 * security_task_setpgid() - Check if setting the pgid is allowed 3454 * @p: task being modified 3455 * @pgid: new pgid 3456 * 3457 * Check permission before setting the process group identifier of the process 3458 * @p to @pgid. 3459 * 3460 * Return: Returns 0 if permission is granted. 3461 */ 3462 int security_task_setpgid(struct task_struct *p, pid_t pgid) 3463 { 3464 return call_int_hook(task_setpgid, p, pgid); 3465 } 3466 3467 /** 3468 * security_task_getpgid() - Check if getting the pgid is allowed 3469 * @p: task 3470 * 3471 * Check permission before getting the process group identifier of the process 3472 * @p. 3473 * 3474 * Return: Returns 0 if permission is granted. 3475 */ 3476 int security_task_getpgid(struct task_struct *p) 3477 { 3478 return call_int_hook(task_getpgid, p); 3479 } 3480 3481 /** 3482 * security_task_getsid() - Check if getting the session id is allowed 3483 * @p: task 3484 * 3485 * Check permission before getting the session identifier of the process @p. 3486 * 3487 * Return: Returns 0 if permission is granted. 3488 */ 3489 int security_task_getsid(struct task_struct *p) 3490 { 3491 return call_int_hook(task_getsid, p); 3492 } 3493 3494 /** 3495 * security_current_getsecid_subj() - Get the current task's subjective secid 3496 * @secid: secid value 3497 * 3498 * Retrieve the subjective security identifier of the current task and return 3499 * it in @secid. In case of failure, @secid will be set to zero. 3500 */ 3501 void security_current_getsecid_subj(u32 *secid) 3502 { 3503 *secid = 0; 3504 call_void_hook(current_getsecid_subj, secid); 3505 } 3506 EXPORT_SYMBOL(security_current_getsecid_subj); 3507 3508 /** 3509 * security_task_getsecid_obj() - Get a task's objective secid 3510 * @p: target task 3511 * @secid: secid value 3512 * 3513 * Retrieve the objective security identifier of the task_struct in @p and 3514 * return it in @secid. In case of failure, @secid will be set to zero. 3515 */ 3516 void security_task_getsecid_obj(struct task_struct *p, u32 *secid) 3517 { 3518 *secid = 0; 3519 call_void_hook(task_getsecid_obj, p, secid); 3520 } 3521 EXPORT_SYMBOL(security_task_getsecid_obj); 3522 3523 /** 3524 * security_task_setnice() - Check if setting a task's nice value is allowed 3525 * @p: target task 3526 * @nice: nice value 3527 * 3528 * Check permission before setting the nice value of @p to @nice. 3529 * 3530 * Return: Returns 0 if permission is granted. 3531 */ 3532 int security_task_setnice(struct task_struct *p, int nice) 3533 { 3534 return call_int_hook(task_setnice, p, nice); 3535 } 3536 3537 /** 3538 * security_task_setioprio() - Check if setting a task's ioprio is allowed 3539 * @p: target task 3540 * @ioprio: ioprio value 3541 * 3542 * Check permission before setting the ioprio value of @p to @ioprio. 3543 * 3544 * Return: Returns 0 if permission is granted. 3545 */ 3546 int security_task_setioprio(struct task_struct *p, int ioprio) 3547 { 3548 return call_int_hook(task_setioprio, p, ioprio); 3549 } 3550 3551 /** 3552 * security_task_getioprio() - Check if getting a task's ioprio is allowed 3553 * @p: task 3554 * 3555 * Check permission before getting the ioprio value of @p. 3556 * 3557 * Return: Returns 0 if permission is granted. 3558 */ 3559 int security_task_getioprio(struct task_struct *p) 3560 { 3561 return call_int_hook(task_getioprio, p); 3562 } 3563 3564 /** 3565 * security_task_prlimit() - Check if get/setting resources limits is allowed 3566 * @cred: current task credentials 3567 * @tcred: target task credentials 3568 * @flags: LSM_PRLIMIT_* flag bits indicating a get/set/both 3569 * 3570 * Check permission before getting and/or setting the resource limits of 3571 * another task. 3572 * 3573 * Return: Returns 0 if permission is granted. 3574 */ 3575 int security_task_prlimit(const struct cred *cred, const struct cred *tcred, 3576 unsigned int flags) 3577 { 3578 return call_int_hook(task_prlimit, cred, tcred, flags); 3579 } 3580 3581 /** 3582 * security_task_setrlimit() - Check if setting a new rlimit value is allowed 3583 * @p: target task's group leader 3584 * @resource: resource whose limit is being set 3585 * @new_rlim: new resource limit 3586 * 3587 * Check permission before setting the resource limits of process @p for 3588 * @resource to @new_rlim. The old resource limit values can be examined by 3589 * dereferencing (p->signal->rlim + resource). 3590 * 3591 * Return: Returns 0 if permission is granted. 3592 */ 3593 int security_task_setrlimit(struct task_struct *p, unsigned int resource, 3594 struct rlimit *new_rlim) 3595 { 3596 return call_int_hook(task_setrlimit, p, resource, new_rlim); 3597 } 3598 3599 /** 3600 * security_task_setscheduler() - Check if setting sched policy/param is allowed 3601 * @p: target task 3602 * 3603 * Check permission before setting scheduling policy and/or parameters of 3604 * process @p. 3605 * 3606 * Return: Returns 0 if permission is granted. 3607 */ 3608 int security_task_setscheduler(struct task_struct *p) 3609 { 3610 return call_int_hook(task_setscheduler, p); 3611 } 3612 3613 /** 3614 * security_task_getscheduler() - Check if getting scheduling info is allowed 3615 * @p: target task 3616 * 3617 * Check permission before obtaining scheduling information for process @p. 3618 * 3619 * Return: Returns 0 if permission is granted. 3620 */ 3621 int security_task_getscheduler(struct task_struct *p) 3622 { 3623 return call_int_hook(task_getscheduler, p); 3624 } 3625 3626 /** 3627 * security_task_movememory() - Check if moving memory is allowed 3628 * @p: task 3629 * 3630 * Check permission before moving memory owned by process @p. 3631 * 3632 * Return: Returns 0 if permission is granted. 3633 */ 3634 int security_task_movememory(struct task_struct *p) 3635 { 3636 return call_int_hook(task_movememory, p); 3637 } 3638 3639 /** 3640 * security_task_kill() - Check if sending a signal is allowed 3641 * @p: target process 3642 * @info: signal information 3643 * @sig: signal value 3644 * @cred: credentials of the signal sender, NULL if @current 3645 * 3646 * Check permission before sending signal @sig to @p. @info can be NULL, the 3647 * constant 1, or a pointer to a kernel_siginfo structure. If @info is 1 or 3648 * SI_FROMKERNEL(info) is true, then the signal should be viewed as coming from 3649 * the kernel and should typically be permitted. SIGIO signals are handled 3650 * separately by the send_sigiotask hook in file_security_ops. 3651 * 3652 * Return: Returns 0 if permission is granted. 3653 */ 3654 int security_task_kill(struct task_struct *p, struct kernel_siginfo *info, 3655 int sig, const struct cred *cred) 3656 { 3657 return call_int_hook(task_kill, p, info, sig, cred); 3658 } 3659 3660 /** 3661 * security_task_prctl() - Check if a prctl op is allowed 3662 * @option: operation 3663 * @arg2: argument 3664 * @arg3: argument 3665 * @arg4: argument 3666 * @arg5: argument 3667 * 3668 * Check permission before performing a process control operation on the 3669 * current process. 3670 * 3671 * Return: Return -ENOSYS if no-one wanted to handle this op, any other value 3672 * to cause prctl() to return immediately with that value. 3673 */ 3674 int security_task_prctl(int option, unsigned long arg2, unsigned long arg3, 3675 unsigned long arg4, unsigned long arg5) 3676 { 3677 int thisrc; 3678 int rc = LSM_RET_DEFAULT(task_prctl); 3679 struct lsm_static_call *scall; 3680 3681 lsm_for_each_hook(scall, task_prctl) { 3682 thisrc = scall->hl->hook.task_prctl(option, arg2, arg3, arg4, arg5); 3683 if (thisrc != LSM_RET_DEFAULT(task_prctl)) { 3684 rc = thisrc; 3685 if (thisrc != 0) 3686 break; 3687 } 3688 } 3689 return rc; 3690 } 3691 3692 /** 3693 * security_task_to_inode() - Set the security attributes of a task's inode 3694 * @p: task 3695 * @inode: inode 3696 * 3697 * Set the security attributes for an inode based on an associated task's 3698 * security attributes, e.g. for /proc/pid inodes. 3699 */ 3700 void security_task_to_inode(struct task_struct *p, struct inode *inode) 3701 { 3702 call_void_hook(task_to_inode, p, inode); 3703 } 3704 3705 /** 3706 * security_create_user_ns() - Check if creating a new userns is allowed 3707 * @cred: prepared creds 3708 * 3709 * Check permission prior to creating a new user namespace. 3710 * 3711 * Return: Returns 0 if successful, otherwise < 0 error code. 3712 */ 3713 int security_create_user_ns(const struct cred *cred) 3714 { 3715 return call_int_hook(userns_create, cred); 3716 } 3717 3718 /** 3719 * security_ipc_permission() - Check if sysv ipc access is allowed 3720 * @ipcp: ipc permission structure 3721 * @flag: requested permissions 3722 * 3723 * Check permissions for access to IPC. 3724 * 3725 * Return: Returns 0 if permission is granted. 3726 */ 3727 int security_ipc_permission(struct kern_ipc_perm *ipcp, short flag) 3728 { 3729 return call_int_hook(ipc_permission, ipcp, flag); 3730 } 3731 3732 /** 3733 * security_ipc_getsecid() - Get the sysv ipc object's secid 3734 * @ipcp: ipc permission structure 3735 * @secid: secid pointer 3736 * 3737 * Get the secid associated with the ipc object. In case of failure, @secid 3738 * will be set to zero. 3739 */ 3740 void security_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid) 3741 { 3742 *secid = 0; 3743 call_void_hook(ipc_getsecid, ipcp, secid); 3744 } 3745 3746 /** 3747 * security_msg_msg_alloc() - Allocate a sysv ipc message LSM blob 3748 * @msg: message structure 3749 * 3750 * Allocate and attach a security structure to the msg->security field. The 3751 * security field is initialized to NULL when the structure is first created. 3752 * 3753 * Return: Return 0 if operation was successful and permission is granted. 3754 */ 3755 int security_msg_msg_alloc(struct msg_msg *msg) 3756 { 3757 int rc = lsm_msg_msg_alloc(msg); 3758 3759 if (unlikely(rc)) 3760 return rc; 3761 rc = call_int_hook(msg_msg_alloc_security, msg); 3762 if (unlikely(rc)) 3763 security_msg_msg_free(msg); 3764 return rc; 3765 } 3766 3767 /** 3768 * security_msg_msg_free() - Free a sysv ipc message LSM blob 3769 * @msg: message structure 3770 * 3771 * Deallocate the security structure for this message. 3772 */ 3773 void security_msg_msg_free(struct msg_msg *msg) 3774 { 3775 call_void_hook(msg_msg_free_security, msg); 3776 kfree(msg->security); 3777 msg->security = NULL; 3778 } 3779 3780 /** 3781 * security_msg_queue_alloc() - Allocate a sysv ipc msg queue LSM blob 3782 * @msq: sysv ipc permission structure 3783 * 3784 * Allocate and attach a security structure to @msg. The security field is 3785 * initialized to NULL when the structure is first created. 3786 * 3787 * Return: Returns 0 if operation was successful and permission is granted. 3788 */ 3789 int security_msg_queue_alloc(struct kern_ipc_perm *msq) 3790 { 3791 int rc = lsm_ipc_alloc(msq); 3792 3793 if (unlikely(rc)) 3794 return rc; 3795 rc = call_int_hook(msg_queue_alloc_security, msq); 3796 if (unlikely(rc)) 3797 security_msg_queue_free(msq); 3798 return rc; 3799 } 3800 3801 /** 3802 * security_msg_queue_free() - Free a sysv ipc msg queue LSM blob 3803 * @msq: sysv ipc permission structure 3804 * 3805 * Deallocate security field @perm->security for the message queue. 3806 */ 3807 void security_msg_queue_free(struct kern_ipc_perm *msq) 3808 { 3809 call_void_hook(msg_queue_free_security, msq); 3810 kfree(msq->security); 3811 msq->security = NULL; 3812 } 3813 3814 /** 3815 * security_msg_queue_associate() - Check if a msg queue operation is allowed 3816 * @msq: sysv ipc permission structure 3817 * @msqflg: operation flags 3818 * 3819 * Check permission when a message queue is requested through the msgget system 3820 * call. This hook is only called when returning the message queue identifier 3821 * for an existing message queue, not when a new message queue is created. 3822 * 3823 * Return: Return 0 if permission is granted. 3824 */ 3825 int security_msg_queue_associate(struct kern_ipc_perm *msq, int msqflg) 3826 { 3827 return call_int_hook(msg_queue_associate, msq, msqflg); 3828 } 3829 3830 /** 3831 * security_msg_queue_msgctl() - Check if a msg queue operation is allowed 3832 * @msq: sysv ipc permission structure 3833 * @cmd: operation 3834 * 3835 * Check permission when a message control operation specified by @cmd is to be 3836 * performed on the message queue with permissions. 3837 * 3838 * Return: Returns 0 if permission is granted. 3839 */ 3840 int security_msg_queue_msgctl(struct kern_ipc_perm *msq, int cmd) 3841 { 3842 return call_int_hook(msg_queue_msgctl, msq, cmd); 3843 } 3844 3845 /** 3846 * security_msg_queue_msgsnd() - Check if sending a sysv ipc message is allowed 3847 * @msq: sysv ipc permission structure 3848 * @msg: message 3849 * @msqflg: operation flags 3850 * 3851 * Check permission before a message, @msg, is enqueued on the message queue 3852 * with permissions specified in @msq. 3853 * 3854 * Return: Returns 0 if permission is granted. 3855 */ 3856 int security_msg_queue_msgsnd(struct kern_ipc_perm *msq, 3857 struct msg_msg *msg, int msqflg) 3858 { 3859 return call_int_hook(msg_queue_msgsnd, msq, msg, msqflg); 3860 } 3861 3862 /** 3863 * security_msg_queue_msgrcv() - Check if receiving a sysv ipc msg is allowed 3864 * @msq: sysv ipc permission structure 3865 * @msg: message 3866 * @target: target task 3867 * @type: type of message requested 3868 * @mode: operation flags 3869 * 3870 * Check permission before a message, @msg, is removed from the message queue. 3871 * The @target task structure contains a pointer to the process that will be 3872 * receiving the message (not equal to the current process when inline receives 3873 * are being performed). 3874 * 3875 * Return: Returns 0 if permission is granted. 3876 */ 3877 int security_msg_queue_msgrcv(struct kern_ipc_perm *msq, struct msg_msg *msg, 3878 struct task_struct *target, long type, int mode) 3879 { 3880 return call_int_hook(msg_queue_msgrcv, msq, msg, target, type, mode); 3881 } 3882 3883 /** 3884 * security_shm_alloc() - Allocate a sysv shm LSM blob 3885 * @shp: sysv ipc permission structure 3886 * 3887 * Allocate and attach a security structure to the @shp security field. The 3888 * security field is initialized to NULL when the structure is first created. 3889 * 3890 * Return: Returns 0 if operation was successful and permission is granted. 3891 */ 3892 int security_shm_alloc(struct kern_ipc_perm *shp) 3893 { 3894 int rc = lsm_ipc_alloc(shp); 3895 3896 if (unlikely(rc)) 3897 return rc; 3898 rc = call_int_hook(shm_alloc_security, shp); 3899 if (unlikely(rc)) 3900 security_shm_free(shp); 3901 return rc; 3902 } 3903 3904 /** 3905 * security_shm_free() - Free a sysv shm LSM blob 3906 * @shp: sysv ipc permission structure 3907 * 3908 * Deallocate the security structure @perm->security for the memory segment. 3909 */ 3910 void security_shm_free(struct kern_ipc_perm *shp) 3911 { 3912 call_void_hook(shm_free_security, shp); 3913 kfree(shp->security); 3914 shp->security = NULL; 3915 } 3916 3917 /** 3918 * security_shm_associate() - Check if a sysv shm operation is allowed 3919 * @shp: sysv ipc permission structure 3920 * @shmflg: operation flags 3921 * 3922 * Check permission when a shared memory region is requested through the shmget 3923 * system call. This hook is only called when returning the shared memory 3924 * region identifier for an existing region, not when a new shared memory 3925 * region is created. 3926 * 3927 * Return: Returns 0 if permission is granted. 3928 */ 3929 int security_shm_associate(struct kern_ipc_perm *shp, int shmflg) 3930 { 3931 return call_int_hook(shm_associate, shp, shmflg); 3932 } 3933 3934 /** 3935 * security_shm_shmctl() - Check if a sysv shm operation is allowed 3936 * @shp: sysv ipc permission structure 3937 * @cmd: operation 3938 * 3939 * Check permission when a shared memory control operation specified by @cmd is 3940 * to be performed on the shared memory region with permissions in @shp. 3941 * 3942 * Return: Return 0 if permission is granted. 3943 */ 3944 int security_shm_shmctl(struct kern_ipc_perm *shp, int cmd) 3945 { 3946 return call_int_hook(shm_shmctl, shp, cmd); 3947 } 3948 3949 /** 3950 * security_shm_shmat() - Check if a sysv shm attach operation is allowed 3951 * @shp: sysv ipc permission structure 3952 * @shmaddr: address of memory region to attach 3953 * @shmflg: operation flags 3954 * 3955 * Check permissions prior to allowing the shmat system call to attach the 3956 * shared memory segment with permissions @shp to the data segment of the 3957 * calling process. The attaching address is specified by @shmaddr. 3958 * 3959 * Return: Returns 0 if permission is granted. 3960 */ 3961 int security_shm_shmat(struct kern_ipc_perm *shp, 3962 char __user *shmaddr, int shmflg) 3963 { 3964 return call_int_hook(shm_shmat, shp, shmaddr, shmflg); 3965 } 3966 3967 /** 3968 * security_sem_alloc() - Allocate a sysv semaphore LSM blob 3969 * @sma: sysv ipc permission structure 3970 * 3971 * Allocate and attach a security structure to the @sma security field. The 3972 * security field is initialized to NULL when the structure is first created. 3973 * 3974 * Return: Returns 0 if operation was successful and permission is granted. 3975 */ 3976 int security_sem_alloc(struct kern_ipc_perm *sma) 3977 { 3978 int rc = lsm_ipc_alloc(sma); 3979 3980 if (unlikely(rc)) 3981 return rc; 3982 rc = call_int_hook(sem_alloc_security, sma); 3983 if (unlikely(rc)) 3984 security_sem_free(sma); 3985 return rc; 3986 } 3987 3988 /** 3989 * security_sem_free() - Free a sysv semaphore LSM blob 3990 * @sma: sysv ipc permission structure 3991 * 3992 * Deallocate security structure @sma->security for the semaphore. 3993 */ 3994 void security_sem_free(struct kern_ipc_perm *sma) 3995 { 3996 call_void_hook(sem_free_security, sma); 3997 kfree(sma->security); 3998 sma->security = NULL; 3999 } 4000 4001 /** 4002 * security_sem_associate() - Check if a sysv semaphore operation is allowed 4003 * @sma: sysv ipc permission structure 4004 * @semflg: operation flags 4005 * 4006 * Check permission when a semaphore is requested through the semget system 4007 * call. This hook is only called when returning the semaphore identifier for 4008 * an existing semaphore, not when a new one must be created. 4009 * 4010 * Return: Returns 0 if permission is granted. 4011 */ 4012 int security_sem_associate(struct kern_ipc_perm *sma, int semflg) 4013 { 4014 return call_int_hook(sem_associate, sma, semflg); 4015 } 4016 4017 /** 4018 * security_sem_semctl() - Check if a sysv semaphore operation is allowed 4019 * @sma: sysv ipc permission structure 4020 * @cmd: operation 4021 * 4022 * Check permission when a semaphore operation specified by @cmd is to be 4023 * performed on the semaphore. 4024 * 4025 * Return: Returns 0 if permission is granted. 4026 */ 4027 int security_sem_semctl(struct kern_ipc_perm *sma, int cmd) 4028 { 4029 return call_int_hook(sem_semctl, sma, cmd); 4030 } 4031 4032 /** 4033 * security_sem_semop() - Check if a sysv semaphore operation is allowed 4034 * @sma: sysv ipc permission structure 4035 * @sops: operations to perform 4036 * @nsops: number of operations 4037 * @alter: flag indicating changes will be made 4038 * 4039 * Check permissions before performing operations on members of the semaphore 4040 * set. If the @alter flag is nonzero, the semaphore set may be modified. 4041 * 4042 * Return: Returns 0 if permission is granted. 4043 */ 4044 int security_sem_semop(struct kern_ipc_perm *sma, struct sembuf *sops, 4045 unsigned nsops, int alter) 4046 { 4047 return call_int_hook(sem_semop, sma, sops, nsops, alter); 4048 } 4049 4050 /** 4051 * security_d_instantiate() - Populate an inode's LSM state based on a dentry 4052 * @dentry: dentry 4053 * @inode: inode 4054 * 4055 * Fill in @inode security information for a @dentry if allowed. 4056 */ 4057 void security_d_instantiate(struct dentry *dentry, struct inode *inode) 4058 { 4059 if (unlikely(inode && IS_PRIVATE(inode))) 4060 return; 4061 call_void_hook(d_instantiate, dentry, inode); 4062 } 4063 EXPORT_SYMBOL(security_d_instantiate); 4064 4065 /* 4066 * Please keep this in sync with it's counterpart in security/lsm_syscalls.c 4067 */ 4068 4069 /** 4070 * security_getselfattr - Read an LSM attribute of the current process. 4071 * @attr: which attribute to return 4072 * @uctx: the user-space destination for the information, or NULL 4073 * @size: pointer to the size of space available to receive the data 4074 * @flags: special handling options. LSM_FLAG_SINGLE indicates that only 4075 * attributes associated with the LSM identified in the passed @ctx be 4076 * reported. 4077 * 4078 * A NULL value for @uctx can be used to get both the number of attributes 4079 * and the size of the data. 4080 * 4081 * Returns the number of attributes found on success, negative value 4082 * on error. @size is reset to the total size of the data. 4083 * If @size is insufficient to contain the data -E2BIG is returned. 4084 */ 4085 int security_getselfattr(unsigned int attr, struct lsm_ctx __user *uctx, 4086 u32 __user *size, u32 flags) 4087 { 4088 struct lsm_static_call *scall; 4089 struct lsm_ctx lctx = { .id = LSM_ID_UNDEF, }; 4090 u8 __user *base = (u8 __user *)uctx; 4091 u32 entrysize; 4092 u32 total = 0; 4093 u32 left; 4094 bool toobig = false; 4095 bool single = false; 4096 int count = 0; 4097 int rc; 4098 4099 if (attr == LSM_ATTR_UNDEF) 4100 return -EINVAL; 4101 if (size == NULL) 4102 return -EINVAL; 4103 if (get_user(left, size)) 4104 return -EFAULT; 4105 4106 if (flags) { 4107 /* 4108 * Only flag supported is LSM_FLAG_SINGLE 4109 */ 4110 if (flags != LSM_FLAG_SINGLE || !uctx) 4111 return -EINVAL; 4112 if (copy_from_user(&lctx, uctx, sizeof(lctx))) 4113 return -EFAULT; 4114 /* 4115 * If the LSM ID isn't specified it is an error. 4116 */ 4117 if (lctx.id == LSM_ID_UNDEF) 4118 return -EINVAL; 4119 single = true; 4120 } 4121 4122 /* 4123 * In the usual case gather all the data from the LSMs. 4124 * In the single case only get the data from the LSM specified. 4125 */ 4126 lsm_for_each_hook(scall, getselfattr) { 4127 if (single && lctx.id != scall->hl->lsmid->id) 4128 continue; 4129 entrysize = left; 4130 if (base) 4131 uctx = (struct lsm_ctx __user *)(base + total); 4132 rc = scall->hl->hook.getselfattr(attr, uctx, &entrysize, flags); 4133 if (rc == -EOPNOTSUPP) { 4134 rc = 0; 4135 continue; 4136 } 4137 if (rc == -E2BIG) { 4138 rc = 0; 4139 left = 0; 4140 toobig = true; 4141 } else if (rc < 0) 4142 return rc; 4143 else 4144 left -= entrysize; 4145 4146 total += entrysize; 4147 count += rc; 4148 if (single) 4149 break; 4150 } 4151 if (put_user(total, size)) 4152 return -EFAULT; 4153 if (toobig) 4154 return -E2BIG; 4155 if (count == 0) 4156 return LSM_RET_DEFAULT(getselfattr); 4157 return count; 4158 } 4159 4160 /* 4161 * Please keep this in sync with it's counterpart in security/lsm_syscalls.c 4162 */ 4163 4164 /** 4165 * security_setselfattr - Set an LSM attribute on the current process. 4166 * @attr: which attribute to set 4167 * @uctx: the user-space source for the information 4168 * @size: the size of the data 4169 * @flags: reserved for future use, must be 0 4170 * 4171 * Set an LSM attribute for the current process. The LSM, attribute 4172 * and new value are included in @uctx. 4173 * 4174 * Returns 0 on success, -EINVAL if the input is inconsistent, -EFAULT 4175 * if the user buffer is inaccessible, E2BIG if size is too big, or an 4176 * LSM specific failure. 4177 */ 4178 int security_setselfattr(unsigned int attr, struct lsm_ctx __user *uctx, 4179 u32 size, u32 flags) 4180 { 4181 struct lsm_static_call *scall; 4182 struct lsm_ctx *lctx; 4183 int rc = LSM_RET_DEFAULT(setselfattr); 4184 u64 required_len; 4185 4186 if (flags) 4187 return -EINVAL; 4188 if (size < sizeof(*lctx)) 4189 return -EINVAL; 4190 if (size > PAGE_SIZE) 4191 return -E2BIG; 4192 4193 lctx = memdup_user(uctx, size); 4194 if (IS_ERR(lctx)) 4195 return PTR_ERR(lctx); 4196 4197 if (size < lctx->len || 4198 check_add_overflow(sizeof(*lctx), lctx->ctx_len, &required_len) || 4199 lctx->len < required_len) { 4200 rc = -EINVAL; 4201 goto free_out; 4202 } 4203 4204 lsm_for_each_hook(scall, setselfattr) 4205 if ((scall->hl->lsmid->id) == lctx->id) { 4206 rc = scall->hl->hook.setselfattr(attr, lctx, size, flags); 4207 break; 4208 } 4209 4210 free_out: 4211 kfree(lctx); 4212 return rc; 4213 } 4214 4215 /** 4216 * security_getprocattr() - Read an attribute for a task 4217 * @p: the task 4218 * @lsmid: LSM identification 4219 * @name: attribute name 4220 * @value: attribute value 4221 * 4222 * Read attribute @name for task @p and store it into @value if allowed. 4223 * 4224 * Return: Returns the length of @value on success, a negative value otherwise. 4225 */ 4226 int security_getprocattr(struct task_struct *p, int lsmid, const char *name, 4227 char **value) 4228 { 4229 struct lsm_static_call *scall; 4230 4231 lsm_for_each_hook(scall, getprocattr) { 4232 if (lsmid != 0 && lsmid != scall->hl->lsmid->id) 4233 continue; 4234 return scall->hl->hook.getprocattr(p, name, value); 4235 } 4236 return LSM_RET_DEFAULT(getprocattr); 4237 } 4238 4239 /** 4240 * security_setprocattr() - Set an attribute for a task 4241 * @lsmid: LSM identification 4242 * @name: attribute name 4243 * @value: attribute value 4244 * @size: attribute value size 4245 * 4246 * Write (set) the current task's attribute @name to @value, size @size if 4247 * allowed. 4248 * 4249 * Return: Returns bytes written on success, a negative value otherwise. 4250 */ 4251 int security_setprocattr(int lsmid, const char *name, void *value, size_t size) 4252 { 4253 struct lsm_static_call *scall; 4254 4255 lsm_for_each_hook(scall, setprocattr) { 4256 if (lsmid != 0 && lsmid != scall->hl->lsmid->id) 4257 continue; 4258 return scall->hl->hook.setprocattr(name, value, size); 4259 } 4260 return LSM_RET_DEFAULT(setprocattr); 4261 } 4262 4263 /** 4264 * security_netlink_send() - Save info and check if netlink sending is allowed 4265 * @sk: sending socket 4266 * @skb: netlink message 4267 * 4268 * Save security information for a netlink message so that permission checking 4269 * can be performed when the message is processed. The security information 4270 * can be saved using the eff_cap field of the netlink_skb_parms structure. 4271 * Also may be used to provide fine grained control over message transmission. 4272 * 4273 * Return: Returns 0 if the information was successfully saved and message is 4274 * allowed to be transmitted. 4275 */ 4276 int security_netlink_send(struct sock *sk, struct sk_buff *skb) 4277 { 4278 return call_int_hook(netlink_send, sk, skb); 4279 } 4280 4281 /** 4282 * security_ismaclabel() - Check if the named attribute is a MAC label 4283 * @name: full extended attribute name 4284 * 4285 * Check if the extended attribute specified by @name represents a MAC label. 4286 * 4287 * Return: Returns 1 if name is a MAC attribute otherwise returns 0. 4288 */ 4289 int security_ismaclabel(const char *name) 4290 { 4291 return call_int_hook(ismaclabel, name); 4292 } 4293 EXPORT_SYMBOL(security_ismaclabel); 4294 4295 /** 4296 * security_secid_to_secctx() - Convert a secid to a secctx 4297 * @secid: secid 4298 * @secdata: secctx 4299 * @seclen: secctx length 4300 * 4301 * Convert secid to security context. If @secdata is NULL the length of the 4302 * result will be returned in @seclen, but no @secdata will be returned. This 4303 * does mean that the length could change between calls to check the length and 4304 * the next call which actually allocates and returns the @secdata. 4305 * 4306 * Return: Return 0 on success, error on failure. 4307 */ 4308 int security_secid_to_secctx(u32 secid, char **secdata, u32 *seclen) 4309 { 4310 return call_int_hook(secid_to_secctx, secid, secdata, seclen); 4311 } 4312 EXPORT_SYMBOL(security_secid_to_secctx); 4313 4314 /** 4315 * security_secctx_to_secid() - Convert a secctx to a secid 4316 * @secdata: secctx 4317 * @seclen: length of secctx 4318 * @secid: secid 4319 * 4320 * Convert security context to secid. 4321 * 4322 * Return: Returns 0 on success, error on failure. 4323 */ 4324 int security_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid) 4325 { 4326 *secid = 0; 4327 return call_int_hook(secctx_to_secid, secdata, seclen, secid); 4328 } 4329 EXPORT_SYMBOL(security_secctx_to_secid); 4330 4331 /** 4332 * security_release_secctx() - Free a secctx buffer 4333 * @secdata: secctx 4334 * @seclen: length of secctx 4335 * 4336 * Release the security context. 4337 */ 4338 void security_release_secctx(char *secdata, u32 seclen) 4339 { 4340 call_void_hook(release_secctx, secdata, seclen); 4341 } 4342 EXPORT_SYMBOL(security_release_secctx); 4343 4344 /** 4345 * security_inode_invalidate_secctx() - Invalidate an inode's security label 4346 * @inode: inode 4347 * 4348 * Notify the security module that it must revalidate the security context of 4349 * an inode. 4350 */ 4351 void security_inode_invalidate_secctx(struct inode *inode) 4352 { 4353 call_void_hook(inode_invalidate_secctx, inode); 4354 } 4355 EXPORT_SYMBOL(security_inode_invalidate_secctx); 4356 4357 /** 4358 * security_inode_notifysecctx() - Notify the LSM of an inode's security label 4359 * @inode: inode 4360 * @ctx: secctx 4361 * @ctxlen: length of secctx 4362 * 4363 * Notify the security module of what the security context of an inode should 4364 * be. Initializes the incore security context managed by the security module 4365 * for this inode. Example usage: NFS client invokes this hook to initialize 4366 * the security context in its incore inode to the value provided by the server 4367 * for the file when the server returned the file's attributes to the client. 4368 * Must be called with inode->i_mutex locked. 4369 * 4370 * Return: Returns 0 on success, error on failure. 4371 */ 4372 int security_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen) 4373 { 4374 return call_int_hook(inode_notifysecctx, inode, ctx, ctxlen); 4375 } 4376 EXPORT_SYMBOL(security_inode_notifysecctx); 4377 4378 /** 4379 * security_inode_setsecctx() - Change the security label of an inode 4380 * @dentry: inode 4381 * @ctx: secctx 4382 * @ctxlen: length of secctx 4383 * 4384 * Change the security context of an inode. Updates the incore security 4385 * context managed by the security module and invokes the fs code as needed 4386 * (via __vfs_setxattr_noperm) to update any backing xattrs that represent the 4387 * context. Example usage: NFS server invokes this hook to change the security 4388 * context in its incore inode and on the backing filesystem to a value 4389 * provided by the client on a SETATTR operation. Must be called with 4390 * inode->i_mutex locked. 4391 * 4392 * Return: Returns 0 on success, error on failure. 4393 */ 4394 int security_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen) 4395 { 4396 return call_int_hook(inode_setsecctx, dentry, ctx, ctxlen); 4397 } 4398 EXPORT_SYMBOL(security_inode_setsecctx); 4399 4400 /** 4401 * security_inode_getsecctx() - Get the security label of an inode 4402 * @inode: inode 4403 * @ctx: secctx 4404 * @ctxlen: length of secctx 4405 * 4406 * On success, returns 0 and fills out @ctx and @ctxlen with the security 4407 * context for the given @inode. 4408 * 4409 * Return: Returns 0 on success, error on failure. 4410 */ 4411 int security_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen) 4412 { 4413 return call_int_hook(inode_getsecctx, inode, ctx, ctxlen); 4414 } 4415 EXPORT_SYMBOL(security_inode_getsecctx); 4416 4417 #ifdef CONFIG_WATCH_QUEUE 4418 /** 4419 * security_post_notification() - Check if a watch notification can be posted 4420 * @w_cred: credentials of the task that set the watch 4421 * @cred: credentials of the task which triggered the watch 4422 * @n: the notification 4423 * 4424 * Check to see if a watch notification can be posted to a particular queue. 4425 * 4426 * Return: Returns 0 if permission is granted. 4427 */ 4428 int security_post_notification(const struct cred *w_cred, 4429 const struct cred *cred, 4430 struct watch_notification *n) 4431 { 4432 return call_int_hook(post_notification, w_cred, cred, n); 4433 } 4434 #endif /* CONFIG_WATCH_QUEUE */ 4435 4436 #ifdef CONFIG_KEY_NOTIFICATIONS 4437 /** 4438 * security_watch_key() - Check if a task is allowed to watch for key events 4439 * @key: the key to watch 4440 * 4441 * Check to see if a process is allowed to watch for event notifications from 4442 * a key or keyring. 4443 * 4444 * Return: Returns 0 if permission is granted. 4445 */ 4446 int security_watch_key(struct key *key) 4447 { 4448 return call_int_hook(watch_key, key); 4449 } 4450 #endif /* CONFIG_KEY_NOTIFICATIONS */ 4451 4452 #ifdef CONFIG_SECURITY_NETWORK 4453 /** 4454 * security_unix_stream_connect() - Check if a AF_UNIX stream is allowed 4455 * @sock: originating sock 4456 * @other: peer sock 4457 * @newsk: new sock 4458 * 4459 * Check permissions before establishing a Unix domain stream connection 4460 * between @sock and @other. 4461 * 4462 * The @unix_stream_connect and @unix_may_send hooks were necessary because 4463 * Linux provides an alternative to the conventional file name space for Unix 4464 * domain sockets. Whereas binding and connecting to sockets in the file name 4465 * space is mediated by the typical file permissions (and caught by the mknod 4466 * and permission hooks in inode_security_ops), binding and connecting to 4467 * sockets in the abstract name space is completely unmediated. Sufficient 4468 * control of Unix domain sockets in the abstract name space isn't possible 4469 * using only the socket layer hooks, since we need to know the actual target 4470 * socket, which is not looked up until we are inside the af_unix code. 4471 * 4472 * Return: Returns 0 if permission is granted. 4473 */ 4474 int security_unix_stream_connect(struct sock *sock, struct sock *other, 4475 struct sock *newsk) 4476 { 4477 return call_int_hook(unix_stream_connect, sock, other, newsk); 4478 } 4479 EXPORT_SYMBOL(security_unix_stream_connect); 4480 4481 /** 4482 * security_unix_may_send() - Check if AF_UNIX socket can send datagrams 4483 * @sock: originating sock 4484 * @other: peer sock 4485 * 4486 * Check permissions before connecting or sending datagrams from @sock to 4487 * @other. 4488 * 4489 * The @unix_stream_connect and @unix_may_send hooks were necessary because 4490 * Linux provides an alternative to the conventional file name space for Unix 4491 * domain sockets. Whereas binding and connecting to sockets in the file name 4492 * space is mediated by the typical file permissions (and caught by the mknod 4493 * and permission hooks in inode_security_ops), binding and connecting to 4494 * sockets in the abstract name space is completely unmediated. Sufficient 4495 * control of Unix domain sockets in the abstract name space isn't possible 4496 * using only the socket layer hooks, since we need to know the actual target 4497 * socket, which is not looked up until we are inside the af_unix code. 4498 * 4499 * Return: Returns 0 if permission is granted. 4500 */ 4501 int security_unix_may_send(struct socket *sock, struct socket *other) 4502 { 4503 return call_int_hook(unix_may_send, sock, other); 4504 } 4505 EXPORT_SYMBOL(security_unix_may_send); 4506 4507 /** 4508 * security_socket_create() - Check if creating a new socket is allowed 4509 * @family: protocol family 4510 * @type: communications type 4511 * @protocol: requested protocol 4512 * @kern: set to 1 if a kernel socket is requested 4513 * 4514 * Check permissions prior to creating a new socket. 4515 * 4516 * Return: Returns 0 if permission is granted. 4517 */ 4518 int security_socket_create(int family, int type, int protocol, int kern) 4519 { 4520 return call_int_hook(socket_create, family, type, protocol, kern); 4521 } 4522 4523 /** 4524 * security_socket_post_create() - Initialize a newly created socket 4525 * @sock: socket 4526 * @family: protocol family 4527 * @type: communications type 4528 * @protocol: requested protocol 4529 * @kern: set to 1 if a kernel socket is requested 4530 * 4531 * This hook allows a module to update or allocate a per-socket security 4532 * structure. Note that the security field was not added directly to the socket 4533 * structure, but rather, the socket security information is stored in the 4534 * associated inode. Typically, the inode alloc_security hook will allocate 4535 * and attach security information to SOCK_INODE(sock)->i_security. This hook 4536 * may be used to update the SOCK_INODE(sock)->i_security field with additional 4537 * information that wasn't available when the inode was allocated. 4538 * 4539 * Return: Returns 0 if permission is granted. 4540 */ 4541 int security_socket_post_create(struct socket *sock, int family, 4542 int type, int protocol, int kern) 4543 { 4544 return call_int_hook(socket_post_create, sock, family, type, 4545 protocol, kern); 4546 } 4547 4548 /** 4549 * security_socket_socketpair() - Check if creating a socketpair is allowed 4550 * @socka: first socket 4551 * @sockb: second socket 4552 * 4553 * Check permissions before creating a fresh pair of sockets. 4554 * 4555 * Return: Returns 0 if permission is granted and the connection was 4556 * established. 4557 */ 4558 int security_socket_socketpair(struct socket *socka, struct socket *sockb) 4559 { 4560 return call_int_hook(socket_socketpair, socka, sockb); 4561 } 4562 EXPORT_SYMBOL(security_socket_socketpair); 4563 4564 /** 4565 * security_socket_bind() - Check if a socket bind operation is allowed 4566 * @sock: socket 4567 * @address: requested bind address 4568 * @addrlen: length of address 4569 * 4570 * Check permission before socket protocol layer bind operation is performed 4571 * and the socket @sock is bound to the address specified in the @address 4572 * parameter. 4573 * 4574 * Return: Returns 0 if permission is granted. 4575 */ 4576 int security_socket_bind(struct socket *sock, 4577 struct sockaddr *address, int addrlen) 4578 { 4579 return call_int_hook(socket_bind, sock, address, addrlen); 4580 } 4581 4582 /** 4583 * security_socket_connect() - Check if a socket connect operation is allowed 4584 * @sock: socket 4585 * @address: address of remote connection point 4586 * @addrlen: length of address 4587 * 4588 * Check permission before socket protocol layer connect operation attempts to 4589 * connect socket @sock to a remote address, @address. 4590 * 4591 * Return: Returns 0 if permission is granted. 4592 */ 4593 int security_socket_connect(struct socket *sock, 4594 struct sockaddr *address, int addrlen) 4595 { 4596 return call_int_hook(socket_connect, sock, address, addrlen); 4597 } 4598 4599 /** 4600 * security_socket_listen() - Check if a socket is allowed to listen 4601 * @sock: socket 4602 * @backlog: connection queue size 4603 * 4604 * Check permission before socket protocol layer listen operation. 4605 * 4606 * Return: Returns 0 if permission is granted. 4607 */ 4608 int security_socket_listen(struct socket *sock, int backlog) 4609 { 4610 return call_int_hook(socket_listen, sock, backlog); 4611 } 4612 4613 /** 4614 * security_socket_accept() - Check if a socket is allowed to accept connections 4615 * @sock: listening socket 4616 * @newsock: newly creation connection socket 4617 * 4618 * Check permission before accepting a new connection. Note that the new 4619 * socket, @newsock, has been created and some information copied to it, but 4620 * the accept operation has not actually been performed. 4621 * 4622 * Return: Returns 0 if permission is granted. 4623 */ 4624 int security_socket_accept(struct socket *sock, struct socket *newsock) 4625 { 4626 return call_int_hook(socket_accept, sock, newsock); 4627 } 4628 4629 /** 4630 * security_socket_sendmsg() - Check if sending a message is allowed 4631 * @sock: sending socket 4632 * @msg: message to send 4633 * @size: size of message 4634 * 4635 * Check permission before transmitting a message to another socket. 4636 * 4637 * Return: Returns 0 if permission is granted. 4638 */ 4639 int security_socket_sendmsg(struct socket *sock, struct msghdr *msg, int size) 4640 { 4641 return call_int_hook(socket_sendmsg, sock, msg, size); 4642 } 4643 4644 /** 4645 * security_socket_recvmsg() - Check if receiving a message is allowed 4646 * @sock: receiving socket 4647 * @msg: message to receive 4648 * @size: size of message 4649 * @flags: operational flags 4650 * 4651 * Check permission before receiving a message from a socket. 4652 * 4653 * Return: Returns 0 if permission is granted. 4654 */ 4655 int security_socket_recvmsg(struct socket *sock, struct msghdr *msg, 4656 int size, int flags) 4657 { 4658 return call_int_hook(socket_recvmsg, sock, msg, size, flags); 4659 } 4660 4661 /** 4662 * security_socket_getsockname() - Check if reading the socket addr is allowed 4663 * @sock: socket 4664 * 4665 * Check permission before reading the local address (name) of the socket 4666 * object. 4667 * 4668 * Return: Returns 0 if permission is granted. 4669 */ 4670 int security_socket_getsockname(struct socket *sock) 4671 { 4672 return call_int_hook(socket_getsockname, sock); 4673 } 4674 4675 /** 4676 * security_socket_getpeername() - Check if reading the peer's addr is allowed 4677 * @sock: socket 4678 * 4679 * Check permission before the remote address (name) of a socket object. 4680 * 4681 * Return: Returns 0 if permission is granted. 4682 */ 4683 int security_socket_getpeername(struct socket *sock) 4684 { 4685 return call_int_hook(socket_getpeername, sock); 4686 } 4687 4688 /** 4689 * security_socket_getsockopt() - Check if reading a socket option is allowed 4690 * @sock: socket 4691 * @level: option's protocol level 4692 * @optname: option name 4693 * 4694 * Check permissions before retrieving the options associated with socket 4695 * @sock. 4696 * 4697 * Return: Returns 0 if permission is granted. 4698 */ 4699 int security_socket_getsockopt(struct socket *sock, int level, int optname) 4700 { 4701 return call_int_hook(socket_getsockopt, sock, level, optname); 4702 } 4703 4704 /** 4705 * security_socket_setsockopt() - Check if setting a socket option is allowed 4706 * @sock: socket 4707 * @level: option's protocol level 4708 * @optname: option name 4709 * 4710 * Check permissions before setting the options associated with socket @sock. 4711 * 4712 * Return: Returns 0 if permission is granted. 4713 */ 4714 int security_socket_setsockopt(struct socket *sock, int level, int optname) 4715 { 4716 return call_int_hook(socket_setsockopt, sock, level, optname); 4717 } 4718 4719 /** 4720 * security_socket_shutdown() - Checks if shutting down the socket is allowed 4721 * @sock: socket 4722 * @how: flag indicating how sends and receives are handled 4723 * 4724 * Checks permission before all or part of a connection on the socket @sock is 4725 * shut down. 4726 * 4727 * Return: Returns 0 if permission is granted. 4728 */ 4729 int security_socket_shutdown(struct socket *sock, int how) 4730 { 4731 return call_int_hook(socket_shutdown, sock, how); 4732 } 4733 4734 /** 4735 * security_sock_rcv_skb() - Check if an incoming network packet is allowed 4736 * @sk: destination sock 4737 * @skb: incoming packet 4738 * 4739 * Check permissions on incoming network packets. This hook is distinct from 4740 * Netfilter's IP input hooks since it is the first time that the incoming 4741 * sk_buff @skb has been associated with a particular socket, @sk. Must not 4742 * sleep inside this hook because some callers hold spinlocks. 4743 * 4744 * Return: Returns 0 if permission is granted. 4745 */ 4746 int security_sock_rcv_skb(struct sock *sk, struct sk_buff *skb) 4747 { 4748 return call_int_hook(socket_sock_rcv_skb, sk, skb); 4749 } 4750 EXPORT_SYMBOL(security_sock_rcv_skb); 4751 4752 /** 4753 * security_socket_getpeersec_stream() - Get the remote peer label 4754 * @sock: socket 4755 * @optval: destination buffer 4756 * @optlen: size of peer label copied into the buffer 4757 * @len: maximum size of the destination buffer 4758 * 4759 * This hook allows the security module to provide peer socket security state 4760 * for unix or connected tcp sockets to userspace via getsockopt SO_GETPEERSEC. 4761 * For tcp sockets this can be meaningful if the socket is associated with an 4762 * ipsec SA. 4763 * 4764 * Return: Returns 0 if all is well, otherwise, typical getsockopt return 4765 * values. 4766 */ 4767 int security_socket_getpeersec_stream(struct socket *sock, sockptr_t optval, 4768 sockptr_t optlen, unsigned int len) 4769 { 4770 return call_int_hook(socket_getpeersec_stream, sock, optval, optlen, 4771 len); 4772 } 4773 4774 /** 4775 * security_socket_getpeersec_dgram() - Get the remote peer label 4776 * @sock: socket 4777 * @skb: datagram packet 4778 * @secid: remote peer label secid 4779 * 4780 * This hook allows the security module to provide peer socket security state 4781 * for udp sockets on a per-packet basis to userspace via getsockopt 4782 * SO_GETPEERSEC. The application must first have indicated the IP_PASSSEC 4783 * option via getsockopt. It can then retrieve the security state returned by 4784 * this hook for a packet via the SCM_SECURITY ancillary message type. 4785 * 4786 * Return: Returns 0 on success, error on failure. 4787 */ 4788 int security_socket_getpeersec_dgram(struct socket *sock, 4789 struct sk_buff *skb, u32 *secid) 4790 { 4791 return call_int_hook(socket_getpeersec_dgram, sock, skb, secid); 4792 } 4793 EXPORT_SYMBOL(security_socket_getpeersec_dgram); 4794 4795 /** 4796 * lsm_sock_alloc - allocate a composite sock blob 4797 * @sock: the sock that needs a blob 4798 * @gfp: allocation mode 4799 * 4800 * Allocate the sock blob for all the modules 4801 * 4802 * Returns 0, or -ENOMEM if memory can't be allocated. 4803 */ 4804 static int lsm_sock_alloc(struct sock *sock, gfp_t gfp) 4805 { 4806 return lsm_blob_alloc(&sock->sk_security, blob_sizes.lbs_sock, gfp); 4807 } 4808 4809 /** 4810 * security_sk_alloc() - Allocate and initialize a sock's LSM blob 4811 * @sk: sock 4812 * @family: protocol family 4813 * @priority: gfp flags 4814 * 4815 * Allocate and attach a security structure to the sk->sk_security field, which 4816 * is used to copy security attributes between local stream sockets. 4817 * 4818 * Return: Returns 0 on success, error on failure. 4819 */ 4820 int security_sk_alloc(struct sock *sk, int family, gfp_t priority) 4821 { 4822 int rc = lsm_sock_alloc(sk, priority); 4823 4824 if (unlikely(rc)) 4825 return rc; 4826 rc = call_int_hook(sk_alloc_security, sk, family, priority); 4827 if (unlikely(rc)) 4828 security_sk_free(sk); 4829 return rc; 4830 } 4831 4832 /** 4833 * security_sk_free() - Free the sock's LSM blob 4834 * @sk: sock 4835 * 4836 * Deallocate security structure. 4837 */ 4838 void security_sk_free(struct sock *sk) 4839 { 4840 call_void_hook(sk_free_security, sk); 4841 kfree(sk->sk_security); 4842 sk->sk_security = NULL; 4843 } 4844 4845 /** 4846 * security_sk_clone() - Clone a sock's LSM state 4847 * @sk: original sock 4848 * @newsk: target sock 4849 * 4850 * Clone/copy security structure. 4851 */ 4852 void security_sk_clone(const struct sock *sk, struct sock *newsk) 4853 { 4854 call_void_hook(sk_clone_security, sk, newsk); 4855 } 4856 EXPORT_SYMBOL(security_sk_clone); 4857 4858 /** 4859 * security_sk_classify_flow() - Set a flow's secid based on socket 4860 * @sk: original socket 4861 * @flic: target flow 4862 * 4863 * Set the target flow's secid to socket's secid. 4864 */ 4865 void security_sk_classify_flow(const struct sock *sk, struct flowi_common *flic) 4866 { 4867 call_void_hook(sk_getsecid, sk, &flic->flowic_secid); 4868 } 4869 EXPORT_SYMBOL(security_sk_classify_flow); 4870 4871 /** 4872 * security_req_classify_flow() - Set a flow's secid based on request_sock 4873 * @req: request_sock 4874 * @flic: target flow 4875 * 4876 * Sets @flic's secid to @req's secid. 4877 */ 4878 void security_req_classify_flow(const struct request_sock *req, 4879 struct flowi_common *flic) 4880 { 4881 call_void_hook(req_classify_flow, req, flic); 4882 } 4883 EXPORT_SYMBOL(security_req_classify_flow); 4884 4885 /** 4886 * security_sock_graft() - Reconcile LSM state when grafting a sock on a socket 4887 * @sk: sock being grafted 4888 * @parent: target parent socket 4889 * 4890 * Sets @parent's inode secid to @sk's secid and update @sk with any necessary 4891 * LSM state from @parent. 4892 */ 4893 void security_sock_graft(struct sock *sk, struct socket *parent) 4894 { 4895 call_void_hook(sock_graft, sk, parent); 4896 } 4897 EXPORT_SYMBOL(security_sock_graft); 4898 4899 /** 4900 * security_inet_conn_request() - Set request_sock state using incoming connect 4901 * @sk: parent listening sock 4902 * @skb: incoming connection 4903 * @req: new request_sock 4904 * 4905 * Initialize the @req LSM state based on @sk and the incoming connect in @skb. 4906 * 4907 * Return: Returns 0 if permission is granted. 4908 */ 4909 int security_inet_conn_request(const struct sock *sk, 4910 struct sk_buff *skb, struct request_sock *req) 4911 { 4912 return call_int_hook(inet_conn_request, sk, skb, req); 4913 } 4914 EXPORT_SYMBOL(security_inet_conn_request); 4915 4916 /** 4917 * security_inet_csk_clone() - Set new sock LSM state based on request_sock 4918 * @newsk: new sock 4919 * @req: connection request_sock 4920 * 4921 * Set that LSM state of @sock using the LSM state from @req. 4922 */ 4923 void security_inet_csk_clone(struct sock *newsk, 4924 const struct request_sock *req) 4925 { 4926 call_void_hook(inet_csk_clone, newsk, req); 4927 } 4928 4929 /** 4930 * security_inet_conn_established() - Update sock's LSM state with connection 4931 * @sk: sock 4932 * @skb: connection packet 4933 * 4934 * Update @sock's LSM state to represent a new connection from @skb. 4935 */ 4936 void security_inet_conn_established(struct sock *sk, 4937 struct sk_buff *skb) 4938 { 4939 call_void_hook(inet_conn_established, sk, skb); 4940 } 4941 EXPORT_SYMBOL(security_inet_conn_established); 4942 4943 /** 4944 * security_secmark_relabel_packet() - Check if setting a secmark is allowed 4945 * @secid: new secmark value 4946 * 4947 * Check if the process should be allowed to relabel packets to @secid. 4948 * 4949 * Return: Returns 0 if permission is granted. 4950 */ 4951 int security_secmark_relabel_packet(u32 secid) 4952 { 4953 return call_int_hook(secmark_relabel_packet, secid); 4954 } 4955 EXPORT_SYMBOL(security_secmark_relabel_packet); 4956 4957 /** 4958 * security_secmark_refcount_inc() - Increment the secmark labeling rule count 4959 * 4960 * Tells the LSM to increment the number of secmark labeling rules loaded. 4961 */ 4962 void security_secmark_refcount_inc(void) 4963 { 4964 call_void_hook(secmark_refcount_inc); 4965 } 4966 EXPORT_SYMBOL(security_secmark_refcount_inc); 4967 4968 /** 4969 * security_secmark_refcount_dec() - Decrement the secmark labeling rule count 4970 * 4971 * Tells the LSM to decrement the number of secmark labeling rules loaded. 4972 */ 4973 void security_secmark_refcount_dec(void) 4974 { 4975 call_void_hook(secmark_refcount_dec); 4976 } 4977 EXPORT_SYMBOL(security_secmark_refcount_dec); 4978 4979 /** 4980 * security_tun_dev_alloc_security() - Allocate a LSM blob for a TUN device 4981 * @security: pointer to the LSM blob 4982 * 4983 * This hook allows a module to allocate a security structure for a TUN device, 4984 * returning the pointer in @security. 4985 * 4986 * Return: Returns a zero on success, negative values on failure. 4987 */ 4988 int security_tun_dev_alloc_security(void **security) 4989 { 4990 int rc; 4991 4992 rc = lsm_blob_alloc(security, blob_sizes.lbs_tun_dev, GFP_KERNEL); 4993 if (rc) 4994 return rc; 4995 4996 rc = call_int_hook(tun_dev_alloc_security, *security); 4997 if (rc) { 4998 kfree(*security); 4999 *security = NULL; 5000 } 5001 return rc; 5002 } 5003 EXPORT_SYMBOL(security_tun_dev_alloc_security); 5004 5005 /** 5006 * security_tun_dev_free_security() - Free a TUN device LSM blob 5007 * @security: LSM blob 5008 * 5009 * This hook allows a module to free the security structure for a TUN device. 5010 */ 5011 void security_tun_dev_free_security(void *security) 5012 { 5013 kfree(security); 5014 } 5015 EXPORT_SYMBOL(security_tun_dev_free_security); 5016 5017 /** 5018 * security_tun_dev_create() - Check if creating a TUN device is allowed 5019 * 5020 * Check permissions prior to creating a new TUN device. 5021 * 5022 * Return: Returns 0 if permission is granted. 5023 */ 5024 int security_tun_dev_create(void) 5025 { 5026 return call_int_hook(tun_dev_create); 5027 } 5028 EXPORT_SYMBOL(security_tun_dev_create); 5029 5030 /** 5031 * security_tun_dev_attach_queue() - Check if attaching a TUN queue is allowed 5032 * @security: TUN device LSM blob 5033 * 5034 * Check permissions prior to attaching to a TUN device queue. 5035 * 5036 * Return: Returns 0 if permission is granted. 5037 */ 5038 int security_tun_dev_attach_queue(void *security) 5039 { 5040 return call_int_hook(tun_dev_attach_queue, security); 5041 } 5042 EXPORT_SYMBOL(security_tun_dev_attach_queue); 5043 5044 /** 5045 * security_tun_dev_attach() - Update TUN device LSM state on attach 5046 * @sk: associated sock 5047 * @security: TUN device LSM blob 5048 * 5049 * This hook can be used by the module to update any security state associated 5050 * with the TUN device's sock structure. 5051 * 5052 * Return: Returns 0 if permission is granted. 5053 */ 5054 int security_tun_dev_attach(struct sock *sk, void *security) 5055 { 5056 return call_int_hook(tun_dev_attach, sk, security); 5057 } 5058 EXPORT_SYMBOL(security_tun_dev_attach); 5059 5060 /** 5061 * security_tun_dev_open() - Update TUN device LSM state on open 5062 * @security: TUN device LSM blob 5063 * 5064 * This hook can be used by the module to update any security state associated 5065 * with the TUN device's security structure. 5066 * 5067 * Return: Returns 0 if permission is granted. 5068 */ 5069 int security_tun_dev_open(void *security) 5070 { 5071 return call_int_hook(tun_dev_open, security); 5072 } 5073 EXPORT_SYMBOL(security_tun_dev_open); 5074 5075 /** 5076 * security_sctp_assoc_request() - Update the LSM on a SCTP association req 5077 * @asoc: SCTP association 5078 * @skb: packet requesting the association 5079 * 5080 * Passes the @asoc and @chunk->skb of the association INIT packet to the LSM. 5081 * 5082 * Return: Returns 0 on success, error on failure. 5083 */ 5084 int security_sctp_assoc_request(struct sctp_association *asoc, 5085 struct sk_buff *skb) 5086 { 5087 return call_int_hook(sctp_assoc_request, asoc, skb); 5088 } 5089 EXPORT_SYMBOL(security_sctp_assoc_request); 5090 5091 /** 5092 * security_sctp_bind_connect() - Validate a list of addrs for a SCTP option 5093 * @sk: socket 5094 * @optname: SCTP option to validate 5095 * @address: list of IP addresses to validate 5096 * @addrlen: length of the address list 5097 * 5098 * Validiate permissions required for each address associated with sock @sk. 5099 * Depending on @optname, the addresses will be treated as either a connect or 5100 * bind service. The @addrlen is calculated on each IPv4 and IPv6 address using 5101 * sizeof(struct sockaddr_in) or sizeof(struct sockaddr_in6). 5102 * 5103 * Return: Returns 0 on success, error on failure. 5104 */ 5105 int security_sctp_bind_connect(struct sock *sk, int optname, 5106 struct sockaddr *address, int addrlen) 5107 { 5108 return call_int_hook(sctp_bind_connect, sk, optname, address, addrlen); 5109 } 5110 EXPORT_SYMBOL(security_sctp_bind_connect); 5111 5112 /** 5113 * security_sctp_sk_clone() - Clone a SCTP sock's LSM state 5114 * @asoc: SCTP association 5115 * @sk: original sock 5116 * @newsk: target sock 5117 * 5118 * Called whenever a new socket is created by accept(2) (i.e. a TCP style 5119 * socket) or when a socket is 'peeled off' e.g userspace calls 5120 * sctp_peeloff(3). 5121 */ 5122 void security_sctp_sk_clone(struct sctp_association *asoc, struct sock *sk, 5123 struct sock *newsk) 5124 { 5125 call_void_hook(sctp_sk_clone, asoc, sk, newsk); 5126 } 5127 EXPORT_SYMBOL(security_sctp_sk_clone); 5128 5129 /** 5130 * security_sctp_assoc_established() - Update LSM state when assoc established 5131 * @asoc: SCTP association 5132 * @skb: packet establishing the association 5133 * 5134 * Passes the @asoc and @chunk->skb of the association COOKIE_ACK packet to the 5135 * security module. 5136 * 5137 * Return: Returns 0 if permission is granted. 5138 */ 5139 int security_sctp_assoc_established(struct sctp_association *asoc, 5140 struct sk_buff *skb) 5141 { 5142 return call_int_hook(sctp_assoc_established, asoc, skb); 5143 } 5144 EXPORT_SYMBOL(security_sctp_assoc_established); 5145 5146 /** 5147 * security_mptcp_add_subflow() - Inherit the LSM label from the MPTCP socket 5148 * @sk: the owning MPTCP socket 5149 * @ssk: the new subflow 5150 * 5151 * Update the labeling for the given MPTCP subflow, to match the one of the 5152 * owning MPTCP socket. This hook has to be called after the socket creation and 5153 * initialization via the security_socket_create() and 5154 * security_socket_post_create() LSM hooks. 5155 * 5156 * Return: Returns 0 on success or a negative error code on failure. 5157 */ 5158 int security_mptcp_add_subflow(struct sock *sk, struct sock *ssk) 5159 { 5160 return call_int_hook(mptcp_add_subflow, sk, ssk); 5161 } 5162 5163 #endif /* CONFIG_SECURITY_NETWORK */ 5164 5165 #ifdef CONFIG_SECURITY_INFINIBAND 5166 /** 5167 * security_ib_pkey_access() - Check if access to an IB pkey is allowed 5168 * @sec: LSM blob 5169 * @subnet_prefix: subnet prefix of the port 5170 * @pkey: IB pkey 5171 * 5172 * Check permission to access a pkey when modifying a QP. 5173 * 5174 * Return: Returns 0 if permission is granted. 5175 */ 5176 int security_ib_pkey_access(void *sec, u64 subnet_prefix, u16 pkey) 5177 { 5178 return call_int_hook(ib_pkey_access, sec, subnet_prefix, pkey); 5179 } 5180 EXPORT_SYMBOL(security_ib_pkey_access); 5181 5182 /** 5183 * security_ib_endport_manage_subnet() - Check if SMPs traffic is allowed 5184 * @sec: LSM blob 5185 * @dev_name: IB device name 5186 * @port_num: port number 5187 * 5188 * Check permissions to send and receive SMPs on a end port. 5189 * 5190 * Return: Returns 0 if permission is granted. 5191 */ 5192 int security_ib_endport_manage_subnet(void *sec, 5193 const char *dev_name, u8 port_num) 5194 { 5195 return call_int_hook(ib_endport_manage_subnet, sec, dev_name, port_num); 5196 } 5197 EXPORT_SYMBOL(security_ib_endport_manage_subnet); 5198 5199 /** 5200 * security_ib_alloc_security() - Allocate an Infiniband LSM blob 5201 * @sec: LSM blob 5202 * 5203 * Allocate a security structure for Infiniband objects. 5204 * 5205 * Return: Returns 0 on success, non-zero on failure. 5206 */ 5207 int security_ib_alloc_security(void **sec) 5208 { 5209 int rc; 5210 5211 rc = lsm_blob_alloc(sec, blob_sizes.lbs_ib, GFP_KERNEL); 5212 if (rc) 5213 return rc; 5214 5215 rc = call_int_hook(ib_alloc_security, *sec); 5216 if (rc) { 5217 kfree(*sec); 5218 *sec = NULL; 5219 } 5220 return rc; 5221 } 5222 EXPORT_SYMBOL(security_ib_alloc_security); 5223 5224 /** 5225 * security_ib_free_security() - Free an Infiniband LSM blob 5226 * @sec: LSM blob 5227 * 5228 * Deallocate an Infiniband security structure. 5229 */ 5230 void security_ib_free_security(void *sec) 5231 { 5232 kfree(sec); 5233 } 5234 EXPORT_SYMBOL(security_ib_free_security); 5235 #endif /* CONFIG_SECURITY_INFINIBAND */ 5236 5237 #ifdef CONFIG_SECURITY_NETWORK_XFRM 5238 /** 5239 * security_xfrm_policy_alloc() - Allocate a xfrm policy LSM blob 5240 * @ctxp: xfrm security context being added to the SPD 5241 * @sec_ctx: security label provided by userspace 5242 * @gfp: gfp flags 5243 * 5244 * Allocate a security structure to the xp->security field; the security field 5245 * is initialized to NULL when the xfrm_policy is allocated. 5246 * 5247 * Return: Return 0 if operation was successful. 5248 */ 5249 int security_xfrm_policy_alloc(struct xfrm_sec_ctx **ctxp, 5250 struct xfrm_user_sec_ctx *sec_ctx, 5251 gfp_t gfp) 5252 { 5253 return call_int_hook(xfrm_policy_alloc_security, ctxp, sec_ctx, gfp); 5254 } 5255 EXPORT_SYMBOL(security_xfrm_policy_alloc); 5256 5257 /** 5258 * security_xfrm_policy_clone() - Clone xfrm policy LSM state 5259 * @old_ctx: xfrm security context 5260 * @new_ctxp: target xfrm security context 5261 * 5262 * Allocate a security structure in new_ctxp that contains the information from 5263 * the old_ctx structure. 5264 * 5265 * Return: Return 0 if operation was successful. 5266 */ 5267 int security_xfrm_policy_clone(struct xfrm_sec_ctx *old_ctx, 5268 struct xfrm_sec_ctx **new_ctxp) 5269 { 5270 return call_int_hook(xfrm_policy_clone_security, old_ctx, new_ctxp); 5271 } 5272 5273 /** 5274 * security_xfrm_policy_free() - Free a xfrm security context 5275 * @ctx: xfrm security context 5276 * 5277 * Free LSM resources associated with @ctx. 5278 */ 5279 void security_xfrm_policy_free(struct xfrm_sec_ctx *ctx) 5280 { 5281 call_void_hook(xfrm_policy_free_security, ctx); 5282 } 5283 EXPORT_SYMBOL(security_xfrm_policy_free); 5284 5285 /** 5286 * security_xfrm_policy_delete() - Check if deleting a xfrm policy is allowed 5287 * @ctx: xfrm security context 5288 * 5289 * Authorize deletion of a SPD entry. 5290 * 5291 * Return: Returns 0 if permission is granted. 5292 */ 5293 int security_xfrm_policy_delete(struct xfrm_sec_ctx *ctx) 5294 { 5295 return call_int_hook(xfrm_policy_delete_security, ctx); 5296 } 5297 5298 /** 5299 * security_xfrm_state_alloc() - Allocate a xfrm state LSM blob 5300 * @x: xfrm state being added to the SAD 5301 * @sec_ctx: security label provided by userspace 5302 * 5303 * Allocate a security structure to the @x->security field; the security field 5304 * is initialized to NULL when the xfrm_state is allocated. Set the context to 5305 * correspond to @sec_ctx. 5306 * 5307 * Return: Return 0 if operation was successful. 5308 */ 5309 int security_xfrm_state_alloc(struct xfrm_state *x, 5310 struct xfrm_user_sec_ctx *sec_ctx) 5311 { 5312 return call_int_hook(xfrm_state_alloc, x, sec_ctx); 5313 } 5314 EXPORT_SYMBOL(security_xfrm_state_alloc); 5315 5316 /** 5317 * security_xfrm_state_alloc_acquire() - Allocate a xfrm state LSM blob 5318 * @x: xfrm state being added to the SAD 5319 * @polsec: associated policy's security context 5320 * @secid: secid from the flow 5321 * 5322 * Allocate a security structure to the x->security field; the security field 5323 * is initialized to NULL when the xfrm_state is allocated. Set the context to 5324 * correspond to secid. 5325 * 5326 * Return: Returns 0 if operation was successful. 5327 */ 5328 int security_xfrm_state_alloc_acquire(struct xfrm_state *x, 5329 struct xfrm_sec_ctx *polsec, u32 secid) 5330 { 5331 return call_int_hook(xfrm_state_alloc_acquire, x, polsec, secid); 5332 } 5333 5334 /** 5335 * security_xfrm_state_delete() - Check if deleting a xfrm state is allowed 5336 * @x: xfrm state 5337 * 5338 * Authorize deletion of x->security. 5339 * 5340 * Return: Returns 0 if permission is granted. 5341 */ 5342 int security_xfrm_state_delete(struct xfrm_state *x) 5343 { 5344 return call_int_hook(xfrm_state_delete_security, x); 5345 } 5346 EXPORT_SYMBOL(security_xfrm_state_delete); 5347 5348 /** 5349 * security_xfrm_state_free() - Free a xfrm state 5350 * @x: xfrm state 5351 * 5352 * Deallocate x->security. 5353 */ 5354 void security_xfrm_state_free(struct xfrm_state *x) 5355 { 5356 call_void_hook(xfrm_state_free_security, x); 5357 } 5358 5359 /** 5360 * security_xfrm_policy_lookup() - Check if using a xfrm policy is allowed 5361 * @ctx: target xfrm security context 5362 * @fl_secid: flow secid used to authorize access 5363 * 5364 * Check permission when a flow selects a xfrm_policy for processing XFRMs on a 5365 * packet. The hook is called when selecting either a per-socket policy or a 5366 * generic xfrm policy. 5367 * 5368 * Return: Return 0 if permission is granted, -ESRCH otherwise, or -errno on 5369 * other errors. 5370 */ 5371 int security_xfrm_policy_lookup(struct xfrm_sec_ctx *ctx, u32 fl_secid) 5372 { 5373 return call_int_hook(xfrm_policy_lookup, ctx, fl_secid); 5374 } 5375 5376 /** 5377 * security_xfrm_state_pol_flow_match() - Check for a xfrm match 5378 * @x: xfrm state to match 5379 * @xp: xfrm policy to check for a match 5380 * @flic: flow to check for a match. 5381 * 5382 * Check @xp and @flic for a match with @x. 5383 * 5384 * Return: Returns 1 if there is a match. 5385 */ 5386 int security_xfrm_state_pol_flow_match(struct xfrm_state *x, 5387 struct xfrm_policy *xp, 5388 const struct flowi_common *flic) 5389 { 5390 struct lsm_static_call *scall; 5391 int rc = LSM_RET_DEFAULT(xfrm_state_pol_flow_match); 5392 5393 /* 5394 * Since this function is expected to return 0 or 1, the judgment 5395 * becomes difficult if multiple LSMs supply this call. Fortunately, 5396 * we can use the first LSM's judgment because currently only SELinux 5397 * supplies this call. 5398 * 5399 * For speed optimization, we explicitly break the loop rather than 5400 * using the macro 5401 */ 5402 lsm_for_each_hook(scall, xfrm_state_pol_flow_match) { 5403 rc = scall->hl->hook.xfrm_state_pol_flow_match(x, xp, flic); 5404 break; 5405 } 5406 return rc; 5407 } 5408 5409 /** 5410 * security_xfrm_decode_session() - Determine the xfrm secid for a packet 5411 * @skb: xfrm packet 5412 * @secid: secid 5413 * 5414 * Decode the packet in @skb and return the security label in @secid. 5415 * 5416 * Return: Return 0 if all xfrms used have the same secid. 5417 */ 5418 int security_xfrm_decode_session(struct sk_buff *skb, u32 *secid) 5419 { 5420 return call_int_hook(xfrm_decode_session, skb, secid, 1); 5421 } 5422 5423 void security_skb_classify_flow(struct sk_buff *skb, struct flowi_common *flic) 5424 { 5425 int rc = call_int_hook(xfrm_decode_session, skb, &flic->flowic_secid, 5426 0); 5427 5428 BUG_ON(rc); 5429 } 5430 EXPORT_SYMBOL(security_skb_classify_flow); 5431 #endif /* CONFIG_SECURITY_NETWORK_XFRM */ 5432 5433 #ifdef CONFIG_KEYS 5434 /** 5435 * security_key_alloc() - Allocate and initialize a kernel key LSM blob 5436 * @key: key 5437 * @cred: credentials 5438 * @flags: allocation flags 5439 * 5440 * Permit allocation of a key and assign security data. Note that key does not 5441 * have a serial number assigned at this point. 5442 * 5443 * Return: Return 0 if permission is granted, -ve error otherwise. 5444 */ 5445 int security_key_alloc(struct key *key, const struct cred *cred, 5446 unsigned long flags) 5447 { 5448 int rc = lsm_key_alloc(key); 5449 5450 if (unlikely(rc)) 5451 return rc; 5452 rc = call_int_hook(key_alloc, key, cred, flags); 5453 if (unlikely(rc)) 5454 security_key_free(key); 5455 return rc; 5456 } 5457 5458 /** 5459 * security_key_free() - Free a kernel key LSM blob 5460 * @key: key 5461 * 5462 * Notification of destruction; free security data. 5463 */ 5464 void security_key_free(struct key *key) 5465 { 5466 kfree(key->security); 5467 key->security = NULL; 5468 } 5469 5470 /** 5471 * security_key_permission() - Check if a kernel key operation is allowed 5472 * @key_ref: key reference 5473 * @cred: credentials of actor requesting access 5474 * @need_perm: requested permissions 5475 * 5476 * See whether a specific operational right is granted to a process on a key. 5477 * 5478 * Return: Return 0 if permission is granted, -ve error otherwise. 5479 */ 5480 int security_key_permission(key_ref_t key_ref, const struct cred *cred, 5481 enum key_need_perm need_perm) 5482 { 5483 return call_int_hook(key_permission, key_ref, cred, need_perm); 5484 } 5485 5486 /** 5487 * security_key_getsecurity() - Get the key's security label 5488 * @key: key 5489 * @buffer: security label buffer 5490 * 5491 * Get a textual representation of the security context attached to a key for 5492 * the purposes of honouring KEYCTL_GETSECURITY. This function allocates the 5493 * storage for the NUL-terminated string and the caller should free it. 5494 * 5495 * Return: Returns the length of @buffer (including terminating NUL) or -ve if 5496 * an error occurs. May also return 0 (and a NULL buffer pointer) if 5497 * there is no security label assigned to the key. 5498 */ 5499 int security_key_getsecurity(struct key *key, char **buffer) 5500 { 5501 *buffer = NULL; 5502 return call_int_hook(key_getsecurity, key, buffer); 5503 } 5504 5505 /** 5506 * security_key_post_create_or_update() - Notification of key create or update 5507 * @keyring: keyring to which the key is linked to 5508 * @key: created or updated key 5509 * @payload: data used to instantiate or update the key 5510 * @payload_len: length of payload 5511 * @flags: key flags 5512 * @create: flag indicating whether the key was created or updated 5513 * 5514 * Notify the caller of a key creation or update. 5515 */ 5516 void security_key_post_create_or_update(struct key *keyring, struct key *key, 5517 const void *payload, size_t payload_len, 5518 unsigned long flags, bool create) 5519 { 5520 call_void_hook(key_post_create_or_update, keyring, key, payload, 5521 payload_len, flags, create); 5522 } 5523 #endif /* CONFIG_KEYS */ 5524 5525 #ifdef CONFIG_AUDIT 5526 /** 5527 * security_audit_rule_init() - Allocate and init an LSM audit rule struct 5528 * @field: audit action 5529 * @op: rule operator 5530 * @rulestr: rule context 5531 * @lsmrule: receive buffer for audit rule struct 5532 * @gfp: GFP flag used for kmalloc 5533 * 5534 * Allocate and initialize an LSM audit rule structure. 5535 * 5536 * Return: Return 0 if @lsmrule has been successfully set, -EINVAL in case of 5537 * an invalid rule. 5538 */ 5539 int security_audit_rule_init(u32 field, u32 op, char *rulestr, void **lsmrule, 5540 gfp_t gfp) 5541 { 5542 return call_int_hook(audit_rule_init, field, op, rulestr, lsmrule, gfp); 5543 } 5544 5545 /** 5546 * security_audit_rule_known() - Check if an audit rule contains LSM fields 5547 * @krule: audit rule 5548 * 5549 * Specifies whether given @krule contains any fields related to the current 5550 * LSM. 5551 * 5552 * Return: Returns 1 in case of relation found, 0 otherwise. 5553 */ 5554 int security_audit_rule_known(struct audit_krule *krule) 5555 { 5556 return call_int_hook(audit_rule_known, krule); 5557 } 5558 5559 /** 5560 * security_audit_rule_free() - Free an LSM audit rule struct 5561 * @lsmrule: audit rule struct 5562 * 5563 * Deallocate the LSM audit rule structure previously allocated by 5564 * audit_rule_init(). 5565 */ 5566 void security_audit_rule_free(void *lsmrule) 5567 { 5568 call_void_hook(audit_rule_free, lsmrule); 5569 } 5570 5571 /** 5572 * security_audit_rule_match() - Check if a label matches an audit rule 5573 * @secid: security label 5574 * @field: LSM audit field 5575 * @op: matching operator 5576 * @lsmrule: audit rule 5577 * 5578 * Determine if given @secid matches a rule previously approved by 5579 * security_audit_rule_known(). 5580 * 5581 * Return: Returns 1 if secid matches the rule, 0 if it does not, -ERRNO on 5582 * failure. 5583 */ 5584 int security_audit_rule_match(u32 secid, u32 field, u32 op, void *lsmrule) 5585 { 5586 return call_int_hook(audit_rule_match, secid, field, op, lsmrule); 5587 } 5588 #endif /* CONFIG_AUDIT */ 5589 5590 #ifdef CONFIG_BPF_SYSCALL 5591 /** 5592 * security_bpf() - Check if the bpf syscall operation is allowed 5593 * @cmd: command 5594 * @attr: bpf attribute 5595 * @size: size 5596 * 5597 * Do a initial check for all bpf syscalls after the attribute is copied into 5598 * the kernel. The actual security module can implement their own rules to 5599 * check the specific cmd they need. 5600 * 5601 * Return: Returns 0 if permission is granted. 5602 */ 5603 int security_bpf(int cmd, union bpf_attr *attr, unsigned int size) 5604 { 5605 return call_int_hook(bpf, cmd, attr, size); 5606 } 5607 5608 /** 5609 * security_bpf_map() - Check if access to a bpf map is allowed 5610 * @map: bpf map 5611 * @fmode: mode 5612 * 5613 * Do a check when the kernel generates and returns a file descriptor for eBPF 5614 * maps. 5615 * 5616 * Return: Returns 0 if permission is granted. 5617 */ 5618 int security_bpf_map(struct bpf_map *map, fmode_t fmode) 5619 { 5620 return call_int_hook(bpf_map, map, fmode); 5621 } 5622 5623 /** 5624 * security_bpf_prog() - Check if access to a bpf program is allowed 5625 * @prog: bpf program 5626 * 5627 * Do a check when the kernel generates and returns a file descriptor for eBPF 5628 * programs. 5629 * 5630 * Return: Returns 0 if permission is granted. 5631 */ 5632 int security_bpf_prog(struct bpf_prog *prog) 5633 { 5634 return call_int_hook(bpf_prog, prog); 5635 } 5636 5637 /** 5638 * security_bpf_map_create() - Check if BPF map creation is allowed 5639 * @map: BPF map object 5640 * @attr: BPF syscall attributes used to create BPF map 5641 * @token: BPF token used to grant user access 5642 * 5643 * Do a check when the kernel creates a new BPF map. This is also the 5644 * point where LSM blob is allocated for LSMs that need them. 5645 * 5646 * Return: Returns 0 on success, error on failure. 5647 */ 5648 int security_bpf_map_create(struct bpf_map *map, union bpf_attr *attr, 5649 struct bpf_token *token) 5650 { 5651 return call_int_hook(bpf_map_create, map, attr, token); 5652 } 5653 5654 /** 5655 * security_bpf_prog_load() - Check if loading of BPF program is allowed 5656 * @prog: BPF program object 5657 * @attr: BPF syscall attributes used to create BPF program 5658 * @token: BPF token used to grant user access to BPF subsystem 5659 * 5660 * Perform an access control check when the kernel loads a BPF program and 5661 * allocates associated BPF program object. This hook is also responsible for 5662 * allocating any required LSM state for the BPF program. 5663 * 5664 * Return: Returns 0 on success, error on failure. 5665 */ 5666 int security_bpf_prog_load(struct bpf_prog *prog, union bpf_attr *attr, 5667 struct bpf_token *token) 5668 { 5669 return call_int_hook(bpf_prog_load, prog, attr, token); 5670 } 5671 5672 /** 5673 * security_bpf_token_create() - Check if creating of BPF token is allowed 5674 * @token: BPF token object 5675 * @attr: BPF syscall attributes used to create BPF token 5676 * @path: path pointing to BPF FS mount point from which BPF token is created 5677 * 5678 * Do a check when the kernel instantiates a new BPF token object from BPF FS 5679 * instance. This is also the point where LSM blob can be allocated for LSMs. 5680 * 5681 * Return: Returns 0 on success, error on failure. 5682 */ 5683 int security_bpf_token_create(struct bpf_token *token, union bpf_attr *attr, 5684 const struct path *path) 5685 { 5686 return call_int_hook(bpf_token_create, token, attr, path); 5687 } 5688 5689 /** 5690 * security_bpf_token_cmd() - Check if BPF token is allowed to delegate 5691 * requested BPF syscall command 5692 * @token: BPF token object 5693 * @cmd: BPF syscall command requested to be delegated by BPF token 5694 * 5695 * Do a check when the kernel decides whether provided BPF token should allow 5696 * delegation of requested BPF syscall command. 5697 * 5698 * Return: Returns 0 on success, error on failure. 5699 */ 5700 int security_bpf_token_cmd(const struct bpf_token *token, enum bpf_cmd cmd) 5701 { 5702 return call_int_hook(bpf_token_cmd, token, cmd); 5703 } 5704 5705 /** 5706 * security_bpf_token_capable() - Check if BPF token is allowed to delegate 5707 * requested BPF-related capability 5708 * @token: BPF token object 5709 * @cap: capabilities requested to be delegated by BPF token 5710 * 5711 * Do a check when the kernel decides whether provided BPF token should allow 5712 * delegation of requested BPF-related capabilities. 5713 * 5714 * Return: Returns 0 on success, error on failure. 5715 */ 5716 int security_bpf_token_capable(const struct bpf_token *token, int cap) 5717 { 5718 return call_int_hook(bpf_token_capable, token, cap); 5719 } 5720 5721 /** 5722 * security_bpf_map_free() - Free a bpf map's LSM blob 5723 * @map: bpf map 5724 * 5725 * Clean up the security information stored inside bpf map. 5726 */ 5727 void security_bpf_map_free(struct bpf_map *map) 5728 { 5729 call_void_hook(bpf_map_free, map); 5730 } 5731 5732 /** 5733 * security_bpf_prog_free() - Free a BPF program's LSM blob 5734 * @prog: BPF program struct 5735 * 5736 * Clean up the security information stored inside BPF program. 5737 */ 5738 void security_bpf_prog_free(struct bpf_prog *prog) 5739 { 5740 call_void_hook(bpf_prog_free, prog); 5741 } 5742 5743 /** 5744 * security_bpf_token_free() - Free a BPF token's LSM blob 5745 * @token: BPF token struct 5746 * 5747 * Clean up the security information stored inside BPF token. 5748 */ 5749 void security_bpf_token_free(struct bpf_token *token) 5750 { 5751 call_void_hook(bpf_token_free, token); 5752 } 5753 #endif /* CONFIG_BPF_SYSCALL */ 5754 5755 /** 5756 * security_locked_down() - Check if a kernel feature is allowed 5757 * @what: requested kernel feature 5758 * 5759 * Determine whether a kernel feature that potentially enables arbitrary code 5760 * execution in kernel space should be permitted. 5761 * 5762 * Return: Returns 0 if permission is granted. 5763 */ 5764 int security_locked_down(enum lockdown_reason what) 5765 { 5766 return call_int_hook(locked_down, what); 5767 } 5768 EXPORT_SYMBOL(security_locked_down); 5769 5770 /** 5771 * security_bdev_alloc() - Allocate a block device LSM blob 5772 * @bdev: block device 5773 * 5774 * Allocate and attach a security structure to @bdev->bd_security. The 5775 * security field is initialized to NULL when the bdev structure is 5776 * allocated. 5777 * 5778 * Return: Return 0 if operation was successful. 5779 */ 5780 int security_bdev_alloc(struct block_device *bdev) 5781 { 5782 int rc = 0; 5783 5784 rc = lsm_bdev_alloc(bdev); 5785 if (unlikely(rc)) 5786 return rc; 5787 5788 rc = call_int_hook(bdev_alloc_security, bdev); 5789 if (unlikely(rc)) 5790 security_bdev_free(bdev); 5791 5792 return rc; 5793 } 5794 EXPORT_SYMBOL(security_bdev_alloc); 5795 5796 /** 5797 * security_bdev_free() - Free a block device's LSM blob 5798 * @bdev: block device 5799 * 5800 * Deallocate the bdev security structure and set @bdev->bd_security to NULL. 5801 */ 5802 void security_bdev_free(struct block_device *bdev) 5803 { 5804 if (!bdev->bd_security) 5805 return; 5806 5807 call_void_hook(bdev_free_security, bdev); 5808 5809 kfree(bdev->bd_security); 5810 bdev->bd_security = NULL; 5811 } 5812 EXPORT_SYMBOL(security_bdev_free); 5813 5814 /** 5815 * security_bdev_setintegrity() - Set the device's integrity data 5816 * @bdev: block device 5817 * @type: type of integrity, e.g. hash digest, signature, etc 5818 * @value: the integrity value 5819 * @size: size of the integrity value 5820 * 5821 * Register a verified integrity measurement of a bdev with LSMs. 5822 * LSMs should free the previously saved data if @value is NULL. 5823 * Please note that the new hook should be invoked every time the security 5824 * information is updated to keep these data current. For example, in dm-verity, 5825 * if the mapping table is reloaded and configured to use a different dm-verity 5826 * target with a new roothash and signing information, the previously stored 5827 * data in the LSM blob will become obsolete. It is crucial to re-invoke the 5828 * hook to refresh these data and ensure they are up to date. This necessity 5829 * arises from the design of device-mapper, where a device-mapper device is 5830 * first created, and then targets are subsequently loaded into it. These 5831 * targets can be modified multiple times during the device's lifetime. 5832 * Therefore, while the LSM blob is allocated during the creation of the block 5833 * device, its actual contents are not initialized at this stage and can change 5834 * substantially over time. This includes alterations from data that the LSMs 5835 * 'trusts' to those they do not, making it essential to handle these changes 5836 * correctly. Failure to address this dynamic aspect could potentially allow 5837 * for bypassing LSM checks. 5838 * 5839 * Return: Returns 0 on success, negative values on failure. 5840 */ 5841 int security_bdev_setintegrity(struct block_device *bdev, 5842 enum lsm_integrity_type type, const void *value, 5843 size_t size) 5844 { 5845 return call_int_hook(bdev_setintegrity, bdev, type, value, size); 5846 } 5847 EXPORT_SYMBOL(security_bdev_setintegrity); 5848 5849 #ifdef CONFIG_PERF_EVENTS 5850 /** 5851 * security_perf_event_open() - Check if a perf event open is allowed 5852 * @attr: perf event attribute 5853 * @type: type of event 5854 * 5855 * Check whether the @type of perf_event_open syscall is allowed. 5856 * 5857 * Return: Returns 0 if permission is granted. 5858 */ 5859 int security_perf_event_open(struct perf_event_attr *attr, int type) 5860 { 5861 return call_int_hook(perf_event_open, attr, type); 5862 } 5863 5864 /** 5865 * security_perf_event_alloc() - Allocate a perf event LSM blob 5866 * @event: perf event 5867 * 5868 * Allocate and save perf_event security info. 5869 * 5870 * Return: Returns 0 on success, error on failure. 5871 */ 5872 int security_perf_event_alloc(struct perf_event *event) 5873 { 5874 int rc; 5875 5876 rc = lsm_blob_alloc(&event->security, blob_sizes.lbs_perf_event, 5877 GFP_KERNEL); 5878 if (rc) 5879 return rc; 5880 5881 rc = call_int_hook(perf_event_alloc, event); 5882 if (rc) { 5883 kfree(event->security); 5884 event->security = NULL; 5885 } 5886 return rc; 5887 } 5888 5889 /** 5890 * security_perf_event_free() - Free a perf event LSM blob 5891 * @event: perf event 5892 * 5893 * Release (free) perf_event security info. 5894 */ 5895 void security_perf_event_free(struct perf_event *event) 5896 { 5897 kfree(event->security); 5898 event->security = NULL; 5899 } 5900 5901 /** 5902 * security_perf_event_read() - Check if reading a perf event label is allowed 5903 * @event: perf event 5904 * 5905 * Read perf_event security info if allowed. 5906 * 5907 * Return: Returns 0 if permission is granted. 5908 */ 5909 int security_perf_event_read(struct perf_event *event) 5910 { 5911 return call_int_hook(perf_event_read, event); 5912 } 5913 5914 /** 5915 * security_perf_event_write() - Check if writing a perf event label is allowed 5916 * @event: perf event 5917 * 5918 * Write perf_event security info if allowed. 5919 * 5920 * Return: Returns 0 if permission is granted. 5921 */ 5922 int security_perf_event_write(struct perf_event *event) 5923 { 5924 return call_int_hook(perf_event_write, event); 5925 } 5926 #endif /* CONFIG_PERF_EVENTS */ 5927 5928 #ifdef CONFIG_IO_URING 5929 /** 5930 * security_uring_override_creds() - Check if overriding creds is allowed 5931 * @new: new credentials 5932 * 5933 * Check if the current task, executing an io_uring operation, is allowed to 5934 * override it's credentials with @new. 5935 * 5936 * Return: Returns 0 if permission is granted. 5937 */ 5938 int security_uring_override_creds(const struct cred *new) 5939 { 5940 return call_int_hook(uring_override_creds, new); 5941 } 5942 5943 /** 5944 * security_uring_sqpoll() - Check if IORING_SETUP_SQPOLL is allowed 5945 * 5946 * Check whether the current task is allowed to spawn a io_uring polling thread 5947 * (IORING_SETUP_SQPOLL). 5948 * 5949 * Return: Returns 0 if permission is granted. 5950 */ 5951 int security_uring_sqpoll(void) 5952 { 5953 return call_int_hook(uring_sqpoll); 5954 } 5955 5956 /** 5957 * security_uring_cmd() - Check if a io_uring passthrough command is allowed 5958 * @ioucmd: command 5959 * 5960 * Check whether the file_operations uring_cmd is allowed to run. 5961 * 5962 * Return: Returns 0 if permission is granted. 5963 */ 5964 int security_uring_cmd(struct io_uring_cmd *ioucmd) 5965 { 5966 return call_int_hook(uring_cmd, ioucmd); 5967 } 5968 #endif /* CONFIG_IO_URING */ 5969 5970 /** 5971 * security_initramfs_populated() - Notify LSMs that initramfs has been loaded 5972 * 5973 * Tells the LSMs the initramfs has been unpacked into the rootfs. 5974 */ 5975 void security_initramfs_populated(void) 5976 { 5977 call_void_hook(initramfs_populated); 5978 } 5979