1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * Security plug functions 4 * 5 * Copyright (C) 2001 WireX Communications, Inc <chris@wirex.com> 6 * Copyright (C) 2001-2002 Greg Kroah-Hartman <greg@kroah.com> 7 * Copyright (C) 2001 Networks Associates Technology, Inc <ssmalley@nai.com> 8 * Copyright (C) 2016 Mellanox Technologies 9 * Copyright (C) 2023 Microsoft Corporation <paul@paul-moore.com> 10 */ 11 12 #define pr_fmt(fmt) "LSM: " fmt 13 14 #include <linux/bpf.h> 15 #include <linux/capability.h> 16 #include <linux/dcache.h> 17 #include <linux/export.h> 18 #include <linux/init.h> 19 #include <linux/kernel.h> 20 #include <linux/kernel_read_file.h> 21 #include <linux/lsm_hooks.h> 22 #include <linux/mman.h> 23 #include <linux/mount.h> 24 #include <linux/personality.h> 25 #include <linux/backing-dev.h> 26 #include <linux/string.h> 27 #include <linux/xattr.h> 28 #include <linux/msg.h> 29 #include <linux/overflow.h> 30 #include <linux/perf_event.h> 31 #include <linux/fs.h> 32 #include <net/flow.h> 33 #include <net/sock.h> 34 35 #define SECURITY_HOOK_ACTIVE_KEY(HOOK, IDX) security_hook_active_##HOOK##_##IDX 36 37 /* 38 * Identifier for the LSM static calls. 39 * HOOK is an LSM hook as defined in linux/lsm_hookdefs.h 40 * IDX is the index of the static call. 0 <= NUM < MAX_LSM_COUNT 41 */ 42 #define LSM_STATIC_CALL(HOOK, IDX) lsm_static_call_##HOOK##_##IDX 43 44 /* 45 * Call the macro M for each LSM hook MAX_LSM_COUNT times. 46 */ 47 #define LSM_LOOP_UNROLL(M, ...) \ 48 do { \ 49 UNROLL(MAX_LSM_COUNT, M, __VA_ARGS__) \ 50 } while (0) 51 52 #define LSM_DEFINE_UNROLL(M, ...) UNROLL(MAX_LSM_COUNT, M, __VA_ARGS__) 53 54 /* 55 * These are descriptions of the reasons that can be passed to the 56 * security_locked_down() LSM hook. Placing this array here allows 57 * all security modules to use the same descriptions for auditing 58 * purposes. 59 */ 60 const char *const lockdown_reasons[LOCKDOWN_CONFIDENTIALITY_MAX + 1] = { 61 [LOCKDOWN_NONE] = "none", 62 [LOCKDOWN_MODULE_SIGNATURE] = "unsigned module loading", 63 [LOCKDOWN_DEV_MEM] = "/dev/mem,kmem,port", 64 [LOCKDOWN_EFI_TEST] = "/dev/efi_test access", 65 [LOCKDOWN_KEXEC] = "kexec of unsigned images", 66 [LOCKDOWN_HIBERNATION] = "hibernation", 67 [LOCKDOWN_PCI_ACCESS] = "direct PCI access", 68 [LOCKDOWN_IOPORT] = "raw io port access", 69 [LOCKDOWN_MSR] = "raw MSR access", 70 [LOCKDOWN_ACPI_TABLES] = "modifying ACPI tables", 71 [LOCKDOWN_DEVICE_TREE] = "modifying device tree contents", 72 [LOCKDOWN_PCMCIA_CIS] = "direct PCMCIA CIS storage", 73 [LOCKDOWN_TIOCSSERIAL] = "reconfiguration of serial port IO", 74 [LOCKDOWN_MODULE_PARAMETERS] = "unsafe module parameters", 75 [LOCKDOWN_MMIOTRACE] = "unsafe mmio", 76 [LOCKDOWN_DEBUGFS] = "debugfs access", 77 [LOCKDOWN_XMON_WR] = "xmon write access", 78 [LOCKDOWN_BPF_WRITE_USER] = "use of bpf to write user RAM", 79 [LOCKDOWN_DBG_WRITE_KERNEL] = "use of kgdb/kdb to write kernel RAM", 80 [LOCKDOWN_RTAS_ERROR_INJECTION] = "RTAS error injection", 81 [LOCKDOWN_INTEGRITY_MAX] = "integrity", 82 [LOCKDOWN_KCORE] = "/proc/kcore access", 83 [LOCKDOWN_KPROBES] = "use of kprobes", 84 [LOCKDOWN_BPF_READ_KERNEL] = "use of bpf to read kernel RAM", 85 [LOCKDOWN_DBG_READ_KERNEL] = "use of kgdb/kdb to read kernel RAM", 86 [LOCKDOWN_PERF] = "unsafe use of perf", 87 [LOCKDOWN_TRACEFS] = "use of tracefs", 88 [LOCKDOWN_XMON_RW] = "xmon read and write access", 89 [LOCKDOWN_XFRM_SECRET] = "xfrm SA secret", 90 [LOCKDOWN_CONFIDENTIALITY_MAX] = "confidentiality", 91 }; 92 93 static BLOCKING_NOTIFIER_HEAD(blocking_lsm_notifier_chain); 94 95 static struct kmem_cache *lsm_file_cache; 96 static struct kmem_cache *lsm_inode_cache; 97 98 char *lsm_names; 99 static struct lsm_blob_sizes blob_sizes __ro_after_init; 100 101 /* Boot-time LSM user choice */ 102 static __initdata const char *chosen_lsm_order; 103 static __initdata const char *chosen_major_lsm; 104 105 static __initconst const char *const builtin_lsm_order = CONFIG_LSM; 106 107 /* Ordered list of LSMs to initialize. */ 108 static __initdata struct lsm_info *ordered_lsms[MAX_LSM_COUNT + 1]; 109 static __initdata struct lsm_info *exclusive; 110 111 #ifdef CONFIG_HAVE_STATIC_CALL 112 #define LSM_HOOK_TRAMP(NAME, NUM) \ 113 &STATIC_CALL_TRAMP(LSM_STATIC_CALL(NAME, NUM)) 114 #else 115 #define LSM_HOOK_TRAMP(NAME, NUM) NULL 116 #endif 117 118 /* 119 * Define static calls and static keys for each LSM hook. 120 */ 121 #define DEFINE_LSM_STATIC_CALL(NUM, NAME, RET, ...) \ 122 DEFINE_STATIC_CALL_NULL(LSM_STATIC_CALL(NAME, NUM), \ 123 *((RET(*)(__VA_ARGS__))NULL)); \ 124 DEFINE_STATIC_KEY_FALSE(SECURITY_HOOK_ACTIVE_KEY(NAME, NUM)); 125 126 #define LSM_HOOK(RET, DEFAULT, NAME, ...) \ 127 LSM_DEFINE_UNROLL(DEFINE_LSM_STATIC_CALL, NAME, RET, __VA_ARGS__) 128 #include <linux/lsm_hook_defs.h> 129 #undef LSM_HOOK 130 #undef DEFINE_LSM_STATIC_CALL 131 132 /* 133 * Initialise a table of static calls for each LSM hook. 134 * DEFINE_STATIC_CALL_NULL invocation above generates a key (STATIC_CALL_KEY) 135 * and a trampoline (STATIC_CALL_TRAMP) which are used to call 136 * __static_call_update when updating the static call. 137 * 138 * The static calls table is used by early LSMs, some architectures can fault on 139 * unaligned accesses and the fault handling code may not be ready by then. 140 * Thus, the static calls table should be aligned to avoid any unhandled faults 141 * in early init. 142 */ 143 struct lsm_static_calls_table 144 static_calls_table __ro_after_init __aligned(sizeof(u64)) = { 145 #define INIT_LSM_STATIC_CALL(NUM, NAME) \ 146 (struct lsm_static_call) { \ 147 .key = &STATIC_CALL_KEY(LSM_STATIC_CALL(NAME, NUM)), \ 148 .trampoline = LSM_HOOK_TRAMP(NAME, NUM), \ 149 .active = &SECURITY_HOOK_ACTIVE_KEY(NAME, NUM), \ 150 }, 151 #define LSM_HOOK(RET, DEFAULT, NAME, ...) \ 152 .NAME = { \ 153 LSM_DEFINE_UNROLL(INIT_LSM_STATIC_CALL, NAME) \ 154 }, 155 #include <linux/lsm_hook_defs.h> 156 #undef LSM_HOOK 157 #undef INIT_LSM_STATIC_CALL 158 }; 159 160 static __initdata bool debug; 161 #define init_debug(...) \ 162 do { \ 163 if (debug) \ 164 pr_info(__VA_ARGS__); \ 165 } while (0) 166 167 static bool __init is_enabled(struct lsm_info *lsm) 168 { 169 if (!lsm->enabled) 170 return false; 171 172 return *lsm->enabled; 173 } 174 175 /* Mark an LSM's enabled flag. */ 176 static int lsm_enabled_true __initdata = 1; 177 static int lsm_enabled_false __initdata = 0; 178 static void __init set_enabled(struct lsm_info *lsm, bool enabled) 179 { 180 /* 181 * When an LSM hasn't configured an enable variable, we can use 182 * a hard-coded location for storing the default enabled state. 183 */ 184 if (!lsm->enabled) { 185 if (enabled) 186 lsm->enabled = &lsm_enabled_true; 187 else 188 lsm->enabled = &lsm_enabled_false; 189 } else if (lsm->enabled == &lsm_enabled_true) { 190 if (!enabled) 191 lsm->enabled = &lsm_enabled_false; 192 } else if (lsm->enabled == &lsm_enabled_false) { 193 if (enabled) 194 lsm->enabled = &lsm_enabled_true; 195 } else { 196 *lsm->enabled = enabled; 197 } 198 } 199 200 /* Is an LSM already listed in the ordered LSMs list? */ 201 static bool __init exists_ordered_lsm(struct lsm_info *lsm) 202 { 203 struct lsm_info **check; 204 205 for (check = ordered_lsms; *check; check++) 206 if (*check == lsm) 207 return true; 208 209 return false; 210 } 211 212 /* Append an LSM to the list of ordered LSMs to initialize. */ 213 static int last_lsm __initdata; 214 static void __init append_ordered_lsm(struct lsm_info *lsm, const char *from) 215 { 216 /* Ignore duplicate selections. */ 217 if (exists_ordered_lsm(lsm)) 218 return; 219 220 if (WARN(last_lsm == MAX_LSM_COUNT, "%s: out of LSM static calls!?\n", from)) 221 return; 222 223 /* Enable this LSM, if it is not already set. */ 224 if (!lsm->enabled) 225 lsm->enabled = &lsm_enabled_true; 226 ordered_lsms[last_lsm++] = lsm; 227 228 init_debug("%s ordered: %s (%s)\n", from, lsm->name, 229 is_enabled(lsm) ? "enabled" : "disabled"); 230 } 231 232 /* Is an LSM allowed to be initialized? */ 233 static bool __init lsm_allowed(struct lsm_info *lsm) 234 { 235 /* Skip if the LSM is disabled. */ 236 if (!is_enabled(lsm)) 237 return false; 238 239 /* Not allowed if another exclusive LSM already initialized. */ 240 if ((lsm->flags & LSM_FLAG_EXCLUSIVE) && exclusive) { 241 init_debug("exclusive disabled: %s\n", lsm->name); 242 return false; 243 } 244 245 return true; 246 } 247 248 static void __init lsm_set_blob_size(int *need, int *lbs) 249 { 250 int offset; 251 252 if (*need <= 0) 253 return; 254 255 offset = ALIGN(*lbs, sizeof(void *)); 256 *lbs = offset + *need; 257 *need = offset; 258 } 259 260 static void __init lsm_set_blob_sizes(struct lsm_blob_sizes *needed) 261 { 262 if (!needed) 263 return; 264 265 lsm_set_blob_size(&needed->lbs_cred, &blob_sizes.lbs_cred); 266 lsm_set_blob_size(&needed->lbs_file, &blob_sizes.lbs_file); 267 lsm_set_blob_size(&needed->lbs_ib, &blob_sizes.lbs_ib); 268 /* 269 * The inode blob gets an rcu_head in addition to 270 * what the modules might need. 271 */ 272 if (needed->lbs_inode && blob_sizes.lbs_inode == 0) 273 blob_sizes.lbs_inode = sizeof(struct rcu_head); 274 lsm_set_blob_size(&needed->lbs_inode, &blob_sizes.lbs_inode); 275 lsm_set_blob_size(&needed->lbs_ipc, &blob_sizes.lbs_ipc); 276 lsm_set_blob_size(&needed->lbs_key, &blob_sizes.lbs_key); 277 lsm_set_blob_size(&needed->lbs_msg_msg, &blob_sizes.lbs_msg_msg); 278 lsm_set_blob_size(&needed->lbs_perf_event, &blob_sizes.lbs_perf_event); 279 lsm_set_blob_size(&needed->lbs_sock, &blob_sizes.lbs_sock); 280 lsm_set_blob_size(&needed->lbs_superblock, &blob_sizes.lbs_superblock); 281 lsm_set_blob_size(&needed->lbs_task, &blob_sizes.lbs_task); 282 lsm_set_blob_size(&needed->lbs_tun_dev, &blob_sizes.lbs_tun_dev); 283 lsm_set_blob_size(&needed->lbs_xattr_count, 284 &blob_sizes.lbs_xattr_count); 285 lsm_set_blob_size(&needed->lbs_bdev, &blob_sizes.lbs_bdev); 286 } 287 288 /* Prepare LSM for initialization. */ 289 static void __init prepare_lsm(struct lsm_info *lsm) 290 { 291 int enabled = lsm_allowed(lsm); 292 293 /* Record enablement (to handle any following exclusive LSMs). */ 294 set_enabled(lsm, enabled); 295 296 /* If enabled, do pre-initialization work. */ 297 if (enabled) { 298 if ((lsm->flags & LSM_FLAG_EXCLUSIVE) && !exclusive) { 299 exclusive = lsm; 300 init_debug("exclusive chosen: %s\n", lsm->name); 301 } 302 303 lsm_set_blob_sizes(lsm->blobs); 304 } 305 } 306 307 /* Initialize a given LSM, if it is enabled. */ 308 static void __init initialize_lsm(struct lsm_info *lsm) 309 { 310 if (is_enabled(lsm)) { 311 int ret; 312 313 init_debug("initializing %s\n", lsm->name); 314 ret = lsm->init(); 315 WARN(ret, "%s failed to initialize: %d\n", lsm->name, ret); 316 } 317 } 318 319 /* 320 * Current index to use while initializing the lsm id list. 321 */ 322 u32 lsm_active_cnt __ro_after_init; 323 const struct lsm_id *lsm_idlist[MAX_LSM_COUNT]; 324 325 /* Populate ordered LSMs list from comma-separated LSM name list. */ 326 static void __init ordered_lsm_parse(const char *order, const char *origin) 327 { 328 struct lsm_info *lsm; 329 char *sep, *name, *next; 330 331 /* LSM_ORDER_FIRST is always first. */ 332 for (lsm = __start_lsm_info; lsm < __end_lsm_info; lsm++) { 333 if (lsm->order == LSM_ORDER_FIRST) 334 append_ordered_lsm(lsm, " first"); 335 } 336 337 /* Process "security=", if given. */ 338 if (chosen_major_lsm) { 339 struct lsm_info *major; 340 341 /* 342 * To match the original "security=" behavior, this 343 * explicitly does NOT fallback to another Legacy Major 344 * if the selected one was separately disabled: disable 345 * all non-matching Legacy Major LSMs. 346 */ 347 for (major = __start_lsm_info; major < __end_lsm_info; 348 major++) { 349 if ((major->flags & LSM_FLAG_LEGACY_MAJOR) && 350 strcmp(major->name, chosen_major_lsm) != 0) { 351 set_enabled(major, false); 352 init_debug("security=%s disabled: %s (only one legacy major LSM)\n", 353 chosen_major_lsm, major->name); 354 } 355 } 356 } 357 358 sep = kstrdup(order, GFP_KERNEL); 359 next = sep; 360 /* Walk the list, looking for matching LSMs. */ 361 while ((name = strsep(&next, ",")) != NULL) { 362 bool found = false; 363 364 for (lsm = __start_lsm_info; lsm < __end_lsm_info; lsm++) { 365 if (strcmp(lsm->name, name) == 0) { 366 if (lsm->order == LSM_ORDER_MUTABLE) 367 append_ordered_lsm(lsm, origin); 368 found = true; 369 } 370 } 371 372 if (!found) 373 init_debug("%s ignored: %s (not built into kernel)\n", 374 origin, name); 375 } 376 377 /* Process "security=", if given. */ 378 if (chosen_major_lsm) { 379 for (lsm = __start_lsm_info; lsm < __end_lsm_info; lsm++) { 380 if (exists_ordered_lsm(lsm)) 381 continue; 382 if (strcmp(lsm->name, chosen_major_lsm) == 0) 383 append_ordered_lsm(lsm, "security="); 384 } 385 } 386 387 /* LSM_ORDER_LAST is always last. */ 388 for (lsm = __start_lsm_info; lsm < __end_lsm_info; lsm++) { 389 if (lsm->order == LSM_ORDER_LAST) 390 append_ordered_lsm(lsm, " last"); 391 } 392 393 /* Disable all LSMs not in the ordered list. */ 394 for (lsm = __start_lsm_info; lsm < __end_lsm_info; lsm++) { 395 if (exists_ordered_lsm(lsm)) 396 continue; 397 set_enabled(lsm, false); 398 init_debug("%s skipped: %s (not in requested order)\n", 399 origin, lsm->name); 400 } 401 402 kfree(sep); 403 } 404 405 static void __init lsm_static_call_init(struct security_hook_list *hl) 406 { 407 struct lsm_static_call *scall = hl->scalls; 408 int i; 409 410 for (i = 0; i < MAX_LSM_COUNT; i++) { 411 /* Update the first static call that is not used yet */ 412 if (!scall->hl) { 413 __static_call_update(scall->key, scall->trampoline, 414 hl->hook.lsm_func_addr); 415 scall->hl = hl; 416 static_branch_enable(scall->active); 417 return; 418 } 419 scall++; 420 } 421 panic("%s - Ran out of static slots.\n", __func__); 422 } 423 424 static void __init lsm_early_cred(struct cred *cred); 425 static void __init lsm_early_task(struct task_struct *task); 426 427 static int lsm_append(const char *new, char **result); 428 429 static void __init report_lsm_order(void) 430 { 431 struct lsm_info **lsm, *early; 432 int first = 0; 433 434 pr_info("initializing lsm="); 435 436 /* Report each enabled LSM name, comma separated. */ 437 for (early = __start_early_lsm_info; 438 early < __end_early_lsm_info; early++) 439 if (is_enabled(early)) 440 pr_cont("%s%s", first++ == 0 ? "" : ",", early->name); 441 for (lsm = ordered_lsms; *lsm; lsm++) 442 if (is_enabled(*lsm)) 443 pr_cont("%s%s", first++ == 0 ? "" : ",", (*lsm)->name); 444 445 pr_cont("\n"); 446 } 447 448 static void __init ordered_lsm_init(void) 449 { 450 struct lsm_info **lsm; 451 452 if (chosen_lsm_order) { 453 if (chosen_major_lsm) { 454 pr_warn("security=%s is ignored because it is superseded by lsm=%s\n", 455 chosen_major_lsm, chosen_lsm_order); 456 chosen_major_lsm = NULL; 457 } 458 ordered_lsm_parse(chosen_lsm_order, "cmdline"); 459 } else 460 ordered_lsm_parse(builtin_lsm_order, "builtin"); 461 462 for (lsm = ordered_lsms; *lsm; lsm++) 463 prepare_lsm(*lsm); 464 465 report_lsm_order(); 466 467 init_debug("cred blob size = %d\n", blob_sizes.lbs_cred); 468 init_debug("file blob size = %d\n", blob_sizes.lbs_file); 469 init_debug("ib blob size = %d\n", blob_sizes.lbs_ib); 470 init_debug("inode blob size = %d\n", blob_sizes.lbs_inode); 471 init_debug("ipc blob size = %d\n", blob_sizes.lbs_ipc); 472 #ifdef CONFIG_KEYS 473 init_debug("key blob size = %d\n", blob_sizes.lbs_key); 474 #endif /* CONFIG_KEYS */ 475 init_debug("msg_msg blob size = %d\n", blob_sizes.lbs_msg_msg); 476 init_debug("sock blob size = %d\n", blob_sizes.lbs_sock); 477 init_debug("superblock blob size = %d\n", blob_sizes.lbs_superblock); 478 init_debug("perf event blob size = %d\n", blob_sizes.lbs_perf_event); 479 init_debug("task blob size = %d\n", blob_sizes.lbs_task); 480 init_debug("tun device blob size = %d\n", blob_sizes.lbs_tun_dev); 481 init_debug("xattr slots = %d\n", blob_sizes.lbs_xattr_count); 482 init_debug("bdev blob size = %d\n", blob_sizes.lbs_bdev); 483 484 /* 485 * Create any kmem_caches needed for blobs 486 */ 487 if (blob_sizes.lbs_file) 488 lsm_file_cache = kmem_cache_create("lsm_file_cache", 489 blob_sizes.lbs_file, 0, 490 SLAB_PANIC, NULL); 491 if (blob_sizes.lbs_inode) 492 lsm_inode_cache = kmem_cache_create("lsm_inode_cache", 493 blob_sizes.lbs_inode, 0, 494 SLAB_PANIC, NULL); 495 496 lsm_early_cred((struct cred *) current->cred); 497 lsm_early_task(current); 498 for (lsm = ordered_lsms; *lsm; lsm++) 499 initialize_lsm(*lsm); 500 } 501 502 int __init early_security_init(void) 503 { 504 struct lsm_info *lsm; 505 506 for (lsm = __start_early_lsm_info; lsm < __end_early_lsm_info; lsm++) { 507 if (!lsm->enabled) 508 lsm->enabled = &lsm_enabled_true; 509 prepare_lsm(lsm); 510 initialize_lsm(lsm); 511 } 512 513 return 0; 514 } 515 516 /** 517 * security_init - initializes the security framework 518 * 519 * This should be called early in the kernel initialization sequence. 520 */ 521 int __init security_init(void) 522 { 523 struct lsm_info *lsm; 524 525 init_debug("legacy security=%s\n", chosen_major_lsm ? : " *unspecified*"); 526 init_debug(" CONFIG_LSM=%s\n", builtin_lsm_order); 527 init_debug("boot arg lsm=%s\n", chosen_lsm_order ? : " *unspecified*"); 528 529 /* 530 * Append the names of the early LSM modules now that kmalloc() is 531 * available 532 */ 533 for (lsm = __start_early_lsm_info; lsm < __end_early_lsm_info; lsm++) { 534 init_debug(" early started: %s (%s)\n", lsm->name, 535 is_enabled(lsm) ? "enabled" : "disabled"); 536 if (lsm->enabled) 537 lsm_append(lsm->name, &lsm_names); 538 } 539 540 /* Load LSMs in specified order. */ 541 ordered_lsm_init(); 542 543 return 0; 544 } 545 546 /* Save user chosen LSM */ 547 static int __init choose_major_lsm(char *str) 548 { 549 chosen_major_lsm = str; 550 return 1; 551 } 552 __setup("security=", choose_major_lsm); 553 554 /* Explicitly choose LSM initialization order. */ 555 static int __init choose_lsm_order(char *str) 556 { 557 chosen_lsm_order = str; 558 return 1; 559 } 560 __setup("lsm=", choose_lsm_order); 561 562 /* Enable LSM order debugging. */ 563 static int __init enable_debug(char *str) 564 { 565 debug = true; 566 return 1; 567 } 568 __setup("lsm.debug", enable_debug); 569 570 static bool match_last_lsm(const char *list, const char *lsm) 571 { 572 const char *last; 573 574 if (WARN_ON(!list || !lsm)) 575 return false; 576 last = strrchr(list, ','); 577 if (last) 578 /* Pass the comma, strcmp() will check for '\0' */ 579 last++; 580 else 581 last = list; 582 return !strcmp(last, lsm); 583 } 584 585 static int lsm_append(const char *new, char **result) 586 { 587 char *cp; 588 589 if (*result == NULL) { 590 *result = kstrdup(new, GFP_KERNEL); 591 if (*result == NULL) 592 return -ENOMEM; 593 } else { 594 /* Check if it is the last registered name */ 595 if (match_last_lsm(*result, new)) 596 return 0; 597 cp = kasprintf(GFP_KERNEL, "%s,%s", *result, new); 598 if (cp == NULL) 599 return -ENOMEM; 600 kfree(*result); 601 *result = cp; 602 } 603 return 0; 604 } 605 606 /** 607 * security_add_hooks - Add a modules hooks to the hook lists. 608 * @hooks: the hooks to add 609 * @count: the number of hooks to add 610 * @lsmid: the identification information for the security module 611 * 612 * Each LSM has to register its hooks with the infrastructure. 613 */ 614 void __init security_add_hooks(struct security_hook_list *hooks, int count, 615 const struct lsm_id *lsmid) 616 { 617 int i; 618 619 /* 620 * A security module may call security_add_hooks() more 621 * than once during initialization, and LSM initialization 622 * is serialized. Landlock is one such case. 623 * Look at the previous entry, if there is one, for duplication. 624 */ 625 if (lsm_active_cnt == 0 || lsm_idlist[lsm_active_cnt - 1] != lsmid) { 626 if (lsm_active_cnt >= MAX_LSM_COUNT) 627 panic("%s Too many LSMs registered.\n", __func__); 628 lsm_idlist[lsm_active_cnt++] = lsmid; 629 } 630 631 for (i = 0; i < count; i++) { 632 hooks[i].lsmid = lsmid; 633 lsm_static_call_init(&hooks[i]); 634 } 635 636 /* 637 * Don't try to append during early_security_init(), we'll come back 638 * and fix this up afterwards. 639 */ 640 if (slab_is_available()) { 641 if (lsm_append(lsmid->name, &lsm_names) < 0) 642 panic("%s - Cannot get early memory.\n", __func__); 643 } 644 } 645 646 int call_blocking_lsm_notifier(enum lsm_event event, void *data) 647 { 648 return blocking_notifier_call_chain(&blocking_lsm_notifier_chain, 649 event, data); 650 } 651 EXPORT_SYMBOL(call_blocking_lsm_notifier); 652 653 int register_blocking_lsm_notifier(struct notifier_block *nb) 654 { 655 return blocking_notifier_chain_register(&blocking_lsm_notifier_chain, 656 nb); 657 } 658 EXPORT_SYMBOL(register_blocking_lsm_notifier); 659 660 int unregister_blocking_lsm_notifier(struct notifier_block *nb) 661 { 662 return blocking_notifier_chain_unregister(&blocking_lsm_notifier_chain, 663 nb); 664 } 665 EXPORT_SYMBOL(unregister_blocking_lsm_notifier); 666 667 /** 668 * lsm_blob_alloc - allocate a composite blob 669 * @dest: the destination for the blob 670 * @size: the size of the blob 671 * @gfp: allocation type 672 * 673 * Allocate a blob for all the modules 674 * 675 * Returns 0, or -ENOMEM if memory can't be allocated. 676 */ 677 static int lsm_blob_alloc(void **dest, size_t size, gfp_t gfp) 678 { 679 if (size == 0) { 680 *dest = NULL; 681 return 0; 682 } 683 684 *dest = kzalloc(size, gfp); 685 if (*dest == NULL) 686 return -ENOMEM; 687 return 0; 688 } 689 690 /** 691 * lsm_cred_alloc - allocate a composite cred blob 692 * @cred: the cred that needs a blob 693 * @gfp: allocation type 694 * 695 * Allocate the cred blob for all the modules 696 * 697 * Returns 0, or -ENOMEM if memory can't be allocated. 698 */ 699 static int lsm_cred_alloc(struct cred *cred, gfp_t gfp) 700 { 701 return lsm_blob_alloc(&cred->security, blob_sizes.lbs_cred, gfp); 702 } 703 704 /** 705 * lsm_early_cred - during initialization allocate a composite cred blob 706 * @cred: the cred that needs a blob 707 * 708 * Allocate the cred blob for all the modules 709 */ 710 static void __init lsm_early_cred(struct cred *cred) 711 { 712 int rc = lsm_cred_alloc(cred, GFP_KERNEL); 713 714 if (rc) 715 panic("%s: Early cred alloc failed.\n", __func__); 716 } 717 718 /** 719 * lsm_file_alloc - allocate a composite file blob 720 * @file: the file that needs a blob 721 * 722 * Allocate the file blob for all the modules 723 * 724 * Returns 0, or -ENOMEM if memory can't be allocated. 725 */ 726 static int lsm_file_alloc(struct file *file) 727 { 728 if (!lsm_file_cache) { 729 file->f_security = NULL; 730 return 0; 731 } 732 733 file->f_security = kmem_cache_zalloc(lsm_file_cache, GFP_KERNEL); 734 if (file->f_security == NULL) 735 return -ENOMEM; 736 return 0; 737 } 738 739 /** 740 * lsm_inode_alloc - allocate a composite inode blob 741 * @inode: the inode that needs a blob 742 * @gfp: allocation flags 743 * 744 * Allocate the inode blob for all the modules 745 * 746 * Returns 0, or -ENOMEM if memory can't be allocated. 747 */ 748 static int lsm_inode_alloc(struct inode *inode, gfp_t gfp) 749 { 750 if (!lsm_inode_cache) { 751 inode->i_security = NULL; 752 return 0; 753 } 754 755 inode->i_security = kmem_cache_zalloc(lsm_inode_cache, gfp); 756 if (inode->i_security == NULL) 757 return -ENOMEM; 758 return 0; 759 } 760 761 /** 762 * lsm_task_alloc - allocate a composite task blob 763 * @task: the task that needs a blob 764 * 765 * Allocate the task blob for all the modules 766 * 767 * Returns 0, or -ENOMEM if memory can't be allocated. 768 */ 769 static int lsm_task_alloc(struct task_struct *task) 770 { 771 return lsm_blob_alloc(&task->security, blob_sizes.lbs_task, GFP_KERNEL); 772 } 773 774 /** 775 * lsm_ipc_alloc - allocate a composite ipc blob 776 * @kip: the ipc that needs a blob 777 * 778 * Allocate the ipc blob for all the modules 779 * 780 * Returns 0, or -ENOMEM if memory can't be allocated. 781 */ 782 static int lsm_ipc_alloc(struct kern_ipc_perm *kip) 783 { 784 return lsm_blob_alloc(&kip->security, blob_sizes.lbs_ipc, GFP_KERNEL); 785 } 786 787 #ifdef CONFIG_KEYS 788 /** 789 * lsm_key_alloc - allocate a composite key blob 790 * @key: the key that needs a blob 791 * 792 * Allocate the key blob for all the modules 793 * 794 * Returns 0, or -ENOMEM if memory can't be allocated. 795 */ 796 static int lsm_key_alloc(struct key *key) 797 { 798 return lsm_blob_alloc(&key->security, blob_sizes.lbs_key, GFP_KERNEL); 799 } 800 #endif /* CONFIG_KEYS */ 801 802 /** 803 * lsm_msg_msg_alloc - allocate a composite msg_msg blob 804 * @mp: the msg_msg that needs a blob 805 * 806 * Allocate the ipc blob for all the modules 807 * 808 * Returns 0, or -ENOMEM if memory can't be allocated. 809 */ 810 static int lsm_msg_msg_alloc(struct msg_msg *mp) 811 { 812 return lsm_blob_alloc(&mp->security, blob_sizes.lbs_msg_msg, 813 GFP_KERNEL); 814 } 815 816 /** 817 * lsm_bdev_alloc - allocate a composite block_device blob 818 * @bdev: the block_device that needs a blob 819 * 820 * Allocate the block_device blob for all the modules 821 * 822 * Returns 0, or -ENOMEM if memory can't be allocated. 823 */ 824 static int lsm_bdev_alloc(struct block_device *bdev) 825 { 826 if (blob_sizes.lbs_bdev == 0) { 827 bdev->bd_security = NULL; 828 return 0; 829 } 830 831 bdev->bd_security = kzalloc(blob_sizes.lbs_bdev, GFP_KERNEL); 832 if (!bdev->bd_security) 833 return -ENOMEM; 834 835 return 0; 836 } 837 838 /** 839 * lsm_early_task - during initialization allocate a composite task blob 840 * @task: the task that needs a blob 841 * 842 * Allocate the task blob for all the modules 843 */ 844 static void __init lsm_early_task(struct task_struct *task) 845 { 846 int rc = lsm_task_alloc(task); 847 848 if (rc) 849 panic("%s: Early task alloc failed.\n", __func__); 850 } 851 852 /** 853 * lsm_superblock_alloc - allocate a composite superblock blob 854 * @sb: the superblock that needs a blob 855 * 856 * Allocate the superblock blob for all the modules 857 * 858 * Returns 0, or -ENOMEM if memory can't be allocated. 859 */ 860 static int lsm_superblock_alloc(struct super_block *sb) 861 { 862 return lsm_blob_alloc(&sb->s_security, blob_sizes.lbs_superblock, 863 GFP_KERNEL); 864 } 865 866 /** 867 * lsm_fill_user_ctx - Fill a user space lsm_ctx structure 868 * @uctx: a userspace LSM context to be filled 869 * @uctx_len: available uctx size (input), used uctx size (output) 870 * @val: the new LSM context value 871 * @val_len: the size of the new LSM context value 872 * @id: LSM id 873 * @flags: LSM defined flags 874 * 875 * Fill all of the fields in a userspace lsm_ctx structure. If @uctx is NULL 876 * simply calculate the required size to output via @utc_len and return 877 * success. 878 * 879 * Returns 0 on success, -E2BIG if userspace buffer is not large enough, 880 * -EFAULT on a copyout error, -ENOMEM if memory can't be allocated. 881 */ 882 int lsm_fill_user_ctx(struct lsm_ctx __user *uctx, u32 *uctx_len, 883 void *val, size_t val_len, 884 u64 id, u64 flags) 885 { 886 struct lsm_ctx *nctx = NULL; 887 size_t nctx_len; 888 int rc = 0; 889 890 nctx_len = ALIGN(struct_size(nctx, ctx, val_len), sizeof(void *)); 891 if (nctx_len > *uctx_len) { 892 rc = -E2BIG; 893 goto out; 894 } 895 896 /* no buffer - return success/0 and set @uctx_len to the req size */ 897 if (!uctx) 898 goto out; 899 900 nctx = kzalloc(nctx_len, GFP_KERNEL); 901 if (nctx == NULL) { 902 rc = -ENOMEM; 903 goto out; 904 } 905 nctx->id = id; 906 nctx->flags = flags; 907 nctx->len = nctx_len; 908 nctx->ctx_len = val_len; 909 memcpy(nctx->ctx, val, val_len); 910 911 if (copy_to_user(uctx, nctx, nctx_len)) 912 rc = -EFAULT; 913 914 out: 915 kfree(nctx); 916 *uctx_len = nctx_len; 917 return rc; 918 } 919 920 /* 921 * The default value of the LSM hook is defined in linux/lsm_hook_defs.h and 922 * can be accessed with: 923 * 924 * LSM_RET_DEFAULT(<hook_name>) 925 * 926 * The macros below define static constants for the default value of each 927 * LSM hook. 928 */ 929 #define LSM_RET_DEFAULT(NAME) (NAME##_default) 930 #define DECLARE_LSM_RET_DEFAULT_void(DEFAULT, NAME) 931 #define DECLARE_LSM_RET_DEFAULT_int(DEFAULT, NAME) \ 932 static const int __maybe_unused LSM_RET_DEFAULT(NAME) = (DEFAULT); 933 #define LSM_HOOK(RET, DEFAULT, NAME, ...) \ 934 DECLARE_LSM_RET_DEFAULT_##RET(DEFAULT, NAME) 935 936 #include <linux/lsm_hook_defs.h> 937 #undef LSM_HOOK 938 939 /* 940 * Hook list operation macros. 941 * 942 * call_void_hook: 943 * This is a hook that does not return a value. 944 * 945 * call_int_hook: 946 * This is a hook that returns a value. 947 */ 948 #define __CALL_STATIC_VOID(NUM, HOOK, ...) \ 949 do { \ 950 if (static_branch_unlikely(&SECURITY_HOOK_ACTIVE_KEY(HOOK, NUM))) { \ 951 static_call(LSM_STATIC_CALL(HOOK, NUM))(__VA_ARGS__); \ 952 } \ 953 } while (0); 954 955 #define call_void_hook(HOOK, ...) \ 956 do { \ 957 LSM_LOOP_UNROLL(__CALL_STATIC_VOID, HOOK, __VA_ARGS__); \ 958 } while (0) 959 960 961 #define __CALL_STATIC_INT(NUM, R, HOOK, LABEL, ...) \ 962 do { \ 963 if (static_branch_unlikely(&SECURITY_HOOK_ACTIVE_KEY(HOOK, NUM))) { \ 964 R = static_call(LSM_STATIC_CALL(HOOK, NUM))(__VA_ARGS__); \ 965 if (R != LSM_RET_DEFAULT(HOOK)) \ 966 goto LABEL; \ 967 } \ 968 } while (0); 969 970 #define call_int_hook(HOOK, ...) \ 971 ({ \ 972 __label__ OUT; \ 973 int RC = LSM_RET_DEFAULT(HOOK); \ 974 \ 975 LSM_LOOP_UNROLL(__CALL_STATIC_INT, RC, HOOK, OUT, __VA_ARGS__); \ 976 OUT: \ 977 RC; \ 978 }) 979 980 #define lsm_for_each_hook(scall, NAME) \ 981 for (scall = static_calls_table.NAME; \ 982 scall - static_calls_table.NAME < MAX_LSM_COUNT; scall++) \ 983 if (static_key_enabled(&scall->active->key)) 984 985 /* Security operations */ 986 987 /** 988 * security_binder_set_context_mgr() - Check if becoming binder ctx mgr is ok 989 * @mgr: task credentials of current binder process 990 * 991 * Check whether @mgr is allowed to be the binder context manager. 992 * 993 * Return: Return 0 if permission is granted. 994 */ 995 int security_binder_set_context_mgr(const struct cred *mgr) 996 { 997 return call_int_hook(binder_set_context_mgr, mgr); 998 } 999 1000 /** 1001 * security_binder_transaction() - Check if a binder transaction is allowed 1002 * @from: sending process 1003 * @to: receiving process 1004 * 1005 * Check whether @from is allowed to invoke a binder transaction call to @to. 1006 * 1007 * Return: Returns 0 if permission is granted. 1008 */ 1009 int security_binder_transaction(const struct cred *from, 1010 const struct cred *to) 1011 { 1012 return call_int_hook(binder_transaction, from, to); 1013 } 1014 1015 /** 1016 * security_binder_transfer_binder() - Check if a binder transfer is allowed 1017 * @from: sending process 1018 * @to: receiving process 1019 * 1020 * Check whether @from is allowed to transfer a binder reference to @to. 1021 * 1022 * Return: Returns 0 if permission is granted. 1023 */ 1024 int security_binder_transfer_binder(const struct cred *from, 1025 const struct cred *to) 1026 { 1027 return call_int_hook(binder_transfer_binder, from, to); 1028 } 1029 1030 /** 1031 * security_binder_transfer_file() - Check if a binder file xfer is allowed 1032 * @from: sending process 1033 * @to: receiving process 1034 * @file: file being transferred 1035 * 1036 * Check whether @from is allowed to transfer @file to @to. 1037 * 1038 * Return: Returns 0 if permission is granted. 1039 */ 1040 int security_binder_transfer_file(const struct cred *from, 1041 const struct cred *to, const struct file *file) 1042 { 1043 return call_int_hook(binder_transfer_file, from, to, file); 1044 } 1045 1046 /** 1047 * security_ptrace_access_check() - Check if tracing is allowed 1048 * @child: target process 1049 * @mode: PTRACE_MODE flags 1050 * 1051 * Check permission before allowing the current process to trace the @child 1052 * process. Security modules may also want to perform a process tracing check 1053 * during an execve in the set_security or apply_creds hooks of tracing check 1054 * during an execve in the bprm_set_creds hook of binprm_security_ops if the 1055 * process is being traced and its security attributes would be changed by the 1056 * execve. 1057 * 1058 * Return: Returns 0 if permission is granted. 1059 */ 1060 int security_ptrace_access_check(struct task_struct *child, unsigned int mode) 1061 { 1062 return call_int_hook(ptrace_access_check, child, mode); 1063 } 1064 1065 /** 1066 * security_ptrace_traceme() - Check if tracing is allowed 1067 * @parent: tracing process 1068 * 1069 * Check that the @parent process has sufficient permission to trace the 1070 * current process before allowing the current process to present itself to the 1071 * @parent process for tracing. 1072 * 1073 * Return: Returns 0 if permission is granted. 1074 */ 1075 int security_ptrace_traceme(struct task_struct *parent) 1076 { 1077 return call_int_hook(ptrace_traceme, parent); 1078 } 1079 1080 /** 1081 * security_capget() - Get the capability sets for a process 1082 * @target: target process 1083 * @effective: effective capability set 1084 * @inheritable: inheritable capability set 1085 * @permitted: permitted capability set 1086 * 1087 * Get the @effective, @inheritable, and @permitted capability sets for the 1088 * @target process. The hook may also perform permission checking to determine 1089 * if the current process is allowed to see the capability sets of the @target 1090 * process. 1091 * 1092 * Return: Returns 0 if the capability sets were successfully obtained. 1093 */ 1094 int security_capget(const struct task_struct *target, 1095 kernel_cap_t *effective, 1096 kernel_cap_t *inheritable, 1097 kernel_cap_t *permitted) 1098 { 1099 return call_int_hook(capget, target, effective, inheritable, permitted); 1100 } 1101 1102 /** 1103 * security_capset() - Set the capability sets for a process 1104 * @new: new credentials for the target process 1105 * @old: current credentials of the target process 1106 * @effective: effective capability set 1107 * @inheritable: inheritable capability set 1108 * @permitted: permitted capability set 1109 * 1110 * Set the @effective, @inheritable, and @permitted capability sets for the 1111 * current process. 1112 * 1113 * Return: Returns 0 and update @new if permission is granted. 1114 */ 1115 int security_capset(struct cred *new, const struct cred *old, 1116 const kernel_cap_t *effective, 1117 const kernel_cap_t *inheritable, 1118 const kernel_cap_t *permitted) 1119 { 1120 return call_int_hook(capset, new, old, effective, inheritable, 1121 permitted); 1122 } 1123 1124 /** 1125 * security_capable() - Check if a process has the necessary capability 1126 * @cred: credentials to examine 1127 * @ns: user namespace 1128 * @cap: capability requested 1129 * @opts: capability check options 1130 * 1131 * Check whether the @tsk process has the @cap capability in the indicated 1132 * credentials. @cap contains the capability <include/linux/capability.h>. 1133 * @opts contains options for the capable check <include/linux/security.h>. 1134 * 1135 * Return: Returns 0 if the capability is granted. 1136 */ 1137 int security_capable(const struct cred *cred, 1138 struct user_namespace *ns, 1139 int cap, 1140 unsigned int opts) 1141 { 1142 return call_int_hook(capable, cred, ns, cap, opts); 1143 } 1144 1145 /** 1146 * security_quotactl() - Check if a quotactl() syscall is allowed for this fs 1147 * @cmds: commands 1148 * @type: type 1149 * @id: id 1150 * @sb: filesystem 1151 * 1152 * Check whether the quotactl syscall is allowed for this @sb. 1153 * 1154 * Return: Returns 0 if permission is granted. 1155 */ 1156 int security_quotactl(int cmds, int type, int id, const struct super_block *sb) 1157 { 1158 return call_int_hook(quotactl, cmds, type, id, sb); 1159 } 1160 1161 /** 1162 * security_quota_on() - Check if QUOTAON is allowed for a dentry 1163 * @dentry: dentry 1164 * 1165 * Check whether QUOTAON is allowed for @dentry. 1166 * 1167 * Return: Returns 0 if permission is granted. 1168 */ 1169 int security_quota_on(struct dentry *dentry) 1170 { 1171 return call_int_hook(quota_on, dentry); 1172 } 1173 1174 /** 1175 * security_syslog() - Check if accessing the kernel message ring is allowed 1176 * @type: SYSLOG_ACTION_* type 1177 * 1178 * Check permission before accessing the kernel message ring or changing 1179 * logging to the console. See the syslog(2) manual page for an explanation of 1180 * the @type values. 1181 * 1182 * Return: Return 0 if permission is granted. 1183 */ 1184 int security_syslog(int type) 1185 { 1186 return call_int_hook(syslog, type); 1187 } 1188 1189 /** 1190 * security_settime64() - Check if changing the system time is allowed 1191 * @ts: new time 1192 * @tz: timezone 1193 * 1194 * Check permission to change the system time, struct timespec64 is defined in 1195 * <include/linux/time64.h> and timezone is defined in <include/linux/time.h>. 1196 * 1197 * Return: Returns 0 if permission is granted. 1198 */ 1199 int security_settime64(const struct timespec64 *ts, const struct timezone *tz) 1200 { 1201 return call_int_hook(settime, ts, tz); 1202 } 1203 1204 /** 1205 * security_vm_enough_memory_mm() - Check if allocating a new mem map is allowed 1206 * @mm: mm struct 1207 * @pages: number of pages 1208 * 1209 * Check permissions for allocating a new virtual mapping. If all LSMs return 1210 * a positive value, __vm_enough_memory() will be called with cap_sys_admin 1211 * set. If at least one LSM returns 0 or negative, __vm_enough_memory() will be 1212 * called with cap_sys_admin cleared. 1213 * 1214 * Return: Returns 0 if permission is granted by the LSM infrastructure to the 1215 * caller. 1216 */ 1217 int security_vm_enough_memory_mm(struct mm_struct *mm, long pages) 1218 { 1219 struct lsm_static_call *scall; 1220 int cap_sys_admin = 1; 1221 int rc; 1222 1223 /* 1224 * The module will respond with 0 if it thinks the __vm_enough_memory() 1225 * call should be made with the cap_sys_admin set. If all of the modules 1226 * agree that it should be set it will. If any module thinks it should 1227 * not be set it won't. 1228 */ 1229 lsm_for_each_hook(scall, vm_enough_memory) { 1230 rc = scall->hl->hook.vm_enough_memory(mm, pages); 1231 if (rc < 0) { 1232 cap_sys_admin = 0; 1233 break; 1234 } 1235 } 1236 return __vm_enough_memory(mm, pages, cap_sys_admin); 1237 } 1238 1239 /** 1240 * security_bprm_creds_for_exec() - Prepare the credentials for exec() 1241 * @bprm: binary program information 1242 * 1243 * If the setup in prepare_exec_creds did not setup @bprm->cred->security 1244 * properly for executing @bprm->file, update the LSM's portion of 1245 * @bprm->cred->security to be what commit_creds needs to install for the new 1246 * program. This hook may also optionally check permissions (e.g. for 1247 * transitions between security domains). The hook must set @bprm->secureexec 1248 * to 1 if AT_SECURE should be set to request libc enable secure mode. @bprm 1249 * contains the linux_binprm structure. 1250 * 1251 * If execveat(2) is called with the AT_EXECVE_CHECK flag, bprm->is_check is 1252 * set. The result must be the same as without this flag even if the execution 1253 * will never really happen and @bprm will always be dropped. 1254 * 1255 * This hook must not change current->cred, only @bprm->cred. 1256 * 1257 * Return: Returns 0 if the hook is successful and permission is granted. 1258 */ 1259 int security_bprm_creds_for_exec(struct linux_binprm *bprm) 1260 { 1261 return call_int_hook(bprm_creds_for_exec, bprm); 1262 } 1263 1264 /** 1265 * security_bprm_creds_from_file() - Update linux_binprm creds based on file 1266 * @bprm: binary program information 1267 * @file: associated file 1268 * 1269 * If @file is setpcap, suid, sgid or otherwise marked to change privilege upon 1270 * exec, update @bprm->cred to reflect that change. This is called after 1271 * finding the binary that will be executed without an interpreter. This 1272 * ensures that the credentials will not be derived from a script that the 1273 * binary will need to reopen, which when reopend may end up being a completely 1274 * different file. This hook may also optionally check permissions (e.g. for 1275 * transitions between security domains). The hook must set @bprm->secureexec 1276 * to 1 if AT_SECURE should be set to request libc enable secure mode. The 1277 * hook must add to @bprm->per_clear any personality flags that should be 1278 * cleared from current->personality. @bprm contains the linux_binprm 1279 * structure. 1280 * 1281 * Return: Returns 0 if the hook is successful and permission is granted. 1282 */ 1283 int security_bprm_creds_from_file(struct linux_binprm *bprm, const struct file *file) 1284 { 1285 return call_int_hook(bprm_creds_from_file, bprm, file); 1286 } 1287 1288 /** 1289 * security_bprm_check() - Mediate binary handler search 1290 * @bprm: binary program information 1291 * 1292 * This hook mediates the point when a search for a binary handler will begin. 1293 * It allows a check against the @bprm->cred->security value which was set in 1294 * the preceding creds_for_exec call. The argv list and envp list are reliably 1295 * available in @bprm. This hook may be called multiple times during a single 1296 * execve. @bprm contains the linux_binprm structure. 1297 * 1298 * Return: Returns 0 if the hook is successful and permission is granted. 1299 */ 1300 int security_bprm_check(struct linux_binprm *bprm) 1301 { 1302 return call_int_hook(bprm_check_security, bprm); 1303 } 1304 1305 /** 1306 * security_bprm_committing_creds() - Install creds for a process during exec() 1307 * @bprm: binary program information 1308 * 1309 * Prepare to install the new security attributes of a process being 1310 * transformed by an execve operation, based on the old credentials pointed to 1311 * by @current->cred and the information set in @bprm->cred by the 1312 * bprm_creds_for_exec hook. @bprm points to the linux_binprm structure. This 1313 * hook is a good place to perform state changes on the process such as closing 1314 * open file descriptors to which access will no longer be granted when the 1315 * attributes are changed. This is called immediately before commit_creds(). 1316 */ 1317 void security_bprm_committing_creds(const struct linux_binprm *bprm) 1318 { 1319 call_void_hook(bprm_committing_creds, bprm); 1320 } 1321 1322 /** 1323 * security_bprm_committed_creds() - Tidy up after cred install during exec() 1324 * @bprm: binary program information 1325 * 1326 * Tidy up after the installation of the new security attributes of a process 1327 * being transformed by an execve operation. The new credentials have, by this 1328 * point, been set to @current->cred. @bprm points to the linux_binprm 1329 * structure. This hook is a good place to perform state changes on the 1330 * process such as clearing out non-inheritable signal state. This is called 1331 * immediately after commit_creds(). 1332 */ 1333 void security_bprm_committed_creds(const struct linux_binprm *bprm) 1334 { 1335 call_void_hook(bprm_committed_creds, bprm); 1336 } 1337 1338 /** 1339 * security_fs_context_submount() - Initialise fc->security 1340 * @fc: new filesystem context 1341 * @reference: dentry reference for submount/remount 1342 * 1343 * Fill out the ->security field for a new fs_context. 1344 * 1345 * Return: Returns 0 on success or negative error code on failure. 1346 */ 1347 int security_fs_context_submount(struct fs_context *fc, struct super_block *reference) 1348 { 1349 return call_int_hook(fs_context_submount, fc, reference); 1350 } 1351 1352 /** 1353 * security_fs_context_dup() - Duplicate a fs_context LSM blob 1354 * @fc: destination filesystem context 1355 * @src_fc: source filesystem context 1356 * 1357 * Allocate and attach a security structure to sc->security. This pointer is 1358 * initialised to NULL by the caller. @fc indicates the new filesystem context. 1359 * @src_fc indicates the original filesystem context. 1360 * 1361 * Return: Returns 0 on success or a negative error code on failure. 1362 */ 1363 int security_fs_context_dup(struct fs_context *fc, struct fs_context *src_fc) 1364 { 1365 return call_int_hook(fs_context_dup, fc, src_fc); 1366 } 1367 1368 /** 1369 * security_fs_context_parse_param() - Configure a filesystem context 1370 * @fc: filesystem context 1371 * @param: filesystem parameter 1372 * 1373 * Userspace provided a parameter to configure a superblock. The LSM can 1374 * consume the parameter or return it to the caller for use elsewhere. 1375 * 1376 * Return: If the parameter is used by the LSM it should return 0, if it is 1377 * returned to the caller -ENOPARAM is returned, otherwise a negative 1378 * error code is returned. 1379 */ 1380 int security_fs_context_parse_param(struct fs_context *fc, 1381 struct fs_parameter *param) 1382 { 1383 struct lsm_static_call *scall; 1384 int trc; 1385 int rc = -ENOPARAM; 1386 1387 lsm_for_each_hook(scall, fs_context_parse_param) { 1388 trc = scall->hl->hook.fs_context_parse_param(fc, param); 1389 if (trc == 0) 1390 rc = 0; 1391 else if (trc != -ENOPARAM) 1392 return trc; 1393 } 1394 return rc; 1395 } 1396 1397 /** 1398 * security_sb_alloc() - Allocate a super_block LSM blob 1399 * @sb: filesystem superblock 1400 * 1401 * Allocate and attach a security structure to the sb->s_security field. The 1402 * s_security field is initialized to NULL when the structure is allocated. 1403 * @sb contains the super_block structure to be modified. 1404 * 1405 * Return: Returns 0 if operation was successful. 1406 */ 1407 int security_sb_alloc(struct super_block *sb) 1408 { 1409 int rc = lsm_superblock_alloc(sb); 1410 1411 if (unlikely(rc)) 1412 return rc; 1413 rc = call_int_hook(sb_alloc_security, sb); 1414 if (unlikely(rc)) 1415 security_sb_free(sb); 1416 return rc; 1417 } 1418 1419 /** 1420 * security_sb_delete() - Release super_block LSM associated objects 1421 * @sb: filesystem superblock 1422 * 1423 * Release objects tied to a superblock (e.g. inodes). @sb contains the 1424 * super_block structure being released. 1425 */ 1426 void security_sb_delete(struct super_block *sb) 1427 { 1428 call_void_hook(sb_delete, sb); 1429 } 1430 1431 /** 1432 * security_sb_free() - Free a super_block LSM blob 1433 * @sb: filesystem superblock 1434 * 1435 * Deallocate and clear the sb->s_security field. @sb contains the super_block 1436 * structure to be modified. 1437 */ 1438 void security_sb_free(struct super_block *sb) 1439 { 1440 call_void_hook(sb_free_security, sb); 1441 kfree(sb->s_security); 1442 sb->s_security = NULL; 1443 } 1444 1445 /** 1446 * security_free_mnt_opts() - Free memory associated with mount options 1447 * @mnt_opts: LSM processed mount options 1448 * 1449 * Free memory associated with @mnt_ops. 1450 */ 1451 void security_free_mnt_opts(void **mnt_opts) 1452 { 1453 if (!*mnt_opts) 1454 return; 1455 call_void_hook(sb_free_mnt_opts, *mnt_opts); 1456 *mnt_opts = NULL; 1457 } 1458 EXPORT_SYMBOL(security_free_mnt_opts); 1459 1460 /** 1461 * security_sb_eat_lsm_opts() - Consume LSM mount options 1462 * @options: mount options 1463 * @mnt_opts: LSM processed mount options 1464 * 1465 * Eat (scan @options) and save them in @mnt_opts. 1466 * 1467 * Return: Returns 0 on success, negative values on failure. 1468 */ 1469 int security_sb_eat_lsm_opts(char *options, void **mnt_opts) 1470 { 1471 return call_int_hook(sb_eat_lsm_opts, options, mnt_opts); 1472 } 1473 EXPORT_SYMBOL(security_sb_eat_lsm_opts); 1474 1475 /** 1476 * security_sb_mnt_opts_compat() - Check if new mount options are allowed 1477 * @sb: filesystem superblock 1478 * @mnt_opts: new mount options 1479 * 1480 * Determine if the new mount options in @mnt_opts are allowed given the 1481 * existing mounted filesystem at @sb. @sb superblock being compared. 1482 * 1483 * Return: Returns 0 if options are compatible. 1484 */ 1485 int security_sb_mnt_opts_compat(struct super_block *sb, 1486 void *mnt_opts) 1487 { 1488 return call_int_hook(sb_mnt_opts_compat, sb, mnt_opts); 1489 } 1490 EXPORT_SYMBOL(security_sb_mnt_opts_compat); 1491 1492 /** 1493 * security_sb_remount() - Verify no incompatible mount changes during remount 1494 * @sb: filesystem superblock 1495 * @mnt_opts: (re)mount options 1496 * 1497 * Extracts security system specific mount options and verifies no changes are 1498 * being made to those options. 1499 * 1500 * Return: Returns 0 if permission is granted. 1501 */ 1502 int security_sb_remount(struct super_block *sb, 1503 void *mnt_opts) 1504 { 1505 return call_int_hook(sb_remount, sb, mnt_opts); 1506 } 1507 EXPORT_SYMBOL(security_sb_remount); 1508 1509 /** 1510 * security_sb_kern_mount() - Check if a kernel mount is allowed 1511 * @sb: filesystem superblock 1512 * 1513 * Mount this @sb if allowed by permissions. 1514 * 1515 * Return: Returns 0 if permission is granted. 1516 */ 1517 int security_sb_kern_mount(const struct super_block *sb) 1518 { 1519 return call_int_hook(sb_kern_mount, sb); 1520 } 1521 1522 /** 1523 * security_sb_show_options() - Output the mount options for a superblock 1524 * @m: output file 1525 * @sb: filesystem superblock 1526 * 1527 * Show (print on @m) mount options for this @sb. 1528 * 1529 * Return: Returns 0 on success, negative values on failure. 1530 */ 1531 int security_sb_show_options(struct seq_file *m, struct super_block *sb) 1532 { 1533 return call_int_hook(sb_show_options, m, sb); 1534 } 1535 1536 /** 1537 * security_sb_statfs() - Check if accessing fs stats is allowed 1538 * @dentry: superblock handle 1539 * 1540 * Check permission before obtaining filesystem statistics for the @mnt 1541 * mountpoint. @dentry is a handle on the superblock for the filesystem. 1542 * 1543 * Return: Returns 0 if permission is granted. 1544 */ 1545 int security_sb_statfs(struct dentry *dentry) 1546 { 1547 return call_int_hook(sb_statfs, dentry); 1548 } 1549 1550 /** 1551 * security_sb_mount() - Check permission for mounting a filesystem 1552 * @dev_name: filesystem backing device 1553 * @path: mount point 1554 * @type: filesystem type 1555 * @flags: mount flags 1556 * @data: filesystem specific data 1557 * 1558 * Check permission before an object specified by @dev_name is mounted on the 1559 * mount point named by @nd. For an ordinary mount, @dev_name identifies a 1560 * device if the file system type requires a device. For a remount 1561 * (@flags & MS_REMOUNT), @dev_name is irrelevant. For a loopback/bind mount 1562 * (@flags & MS_BIND), @dev_name identifies the pathname of the object being 1563 * mounted. 1564 * 1565 * Return: Returns 0 if permission is granted. 1566 */ 1567 int security_sb_mount(const char *dev_name, const struct path *path, 1568 const char *type, unsigned long flags, void *data) 1569 { 1570 return call_int_hook(sb_mount, dev_name, path, type, flags, data); 1571 } 1572 1573 /** 1574 * security_sb_umount() - Check permission for unmounting a filesystem 1575 * @mnt: mounted filesystem 1576 * @flags: unmount flags 1577 * 1578 * Check permission before the @mnt file system is unmounted. 1579 * 1580 * Return: Returns 0 if permission is granted. 1581 */ 1582 int security_sb_umount(struct vfsmount *mnt, int flags) 1583 { 1584 return call_int_hook(sb_umount, mnt, flags); 1585 } 1586 1587 /** 1588 * security_sb_pivotroot() - Check permissions for pivoting the rootfs 1589 * @old_path: new location for current rootfs 1590 * @new_path: location of the new rootfs 1591 * 1592 * Check permission before pivoting the root filesystem. 1593 * 1594 * Return: Returns 0 if permission is granted. 1595 */ 1596 int security_sb_pivotroot(const struct path *old_path, 1597 const struct path *new_path) 1598 { 1599 return call_int_hook(sb_pivotroot, old_path, new_path); 1600 } 1601 1602 /** 1603 * security_sb_set_mnt_opts() - Set the mount options for a filesystem 1604 * @sb: filesystem superblock 1605 * @mnt_opts: binary mount options 1606 * @kern_flags: kernel flags (in) 1607 * @set_kern_flags: kernel flags (out) 1608 * 1609 * Set the security relevant mount options used for a superblock. 1610 * 1611 * Return: Returns 0 on success, error on failure. 1612 */ 1613 int security_sb_set_mnt_opts(struct super_block *sb, 1614 void *mnt_opts, 1615 unsigned long kern_flags, 1616 unsigned long *set_kern_flags) 1617 { 1618 struct lsm_static_call *scall; 1619 int rc = mnt_opts ? -EOPNOTSUPP : LSM_RET_DEFAULT(sb_set_mnt_opts); 1620 1621 lsm_for_each_hook(scall, sb_set_mnt_opts) { 1622 rc = scall->hl->hook.sb_set_mnt_opts(sb, mnt_opts, kern_flags, 1623 set_kern_flags); 1624 if (rc != LSM_RET_DEFAULT(sb_set_mnt_opts)) 1625 break; 1626 } 1627 return rc; 1628 } 1629 EXPORT_SYMBOL(security_sb_set_mnt_opts); 1630 1631 /** 1632 * security_sb_clone_mnt_opts() - Duplicate superblock mount options 1633 * @oldsb: source superblock 1634 * @newsb: destination superblock 1635 * @kern_flags: kernel flags (in) 1636 * @set_kern_flags: kernel flags (out) 1637 * 1638 * Copy all security options from a given superblock to another. 1639 * 1640 * Return: Returns 0 on success, error on failure. 1641 */ 1642 int security_sb_clone_mnt_opts(const struct super_block *oldsb, 1643 struct super_block *newsb, 1644 unsigned long kern_flags, 1645 unsigned long *set_kern_flags) 1646 { 1647 return call_int_hook(sb_clone_mnt_opts, oldsb, newsb, 1648 kern_flags, set_kern_flags); 1649 } 1650 EXPORT_SYMBOL(security_sb_clone_mnt_opts); 1651 1652 /** 1653 * security_move_mount() - Check permissions for moving a mount 1654 * @from_path: source mount point 1655 * @to_path: destination mount point 1656 * 1657 * Check permission before a mount is moved. 1658 * 1659 * Return: Returns 0 if permission is granted. 1660 */ 1661 int security_move_mount(const struct path *from_path, 1662 const struct path *to_path) 1663 { 1664 return call_int_hook(move_mount, from_path, to_path); 1665 } 1666 1667 /** 1668 * security_path_notify() - Check if setting a watch is allowed 1669 * @path: file path 1670 * @mask: event mask 1671 * @obj_type: file path type 1672 * 1673 * Check permissions before setting a watch on events as defined by @mask, on 1674 * an object at @path, whose type is defined by @obj_type. 1675 * 1676 * Return: Returns 0 if permission is granted. 1677 */ 1678 int security_path_notify(const struct path *path, u64 mask, 1679 unsigned int obj_type) 1680 { 1681 return call_int_hook(path_notify, path, mask, obj_type); 1682 } 1683 1684 /** 1685 * security_inode_alloc() - Allocate an inode LSM blob 1686 * @inode: the inode 1687 * @gfp: allocation flags 1688 * 1689 * Allocate and attach a security structure to @inode->i_security. The 1690 * i_security field is initialized to NULL when the inode structure is 1691 * allocated. 1692 * 1693 * Return: Return 0 if operation was successful. 1694 */ 1695 int security_inode_alloc(struct inode *inode, gfp_t gfp) 1696 { 1697 int rc = lsm_inode_alloc(inode, gfp); 1698 1699 if (unlikely(rc)) 1700 return rc; 1701 rc = call_int_hook(inode_alloc_security, inode); 1702 if (unlikely(rc)) 1703 security_inode_free(inode); 1704 return rc; 1705 } 1706 1707 static void inode_free_by_rcu(struct rcu_head *head) 1708 { 1709 /* The rcu head is at the start of the inode blob */ 1710 call_void_hook(inode_free_security_rcu, head); 1711 kmem_cache_free(lsm_inode_cache, head); 1712 } 1713 1714 /** 1715 * security_inode_free() - Free an inode's LSM blob 1716 * @inode: the inode 1717 * 1718 * Release any LSM resources associated with @inode, although due to the 1719 * inode's RCU protections it is possible that the resources will not be 1720 * fully released until after the current RCU grace period has elapsed. 1721 * 1722 * It is important for LSMs to note that despite being present in a call to 1723 * security_inode_free(), @inode may still be referenced in a VFS path walk 1724 * and calls to security_inode_permission() may be made during, or after, 1725 * a call to security_inode_free(). For this reason the inode->i_security 1726 * field is released via a call_rcu() callback and any LSMs which need to 1727 * retain inode state for use in security_inode_permission() should only 1728 * release that state in the inode_free_security_rcu() LSM hook callback. 1729 */ 1730 void security_inode_free(struct inode *inode) 1731 { 1732 call_void_hook(inode_free_security, inode); 1733 if (!inode->i_security) 1734 return; 1735 call_rcu((struct rcu_head *)inode->i_security, inode_free_by_rcu); 1736 } 1737 1738 /** 1739 * security_dentry_init_security() - Perform dentry initialization 1740 * @dentry: the dentry to initialize 1741 * @mode: mode used to determine resource type 1742 * @name: name of the last path component 1743 * @xattr_name: name of the security/LSM xattr 1744 * @lsmctx: pointer to the resulting LSM context 1745 * 1746 * Compute a context for a dentry as the inode is not yet available since NFSv4 1747 * has no label backed by an EA anyway. It is important to note that 1748 * @xattr_name does not need to be free'd by the caller, it is a static string. 1749 * 1750 * Return: Returns 0 on success, negative values on failure. 1751 */ 1752 int security_dentry_init_security(struct dentry *dentry, int mode, 1753 const struct qstr *name, 1754 const char **xattr_name, 1755 struct lsm_context *lsmctx) 1756 { 1757 return call_int_hook(dentry_init_security, dentry, mode, name, 1758 xattr_name, lsmctx); 1759 } 1760 EXPORT_SYMBOL(security_dentry_init_security); 1761 1762 /** 1763 * security_dentry_create_files_as() - Perform dentry initialization 1764 * @dentry: the dentry to initialize 1765 * @mode: mode used to determine resource type 1766 * @name: name of the last path component 1767 * @old: creds to use for LSM context calculations 1768 * @new: creds to modify 1769 * 1770 * Compute a context for a dentry as the inode is not yet available and set 1771 * that context in passed in creds so that new files are created using that 1772 * context. Context is calculated using the passed in creds and not the creds 1773 * of the caller. 1774 * 1775 * Return: Returns 0 on success, error on failure. 1776 */ 1777 int security_dentry_create_files_as(struct dentry *dentry, int mode, 1778 struct qstr *name, 1779 const struct cred *old, struct cred *new) 1780 { 1781 return call_int_hook(dentry_create_files_as, dentry, mode, 1782 name, old, new); 1783 } 1784 EXPORT_SYMBOL(security_dentry_create_files_as); 1785 1786 /** 1787 * security_inode_init_security() - Initialize an inode's LSM context 1788 * @inode: the inode 1789 * @dir: parent directory 1790 * @qstr: last component of the pathname 1791 * @initxattrs: callback function to write xattrs 1792 * @fs_data: filesystem specific data 1793 * 1794 * Obtain the security attribute name suffix and value to set on a newly 1795 * created inode and set up the incore security field for the new inode. This 1796 * hook is called by the fs code as part of the inode creation transaction and 1797 * provides for atomic labeling of the inode, unlike the post_create/mkdir/... 1798 * hooks called by the VFS. 1799 * 1800 * The hook function is expected to populate the xattrs array, by calling 1801 * lsm_get_xattr_slot() to retrieve the slots reserved by the security module 1802 * with the lbs_xattr_count field of the lsm_blob_sizes structure. For each 1803 * slot, the hook function should set ->name to the attribute name suffix 1804 * (e.g. selinux), to allocate ->value (will be freed by the caller) and set it 1805 * to the attribute value, to set ->value_len to the length of the value. If 1806 * the security module does not use security attributes or does not wish to put 1807 * a security attribute on this particular inode, then it should return 1808 * -EOPNOTSUPP to skip this processing. 1809 * 1810 * Return: Returns 0 if the LSM successfully initialized all of the inode 1811 * security attributes that are required, negative values otherwise. 1812 */ 1813 int security_inode_init_security(struct inode *inode, struct inode *dir, 1814 const struct qstr *qstr, 1815 const initxattrs initxattrs, void *fs_data) 1816 { 1817 struct lsm_static_call *scall; 1818 struct xattr *new_xattrs = NULL; 1819 int ret = -EOPNOTSUPP, xattr_count = 0; 1820 1821 if (unlikely(IS_PRIVATE(inode))) 1822 return 0; 1823 1824 if (!blob_sizes.lbs_xattr_count) 1825 return 0; 1826 1827 if (initxattrs) { 1828 /* Allocate +1 as terminator. */ 1829 new_xattrs = kcalloc(blob_sizes.lbs_xattr_count + 1, 1830 sizeof(*new_xattrs), GFP_NOFS); 1831 if (!new_xattrs) 1832 return -ENOMEM; 1833 } 1834 1835 lsm_for_each_hook(scall, inode_init_security) { 1836 ret = scall->hl->hook.inode_init_security(inode, dir, qstr, new_xattrs, 1837 &xattr_count); 1838 if (ret && ret != -EOPNOTSUPP) 1839 goto out; 1840 /* 1841 * As documented in lsm_hooks.h, -EOPNOTSUPP in this context 1842 * means that the LSM is not willing to provide an xattr, not 1843 * that it wants to signal an error. Thus, continue to invoke 1844 * the remaining LSMs. 1845 */ 1846 } 1847 1848 /* If initxattrs() is NULL, xattr_count is zero, skip the call. */ 1849 if (!xattr_count) 1850 goto out; 1851 1852 ret = initxattrs(inode, new_xattrs, fs_data); 1853 out: 1854 for (; xattr_count > 0; xattr_count--) 1855 kfree(new_xattrs[xattr_count - 1].value); 1856 kfree(new_xattrs); 1857 return (ret == -EOPNOTSUPP) ? 0 : ret; 1858 } 1859 EXPORT_SYMBOL(security_inode_init_security); 1860 1861 /** 1862 * security_inode_init_security_anon() - Initialize an anonymous inode 1863 * @inode: the inode 1864 * @name: the anonymous inode class 1865 * @context_inode: an optional related inode 1866 * 1867 * Set up the incore security field for the new anonymous inode and return 1868 * whether the inode creation is permitted by the security module or not. 1869 * 1870 * Return: Returns 0 on success, -EACCES if the security module denies the 1871 * creation of this inode, or another -errno upon other errors. 1872 */ 1873 int security_inode_init_security_anon(struct inode *inode, 1874 const struct qstr *name, 1875 const struct inode *context_inode) 1876 { 1877 return call_int_hook(inode_init_security_anon, inode, name, 1878 context_inode); 1879 } 1880 1881 #ifdef CONFIG_SECURITY_PATH 1882 /** 1883 * security_path_mknod() - Check if creating a special file is allowed 1884 * @dir: parent directory 1885 * @dentry: new file 1886 * @mode: new file mode 1887 * @dev: device number 1888 * 1889 * Check permissions when creating a file. Note that this hook is called even 1890 * if mknod operation is being done for a regular file. 1891 * 1892 * Return: Returns 0 if permission is granted. 1893 */ 1894 int security_path_mknod(const struct path *dir, struct dentry *dentry, 1895 umode_t mode, unsigned int dev) 1896 { 1897 if (unlikely(IS_PRIVATE(d_backing_inode(dir->dentry)))) 1898 return 0; 1899 return call_int_hook(path_mknod, dir, dentry, mode, dev); 1900 } 1901 EXPORT_SYMBOL(security_path_mknod); 1902 1903 /** 1904 * security_path_post_mknod() - Update inode security after reg file creation 1905 * @idmap: idmap of the mount 1906 * @dentry: new file 1907 * 1908 * Update inode security field after a regular file has been created. 1909 */ 1910 void security_path_post_mknod(struct mnt_idmap *idmap, struct dentry *dentry) 1911 { 1912 if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) 1913 return; 1914 call_void_hook(path_post_mknod, idmap, dentry); 1915 } 1916 1917 /** 1918 * security_path_mkdir() - Check if creating a new directory is allowed 1919 * @dir: parent directory 1920 * @dentry: new directory 1921 * @mode: new directory mode 1922 * 1923 * Check permissions to create a new directory in the existing directory. 1924 * 1925 * Return: Returns 0 if permission is granted. 1926 */ 1927 int security_path_mkdir(const struct path *dir, struct dentry *dentry, 1928 umode_t mode) 1929 { 1930 if (unlikely(IS_PRIVATE(d_backing_inode(dir->dentry)))) 1931 return 0; 1932 return call_int_hook(path_mkdir, dir, dentry, mode); 1933 } 1934 EXPORT_SYMBOL(security_path_mkdir); 1935 1936 /** 1937 * security_path_rmdir() - Check if removing a directory is allowed 1938 * @dir: parent directory 1939 * @dentry: directory to remove 1940 * 1941 * Check the permission to remove a directory. 1942 * 1943 * Return: Returns 0 if permission is granted. 1944 */ 1945 int security_path_rmdir(const struct path *dir, struct dentry *dentry) 1946 { 1947 if (unlikely(IS_PRIVATE(d_backing_inode(dir->dentry)))) 1948 return 0; 1949 return call_int_hook(path_rmdir, dir, dentry); 1950 } 1951 1952 /** 1953 * security_path_unlink() - Check if removing a hard link is allowed 1954 * @dir: parent directory 1955 * @dentry: file 1956 * 1957 * Check the permission to remove a hard link to a file. 1958 * 1959 * Return: Returns 0 if permission is granted. 1960 */ 1961 int security_path_unlink(const struct path *dir, struct dentry *dentry) 1962 { 1963 if (unlikely(IS_PRIVATE(d_backing_inode(dir->dentry)))) 1964 return 0; 1965 return call_int_hook(path_unlink, dir, dentry); 1966 } 1967 EXPORT_SYMBOL(security_path_unlink); 1968 1969 /** 1970 * security_path_symlink() - Check if creating a symbolic link is allowed 1971 * @dir: parent directory 1972 * @dentry: symbolic link 1973 * @old_name: file pathname 1974 * 1975 * Check the permission to create a symbolic link to a file. 1976 * 1977 * Return: Returns 0 if permission is granted. 1978 */ 1979 int security_path_symlink(const struct path *dir, struct dentry *dentry, 1980 const char *old_name) 1981 { 1982 if (unlikely(IS_PRIVATE(d_backing_inode(dir->dentry)))) 1983 return 0; 1984 return call_int_hook(path_symlink, dir, dentry, old_name); 1985 } 1986 1987 /** 1988 * security_path_link - Check if creating a hard link is allowed 1989 * @old_dentry: existing file 1990 * @new_dir: new parent directory 1991 * @new_dentry: new link 1992 * 1993 * Check permission before creating a new hard link to a file. 1994 * 1995 * Return: Returns 0 if permission is granted. 1996 */ 1997 int security_path_link(struct dentry *old_dentry, const struct path *new_dir, 1998 struct dentry *new_dentry) 1999 { 2000 if (unlikely(IS_PRIVATE(d_backing_inode(old_dentry)))) 2001 return 0; 2002 return call_int_hook(path_link, old_dentry, new_dir, new_dentry); 2003 } 2004 2005 /** 2006 * security_path_rename() - Check if renaming a file is allowed 2007 * @old_dir: parent directory of the old file 2008 * @old_dentry: the old file 2009 * @new_dir: parent directory of the new file 2010 * @new_dentry: the new file 2011 * @flags: flags 2012 * 2013 * Check for permission to rename a file or directory. 2014 * 2015 * Return: Returns 0 if permission is granted. 2016 */ 2017 int security_path_rename(const struct path *old_dir, struct dentry *old_dentry, 2018 const struct path *new_dir, struct dentry *new_dentry, 2019 unsigned int flags) 2020 { 2021 if (unlikely(IS_PRIVATE(d_backing_inode(old_dentry)) || 2022 (d_is_positive(new_dentry) && 2023 IS_PRIVATE(d_backing_inode(new_dentry))))) 2024 return 0; 2025 2026 return call_int_hook(path_rename, old_dir, old_dentry, new_dir, 2027 new_dentry, flags); 2028 } 2029 EXPORT_SYMBOL(security_path_rename); 2030 2031 /** 2032 * security_path_truncate() - Check if truncating a file is allowed 2033 * @path: file 2034 * 2035 * Check permission before truncating the file indicated by path. Note that 2036 * truncation permissions may also be checked based on already opened files, 2037 * using the security_file_truncate() hook. 2038 * 2039 * Return: Returns 0 if permission is granted. 2040 */ 2041 int security_path_truncate(const struct path *path) 2042 { 2043 if (unlikely(IS_PRIVATE(d_backing_inode(path->dentry)))) 2044 return 0; 2045 return call_int_hook(path_truncate, path); 2046 } 2047 2048 /** 2049 * security_path_chmod() - Check if changing the file's mode is allowed 2050 * @path: file 2051 * @mode: new mode 2052 * 2053 * Check for permission to change a mode of the file @path. The new mode is 2054 * specified in @mode which is a bitmask of constants from 2055 * <include/uapi/linux/stat.h>. 2056 * 2057 * Return: Returns 0 if permission is granted. 2058 */ 2059 int security_path_chmod(const struct path *path, umode_t mode) 2060 { 2061 if (unlikely(IS_PRIVATE(d_backing_inode(path->dentry)))) 2062 return 0; 2063 return call_int_hook(path_chmod, path, mode); 2064 } 2065 2066 /** 2067 * security_path_chown() - Check if changing the file's owner/group is allowed 2068 * @path: file 2069 * @uid: file owner 2070 * @gid: file group 2071 * 2072 * Check for permission to change owner/group of a file or directory. 2073 * 2074 * Return: Returns 0 if permission is granted. 2075 */ 2076 int security_path_chown(const struct path *path, kuid_t uid, kgid_t gid) 2077 { 2078 if (unlikely(IS_PRIVATE(d_backing_inode(path->dentry)))) 2079 return 0; 2080 return call_int_hook(path_chown, path, uid, gid); 2081 } 2082 2083 /** 2084 * security_path_chroot() - Check if changing the root directory is allowed 2085 * @path: directory 2086 * 2087 * Check for permission to change root directory. 2088 * 2089 * Return: Returns 0 if permission is granted. 2090 */ 2091 int security_path_chroot(const struct path *path) 2092 { 2093 return call_int_hook(path_chroot, path); 2094 } 2095 #endif /* CONFIG_SECURITY_PATH */ 2096 2097 /** 2098 * security_inode_create() - Check if creating a file is allowed 2099 * @dir: the parent directory 2100 * @dentry: the file being created 2101 * @mode: requested file mode 2102 * 2103 * Check permission to create a regular file. 2104 * 2105 * Return: Returns 0 if permission is granted. 2106 */ 2107 int security_inode_create(struct inode *dir, struct dentry *dentry, 2108 umode_t mode) 2109 { 2110 if (unlikely(IS_PRIVATE(dir))) 2111 return 0; 2112 return call_int_hook(inode_create, dir, dentry, mode); 2113 } 2114 EXPORT_SYMBOL_GPL(security_inode_create); 2115 2116 /** 2117 * security_inode_post_create_tmpfile() - Update inode security of new tmpfile 2118 * @idmap: idmap of the mount 2119 * @inode: inode of the new tmpfile 2120 * 2121 * Update inode security data after a tmpfile has been created. 2122 */ 2123 void security_inode_post_create_tmpfile(struct mnt_idmap *idmap, 2124 struct inode *inode) 2125 { 2126 if (unlikely(IS_PRIVATE(inode))) 2127 return; 2128 call_void_hook(inode_post_create_tmpfile, idmap, inode); 2129 } 2130 2131 /** 2132 * security_inode_link() - Check if creating a hard link is allowed 2133 * @old_dentry: existing file 2134 * @dir: new parent directory 2135 * @new_dentry: new link 2136 * 2137 * Check permission before creating a new hard link to a file. 2138 * 2139 * Return: Returns 0 if permission is granted. 2140 */ 2141 int security_inode_link(struct dentry *old_dentry, struct inode *dir, 2142 struct dentry *new_dentry) 2143 { 2144 if (unlikely(IS_PRIVATE(d_backing_inode(old_dentry)))) 2145 return 0; 2146 return call_int_hook(inode_link, old_dentry, dir, new_dentry); 2147 } 2148 2149 /** 2150 * security_inode_unlink() - Check if removing a hard link is allowed 2151 * @dir: parent directory 2152 * @dentry: file 2153 * 2154 * Check the permission to remove a hard link to a file. 2155 * 2156 * Return: Returns 0 if permission is granted. 2157 */ 2158 int security_inode_unlink(struct inode *dir, struct dentry *dentry) 2159 { 2160 if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) 2161 return 0; 2162 return call_int_hook(inode_unlink, dir, dentry); 2163 } 2164 2165 /** 2166 * security_inode_symlink() - Check if creating a symbolic link is allowed 2167 * @dir: parent directory 2168 * @dentry: symbolic link 2169 * @old_name: existing filename 2170 * 2171 * Check the permission to create a symbolic link to a file. 2172 * 2173 * Return: Returns 0 if permission is granted. 2174 */ 2175 int security_inode_symlink(struct inode *dir, struct dentry *dentry, 2176 const char *old_name) 2177 { 2178 if (unlikely(IS_PRIVATE(dir))) 2179 return 0; 2180 return call_int_hook(inode_symlink, dir, dentry, old_name); 2181 } 2182 2183 /** 2184 * security_inode_mkdir() - Check if creation a new director is allowed 2185 * @dir: parent directory 2186 * @dentry: new directory 2187 * @mode: new directory mode 2188 * 2189 * Check permissions to create a new directory in the existing directory 2190 * associated with inode structure @dir. 2191 * 2192 * Return: Returns 0 if permission is granted. 2193 */ 2194 int security_inode_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode) 2195 { 2196 if (unlikely(IS_PRIVATE(dir))) 2197 return 0; 2198 return call_int_hook(inode_mkdir, dir, dentry, mode); 2199 } 2200 EXPORT_SYMBOL_GPL(security_inode_mkdir); 2201 2202 /** 2203 * security_inode_rmdir() - Check if removing a directory is allowed 2204 * @dir: parent directory 2205 * @dentry: directory to be removed 2206 * 2207 * Check the permission to remove a directory. 2208 * 2209 * Return: Returns 0 if permission is granted. 2210 */ 2211 int security_inode_rmdir(struct inode *dir, struct dentry *dentry) 2212 { 2213 if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) 2214 return 0; 2215 return call_int_hook(inode_rmdir, dir, dentry); 2216 } 2217 2218 /** 2219 * security_inode_mknod() - Check if creating a special file is allowed 2220 * @dir: parent directory 2221 * @dentry: new file 2222 * @mode: new file mode 2223 * @dev: device number 2224 * 2225 * Check permissions when creating a special file (or a socket or a fifo file 2226 * created via the mknod system call). Note that if mknod operation is being 2227 * done for a regular file, then the create hook will be called and not this 2228 * hook. 2229 * 2230 * Return: Returns 0 if permission is granted. 2231 */ 2232 int security_inode_mknod(struct inode *dir, struct dentry *dentry, 2233 umode_t mode, dev_t dev) 2234 { 2235 if (unlikely(IS_PRIVATE(dir))) 2236 return 0; 2237 return call_int_hook(inode_mknod, dir, dentry, mode, dev); 2238 } 2239 2240 /** 2241 * security_inode_rename() - Check if renaming a file is allowed 2242 * @old_dir: parent directory of the old file 2243 * @old_dentry: the old file 2244 * @new_dir: parent directory of the new file 2245 * @new_dentry: the new file 2246 * @flags: flags 2247 * 2248 * Check for permission to rename a file or directory. 2249 * 2250 * Return: Returns 0 if permission is granted. 2251 */ 2252 int security_inode_rename(struct inode *old_dir, struct dentry *old_dentry, 2253 struct inode *new_dir, struct dentry *new_dentry, 2254 unsigned int flags) 2255 { 2256 if (unlikely(IS_PRIVATE(d_backing_inode(old_dentry)) || 2257 (d_is_positive(new_dentry) && 2258 IS_PRIVATE(d_backing_inode(new_dentry))))) 2259 return 0; 2260 2261 if (flags & RENAME_EXCHANGE) { 2262 int err = call_int_hook(inode_rename, new_dir, new_dentry, 2263 old_dir, old_dentry); 2264 if (err) 2265 return err; 2266 } 2267 2268 return call_int_hook(inode_rename, old_dir, old_dentry, 2269 new_dir, new_dentry); 2270 } 2271 2272 /** 2273 * security_inode_readlink() - Check if reading a symbolic link is allowed 2274 * @dentry: link 2275 * 2276 * Check the permission to read the symbolic link. 2277 * 2278 * Return: Returns 0 if permission is granted. 2279 */ 2280 int security_inode_readlink(struct dentry *dentry) 2281 { 2282 if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) 2283 return 0; 2284 return call_int_hook(inode_readlink, dentry); 2285 } 2286 2287 /** 2288 * security_inode_follow_link() - Check if following a symbolic link is allowed 2289 * @dentry: link dentry 2290 * @inode: link inode 2291 * @rcu: true if in RCU-walk mode 2292 * 2293 * Check permission to follow a symbolic link when looking up a pathname. If 2294 * @rcu is true, @inode is not stable. 2295 * 2296 * Return: Returns 0 if permission is granted. 2297 */ 2298 int security_inode_follow_link(struct dentry *dentry, struct inode *inode, 2299 bool rcu) 2300 { 2301 if (unlikely(IS_PRIVATE(inode))) 2302 return 0; 2303 return call_int_hook(inode_follow_link, dentry, inode, rcu); 2304 } 2305 2306 /** 2307 * security_inode_permission() - Check if accessing an inode is allowed 2308 * @inode: inode 2309 * @mask: access mask 2310 * 2311 * Check permission before accessing an inode. This hook is called by the 2312 * existing Linux permission function, so a security module can use it to 2313 * provide additional checking for existing Linux permission checks. Notice 2314 * that this hook is called when a file is opened (as well as many other 2315 * operations), whereas the file_security_ops permission hook is called when 2316 * the actual read/write operations are performed. 2317 * 2318 * Return: Returns 0 if permission is granted. 2319 */ 2320 int security_inode_permission(struct inode *inode, int mask) 2321 { 2322 if (unlikely(IS_PRIVATE(inode))) 2323 return 0; 2324 return call_int_hook(inode_permission, inode, mask); 2325 } 2326 2327 /** 2328 * security_inode_setattr() - Check if setting file attributes is allowed 2329 * @idmap: idmap of the mount 2330 * @dentry: file 2331 * @attr: new attributes 2332 * 2333 * Check permission before setting file attributes. Note that the kernel call 2334 * to notify_change is performed from several locations, whenever file 2335 * attributes change (such as when a file is truncated, chown/chmod operations, 2336 * transferring disk quotas, etc). 2337 * 2338 * Return: Returns 0 if permission is granted. 2339 */ 2340 int security_inode_setattr(struct mnt_idmap *idmap, 2341 struct dentry *dentry, struct iattr *attr) 2342 { 2343 if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) 2344 return 0; 2345 return call_int_hook(inode_setattr, idmap, dentry, attr); 2346 } 2347 EXPORT_SYMBOL_GPL(security_inode_setattr); 2348 2349 /** 2350 * security_inode_post_setattr() - Update the inode after a setattr operation 2351 * @idmap: idmap of the mount 2352 * @dentry: file 2353 * @ia_valid: file attributes set 2354 * 2355 * Update inode security field after successful setting file attributes. 2356 */ 2357 void security_inode_post_setattr(struct mnt_idmap *idmap, struct dentry *dentry, 2358 int ia_valid) 2359 { 2360 if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) 2361 return; 2362 call_void_hook(inode_post_setattr, idmap, dentry, ia_valid); 2363 } 2364 2365 /** 2366 * security_inode_getattr() - Check if getting file attributes is allowed 2367 * @path: file 2368 * 2369 * Check permission before obtaining file attributes. 2370 * 2371 * Return: Returns 0 if permission is granted. 2372 */ 2373 int security_inode_getattr(const struct path *path) 2374 { 2375 if (unlikely(IS_PRIVATE(d_backing_inode(path->dentry)))) 2376 return 0; 2377 return call_int_hook(inode_getattr, path); 2378 } 2379 2380 /** 2381 * security_inode_setxattr() - Check if setting file xattrs is allowed 2382 * @idmap: idmap of the mount 2383 * @dentry: file 2384 * @name: xattr name 2385 * @value: xattr value 2386 * @size: size of xattr value 2387 * @flags: flags 2388 * 2389 * This hook performs the desired permission checks before setting the extended 2390 * attributes (xattrs) on @dentry. It is important to note that we have some 2391 * additional logic before the main LSM implementation calls to detect if we 2392 * need to perform an additional capability check at the LSM layer. 2393 * 2394 * Normally we enforce a capability check prior to executing the various LSM 2395 * hook implementations, but if a LSM wants to avoid this capability check, 2396 * it can register a 'inode_xattr_skipcap' hook and return a value of 1 for 2397 * xattrs that it wants to avoid the capability check, leaving the LSM fully 2398 * responsible for enforcing the access control for the specific xattr. If all 2399 * of the enabled LSMs refrain from registering a 'inode_xattr_skipcap' hook, 2400 * or return a 0 (the default return value), the capability check is still 2401 * performed. If no 'inode_xattr_skipcap' hooks are registered the capability 2402 * check is performed. 2403 * 2404 * Return: Returns 0 if permission is granted. 2405 */ 2406 int security_inode_setxattr(struct mnt_idmap *idmap, 2407 struct dentry *dentry, const char *name, 2408 const void *value, size_t size, int flags) 2409 { 2410 int rc; 2411 2412 if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) 2413 return 0; 2414 2415 /* enforce the capability checks at the lsm layer, if needed */ 2416 if (!call_int_hook(inode_xattr_skipcap, name)) { 2417 rc = cap_inode_setxattr(dentry, name, value, size, flags); 2418 if (rc) 2419 return rc; 2420 } 2421 2422 return call_int_hook(inode_setxattr, idmap, dentry, name, value, size, 2423 flags); 2424 } 2425 2426 /** 2427 * security_inode_set_acl() - Check if setting posix acls is allowed 2428 * @idmap: idmap of the mount 2429 * @dentry: file 2430 * @acl_name: acl name 2431 * @kacl: acl struct 2432 * 2433 * Check permission before setting posix acls, the posix acls in @kacl are 2434 * identified by @acl_name. 2435 * 2436 * Return: Returns 0 if permission is granted. 2437 */ 2438 int security_inode_set_acl(struct mnt_idmap *idmap, 2439 struct dentry *dentry, const char *acl_name, 2440 struct posix_acl *kacl) 2441 { 2442 if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) 2443 return 0; 2444 return call_int_hook(inode_set_acl, idmap, dentry, acl_name, kacl); 2445 } 2446 2447 /** 2448 * security_inode_post_set_acl() - Update inode security from posix acls set 2449 * @dentry: file 2450 * @acl_name: acl name 2451 * @kacl: acl struct 2452 * 2453 * Update inode security data after successfully setting posix acls on @dentry. 2454 * The posix acls in @kacl are identified by @acl_name. 2455 */ 2456 void security_inode_post_set_acl(struct dentry *dentry, const char *acl_name, 2457 struct posix_acl *kacl) 2458 { 2459 if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) 2460 return; 2461 call_void_hook(inode_post_set_acl, dentry, acl_name, kacl); 2462 } 2463 2464 /** 2465 * security_inode_get_acl() - Check if reading posix acls is allowed 2466 * @idmap: idmap of the mount 2467 * @dentry: file 2468 * @acl_name: acl name 2469 * 2470 * Check permission before getting osix acls, the posix acls are identified by 2471 * @acl_name. 2472 * 2473 * Return: Returns 0 if permission is granted. 2474 */ 2475 int security_inode_get_acl(struct mnt_idmap *idmap, 2476 struct dentry *dentry, const char *acl_name) 2477 { 2478 if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) 2479 return 0; 2480 return call_int_hook(inode_get_acl, idmap, dentry, acl_name); 2481 } 2482 2483 /** 2484 * security_inode_remove_acl() - Check if removing a posix acl is allowed 2485 * @idmap: idmap of the mount 2486 * @dentry: file 2487 * @acl_name: acl name 2488 * 2489 * Check permission before removing posix acls, the posix acls are identified 2490 * by @acl_name. 2491 * 2492 * Return: Returns 0 if permission is granted. 2493 */ 2494 int security_inode_remove_acl(struct mnt_idmap *idmap, 2495 struct dentry *dentry, const char *acl_name) 2496 { 2497 if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) 2498 return 0; 2499 return call_int_hook(inode_remove_acl, idmap, dentry, acl_name); 2500 } 2501 2502 /** 2503 * security_inode_post_remove_acl() - Update inode security after rm posix acls 2504 * @idmap: idmap of the mount 2505 * @dentry: file 2506 * @acl_name: acl name 2507 * 2508 * Update inode security data after successfully removing posix acls on 2509 * @dentry in @idmap. The posix acls are identified by @acl_name. 2510 */ 2511 void security_inode_post_remove_acl(struct mnt_idmap *idmap, 2512 struct dentry *dentry, const char *acl_name) 2513 { 2514 if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) 2515 return; 2516 call_void_hook(inode_post_remove_acl, idmap, dentry, acl_name); 2517 } 2518 2519 /** 2520 * security_inode_post_setxattr() - Update the inode after a setxattr operation 2521 * @dentry: file 2522 * @name: xattr name 2523 * @value: xattr value 2524 * @size: xattr value size 2525 * @flags: flags 2526 * 2527 * Update inode security field after successful setxattr operation. 2528 */ 2529 void security_inode_post_setxattr(struct dentry *dentry, const char *name, 2530 const void *value, size_t size, int flags) 2531 { 2532 if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) 2533 return; 2534 call_void_hook(inode_post_setxattr, dentry, name, value, size, flags); 2535 } 2536 2537 /** 2538 * security_inode_getxattr() - Check if xattr access is allowed 2539 * @dentry: file 2540 * @name: xattr name 2541 * 2542 * Check permission before obtaining the extended attributes identified by 2543 * @name for @dentry. 2544 * 2545 * Return: Returns 0 if permission is granted. 2546 */ 2547 int security_inode_getxattr(struct dentry *dentry, const char *name) 2548 { 2549 if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) 2550 return 0; 2551 return call_int_hook(inode_getxattr, dentry, name); 2552 } 2553 2554 /** 2555 * security_inode_listxattr() - Check if listing xattrs is allowed 2556 * @dentry: file 2557 * 2558 * Check permission before obtaining the list of extended attribute names for 2559 * @dentry. 2560 * 2561 * Return: Returns 0 if permission is granted. 2562 */ 2563 int security_inode_listxattr(struct dentry *dentry) 2564 { 2565 if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) 2566 return 0; 2567 return call_int_hook(inode_listxattr, dentry); 2568 } 2569 2570 /** 2571 * security_inode_removexattr() - Check if removing an xattr is allowed 2572 * @idmap: idmap of the mount 2573 * @dentry: file 2574 * @name: xattr name 2575 * 2576 * This hook performs the desired permission checks before setting the extended 2577 * attributes (xattrs) on @dentry. It is important to note that we have some 2578 * additional logic before the main LSM implementation calls to detect if we 2579 * need to perform an additional capability check at the LSM layer. 2580 * 2581 * Normally we enforce a capability check prior to executing the various LSM 2582 * hook implementations, but if a LSM wants to avoid this capability check, 2583 * it can register a 'inode_xattr_skipcap' hook and return a value of 1 for 2584 * xattrs that it wants to avoid the capability check, leaving the LSM fully 2585 * responsible for enforcing the access control for the specific xattr. If all 2586 * of the enabled LSMs refrain from registering a 'inode_xattr_skipcap' hook, 2587 * or return a 0 (the default return value), the capability check is still 2588 * performed. If no 'inode_xattr_skipcap' hooks are registered the capability 2589 * check is performed. 2590 * 2591 * Return: Returns 0 if permission is granted. 2592 */ 2593 int security_inode_removexattr(struct mnt_idmap *idmap, 2594 struct dentry *dentry, const char *name) 2595 { 2596 int rc; 2597 2598 if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) 2599 return 0; 2600 2601 /* enforce the capability checks at the lsm layer, if needed */ 2602 if (!call_int_hook(inode_xattr_skipcap, name)) { 2603 rc = cap_inode_removexattr(idmap, dentry, name); 2604 if (rc) 2605 return rc; 2606 } 2607 2608 return call_int_hook(inode_removexattr, idmap, dentry, name); 2609 } 2610 2611 /** 2612 * security_inode_post_removexattr() - Update the inode after a removexattr op 2613 * @dentry: file 2614 * @name: xattr name 2615 * 2616 * Update the inode after a successful removexattr operation. 2617 */ 2618 void security_inode_post_removexattr(struct dentry *dentry, const char *name) 2619 { 2620 if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) 2621 return; 2622 call_void_hook(inode_post_removexattr, dentry, name); 2623 } 2624 2625 /** 2626 * security_inode_need_killpriv() - Check if security_inode_killpriv() required 2627 * @dentry: associated dentry 2628 * 2629 * Called when an inode has been changed to determine if 2630 * security_inode_killpriv() should be called. 2631 * 2632 * Return: Return <0 on error to abort the inode change operation, return 0 if 2633 * security_inode_killpriv() does not need to be called, return >0 if 2634 * security_inode_killpriv() does need to be called. 2635 */ 2636 int security_inode_need_killpriv(struct dentry *dentry) 2637 { 2638 return call_int_hook(inode_need_killpriv, dentry); 2639 } 2640 2641 /** 2642 * security_inode_killpriv() - The setuid bit is removed, update LSM state 2643 * @idmap: idmap of the mount 2644 * @dentry: associated dentry 2645 * 2646 * The @dentry's setuid bit is being removed. Remove similar security labels. 2647 * Called with the dentry->d_inode->i_mutex held. 2648 * 2649 * Return: Return 0 on success. If error is returned, then the operation 2650 * causing setuid bit removal is failed. 2651 */ 2652 int security_inode_killpriv(struct mnt_idmap *idmap, 2653 struct dentry *dentry) 2654 { 2655 return call_int_hook(inode_killpriv, idmap, dentry); 2656 } 2657 2658 /** 2659 * security_inode_getsecurity() - Get the xattr security label of an inode 2660 * @idmap: idmap of the mount 2661 * @inode: inode 2662 * @name: xattr name 2663 * @buffer: security label buffer 2664 * @alloc: allocation flag 2665 * 2666 * Retrieve a copy of the extended attribute representation of the security 2667 * label associated with @name for @inode via @buffer. Note that @name is the 2668 * remainder of the attribute name after the security prefix has been removed. 2669 * @alloc is used to specify if the call should return a value via the buffer 2670 * or just the value length. 2671 * 2672 * Return: Returns size of buffer on success. 2673 */ 2674 int security_inode_getsecurity(struct mnt_idmap *idmap, 2675 struct inode *inode, const char *name, 2676 void **buffer, bool alloc) 2677 { 2678 if (unlikely(IS_PRIVATE(inode))) 2679 return LSM_RET_DEFAULT(inode_getsecurity); 2680 2681 return call_int_hook(inode_getsecurity, idmap, inode, name, buffer, 2682 alloc); 2683 } 2684 2685 /** 2686 * security_inode_setsecurity() - Set the xattr security label of an inode 2687 * @inode: inode 2688 * @name: xattr name 2689 * @value: security label 2690 * @size: length of security label 2691 * @flags: flags 2692 * 2693 * Set the security label associated with @name for @inode from the extended 2694 * attribute value @value. @size indicates the size of the @value in bytes. 2695 * @flags may be XATTR_CREATE, XATTR_REPLACE, or 0. Note that @name is the 2696 * remainder of the attribute name after the security. prefix has been removed. 2697 * 2698 * Return: Returns 0 on success. 2699 */ 2700 int security_inode_setsecurity(struct inode *inode, const char *name, 2701 const void *value, size_t size, int flags) 2702 { 2703 if (unlikely(IS_PRIVATE(inode))) 2704 return LSM_RET_DEFAULT(inode_setsecurity); 2705 2706 return call_int_hook(inode_setsecurity, inode, name, value, size, 2707 flags); 2708 } 2709 2710 /** 2711 * security_inode_listsecurity() - List the xattr security label names 2712 * @inode: inode 2713 * @buffer: buffer 2714 * @buffer_size: size of buffer 2715 * 2716 * Copy the extended attribute names for the security labels associated with 2717 * @inode into @buffer. The maximum size of @buffer is specified by 2718 * @buffer_size. @buffer may be NULL to request the size of the buffer 2719 * required. 2720 * 2721 * Return: Returns number of bytes used/required on success. 2722 */ 2723 int security_inode_listsecurity(struct inode *inode, 2724 char *buffer, size_t buffer_size) 2725 { 2726 if (unlikely(IS_PRIVATE(inode))) 2727 return 0; 2728 return call_int_hook(inode_listsecurity, inode, buffer, buffer_size); 2729 } 2730 EXPORT_SYMBOL(security_inode_listsecurity); 2731 2732 /** 2733 * security_inode_getlsmprop() - Get an inode's LSM data 2734 * @inode: inode 2735 * @prop: lsm specific information to return 2736 * 2737 * Get the lsm specific information associated with the node. 2738 */ 2739 void security_inode_getlsmprop(struct inode *inode, struct lsm_prop *prop) 2740 { 2741 call_void_hook(inode_getlsmprop, inode, prop); 2742 } 2743 2744 /** 2745 * security_inode_copy_up() - Create new creds for an overlayfs copy-up op 2746 * @src: union dentry of copy-up file 2747 * @new: newly created creds 2748 * 2749 * A file is about to be copied up from lower layer to upper layer of overlay 2750 * filesystem. Security module can prepare a set of new creds and modify as 2751 * need be and return new creds. Caller will switch to new creds temporarily to 2752 * create new file and release newly allocated creds. 2753 * 2754 * Return: Returns 0 on success or a negative error code on error. 2755 */ 2756 int security_inode_copy_up(struct dentry *src, struct cred **new) 2757 { 2758 return call_int_hook(inode_copy_up, src, new); 2759 } 2760 EXPORT_SYMBOL(security_inode_copy_up); 2761 2762 /** 2763 * security_inode_copy_up_xattr() - Filter xattrs in an overlayfs copy-up op 2764 * @src: union dentry of copy-up file 2765 * @name: xattr name 2766 * 2767 * Filter the xattrs being copied up when a unioned file is copied up from a 2768 * lower layer to the union/overlay layer. The caller is responsible for 2769 * reading and writing the xattrs, this hook is merely a filter. 2770 * 2771 * Return: Returns 0 to accept the xattr, -ECANCELED to discard the xattr, 2772 * -EOPNOTSUPP if the security module does not know about attribute, 2773 * or a negative error code to abort the copy up. 2774 */ 2775 int security_inode_copy_up_xattr(struct dentry *src, const char *name) 2776 { 2777 int rc; 2778 2779 rc = call_int_hook(inode_copy_up_xattr, src, name); 2780 if (rc != LSM_RET_DEFAULT(inode_copy_up_xattr)) 2781 return rc; 2782 2783 return LSM_RET_DEFAULT(inode_copy_up_xattr); 2784 } 2785 EXPORT_SYMBOL(security_inode_copy_up_xattr); 2786 2787 /** 2788 * security_inode_setintegrity() - Set the inode's integrity data 2789 * @inode: inode 2790 * @type: type of integrity, e.g. hash digest, signature, etc 2791 * @value: the integrity value 2792 * @size: size of the integrity value 2793 * 2794 * Register a verified integrity measurement of a inode with LSMs. 2795 * LSMs should free the previously saved data if @value is NULL. 2796 * 2797 * Return: Returns 0 on success, negative values on failure. 2798 */ 2799 int security_inode_setintegrity(const struct inode *inode, 2800 enum lsm_integrity_type type, const void *value, 2801 size_t size) 2802 { 2803 return call_int_hook(inode_setintegrity, inode, type, value, size); 2804 } 2805 EXPORT_SYMBOL(security_inode_setintegrity); 2806 2807 /** 2808 * security_kernfs_init_security() - Init LSM context for a kernfs node 2809 * @kn_dir: parent kernfs node 2810 * @kn: the kernfs node to initialize 2811 * 2812 * Initialize the security context of a newly created kernfs node based on its 2813 * own and its parent's attributes. 2814 * 2815 * Return: Returns 0 if permission is granted. 2816 */ 2817 int security_kernfs_init_security(struct kernfs_node *kn_dir, 2818 struct kernfs_node *kn) 2819 { 2820 return call_int_hook(kernfs_init_security, kn_dir, kn); 2821 } 2822 2823 /** 2824 * security_file_permission() - Check file permissions 2825 * @file: file 2826 * @mask: requested permissions 2827 * 2828 * Check file permissions before accessing an open file. This hook is called 2829 * by various operations that read or write files. A security module can use 2830 * this hook to perform additional checking on these operations, e.g. to 2831 * revalidate permissions on use to support privilege bracketing or policy 2832 * changes. Notice that this hook is used when the actual read/write 2833 * operations are performed, whereas the inode_security_ops hook is called when 2834 * a file is opened (as well as many other operations). Although this hook can 2835 * be used to revalidate permissions for various system call operations that 2836 * read or write files, it does not address the revalidation of permissions for 2837 * memory-mapped files. Security modules must handle this separately if they 2838 * need such revalidation. 2839 * 2840 * Return: Returns 0 if permission is granted. 2841 */ 2842 int security_file_permission(struct file *file, int mask) 2843 { 2844 return call_int_hook(file_permission, file, mask); 2845 } 2846 2847 /** 2848 * security_file_alloc() - Allocate and init a file's LSM blob 2849 * @file: the file 2850 * 2851 * Allocate and attach a security structure to the file->f_security field. The 2852 * security field is initialized to NULL when the structure is first created. 2853 * 2854 * Return: Return 0 if the hook is successful and permission is granted. 2855 */ 2856 int security_file_alloc(struct file *file) 2857 { 2858 int rc = lsm_file_alloc(file); 2859 2860 if (rc) 2861 return rc; 2862 rc = call_int_hook(file_alloc_security, file); 2863 if (unlikely(rc)) 2864 security_file_free(file); 2865 return rc; 2866 } 2867 2868 /** 2869 * security_file_release() - Perform actions before releasing the file ref 2870 * @file: the file 2871 * 2872 * Perform actions before releasing the last reference to a file. 2873 */ 2874 void security_file_release(struct file *file) 2875 { 2876 call_void_hook(file_release, file); 2877 } 2878 2879 /** 2880 * security_file_free() - Free a file's LSM blob 2881 * @file: the file 2882 * 2883 * Deallocate and free any security structures stored in file->f_security. 2884 */ 2885 void security_file_free(struct file *file) 2886 { 2887 void *blob; 2888 2889 call_void_hook(file_free_security, file); 2890 2891 blob = file->f_security; 2892 if (blob) { 2893 file->f_security = NULL; 2894 kmem_cache_free(lsm_file_cache, blob); 2895 } 2896 } 2897 2898 /** 2899 * security_file_ioctl() - Check if an ioctl is allowed 2900 * @file: associated file 2901 * @cmd: ioctl cmd 2902 * @arg: ioctl arguments 2903 * 2904 * Check permission for an ioctl operation on @file. Note that @arg sometimes 2905 * represents a user space pointer; in other cases, it may be a simple integer 2906 * value. When @arg represents a user space pointer, it should never be used 2907 * by the security module. 2908 * 2909 * Return: Returns 0 if permission is granted. 2910 */ 2911 int security_file_ioctl(struct file *file, unsigned int cmd, unsigned long arg) 2912 { 2913 return call_int_hook(file_ioctl, file, cmd, arg); 2914 } 2915 EXPORT_SYMBOL_GPL(security_file_ioctl); 2916 2917 /** 2918 * security_file_ioctl_compat() - Check if an ioctl is allowed in compat mode 2919 * @file: associated file 2920 * @cmd: ioctl cmd 2921 * @arg: ioctl arguments 2922 * 2923 * Compat version of security_file_ioctl() that correctly handles 32-bit 2924 * processes running on 64-bit kernels. 2925 * 2926 * Return: Returns 0 if permission is granted. 2927 */ 2928 int security_file_ioctl_compat(struct file *file, unsigned int cmd, 2929 unsigned long arg) 2930 { 2931 return call_int_hook(file_ioctl_compat, file, cmd, arg); 2932 } 2933 EXPORT_SYMBOL_GPL(security_file_ioctl_compat); 2934 2935 static inline unsigned long mmap_prot(struct file *file, unsigned long prot) 2936 { 2937 /* 2938 * Does we have PROT_READ and does the application expect 2939 * it to imply PROT_EXEC? If not, nothing to talk about... 2940 */ 2941 if ((prot & (PROT_READ | PROT_EXEC)) != PROT_READ) 2942 return prot; 2943 if (!(current->personality & READ_IMPLIES_EXEC)) 2944 return prot; 2945 /* 2946 * if that's an anonymous mapping, let it. 2947 */ 2948 if (!file) 2949 return prot | PROT_EXEC; 2950 /* 2951 * ditto if it's not on noexec mount, except that on !MMU we need 2952 * NOMMU_MAP_EXEC (== VM_MAYEXEC) in this case 2953 */ 2954 if (!path_noexec(&file->f_path)) { 2955 #ifndef CONFIG_MMU 2956 if (file->f_op->mmap_capabilities) { 2957 unsigned caps = file->f_op->mmap_capabilities(file); 2958 if (!(caps & NOMMU_MAP_EXEC)) 2959 return prot; 2960 } 2961 #endif 2962 return prot | PROT_EXEC; 2963 } 2964 /* anything on noexec mount won't get PROT_EXEC */ 2965 return prot; 2966 } 2967 2968 /** 2969 * security_mmap_file() - Check if mmap'ing a file is allowed 2970 * @file: file 2971 * @prot: protection applied by the kernel 2972 * @flags: flags 2973 * 2974 * Check permissions for a mmap operation. The @file may be NULL, e.g. if 2975 * mapping anonymous memory. 2976 * 2977 * Return: Returns 0 if permission is granted. 2978 */ 2979 int security_mmap_file(struct file *file, unsigned long prot, 2980 unsigned long flags) 2981 { 2982 return call_int_hook(mmap_file, file, prot, mmap_prot(file, prot), 2983 flags); 2984 } 2985 2986 /** 2987 * security_mmap_addr() - Check if mmap'ing an address is allowed 2988 * @addr: address 2989 * 2990 * Check permissions for a mmap operation at @addr. 2991 * 2992 * Return: Returns 0 if permission is granted. 2993 */ 2994 int security_mmap_addr(unsigned long addr) 2995 { 2996 return call_int_hook(mmap_addr, addr); 2997 } 2998 2999 /** 3000 * security_file_mprotect() - Check if changing memory protections is allowed 3001 * @vma: memory region 3002 * @reqprot: application requested protection 3003 * @prot: protection applied by the kernel 3004 * 3005 * Check permissions before changing memory access permissions. 3006 * 3007 * Return: Returns 0 if permission is granted. 3008 */ 3009 int security_file_mprotect(struct vm_area_struct *vma, unsigned long reqprot, 3010 unsigned long prot) 3011 { 3012 return call_int_hook(file_mprotect, vma, reqprot, prot); 3013 } 3014 3015 /** 3016 * security_file_lock() - Check if a file lock is allowed 3017 * @file: file 3018 * @cmd: lock operation (e.g. F_RDLCK, F_WRLCK) 3019 * 3020 * Check permission before performing file locking operations. Note the hook 3021 * mediates both flock and fcntl style locks. 3022 * 3023 * Return: Returns 0 if permission is granted. 3024 */ 3025 int security_file_lock(struct file *file, unsigned int cmd) 3026 { 3027 return call_int_hook(file_lock, file, cmd); 3028 } 3029 3030 /** 3031 * security_file_fcntl() - Check if fcntl() op is allowed 3032 * @file: file 3033 * @cmd: fcntl command 3034 * @arg: command argument 3035 * 3036 * Check permission before allowing the file operation specified by @cmd from 3037 * being performed on the file @file. Note that @arg sometimes represents a 3038 * user space pointer; in other cases, it may be a simple integer value. When 3039 * @arg represents a user space pointer, it should never be used by the 3040 * security module. 3041 * 3042 * Return: Returns 0 if permission is granted. 3043 */ 3044 int security_file_fcntl(struct file *file, unsigned int cmd, unsigned long arg) 3045 { 3046 return call_int_hook(file_fcntl, file, cmd, arg); 3047 } 3048 3049 /** 3050 * security_file_set_fowner() - Set the file owner info in the LSM blob 3051 * @file: the file 3052 * 3053 * Save owner security information (typically from current->security) in 3054 * file->f_security for later use by the send_sigiotask hook. 3055 * 3056 * This hook is called with file->f_owner.lock held. 3057 * 3058 * Return: Returns 0 on success. 3059 */ 3060 void security_file_set_fowner(struct file *file) 3061 { 3062 call_void_hook(file_set_fowner, file); 3063 } 3064 3065 /** 3066 * security_file_send_sigiotask() - Check if sending SIGIO/SIGURG is allowed 3067 * @tsk: target task 3068 * @fown: signal sender 3069 * @sig: signal to be sent, SIGIO is sent if 0 3070 * 3071 * Check permission for the file owner @fown to send SIGIO or SIGURG to the 3072 * process @tsk. Note that this hook is sometimes called from interrupt. Note 3073 * that the fown_struct, @fown, is never outside the context of a struct file, 3074 * so the file structure (and associated security information) can always be 3075 * obtained: container_of(fown, struct file, f_owner). 3076 * 3077 * Return: Returns 0 if permission is granted. 3078 */ 3079 int security_file_send_sigiotask(struct task_struct *tsk, 3080 struct fown_struct *fown, int sig) 3081 { 3082 return call_int_hook(file_send_sigiotask, tsk, fown, sig); 3083 } 3084 3085 /** 3086 * security_file_receive() - Check if receiving a file via IPC is allowed 3087 * @file: file being received 3088 * 3089 * This hook allows security modules to control the ability of a process to 3090 * receive an open file descriptor via socket IPC. 3091 * 3092 * Return: Returns 0 if permission is granted. 3093 */ 3094 int security_file_receive(struct file *file) 3095 { 3096 return call_int_hook(file_receive, file); 3097 } 3098 3099 /** 3100 * security_file_open() - Save open() time state for late use by the LSM 3101 * @file: 3102 * 3103 * Save open-time permission checking state for later use upon file_permission, 3104 * and recheck access if anything has changed since inode_permission. 3105 * 3106 * We can check if a file is opened for execution (e.g. execve(2) call), either 3107 * directly or indirectly (e.g. ELF's ld.so) by checking file->f_flags & 3108 * __FMODE_EXEC . 3109 * 3110 * Return: Returns 0 if permission is granted. 3111 */ 3112 int security_file_open(struct file *file) 3113 { 3114 return call_int_hook(file_open, file); 3115 } 3116 3117 /** 3118 * security_file_post_open() - Evaluate a file after it has been opened 3119 * @file: the file 3120 * @mask: access mask 3121 * 3122 * Evaluate an opened file and the access mask requested with open(). The hook 3123 * is useful for LSMs that require the file content to be available in order to 3124 * make decisions. 3125 * 3126 * Return: Returns 0 if permission is granted. 3127 */ 3128 int security_file_post_open(struct file *file, int mask) 3129 { 3130 return call_int_hook(file_post_open, file, mask); 3131 } 3132 EXPORT_SYMBOL_GPL(security_file_post_open); 3133 3134 /** 3135 * security_file_truncate() - Check if truncating a file is allowed 3136 * @file: file 3137 * 3138 * Check permission before truncating a file, i.e. using ftruncate. Note that 3139 * truncation permission may also be checked based on the path, using the 3140 * @path_truncate hook. 3141 * 3142 * Return: Returns 0 if permission is granted. 3143 */ 3144 int security_file_truncate(struct file *file) 3145 { 3146 return call_int_hook(file_truncate, file); 3147 } 3148 3149 /** 3150 * security_task_alloc() - Allocate a task's LSM blob 3151 * @task: the task 3152 * @clone_flags: flags indicating what is being shared 3153 * 3154 * Handle allocation of task-related resources. 3155 * 3156 * Return: Returns a zero on success, negative values on failure. 3157 */ 3158 int security_task_alloc(struct task_struct *task, unsigned long clone_flags) 3159 { 3160 int rc = lsm_task_alloc(task); 3161 3162 if (rc) 3163 return rc; 3164 rc = call_int_hook(task_alloc, task, clone_flags); 3165 if (unlikely(rc)) 3166 security_task_free(task); 3167 return rc; 3168 } 3169 3170 /** 3171 * security_task_free() - Free a task's LSM blob and related resources 3172 * @task: task 3173 * 3174 * Handle release of task-related resources. Note that this can be called from 3175 * interrupt context. 3176 */ 3177 void security_task_free(struct task_struct *task) 3178 { 3179 call_void_hook(task_free, task); 3180 3181 kfree(task->security); 3182 task->security = NULL; 3183 } 3184 3185 /** 3186 * security_cred_alloc_blank() - Allocate the min memory to allow cred_transfer 3187 * @cred: credentials 3188 * @gfp: gfp flags 3189 * 3190 * Only allocate sufficient memory and attach to @cred such that 3191 * cred_transfer() will not get ENOMEM. 3192 * 3193 * Return: Returns 0 on success, negative values on failure. 3194 */ 3195 int security_cred_alloc_blank(struct cred *cred, gfp_t gfp) 3196 { 3197 int rc = lsm_cred_alloc(cred, gfp); 3198 3199 if (rc) 3200 return rc; 3201 3202 rc = call_int_hook(cred_alloc_blank, cred, gfp); 3203 if (unlikely(rc)) 3204 security_cred_free(cred); 3205 return rc; 3206 } 3207 3208 /** 3209 * security_cred_free() - Free the cred's LSM blob and associated resources 3210 * @cred: credentials 3211 * 3212 * Deallocate and clear the cred->security field in a set of credentials. 3213 */ 3214 void security_cred_free(struct cred *cred) 3215 { 3216 /* 3217 * There is a failure case in prepare_creds() that 3218 * may result in a call here with ->security being NULL. 3219 */ 3220 if (unlikely(cred->security == NULL)) 3221 return; 3222 3223 call_void_hook(cred_free, cred); 3224 3225 kfree(cred->security); 3226 cred->security = NULL; 3227 } 3228 3229 /** 3230 * security_prepare_creds() - Prepare a new set of credentials 3231 * @new: new credentials 3232 * @old: original credentials 3233 * @gfp: gfp flags 3234 * 3235 * Prepare a new set of credentials by copying the data from the old set. 3236 * 3237 * Return: Returns 0 on success, negative values on failure. 3238 */ 3239 int security_prepare_creds(struct cred *new, const struct cred *old, gfp_t gfp) 3240 { 3241 int rc = lsm_cred_alloc(new, gfp); 3242 3243 if (rc) 3244 return rc; 3245 3246 rc = call_int_hook(cred_prepare, new, old, gfp); 3247 if (unlikely(rc)) 3248 security_cred_free(new); 3249 return rc; 3250 } 3251 3252 /** 3253 * security_transfer_creds() - Transfer creds 3254 * @new: target credentials 3255 * @old: original credentials 3256 * 3257 * Transfer data from original creds to new creds. 3258 */ 3259 void security_transfer_creds(struct cred *new, const struct cred *old) 3260 { 3261 call_void_hook(cred_transfer, new, old); 3262 } 3263 3264 /** 3265 * security_cred_getsecid() - Get the secid from a set of credentials 3266 * @c: credentials 3267 * @secid: secid value 3268 * 3269 * Retrieve the security identifier of the cred structure @c. In case of 3270 * failure, @secid will be set to zero. 3271 */ 3272 void security_cred_getsecid(const struct cred *c, u32 *secid) 3273 { 3274 *secid = 0; 3275 call_void_hook(cred_getsecid, c, secid); 3276 } 3277 EXPORT_SYMBOL(security_cred_getsecid); 3278 3279 /** 3280 * security_cred_getlsmprop() - Get the LSM data from a set of credentials 3281 * @c: credentials 3282 * @prop: destination for the LSM data 3283 * 3284 * Retrieve the security data of the cred structure @c. In case of 3285 * failure, @prop will be cleared. 3286 */ 3287 void security_cred_getlsmprop(const struct cred *c, struct lsm_prop *prop) 3288 { 3289 lsmprop_init(prop); 3290 call_void_hook(cred_getlsmprop, c, prop); 3291 } 3292 EXPORT_SYMBOL(security_cred_getlsmprop); 3293 3294 /** 3295 * security_kernel_act_as() - Set the kernel credentials to act as secid 3296 * @new: credentials 3297 * @secid: secid 3298 * 3299 * Set the credentials for a kernel service to act as (subjective context). 3300 * The current task must be the one that nominated @secid. 3301 * 3302 * Return: Returns 0 if successful. 3303 */ 3304 int security_kernel_act_as(struct cred *new, u32 secid) 3305 { 3306 return call_int_hook(kernel_act_as, new, secid); 3307 } 3308 3309 /** 3310 * security_kernel_create_files_as() - Set file creation context using an inode 3311 * @new: target credentials 3312 * @inode: reference inode 3313 * 3314 * Set the file creation context in a set of credentials to be the same as the 3315 * objective context of the specified inode. The current task must be the one 3316 * that nominated @inode. 3317 * 3318 * Return: Returns 0 if successful. 3319 */ 3320 int security_kernel_create_files_as(struct cred *new, struct inode *inode) 3321 { 3322 return call_int_hook(kernel_create_files_as, new, inode); 3323 } 3324 3325 /** 3326 * security_kernel_module_request() - Check if loading a module is allowed 3327 * @kmod_name: module name 3328 * 3329 * Ability to trigger the kernel to automatically upcall to userspace for 3330 * userspace to load a kernel module with the given name. 3331 * 3332 * Return: Returns 0 if successful. 3333 */ 3334 int security_kernel_module_request(char *kmod_name) 3335 { 3336 return call_int_hook(kernel_module_request, kmod_name); 3337 } 3338 3339 /** 3340 * security_kernel_read_file() - Read a file specified by userspace 3341 * @file: file 3342 * @id: file identifier 3343 * @contents: trust if security_kernel_post_read_file() will be called 3344 * 3345 * Read a file specified by userspace. 3346 * 3347 * Return: Returns 0 if permission is granted. 3348 */ 3349 int security_kernel_read_file(struct file *file, enum kernel_read_file_id id, 3350 bool contents) 3351 { 3352 return call_int_hook(kernel_read_file, file, id, contents); 3353 } 3354 EXPORT_SYMBOL_GPL(security_kernel_read_file); 3355 3356 /** 3357 * security_kernel_post_read_file() - Read a file specified by userspace 3358 * @file: file 3359 * @buf: file contents 3360 * @size: size of file contents 3361 * @id: file identifier 3362 * 3363 * Read a file specified by userspace. This must be paired with a prior call 3364 * to security_kernel_read_file() call that indicated this hook would also be 3365 * called, see security_kernel_read_file() for more information. 3366 * 3367 * Return: Returns 0 if permission is granted. 3368 */ 3369 int security_kernel_post_read_file(struct file *file, char *buf, loff_t size, 3370 enum kernel_read_file_id id) 3371 { 3372 return call_int_hook(kernel_post_read_file, file, buf, size, id); 3373 } 3374 EXPORT_SYMBOL_GPL(security_kernel_post_read_file); 3375 3376 /** 3377 * security_kernel_load_data() - Load data provided by userspace 3378 * @id: data identifier 3379 * @contents: true if security_kernel_post_load_data() will be called 3380 * 3381 * Load data provided by userspace. 3382 * 3383 * Return: Returns 0 if permission is granted. 3384 */ 3385 int security_kernel_load_data(enum kernel_load_data_id id, bool contents) 3386 { 3387 return call_int_hook(kernel_load_data, id, contents); 3388 } 3389 EXPORT_SYMBOL_GPL(security_kernel_load_data); 3390 3391 /** 3392 * security_kernel_post_load_data() - Load userspace data from a non-file source 3393 * @buf: data 3394 * @size: size of data 3395 * @id: data identifier 3396 * @description: text description of data, specific to the id value 3397 * 3398 * Load data provided by a non-file source (usually userspace buffer). This 3399 * must be paired with a prior security_kernel_load_data() call that indicated 3400 * this hook would also be called, see security_kernel_load_data() for more 3401 * information. 3402 * 3403 * Return: Returns 0 if permission is granted. 3404 */ 3405 int security_kernel_post_load_data(char *buf, loff_t size, 3406 enum kernel_load_data_id id, 3407 char *description) 3408 { 3409 return call_int_hook(kernel_post_load_data, buf, size, id, description); 3410 } 3411 EXPORT_SYMBOL_GPL(security_kernel_post_load_data); 3412 3413 /** 3414 * security_task_fix_setuid() - Update LSM with new user id attributes 3415 * @new: updated credentials 3416 * @old: credentials being replaced 3417 * @flags: LSM_SETID_* flag values 3418 * 3419 * Update the module's state after setting one or more of the user identity 3420 * attributes of the current process. The @flags parameter indicates which of 3421 * the set*uid system calls invoked this hook. If @new is the set of 3422 * credentials that will be installed. Modifications should be made to this 3423 * rather than to @current->cred. 3424 * 3425 * Return: Returns 0 on success. 3426 */ 3427 int security_task_fix_setuid(struct cred *new, const struct cred *old, 3428 int flags) 3429 { 3430 return call_int_hook(task_fix_setuid, new, old, flags); 3431 } 3432 3433 /** 3434 * security_task_fix_setgid() - Update LSM with new group id attributes 3435 * @new: updated credentials 3436 * @old: credentials being replaced 3437 * @flags: LSM_SETID_* flag value 3438 * 3439 * Update the module's state after setting one or more of the group identity 3440 * attributes of the current process. The @flags parameter indicates which of 3441 * the set*gid system calls invoked this hook. @new is the set of credentials 3442 * that will 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_setgid(struct cred *new, const struct cred *old, 3448 int flags) 3449 { 3450 return call_int_hook(task_fix_setgid, new, old, flags); 3451 } 3452 3453 /** 3454 * security_task_fix_setgroups() - Update LSM with new supplementary groups 3455 * @new: updated credentials 3456 * @old: credentials being replaced 3457 * 3458 * Update the module's state after setting the supplementary group identity 3459 * attributes of the current process. @new is the set of credentials that will 3460 * be installed. Modifications should be made to this rather than to 3461 * @current->cred. 3462 * 3463 * Return: Returns 0 on success. 3464 */ 3465 int security_task_fix_setgroups(struct cred *new, const struct cred *old) 3466 { 3467 return call_int_hook(task_fix_setgroups, new, old); 3468 } 3469 3470 /** 3471 * security_task_setpgid() - Check if setting the pgid is allowed 3472 * @p: task being modified 3473 * @pgid: new pgid 3474 * 3475 * Check permission before setting the process group identifier of the process 3476 * @p to @pgid. 3477 * 3478 * Return: Returns 0 if permission is granted. 3479 */ 3480 int security_task_setpgid(struct task_struct *p, pid_t pgid) 3481 { 3482 return call_int_hook(task_setpgid, p, pgid); 3483 } 3484 3485 /** 3486 * security_task_getpgid() - Check if getting the pgid is allowed 3487 * @p: task 3488 * 3489 * Check permission before getting the process group identifier of the process 3490 * @p. 3491 * 3492 * Return: Returns 0 if permission is granted. 3493 */ 3494 int security_task_getpgid(struct task_struct *p) 3495 { 3496 return call_int_hook(task_getpgid, p); 3497 } 3498 3499 /** 3500 * security_task_getsid() - Check if getting the session id is allowed 3501 * @p: task 3502 * 3503 * Check permission before getting the session identifier of the process @p. 3504 * 3505 * Return: Returns 0 if permission is granted. 3506 */ 3507 int security_task_getsid(struct task_struct *p) 3508 { 3509 return call_int_hook(task_getsid, p); 3510 } 3511 3512 /** 3513 * security_current_getlsmprop_subj() - Current task's subjective LSM data 3514 * @prop: lsm specific information 3515 * 3516 * Retrieve the subjective security identifier of the current task and return 3517 * it in @prop. 3518 */ 3519 void security_current_getlsmprop_subj(struct lsm_prop *prop) 3520 { 3521 lsmprop_init(prop); 3522 call_void_hook(current_getlsmprop_subj, prop); 3523 } 3524 EXPORT_SYMBOL(security_current_getlsmprop_subj); 3525 3526 /** 3527 * security_task_getlsmprop_obj() - Get a task's objective LSM data 3528 * @p: target task 3529 * @prop: lsm specific information 3530 * 3531 * Retrieve the objective security identifier of the task_struct in @p and 3532 * return it in @prop. 3533 */ 3534 void security_task_getlsmprop_obj(struct task_struct *p, struct lsm_prop *prop) 3535 { 3536 lsmprop_init(prop); 3537 call_void_hook(task_getlsmprop_obj, p, prop); 3538 } 3539 EXPORT_SYMBOL(security_task_getlsmprop_obj); 3540 3541 /** 3542 * security_task_setnice() - Check if setting a task's nice value is allowed 3543 * @p: target task 3544 * @nice: nice value 3545 * 3546 * Check permission before setting the nice value of @p to @nice. 3547 * 3548 * Return: Returns 0 if permission is granted. 3549 */ 3550 int security_task_setnice(struct task_struct *p, int nice) 3551 { 3552 return call_int_hook(task_setnice, p, nice); 3553 } 3554 3555 /** 3556 * security_task_setioprio() - Check if setting a task's ioprio is allowed 3557 * @p: target task 3558 * @ioprio: ioprio value 3559 * 3560 * Check permission before setting the ioprio value of @p to @ioprio. 3561 * 3562 * Return: Returns 0 if permission is granted. 3563 */ 3564 int security_task_setioprio(struct task_struct *p, int ioprio) 3565 { 3566 return call_int_hook(task_setioprio, p, ioprio); 3567 } 3568 3569 /** 3570 * security_task_getioprio() - Check if getting a task's ioprio is allowed 3571 * @p: task 3572 * 3573 * Check permission before getting the ioprio value of @p. 3574 * 3575 * Return: Returns 0 if permission is granted. 3576 */ 3577 int security_task_getioprio(struct task_struct *p) 3578 { 3579 return call_int_hook(task_getioprio, p); 3580 } 3581 3582 /** 3583 * security_task_prlimit() - Check if get/setting resources limits is allowed 3584 * @cred: current task credentials 3585 * @tcred: target task credentials 3586 * @flags: LSM_PRLIMIT_* flag bits indicating a get/set/both 3587 * 3588 * Check permission before getting and/or setting the resource limits of 3589 * another task. 3590 * 3591 * Return: Returns 0 if permission is granted. 3592 */ 3593 int security_task_prlimit(const struct cred *cred, const struct cred *tcred, 3594 unsigned int flags) 3595 { 3596 return call_int_hook(task_prlimit, cred, tcred, flags); 3597 } 3598 3599 /** 3600 * security_task_setrlimit() - Check if setting a new rlimit value is allowed 3601 * @p: target task's group leader 3602 * @resource: resource whose limit is being set 3603 * @new_rlim: new resource limit 3604 * 3605 * Check permission before setting the resource limits of process @p for 3606 * @resource to @new_rlim. The old resource limit values can be examined by 3607 * dereferencing (p->signal->rlim + resource). 3608 * 3609 * Return: Returns 0 if permission is granted. 3610 */ 3611 int security_task_setrlimit(struct task_struct *p, unsigned int resource, 3612 struct rlimit *new_rlim) 3613 { 3614 return call_int_hook(task_setrlimit, p, resource, new_rlim); 3615 } 3616 3617 /** 3618 * security_task_setscheduler() - Check if setting sched policy/param is allowed 3619 * @p: target task 3620 * 3621 * Check permission before setting scheduling policy and/or parameters of 3622 * process @p. 3623 * 3624 * Return: Returns 0 if permission is granted. 3625 */ 3626 int security_task_setscheduler(struct task_struct *p) 3627 { 3628 return call_int_hook(task_setscheduler, p); 3629 } 3630 3631 /** 3632 * security_task_getscheduler() - Check if getting scheduling info is allowed 3633 * @p: target task 3634 * 3635 * Check permission before obtaining scheduling information for process @p. 3636 * 3637 * Return: Returns 0 if permission is granted. 3638 */ 3639 int security_task_getscheduler(struct task_struct *p) 3640 { 3641 return call_int_hook(task_getscheduler, p); 3642 } 3643 3644 /** 3645 * security_task_movememory() - Check if moving memory is allowed 3646 * @p: task 3647 * 3648 * Check permission before moving memory owned by process @p. 3649 * 3650 * Return: Returns 0 if permission is granted. 3651 */ 3652 int security_task_movememory(struct task_struct *p) 3653 { 3654 return call_int_hook(task_movememory, p); 3655 } 3656 3657 /** 3658 * security_task_kill() - Check if sending a signal is allowed 3659 * @p: target process 3660 * @info: signal information 3661 * @sig: signal value 3662 * @cred: credentials of the signal sender, NULL if @current 3663 * 3664 * Check permission before sending signal @sig to @p. @info can be NULL, the 3665 * constant 1, or a pointer to a kernel_siginfo structure. If @info is 1 or 3666 * SI_FROMKERNEL(info) is true, then the signal should be viewed as coming from 3667 * the kernel and should typically be permitted. SIGIO signals are handled 3668 * separately by the send_sigiotask hook in file_security_ops. 3669 * 3670 * Return: Returns 0 if permission is granted. 3671 */ 3672 int security_task_kill(struct task_struct *p, struct kernel_siginfo *info, 3673 int sig, const struct cred *cred) 3674 { 3675 return call_int_hook(task_kill, p, info, sig, cred); 3676 } 3677 3678 /** 3679 * security_task_prctl() - Check if a prctl op is allowed 3680 * @option: operation 3681 * @arg2: argument 3682 * @arg3: argument 3683 * @arg4: argument 3684 * @arg5: argument 3685 * 3686 * Check permission before performing a process control operation on the 3687 * current process. 3688 * 3689 * Return: Return -ENOSYS if no-one wanted to handle this op, any other value 3690 * to cause prctl() to return immediately with that value. 3691 */ 3692 int security_task_prctl(int option, unsigned long arg2, unsigned long arg3, 3693 unsigned long arg4, unsigned long arg5) 3694 { 3695 int thisrc; 3696 int rc = LSM_RET_DEFAULT(task_prctl); 3697 struct lsm_static_call *scall; 3698 3699 lsm_for_each_hook(scall, task_prctl) { 3700 thisrc = scall->hl->hook.task_prctl(option, arg2, arg3, arg4, arg5); 3701 if (thisrc != LSM_RET_DEFAULT(task_prctl)) { 3702 rc = thisrc; 3703 if (thisrc != 0) 3704 break; 3705 } 3706 } 3707 return rc; 3708 } 3709 3710 /** 3711 * security_task_to_inode() - Set the security attributes of a task's inode 3712 * @p: task 3713 * @inode: inode 3714 * 3715 * Set the security attributes for an inode based on an associated task's 3716 * security attributes, e.g. for /proc/pid inodes. 3717 */ 3718 void security_task_to_inode(struct task_struct *p, struct inode *inode) 3719 { 3720 call_void_hook(task_to_inode, p, inode); 3721 } 3722 3723 /** 3724 * security_create_user_ns() - Check if creating a new userns is allowed 3725 * @cred: prepared creds 3726 * 3727 * Check permission prior to creating a new user namespace. 3728 * 3729 * Return: Returns 0 if successful, otherwise < 0 error code. 3730 */ 3731 int security_create_user_ns(const struct cred *cred) 3732 { 3733 return call_int_hook(userns_create, cred); 3734 } 3735 3736 /** 3737 * security_ipc_permission() - Check if sysv ipc access is allowed 3738 * @ipcp: ipc permission structure 3739 * @flag: requested permissions 3740 * 3741 * Check permissions for access to IPC. 3742 * 3743 * Return: Returns 0 if permission is granted. 3744 */ 3745 int security_ipc_permission(struct kern_ipc_perm *ipcp, short flag) 3746 { 3747 return call_int_hook(ipc_permission, ipcp, flag); 3748 } 3749 3750 /** 3751 * security_ipc_getlsmprop() - Get the sysv ipc object LSM data 3752 * @ipcp: ipc permission structure 3753 * @prop: pointer to lsm information 3754 * 3755 * Get the lsm information associated with the ipc object. 3756 */ 3757 3758 void security_ipc_getlsmprop(struct kern_ipc_perm *ipcp, struct lsm_prop *prop) 3759 { 3760 lsmprop_init(prop); 3761 call_void_hook(ipc_getlsmprop, ipcp, prop); 3762 } 3763 3764 /** 3765 * security_msg_msg_alloc() - Allocate a sysv ipc message LSM blob 3766 * @msg: message structure 3767 * 3768 * Allocate and attach a security structure to the msg->security field. The 3769 * security field is initialized to NULL when the structure is first created. 3770 * 3771 * Return: Return 0 if operation was successful and permission is granted. 3772 */ 3773 int security_msg_msg_alloc(struct msg_msg *msg) 3774 { 3775 int rc = lsm_msg_msg_alloc(msg); 3776 3777 if (unlikely(rc)) 3778 return rc; 3779 rc = call_int_hook(msg_msg_alloc_security, msg); 3780 if (unlikely(rc)) 3781 security_msg_msg_free(msg); 3782 return rc; 3783 } 3784 3785 /** 3786 * security_msg_msg_free() - Free a sysv ipc message LSM blob 3787 * @msg: message structure 3788 * 3789 * Deallocate the security structure for this message. 3790 */ 3791 void security_msg_msg_free(struct msg_msg *msg) 3792 { 3793 call_void_hook(msg_msg_free_security, msg); 3794 kfree(msg->security); 3795 msg->security = NULL; 3796 } 3797 3798 /** 3799 * security_msg_queue_alloc() - Allocate a sysv ipc msg queue LSM blob 3800 * @msq: sysv ipc permission structure 3801 * 3802 * Allocate and attach a security structure to @msg. The security field is 3803 * initialized to NULL when the structure is first created. 3804 * 3805 * Return: Returns 0 if operation was successful and permission is granted. 3806 */ 3807 int security_msg_queue_alloc(struct kern_ipc_perm *msq) 3808 { 3809 int rc = lsm_ipc_alloc(msq); 3810 3811 if (unlikely(rc)) 3812 return rc; 3813 rc = call_int_hook(msg_queue_alloc_security, msq); 3814 if (unlikely(rc)) 3815 security_msg_queue_free(msq); 3816 return rc; 3817 } 3818 3819 /** 3820 * security_msg_queue_free() - Free a sysv ipc msg queue LSM blob 3821 * @msq: sysv ipc permission structure 3822 * 3823 * Deallocate security field @perm->security for the message queue. 3824 */ 3825 void security_msg_queue_free(struct kern_ipc_perm *msq) 3826 { 3827 call_void_hook(msg_queue_free_security, msq); 3828 kfree(msq->security); 3829 msq->security = NULL; 3830 } 3831 3832 /** 3833 * security_msg_queue_associate() - Check if a msg queue operation is allowed 3834 * @msq: sysv ipc permission structure 3835 * @msqflg: operation flags 3836 * 3837 * Check permission when a message queue is requested through the msgget system 3838 * call. This hook is only called when returning the message queue identifier 3839 * for an existing message queue, not when a new message queue is created. 3840 * 3841 * Return: Return 0 if permission is granted. 3842 */ 3843 int security_msg_queue_associate(struct kern_ipc_perm *msq, int msqflg) 3844 { 3845 return call_int_hook(msg_queue_associate, msq, msqflg); 3846 } 3847 3848 /** 3849 * security_msg_queue_msgctl() - Check if a msg queue operation is allowed 3850 * @msq: sysv ipc permission structure 3851 * @cmd: operation 3852 * 3853 * Check permission when a message control operation specified by @cmd is to be 3854 * performed on the message queue with permissions. 3855 * 3856 * Return: Returns 0 if permission is granted. 3857 */ 3858 int security_msg_queue_msgctl(struct kern_ipc_perm *msq, int cmd) 3859 { 3860 return call_int_hook(msg_queue_msgctl, msq, cmd); 3861 } 3862 3863 /** 3864 * security_msg_queue_msgsnd() - Check if sending a sysv ipc message is allowed 3865 * @msq: sysv ipc permission structure 3866 * @msg: message 3867 * @msqflg: operation flags 3868 * 3869 * Check permission before a message, @msg, is enqueued on the message queue 3870 * with permissions specified in @msq. 3871 * 3872 * Return: Returns 0 if permission is granted. 3873 */ 3874 int security_msg_queue_msgsnd(struct kern_ipc_perm *msq, 3875 struct msg_msg *msg, int msqflg) 3876 { 3877 return call_int_hook(msg_queue_msgsnd, msq, msg, msqflg); 3878 } 3879 3880 /** 3881 * security_msg_queue_msgrcv() - Check if receiving a sysv ipc msg is allowed 3882 * @msq: sysv ipc permission structure 3883 * @msg: message 3884 * @target: target task 3885 * @type: type of message requested 3886 * @mode: operation flags 3887 * 3888 * Check permission before a message, @msg, is removed from the message queue. 3889 * The @target task structure contains a pointer to the process that will be 3890 * receiving the message (not equal to the current process when inline receives 3891 * are being performed). 3892 * 3893 * Return: Returns 0 if permission is granted. 3894 */ 3895 int security_msg_queue_msgrcv(struct kern_ipc_perm *msq, struct msg_msg *msg, 3896 struct task_struct *target, long type, int mode) 3897 { 3898 return call_int_hook(msg_queue_msgrcv, msq, msg, target, type, mode); 3899 } 3900 3901 /** 3902 * security_shm_alloc() - Allocate a sysv shm LSM blob 3903 * @shp: sysv ipc permission structure 3904 * 3905 * Allocate and attach a security structure to the @shp security field. The 3906 * security field is initialized to NULL when the structure is first created. 3907 * 3908 * Return: Returns 0 if operation was successful and permission is granted. 3909 */ 3910 int security_shm_alloc(struct kern_ipc_perm *shp) 3911 { 3912 int rc = lsm_ipc_alloc(shp); 3913 3914 if (unlikely(rc)) 3915 return rc; 3916 rc = call_int_hook(shm_alloc_security, shp); 3917 if (unlikely(rc)) 3918 security_shm_free(shp); 3919 return rc; 3920 } 3921 3922 /** 3923 * security_shm_free() - Free a sysv shm LSM blob 3924 * @shp: sysv ipc permission structure 3925 * 3926 * Deallocate the security structure @perm->security for the memory segment. 3927 */ 3928 void security_shm_free(struct kern_ipc_perm *shp) 3929 { 3930 call_void_hook(shm_free_security, shp); 3931 kfree(shp->security); 3932 shp->security = NULL; 3933 } 3934 3935 /** 3936 * security_shm_associate() - Check if a sysv shm operation is allowed 3937 * @shp: sysv ipc permission structure 3938 * @shmflg: operation flags 3939 * 3940 * Check permission when a shared memory region is requested through the shmget 3941 * system call. This hook is only called when returning the shared memory 3942 * region identifier for an existing region, not when a new shared memory 3943 * region is created. 3944 * 3945 * Return: Returns 0 if permission is granted. 3946 */ 3947 int security_shm_associate(struct kern_ipc_perm *shp, int shmflg) 3948 { 3949 return call_int_hook(shm_associate, shp, shmflg); 3950 } 3951 3952 /** 3953 * security_shm_shmctl() - Check if a sysv shm operation is allowed 3954 * @shp: sysv ipc permission structure 3955 * @cmd: operation 3956 * 3957 * Check permission when a shared memory control operation specified by @cmd is 3958 * to be performed on the shared memory region with permissions in @shp. 3959 * 3960 * Return: Return 0 if permission is granted. 3961 */ 3962 int security_shm_shmctl(struct kern_ipc_perm *shp, int cmd) 3963 { 3964 return call_int_hook(shm_shmctl, shp, cmd); 3965 } 3966 3967 /** 3968 * security_shm_shmat() - Check if a sysv shm attach operation is allowed 3969 * @shp: sysv ipc permission structure 3970 * @shmaddr: address of memory region to attach 3971 * @shmflg: operation flags 3972 * 3973 * Check permissions prior to allowing the shmat system call to attach the 3974 * shared memory segment with permissions @shp to the data segment of the 3975 * calling process. The attaching address is specified by @shmaddr. 3976 * 3977 * Return: Returns 0 if permission is granted. 3978 */ 3979 int security_shm_shmat(struct kern_ipc_perm *shp, 3980 char __user *shmaddr, int shmflg) 3981 { 3982 return call_int_hook(shm_shmat, shp, shmaddr, shmflg); 3983 } 3984 3985 /** 3986 * security_sem_alloc() - Allocate a sysv semaphore LSM blob 3987 * @sma: sysv ipc permission structure 3988 * 3989 * Allocate and attach a security structure to the @sma security field. The 3990 * security field is initialized to NULL when the structure is first created. 3991 * 3992 * Return: Returns 0 if operation was successful and permission is granted. 3993 */ 3994 int security_sem_alloc(struct kern_ipc_perm *sma) 3995 { 3996 int rc = lsm_ipc_alloc(sma); 3997 3998 if (unlikely(rc)) 3999 return rc; 4000 rc = call_int_hook(sem_alloc_security, sma); 4001 if (unlikely(rc)) 4002 security_sem_free(sma); 4003 return rc; 4004 } 4005 4006 /** 4007 * security_sem_free() - Free a sysv semaphore LSM blob 4008 * @sma: sysv ipc permission structure 4009 * 4010 * Deallocate security structure @sma->security for the semaphore. 4011 */ 4012 void security_sem_free(struct kern_ipc_perm *sma) 4013 { 4014 call_void_hook(sem_free_security, sma); 4015 kfree(sma->security); 4016 sma->security = NULL; 4017 } 4018 4019 /** 4020 * security_sem_associate() - Check if a sysv semaphore operation is allowed 4021 * @sma: sysv ipc permission structure 4022 * @semflg: operation flags 4023 * 4024 * Check permission when a semaphore is requested through the semget system 4025 * call. This hook is only called when returning the semaphore identifier for 4026 * an existing semaphore, not when a new one must be created. 4027 * 4028 * Return: Returns 0 if permission is granted. 4029 */ 4030 int security_sem_associate(struct kern_ipc_perm *sma, int semflg) 4031 { 4032 return call_int_hook(sem_associate, sma, semflg); 4033 } 4034 4035 /** 4036 * security_sem_semctl() - Check if a sysv semaphore operation is allowed 4037 * @sma: sysv ipc permission structure 4038 * @cmd: operation 4039 * 4040 * Check permission when a semaphore operation specified by @cmd is to be 4041 * performed on the semaphore. 4042 * 4043 * Return: Returns 0 if permission is granted. 4044 */ 4045 int security_sem_semctl(struct kern_ipc_perm *sma, int cmd) 4046 { 4047 return call_int_hook(sem_semctl, sma, cmd); 4048 } 4049 4050 /** 4051 * security_sem_semop() - Check if a sysv semaphore operation is allowed 4052 * @sma: sysv ipc permission structure 4053 * @sops: operations to perform 4054 * @nsops: number of operations 4055 * @alter: flag indicating changes will be made 4056 * 4057 * Check permissions before performing operations on members of the semaphore 4058 * set. If the @alter flag is nonzero, the semaphore set may be modified. 4059 * 4060 * Return: Returns 0 if permission is granted. 4061 */ 4062 int security_sem_semop(struct kern_ipc_perm *sma, struct sembuf *sops, 4063 unsigned nsops, int alter) 4064 { 4065 return call_int_hook(sem_semop, sma, sops, nsops, alter); 4066 } 4067 4068 /** 4069 * security_d_instantiate() - Populate an inode's LSM state based on a dentry 4070 * @dentry: dentry 4071 * @inode: inode 4072 * 4073 * Fill in @inode security information for a @dentry if allowed. 4074 */ 4075 void security_d_instantiate(struct dentry *dentry, struct inode *inode) 4076 { 4077 if (unlikely(inode && IS_PRIVATE(inode))) 4078 return; 4079 call_void_hook(d_instantiate, dentry, inode); 4080 } 4081 EXPORT_SYMBOL(security_d_instantiate); 4082 4083 /* 4084 * Please keep this in sync with it's counterpart in security/lsm_syscalls.c 4085 */ 4086 4087 /** 4088 * security_getselfattr - Read an LSM attribute of the current process. 4089 * @attr: which attribute to return 4090 * @uctx: the user-space destination for the information, or NULL 4091 * @size: pointer to the size of space available to receive the data 4092 * @flags: special handling options. LSM_FLAG_SINGLE indicates that only 4093 * attributes associated with the LSM identified in the passed @ctx be 4094 * reported. 4095 * 4096 * A NULL value for @uctx can be used to get both the number of attributes 4097 * and the size of the data. 4098 * 4099 * Returns the number of attributes found on success, negative value 4100 * on error. @size is reset to the total size of the data. 4101 * If @size is insufficient to contain the data -E2BIG is returned. 4102 */ 4103 int security_getselfattr(unsigned int attr, struct lsm_ctx __user *uctx, 4104 u32 __user *size, u32 flags) 4105 { 4106 struct lsm_static_call *scall; 4107 struct lsm_ctx lctx = { .id = LSM_ID_UNDEF, }; 4108 u8 __user *base = (u8 __user *)uctx; 4109 u32 entrysize; 4110 u32 total = 0; 4111 u32 left; 4112 bool toobig = false; 4113 bool single = false; 4114 int count = 0; 4115 int rc; 4116 4117 if (attr == LSM_ATTR_UNDEF) 4118 return -EINVAL; 4119 if (size == NULL) 4120 return -EINVAL; 4121 if (get_user(left, size)) 4122 return -EFAULT; 4123 4124 if (flags) { 4125 /* 4126 * Only flag supported is LSM_FLAG_SINGLE 4127 */ 4128 if (flags != LSM_FLAG_SINGLE || !uctx) 4129 return -EINVAL; 4130 if (copy_from_user(&lctx, uctx, sizeof(lctx))) 4131 return -EFAULT; 4132 /* 4133 * If the LSM ID isn't specified it is an error. 4134 */ 4135 if (lctx.id == LSM_ID_UNDEF) 4136 return -EINVAL; 4137 single = true; 4138 } 4139 4140 /* 4141 * In the usual case gather all the data from the LSMs. 4142 * In the single case only get the data from the LSM specified. 4143 */ 4144 lsm_for_each_hook(scall, getselfattr) { 4145 if (single && lctx.id != scall->hl->lsmid->id) 4146 continue; 4147 entrysize = left; 4148 if (base) 4149 uctx = (struct lsm_ctx __user *)(base + total); 4150 rc = scall->hl->hook.getselfattr(attr, uctx, &entrysize, flags); 4151 if (rc == -EOPNOTSUPP) 4152 continue; 4153 if (rc == -E2BIG) { 4154 rc = 0; 4155 left = 0; 4156 toobig = true; 4157 } else if (rc < 0) 4158 return rc; 4159 else 4160 left -= entrysize; 4161 4162 total += entrysize; 4163 count += rc; 4164 if (single) 4165 break; 4166 } 4167 if (put_user(total, size)) 4168 return -EFAULT; 4169 if (toobig) 4170 return -E2BIG; 4171 if (count == 0) 4172 return LSM_RET_DEFAULT(getselfattr); 4173 return count; 4174 } 4175 4176 /* 4177 * Please keep this in sync with it's counterpart in security/lsm_syscalls.c 4178 */ 4179 4180 /** 4181 * security_setselfattr - Set an LSM attribute on the current process. 4182 * @attr: which attribute to set 4183 * @uctx: the user-space source for the information 4184 * @size: the size of the data 4185 * @flags: reserved for future use, must be 0 4186 * 4187 * Set an LSM attribute for the current process. The LSM, attribute 4188 * and new value are included in @uctx. 4189 * 4190 * Returns 0 on success, -EINVAL if the input is inconsistent, -EFAULT 4191 * if the user buffer is inaccessible, E2BIG if size is too big, or an 4192 * LSM specific failure. 4193 */ 4194 int security_setselfattr(unsigned int attr, struct lsm_ctx __user *uctx, 4195 u32 size, u32 flags) 4196 { 4197 struct lsm_static_call *scall; 4198 struct lsm_ctx *lctx; 4199 int rc = LSM_RET_DEFAULT(setselfattr); 4200 u64 required_len; 4201 4202 if (flags) 4203 return -EINVAL; 4204 if (size < sizeof(*lctx)) 4205 return -EINVAL; 4206 if (size > PAGE_SIZE) 4207 return -E2BIG; 4208 4209 lctx = memdup_user(uctx, size); 4210 if (IS_ERR(lctx)) 4211 return PTR_ERR(lctx); 4212 4213 if (size < lctx->len || 4214 check_add_overflow(sizeof(*lctx), lctx->ctx_len, &required_len) || 4215 lctx->len < required_len) { 4216 rc = -EINVAL; 4217 goto free_out; 4218 } 4219 4220 lsm_for_each_hook(scall, setselfattr) 4221 if ((scall->hl->lsmid->id) == lctx->id) { 4222 rc = scall->hl->hook.setselfattr(attr, lctx, size, flags); 4223 break; 4224 } 4225 4226 free_out: 4227 kfree(lctx); 4228 return rc; 4229 } 4230 4231 /** 4232 * security_getprocattr() - Read an attribute for a task 4233 * @p: the task 4234 * @lsmid: LSM identification 4235 * @name: attribute name 4236 * @value: attribute value 4237 * 4238 * Read attribute @name for task @p and store it into @value if allowed. 4239 * 4240 * Return: Returns the length of @value on success, a negative value otherwise. 4241 */ 4242 int security_getprocattr(struct task_struct *p, int lsmid, const char *name, 4243 char **value) 4244 { 4245 struct lsm_static_call *scall; 4246 4247 lsm_for_each_hook(scall, getprocattr) { 4248 if (lsmid != 0 && lsmid != scall->hl->lsmid->id) 4249 continue; 4250 return scall->hl->hook.getprocattr(p, name, value); 4251 } 4252 return LSM_RET_DEFAULT(getprocattr); 4253 } 4254 4255 /** 4256 * security_setprocattr() - Set an attribute for a task 4257 * @lsmid: LSM identification 4258 * @name: attribute name 4259 * @value: attribute value 4260 * @size: attribute value size 4261 * 4262 * Write (set) the current task's attribute @name to @value, size @size if 4263 * allowed. 4264 * 4265 * Return: Returns bytes written on success, a negative value otherwise. 4266 */ 4267 int security_setprocattr(int lsmid, const char *name, void *value, size_t size) 4268 { 4269 struct lsm_static_call *scall; 4270 4271 lsm_for_each_hook(scall, setprocattr) { 4272 if (lsmid != 0 && lsmid != scall->hl->lsmid->id) 4273 continue; 4274 return scall->hl->hook.setprocattr(name, value, size); 4275 } 4276 return LSM_RET_DEFAULT(setprocattr); 4277 } 4278 4279 /** 4280 * security_netlink_send() - Save info and check if netlink sending is allowed 4281 * @sk: sending socket 4282 * @skb: netlink message 4283 * 4284 * Save security information for a netlink message so that permission checking 4285 * can be performed when the message is processed. The security information 4286 * can be saved using the eff_cap field of the netlink_skb_parms structure. 4287 * Also may be used to provide fine grained control over message transmission. 4288 * 4289 * Return: Returns 0 if the information was successfully saved and message is 4290 * allowed to be transmitted. 4291 */ 4292 int security_netlink_send(struct sock *sk, struct sk_buff *skb) 4293 { 4294 return call_int_hook(netlink_send, sk, skb); 4295 } 4296 4297 /** 4298 * security_ismaclabel() - Check if the named attribute is a MAC label 4299 * @name: full extended attribute name 4300 * 4301 * Check if the extended attribute specified by @name represents a MAC label. 4302 * 4303 * Return: Returns 1 if name is a MAC attribute otherwise returns 0. 4304 */ 4305 int security_ismaclabel(const char *name) 4306 { 4307 return call_int_hook(ismaclabel, name); 4308 } 4309 EXPORT_SYMBOL(security_ismaclabel); 4310 4311 /** 4312 * security_secid_to_secctx() - Convert a secid to a secctx 4313 * @secid: secid 4314 * @cp: the LSM context 4315 * 4316 * Convert secid to security context. If @cp is NULL the length of the 4317 * result will be returned, but no data will be returned. This 4318 * does mean that the length could change between calls to check the length and 4319 * the next call which actually allocates and returns the data. 4320 * 4321 * Return: Return length of data on success, error on failure. 4322 */ 4323 int security_secid_to_secctx(u32 secid, struct lsm_context *cp) 4324 { 4325 return call_int_hook(secid_to_secctx, secid, cp); 4326 } 4327 EXPORT_SYMBOL(security_secid_to_secctx); 4328 4329 /** 4330 * security_lsmprop_to_secctx() - Convert a lsm_prop to a secctx 4331 * @prop: lsm specific information 4332 * @cp: the LSM context 4333 * 4334 * Convert a @prop entry to security context. If @cp is NULL the 4335 * length of the result will be returned. This does mean that the 4336 * length could change between calls to check the length and the 4337 * next call which actually allocates and returns the @cp. 4338 * 4339 * Return: Return length of data on success, error on failure. 4340 */ 4341 int security_lsmprop_to_secctx(struct lsm_prop *prop, struct lsm_context *cp) 4342 { 4343 return call_int_hook(lsmprop_to_secctx, prop, cp); 4344 } 4345 EXPORT_SYMBOL(security_lsmprop_to_secctx); 4346 4347 /** 4348 * security_secctx_to_secid() - Convert a secctx to a secid 4349 * @secdata: secctx 4350 * @seclen: length of secctx 4351 * @secid: secid 4352 * 4353 * Convert security context to secid. 4354 * 4355 * Return: Returns 0 on success, error on failure. 4356 */ 4357 int security_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid) 4358 { 4359 *secid = 0; 4360 return call_int_hook(secctx_to_secid, secdata, seclen, secid); 4361 } 4362 EXPORT_SYMBOL(security_secctx_to_secid); 4363 4364 /** 4365 * security_release_secctx() - Free a secctx buffer 4366 * @cp: the security context 4367 * 4368 * Release the security context. 4369 */ 4370 void security_release_secctx(struct lsm_context *cp) 4371 { 4372 call_void_hook(release_secctx, cp); 4373 memset(cp, 0, sizeof(*cp)); 4374 } 4375 EXPORT_SYMBOL(security_release_secctx); 4376 4377 /** 4378 * security_inode_invalidate_secctx() - Invalidate an inode's security label 4379 * @inode: inode 4380 * 4381 * Notify the security module that it must revalidate the security context of 4382 * an inode. 4383 */ 4384 void security_inode_invalidate_secctx(struct inode *inode) 4385 { 4386 call_void_hook(inode_invalidate_secctx, inode); 4387 } 4388 EXPORT_SYMBOL(security_inode_invalidate_secctx); 4389 4390 /** 4391 * security_inode_notifysecctx() - Notify the LSM of an inode's security label 4392 * @inode: inode 4393 * @ctx: secctx 4394 * @ctxlen: length of secctx 4395 * 4396 * Notify the security module of what the security context of an inode should 4397 * be. Initializes the incore security context managed by the security module 4398 * for this inode. Example usage: NFS client invokes this hook to initialize 4399 * the security context in its incore inode to the value provided by the server 4400 * for the file when the server returned the file's attributes to the client. 4401 * Must be called with inode->i_mutex locked. 4402 * 4403 * Return: Returns 0 on success, error on failure. 4404 */ 4405 int security_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen) 4406 { 4407 return call_int_hook(inode_notifysecctx, inode, ctx, ctxlen); 4408 } 4409 EXPORT_SYMBOL(security_inode_notifysecctx); 4410 4411 /** 4412 * security_inode_setsecctx() - Change the security label of an inode 4413 * @dentry: inode 4414 * @ctx: secctx 4415 * @ctxlen: length of secctx 4416 * 4417 * Change the security context of an inode. Updates the incore security 4418 * context managed by the security module and invokes the fs code as needed 4419 * (via __vfs_setxattr_noperm) to update any backing xattrs that represent the 4420 * context. Example usage: NFS server invokes this hook to change the security 4421 * context in its incore inode and on the backing filesystem to a value 4422 * provided by the client on a SETATTR operation. Must be called with 4423 * inode->i_mutex locked. 4424 * 4425 * Return: Returns 0 on success, error on failure. 4426 */ 4427 int security_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen) 4428 { 4429 return call_int_hook(inode_setsecctx, dentry, ctx, ctxlen); 4430 } 4431 EXPORT_SYMBOL(security_inode_setsecctx); 4432 4433 /** 4434 * security_inode_getsecctx() - Get the security label of an inode 4435 * @inode: inode 4436 * @cp: security context 4437 * 4438 * On success, returns 0 and fills out @cp with the security context 4439 * for the given @inode. 4440 * 4441 * Return: Returns 0 on success, error on failure. 4442 */ 4443 int security_inode_getsecctx(struct inode *inode, struct lsm_context *cp) 4444 { 4445 memset(cp, 0, sizeof(*cp)); 4446 return call_int_hook(inode_getsecctx, inode, cp); 4447 } 4448 EXPORT_SYMBOL(security_inode_getsecctx); 4449 4450 #ifdef CONFIG_WATCH_QUEUE 4451 /** 4452 * security_post_notification() - Check if a watch notification can be posted 4453 * @w_cred: credentials of the task that set the watch 4454 * @cred: credentials of the task which triggered the watch 4455 * @n: the notification 4456 * 4457 * Check to see if a watch notification can be posted to a particular queue. 4458 * 4459 * Return: Returns 0 if permission is granted. 4460 */ 4461 int security_post_notification(const struct cred *w_cred, 4462 const struct cred *cred, 4463 struct watch_notification *n) 4464 { 4465 return call_int_hook(post_notification, w_cred, cred, n); 4466 } 4467 #endif /* CONFIG_WATCH_QUEUE */ 4468 4469 #ifdef CONFIG_KEY_NOTIFICATIONS 4470 /** 4471 * security_watch_key() - Check if a task is allowed to watch for key events 4472 * @key: the key to watch 4473 * 4474 * Check to see if a process is allowed to watch for event notifications from 4475 * a key or keyring. 4476 * 4477 * Return: Returns 0 if permission is granted. 4478 */ 4479 int security_watch_key(struct key *key) 4480 { 4481 return call_int_hook(watch_key, key); 4482 } 4483 #endif /* CONFIG_KEY_NOTIFICATIONS */ 4484 4485 #ifdef CONFIG_SECURITY_NETWORK 4486 /** 4487 * security_unix_stream_connect() - Check if a AF_UNIX stream is allowed 4488 * @sock: originating sock 4489 * @other: peer sock 4490 * @newsk: new sock 4491 * 4492 * Check permissions before establishing a Unix domain stream connection 4493 * between @sock and @other. 4494 * 4495 * The @unix_stream_connect and @unix_may_send hooks were necessary because 4496 * Linux provides an alternative to the conventional file name space for Unix 4497 * domain sockets. Whereas binding and connecting to sockets in the file name 4498 * space is mediated by the typical file permissions (and caught by the mknod 4499 * and permission hooks in inode_security_ops), binding and connecting to 4500 * sockets in the abstract name space is completely unmediated. Sufficient 4501 * control of Unix domain sockets in the abstract name space isn't possible 4502 * using only the socket layer hooks, since we need to know the actual target 4503 * socket, which is not looked up until we are inside the af_unix code. 4504 * 4505 * Return: Returns 0 if permission is granted. 4506 */ 4507 int security_unix_stream_connect(struct sock *sock, struct sock *other, 4508 struct sock *newsk) 4509 { 4510 return call_int_hook(unix_stream_connect, sock, other, newsk); 4511 } 4512 EXPORT_SYMBOL(security_unix_stream_connect); 4513 4514 /** 4515 * security_unix_may_send() - Check if AF_UNIX socket can send datagrams 4516 * @sock: originating sock 4517 * @other: peer sock 4518 * 4519 * Check permissions before connecting or sending datagrams from @sock to 4520 * @other. 4521 * 4522 * The @unix_stream_connect and @unix_may_send hooks were necessary because 4523 * Linux provides an alternative to the conventional file name space for Unix 4524 * domain sockets. Whereas binding and connecting to sockets in the file name 4525 * space is mediated by the typical file permissions (and caught by the mknod 4526 * and permission hooks in inode_security_ops), binding and connecting to 4527 * sockets in the abstract name space is completely unmediated. Sufficient 4528 * control of Unix domain sockets in the abstract name space isn't possible 4529 * using only the socket layer hooks, since we need to know the actual target 4530 * socket, which is not looked up until we are inside the af_unix code. 4531 * 4532 * Return: Returns 0 if permission is granted. 4533 */ 4534 int security_unix_may_send(struct socket *sock, struct socket *other) 4535 { 4536 return call_int_hook(unix_may_send, sock, other); 4537 } 4538 EXPORT_SYMBOL(security_unix_may_send); 4539 4540 /** 4541 * security_socket_create() - Check if creating a new socket is allowed 4542 * @family: protocol family 4543 * @type: communications type 4544 * @protocol: requested protocol 4545 * @kern: set to 1 if a kernel socket is requested 4546 * 4547 * Check permissions prior to creating a new socket. 4548 * 4549 * Return: Returns 0 if permission is granted. 4550 */ 4551 int security_socket_create(int family, int type, int protocol, int kern) 4552 { 4553 return call_int_hook(socket_create, family, type, protocol, kern); 4554 } 4555 4556 /** 4557 * security_socket_post_create() - Initialize a newly created socket 4558 * @sock: socket 4559 * @family: protocol family 4560 * @type: communications type 4561 * @protocol: requested protocol 4562 * @kern: set to 1 if a kernel socket is requested 4563 * 4564 * This hook allows a module to update or allocate a per-socket security 4565 * structure. Note that the security field was not added directly to the socket 4566 * structure, but rather, the socket security information is stored in the 4567 * associated inode. Typically, the inode alloc_security hook will allocate 4568 * and attach security information to SOCK_INODE(sock)->i_security. This hook 4569 * may be used to update the SOCK_INODE(sock)->i_security field with additional 4570 * information that wasn't available when the inode was allocated. 4571 * 4572 * Return: Returns 0 if permission is granted. 4573 */ 4574 int security_socket_post_create(struct socket *sock, int family, 4575 int type, int protocol, int kern) 4576 { 4577 return call_int_hook(socket_post_create, sock, family, type, 4578 protocol, kern); 4579 } 4580 4581 /** 4582 * security_socket_socketpair() - Check if creating a socketpair is allowed 4583 * @socka: first socket 4584 * @sockb: second socket 4585 * 4586 * Check permissions before creating a fresh pair of sockets. 4587 * 4588 * Return: Returns 0 if permission is granted and the connection was 4589 * established. 4590 */ 4591 int security_socket_socketpair(struct socket *socka, struct socket *sockb) 4592 { 4593 return call_int_hook(socket_socketpair, socka, sockb); 4594 } 4595 EXPORT_SYMBOL(security_socket_socketpair); 4596 4597 /** 4598 * security_socket_bind() - Check if a socket bind operation is allowed 4599 * @sock: socket 4600 * @address: requested bind address 4601 * @addrlen: length of address 4602 * 4603 * Check permission before socket protocol layer bind operation is performed 4604 * and the socket @sock is bound to the address specified in the @address 4605 * parameter. 4606 * 4607 * Return: Returns 0 if permission is granted. 4608 */ 4609 int security_socket_bind(struct socket *sock, 4610 struct sockaddr *address, int addrlen) 4611 { 4612 return call_int_hook(socket_bind, sock, address, addrlen); 4613 } 4614 4615 /** 4616 * security_socket_connect() - Check if a socket connect operation is allowed 4617 * @sock: socket 4618 * @address: address of remote connection point 4619 * @addrlen: length of address 4620 * 4621 * Check permission before socket protocol layer connect operation attempts to 4622 * connect socket @sock to a remote address, @address. 4623 * 4624 * Return: Returns 0 if permission is granted. 4625 */ 4626 int security_socket_connect(struct socket *sock, 4627 struct sockaddr *address, int addrlen) 4628 { 4629 return call_int_hook(socket_connect, sock, address, addrlen); 4630 } 4631 4632 /** 4633 * security_socket_listen() - Check if a socket is allowed to listen 4634 * @sock: socket 4635 * @backlog: connection queue size 4636 * 4637 * Check permission before socket protocol layer listen operation. 4638 * 4639 * Return: Returns 0 if permission is granted. 4640 */ 4641 int security_socket_listen(struct socket *sock, int backlog) 4642 { 4643 return call_int_hook(socket_listen, sock, backlog); 4644 } 4645 4646 /** 4647 * security_socket_accept() - Check if a socket is allowed to accept connections 4648 * @sock: listening socket 4649 * @newsock: newly creation connection socket 4650 * 4651 * Check permission before accepting a new connection. Note that the new 4652 * socket, @newsock, has been created and some information copied to it, but 4653 * the accept operation has not actually been performed. 4654 * 4655 * Return: Returns 0 if permission is granted. 4656 */ 4657 int security_socket_accept(struct socket *sock, struct socket *newsock) 4658 { 4659 return call_int_hook(socket_accept, sock, newsock); 4660 } 4661 4662 /** 4663 * security_socket_sendmsg() - Check if sending a message is allowed 4664 * @sock: sending socket 4665 * @msg: message to send 4666 * @size: size of message 4667 * 4668 * Check permission before transmitting a message to another socket. 4669 * 4670 * Return: Returns 0 if permission is granted. 4671 */ 4672 int security_socket_sendmsg(struct socket *sock, struct msghdr *msg, int size) 4673 { 4674 return call_int_hook(socket_sendmsg, sock, msg, size); 4675 } 4676 4677 /** 4678 * security_socket_recvmsg() - Check if receiving a message is allowed 4679 * @sock: receiving socket 4680 * @msg: message to receive 4681 * @size: size of message 4682 * @flags: operational flags 4683 * 4684 * Check permission before receiving a message from a socket. 4685 * 4686 * Return: Returns 0 if permission is granted. 4687 */ 4688 int security_socket_recvmsg(struct socket *sock, struct msghdr *msg, 4689 int size, int flags) 4690 { 4691 return call_int_hook(socket_recvmsg, sock, msg, size, flags); 4692 } 4693 4694 /** 4695 * security_socket_getsockname() - Check if reading the socket addr is allowed 4696 * @sock: socket 4697 * 4698 * Check permission before reading the local address (name) of the socket 4699 * object. 4700 * 4701 * Return: Returns 0 if permission is granted. 4702 */ 4703 int security_socket_getsockname(struct socket *sock) 4704 { 4705 return call_int_hook(socket_getsockname, sock); 4706 } 4707 4708 /** 4709 * security_socket_getpeername() - Check if reading the peer's addr is allowed 4710 * @sock: socket 4711 * 4712 * Check permission before the remote address (name) of a socket object. 4713 * 4714 * Return: Returns 0 if permission is granted. 4715 */ 4716 int security_socket_getpeername(struct socket *sock) 4717 { 4718 return call_int_hook(socket_getpeername, sock); 4719 } 4720 4721 /** 4722 * security_socket_getsockopt() - Check if reading a socket option is allowed 4723 * @sock: socket 4724 * @level: option's protocol level 4725 * @optname: option name 4726 * 4727 * Check permissions before retrieving the options associated with socket 4728 * @sock. 4729 * 4730 * Return: Returns 0 if permission is granted. 4731 */ 4732 int security_socket_getsockopt(struct socket *sock, int level, int optname) 4733 { 4734 return call_int_hook(socket_getsockopt, sock, level, optname); 4735 } 4736 4737 /** 4738 * security_socket_setsockopt() - Check if setting a socket option is allowed 4739 * @sock: socket 4740 * @level: option's protocol level 4741 * @optname: option name 4742 * 4743 * Check permissions before setting the options associated with socket @sock. 4744 * 4745 * Return: Returns 0 if permission is granted. 4746 */ 4747 int security_socket_setsockopt(struct socket *sock, int level, int optname) 4748 { 4749 return call_int_hook(socket_setsockopt, sock, level, optname); 4750 } 4751 4752 /** 4753 * security_socket_shutdown() - Checks if shutting down the socket is allowed 4754 * @sock: socket 4755 * @how: flag indicating how sends and receives are handled 4756 * 4757 * Checks permission before all or part of a connection on the socket @sock is 4758 * shut down. 4759 * 4760 * Return: Returns 0 if permission is granted. 4761 */ 4762 int security_socket_shutdown(struct socket *sock, int how) 4763 { 4764 return call_int_hook(socket_shutdown, sock, how); 4765 } 4766 4767 /** 4768 * security_sock_rcv_skb() - Check if an incoming network packet is allowed 4769 * @sk: destination sock 4770 * @skb: incoming packet 4771 * 4772 * Check permissions on incoming network packets. This hook is distinct from 4773 * Netfilter's IP input hooks since it is the first time that the incoming 4774 * sk_buff @skb has been associated with a particular socket, @sk. Must not 4775 * sleep inside this hook because some callers hold spinlocks. 4776 * 4777 * Return: Returns 0 if permission is granted. 4778 */ 4779 int security_sock_rcv_skb(struct sock *sk, struct sk_buff *skb) 4780 { 4781 return call_int_hook(socket_sock_rcv_skb, sk, skb); 4782 } 4783 EXPORT_SYMBOL(security_sock_rcv_skb); 4784 4785 /** 4786 * security_socket_getpeersec_stream() - Get the remote peer label 4787 * @sock: socket 4788 * @optval: destination buffer 4789 * @optlen: size of peer label copied into the buffer 4790 * @len: maximum size of the destination buffer 4791 * 4792 * This hook allows the security module to provide peer socket security state 4793 * for unix or connected tcp sockets to userspace via getsockopt SO_GETPEERSEC. 4794 * For tcp sockets this can be meaningful if the socket is associated with an 4795 * ipsec SA. 4796 * 4797 * Return: Returns 0 if all is well, otherwise, typical getsockopt return 4798 * values. 4799 */ 4800 int security_socket_getpeersec_stream(struct socket *sock, sockptr_t optval, 4801 sockptr_t optlen, unsigned int len) 4802 { 4803 return call_int_hook(socket_getpeersec_stream, sock, optval, optlen, 4804 len); 4805 } 4806 4807 /** 4808 * security_socket_getpeersec_dgram() - Get the remote peer label 4809 * @sock: socket 4810 * @skb: datagram packet 4811 * @secid: remote peer label secid 4812 * 4813 * This hook allows the security module to provide peer socket security state 4814 * for udp sockets on a per-packet basis to userspace via getsockopt 4815 * SO_GETPEERSEC. The application must first have indicated the IP_PASSSEC 4816 * option via getsockopt. It can then retrieve the security state returned by 4817 * this hook for a packet via the SCM_SECURITY ancillary message type. 4818 * 4819 * Return: Returns 0 on success, error on failure. 4820 */ 4821 int security_socket_getpeersec_dgram(struct socket *sock, 4822 struct sk_buff *skb, u32 *secid) 4823 { 4824 return call_int_hook(socket_getpeersec_dgram, sock, skb, secid); 4825 } 4826 EXPORT_SYMBOL(security_socket_getpeersec_dgram); 4827 4828 /** 4829 * lsm_sock_alloc - allocate a composite sock blob 4830 * @sock: the sock that needs a blob 4831 * @gfp: allocation mode 4832 * 4833 * Allocate the sock blob for all the modules 4834 * 4835 * Returns 0, or -ENOMEM if memory can't be allocated. 4836 */ 4837 static int lsm_sock_alloc(struct sock *sock, gfp_t gfp) 4838 { 4839 return lsm_blob_alloc(&sock->sk_security, blob_sizes.lbs_sock, gfp); 4840 } 4841 4842 /** 4843 * security_sk_alloc() - Allocate and initialize a sock's LSM blob 4844 * @sk: sock 4845 * @family: protocol family 4846 * @priority: gfp flags 4847 * 4848 * Allocate and attach a security structure to the sk->sk_security field, which 4849 * is used to copy security attributes between local stream sockets. 4850 * 4851 * Return: Returns 0 on success, error on failure. 4852 */ 4853 int security_sk_alloc(struct sock *sk, int family, gfp_t priority) 4854 { 4855 int rc = lsm_sock_alloc(sk, priority); 4856 4857 if (unlikely(rc)) 4858 return rc; 4859 rc = call_int_hook(sk_alloc_security, sk, family, priority); 4860 if (unlikely(rc)) 4861 security_sk_free(sk); 4862 return rc; 4863 } 4864 4865 /** 4866 * security_sk_free() - Free the sock's LSM blob 4867 * @sk: sock 4868 * 4869 * Deallocate security structure. 4870 */ 4871 void security_sk_free(struct sock *sk) 4872 { 4873 call_void_hook(sk_free_security, sk); 4874 kfree(sk->sk_security); 4875 sk->sk_security = NULL; 4876 } 4877 4878 /** 4879 * security_sk_clone() - Clone a sock's LSM state 4880 * @sk: original sock 4881 * @newsk: target sock 4882 * 4883 * Clone/copy security structure. 4884 */ 4885 void security_sk_clone(const struct sock *sk, struct sock *newsk) 4886 { 4887 call_void_hook(sk_clone_security, sk, newsk); 4888 } 4889 EXPORT_SYMBOL(security_sk_clone); 4890 4891 /** 4892 * security_sk_classify_flow() - Set a flow's secid based on socket 4893 * @sk: original socket 4894 * @flic: target flow 4895 * 4896 * Set the target flow's secid to socket's secid. 4897 */ 4898 void security_sk_classify_flow(const struct sock *sk, struct flowi_common *flic) 4899 { 4900 call_void_hook(sk_getsecid, sk, &flic->flowic_secid); 4901 } 4902 EXPORT_SYMBOL(security_sk_classify_flow); 4903 4904 /** 4905 * security_req_classify_flow() - Set a flow's secid based on request_sock 4906 * @req: request_sock 4907 * @flic: target flow 4908 * 4909 * Sets @flic's secid to @req's secid. 4910 */ 4911 void security_req_classify_flow(const struct request_sock *req, 4912 struct flowi_common *flic) 4913 { 4914 call_void_hook(req_classify_flow, req, flic); 4915 } 4916 EXPORT_SYMBOL(security_req_classify_flow); 4917 4918 /** 4919 * security_sock_graft() - Reconcile LSM state when grafting a sock on a socket 4920 * @sk: sock being grafted 4921 * @parent: target parent socket 4922 * 4923 * Sets @parent's inode secid to @sk's secid and update @sk with any necessary 4924 * LSM state from @parent. 4925 */ 4926 void security_sock_graft(struct sock *sk, struct socket *parent) 4927 { 4928 call_void_hook(sock_graft, sk, parent); 4929 } 4930 EXPORT_SYMBOL(security_sock_graft); 4931 4932 /** 4933 * security_inet_conn_request() - Set request_sock state using incoming connect 4934 * @sk: parent listening sock 4935 * @skb: incoming connection 4936 * @req: new request_sock 4937 * 4938 * Initialize the @req LSM state based on @sk and the incoming connect in @skb. 4939 * 4940 * Return: Returns 0 if permission is granted. 4941 */ 4942 int security_inet_conn_request(const struct sock *sk, 4943 struct sk_buff *skb, struct request_sock *req) 4944 { 4945 return call_int_hook(inet_conn_request, sk, skb, req); 4946 } 4947 EXPORT_SYMBOL(security_inet_conn_request); 4948 4949 /** 4950 * security_inet_csk_clone() - Set new sock LSM state based on request_sock 4951 * @newsk: new sock 4952 * @req: connection request_sock 4953 * 4954 * Set that LSM state of @sock using the LSM state from @req. 4955 */ 4956 void security_inet_csk_clone(struct sock *newsk, 4957 const struct request_sock *req) 4958 { 4959 call_void_hook(inet_csk_clone, newsk, req); 4960 } 4961 4962 /** 4963 * security_inet_conn_established() - Update sock's LSM state with connection 4964 * @sk: sock 4965 * @skb: connection packet 4966 * 4967 * Update @sock's LSM state to represent a new connection from @skb. 4968 */ 4969 void security_inet_conn_established(struct sock *sk, 4970 struct sk_buff *skb) 4971 { 4972 call_void_hook(inet_conn_established, sk, skb); 4973 } 4974 EXPORT_SYMBOL(security_inet_conn_established); 4975 4976 /** 4977 * security_secmark_relabel_packet() - Check if setting a secmark is allowed 4978 * @secid: new secmark value 4979 * 4980 * Check if the process should be allowed to relabel packets to @secid. 4981 * 4982 * Return: Returns 0 if permission is granted. 4983 */ 4984 int security_secmark_relabel_packet(u32 secid) 4985 { 4986 return call_int_hook(secmark_relabel_packet, secid); 4987 } 4988 EXPORT_SYMBOL(security_secmark_relabel_packet); 4989 4990 /** 4991 * security_secmark_refcount_inc() - Increment the secmark labeling rule count 4992 * 4993 * Tells the LSM to increment the number of secmark labeling rules loaded. 4994 */ 4995 void security_secmark_refcount_inc(void) 4996 { 4997 call_void_hook(secmark_refcount_inc); 4998 } 4999 EXPORT_SYMBOL(security_secmark_refcount_inc); 5000 5001 /** 5002 * security_secmark_refcount_dec() - Decrement the secmark labeling rule count 5003 * 5004 * Tells the LSM to decrement the number of secmark labeling rules loaded. 5005 */ 5006 void security_secmark_refcount_dec(void) 5007 { 5008 call_void_hook(secmark_refcount_dec); 5009 } 5010 EXPORT_SYMBOL(security_secmark_refcount_dec); 5011 5012 /** 5013 * security_tun_dev_alloc_security() - Allocate a LSM blob for a TUN device 5014 * @security: pointer to the LSM blob 5015 * 5016 * This hook allows a module to allocate a security structure for a TUN device, 5017 * returning the pointer in @security. 5018 * 5019 * Return: Returns a zero on success, negative values on failure. 5020 */ 5021 int security_tun_dev_alloc_security(void **security) 5022 { 5023 int rc; 5024 5025 rc = lsm_blob_alloc(security, blob_sizes.lbs_tun_dev, GFP_KERNEL); 5026 if (rc) 5027 return rc; 5028 5029 rc = call_int_hook(tun_dev_alloc_security, *security); 5030 if (rc) { 5031 kfree(*security); 5032 *security = NULL; 5033 } 5034 return rc; 5035 } 5036 EXPORT_SYMBOL(security_tun_dev_alloc_security); 5037 5038 /** 5039 * security_tun_dev_free_security() - Free a TUN device LSM blob 5040 * @security: LSM blob 5041 * 5042 * This hook allows a module to free the security structure for a TUN device. 5043 */ 5044 void security_tun_dev_free_security(void *security) 5045 { 5046 kfree(security); 5047 } 5048 EXPORT_SYMBOL(security_tun_dev_free_security); 5049 5050 /** 5051 * security_tun_dev_create() - Check if creating a TUN device is allowed 5052 * 5053 * Check permissions prior to creating a new TUN device. 5054 * 5055 * Return: Returns 0 if permission is granted. 5056 */ 5057 int security_tun_dev_create(void) 5058 { 5059 return call_int_hook(tun_dev_create); 5060 } 5061 EXPORT_SYMBOL(security_tun_dev_create); 5062 5063 /** 5064 * security_tun_dev_attach_queue() - Check if attaching a TUN queue is allowed 5065 * @security: TUN device LSM blob 5066 * 5067 * Check permissions prior to attaching to a TUN device queue. 5068 * 5069 * Return: Returns 0 if permission is granted. 5070 */ 5071 int security_tun_dev_attach_queue(void *security) 5072 { 5073 return call_int_hook(tun_dev_attach_queue, security); 5074 } 5075 EXPORT_SYMBOL(security_tun_dev_attach_queue); 5076 5077 /** 5078 * security_tun_dev_attach() - Update TUN device LSM state on attach 5079 * @sk: associated sock 5080 * @security: TUN device LSM blob 5081 * 5082 * This hook can be used by the module to update any security state associated 5083 * with the TUN device's sock structure. 5084 * 5085 * Return: Returns 0 if permission is granted. 5086 */ 5087 int security_tun_dev_attach(struct sock *sk, void *security) 5088 { 5089 return call_int_hook(tun_dev_attach, sk, security); 5090 } 5091 EXPORT_SYMBOL(security_tun_dev_attach); 5092 5093 /** 5094 * security_tun_dev_open() - Update TUN device LSM state on open 5095 * @security: TUN device LSM blob 5096 * 5097 * This hook can be used by the module to update any security state associated 5098 * with the TUN device's security structure. 5099 * 5100 * Return: Returns 0 if permission is granted. 5101 */ 5102 int security_tun_dev_open(void *security) 5103 { 5104 return call_int_hook(tun_dev_open, security); 5105 } 5106 EXPORT_SYMBOL(security_tun_dev_open); 5107 5108 /** 5109 * security_sctp_assoc_request() - Update the LSM on a SCTP association req 5110 * @asoc: SCTP association 5111 * @skb: packet requesting the association 5112 * 5113 * Passes the @asoc and @chunk->skb of the association INIT packet to the LSM. 5114 * 5115 * Return: Returns 0 on success, error on failure. 5116 */ 5117 int security_sctp_assoc_request(struct sctp_association *asoc, 5118 struct sk_buff *skb) 5119 { 5120 return call_int_hook(sctp_assoc_request, asoc, skb); 5121 } 5122 EXPORT_SYMBOL(security_sctp_assoc_request); 5123 5124 /** 5125 * security_sctp_bind_connect() - Validate a list of addrs for a SCTP option 5126 * @sk: socket 5127 * @optname: SCTP option to validate 5128 * @address: list of IP addresses to validate 5129 * @addrlen: length of the address list 5130 * 5131 * Validiate permissions required for each address associated with sock @sk. 5132 * Depending on @optname, the addresses will be treated as either a connect or 5133 * bind service. The @addrlen is calculated on each IPv4 and IPv6 address using 5134 * sizeof(struct sockaddr_in) or sizeof(struct sockaddr_in6). 5135 * 5136 * Return: Returns 0 on success, error on failure. 5137 */ 5138 int security_sctp_bind_connect(struct sock *sk, int optname, 5139 struct sockaddr *address, int addrlen) 5140 { 5141 return call_int_hook(sctp_bind_connect, sk, optname, address, addrlen); 5142 } 5143 EXPORT_SYMBOL(security_sctp_bind_connect); 5144 5145 /** 5146 * security_sctp_sk_clone() - Clone a SCTP sock's LSM state 5147 * @asoc: SCTP association 5148 * @sk: original sock 5149 * @newsk: target sock 5150 * 5151 * Called whenever a new socket is created by accept(2) (i.e. a TCP style 5152 * socket) or when a socket is 'peeled off' e.g userspace calls 5153 * sctp_peeloff(3). 5154 */ 5155 void security_sctp_sk_clone(struct sctp_association *asoc, struct sock *sk, 5156 struct sock *newsk) 5157 { 5158 call_void_hook(sctp_sk_clone, asoc, sk, newsk); 5159 } 5160 EXPORT_SYMBOL(security_sctp_sk_clone); 5161 5162 /** 5163 * security_sctp_assoc_established() - Update LSM state when assoc established 5164 * @asoc: SCTP association 5165 * @skb: packet establishing the association 5166 * 5167 * Passes the @asoc and @chunk->skb of the association COOKIE_ACK packet to the 5168 * security module. 5169 * 5170 * Return: Returns 0 if permission is granted. 5171 */ 5172 int security_sctp_assoc_established(struct sctp_association *asoc, 5173 struct sk_buff *skb) 5174 { 5175 return call_int_hook(sctp_assoc_established, asoc, skb); 5176 } 5177 EXPORT_SYMBOL(security_sctp_assoc_established); 5178 5179 /** 5180 * security_mptcp_add_subflow() - Inherit the LSM label from the MPTCP socket 5181 * @sk: the owning MPTCP socket 5182 * @ssk: the new subflow 5183 * 5184 * Update the labeling for the given MPTCP subflow, to match the one of the 5185 * owning MPTCP socket. This hook has to be called after the socket creation and 5186 * initialization via the security_socket_create() and 5187 * security_socket_post_create() LSM hooks. 5188 * 5189 * Return: Returns 0 on success or a negative error code on failure. 5190 */ 5191 int security_mptcp_add_subflow(struct sock *sk, struct sock *ssk) 5192 { 5193 return call_int_hook(mptcp_add_subflow, sk, ssk); 5194 } 5195 5196 #endif /* CONFIG_SECURITY_NETWORK */ 5197 5198 #ifdef CONFIG_SECURITY_INFINIBAND 5199 /** 5200 * security_ib_pkey_access() - Check if access to an IB pkey is allowed 5201 * @sec: LSM blob 5202 * @subnet_prefix: subnet prefix of the port 5203 * @pkey: IB pkey 5204 * 5205 * Check permission to access a pkey when modifying a QP. 5206 * 5207 * Return: Returns 0 if permission is granted. 5208 */ 5209 int security_ib_pkey_access(void *sec, u64 subnet_prefix, u16 pkey) 5210 { 5211 return call_int_hook(ib_pkey_access, sec, subnet_prefix, pkey); 5212 } 5213 EXPORT_SYMBOL(security_ib_pkey_access); 5214 5215 /** 5216 * security_ib_endport_manage_subnet() - Check if SMPs traffic is allowed 5217 * @sec: LSM blob 5218 * @dev_name: IB device name 5219 * @port_num: port number 5220 * 5221 * Check permissions to send and receive SMPs on a end port. 5222 * 5223 * Return: Returns 0 if permission is granted. 5224 */ 5225 int security_ib_endport_manage_subnet(void *sec, 5226 const char *dev_name, u8 port_num) 5227 { 5228 return call_int_hook(ib_endport_manage_subnet, sec, dev_name, port_num); 5229 } 5230 EXPORT_SYMBOL(security_ib_endport_manage_subnet); 5231 5232 /** 5233 * security_ib_alloc_security() - Allocate an Infiniband LSM blob 5234 * @sec: LSM blob 5235 * 5236 * Allocate a security structure for Infiniband objects. 5237 * 5238 * Return: Returns 0 on success, non-zero on failure. 5239 */ 5240 int security_ib_alloc_security(void **sec) 5241 { 5242 int rc; 5243 5244 rc = lsm_blob_alloc(sec, blob_sizes.lbs_ib, GFP_KERNEL); 5245 if (rc) 5246 return rc; 5247 5248 rc = call_int_hook(ib_alloc_security, *sec); 5249 if (rc) { 5250 kfree(*sec); 5251 *sec = NULL; 5252 } 5253 return rc; 5254 } 5255 EXPORT_SYMBOL(security_ib_alloc_security); 5256 5257 /** 5258 * security_ib_free_security() - Free an Infiniband LSM blob 5259 * @sec: LSM blob 5260 * 5261 * Deallocate an Infiniband security structure. 5262 */ 5263 void security_ib_free_security(void *sec) 5264 { 5265 kfree(sec); 5266 } 5267 EXPORT_SYMBOL(security_ib_free_security); 5268 #endif /* CONFIG_SECURITY_INFINIBAND */ 5269 5270 #ifdef CONFIG_SECURITY_NETWORK_XFRM 5271 /** 5272 * security_xfrm_policy_alloc() - Allocate a xfrm policy LSM blob 5273 * @ctxp: xfrm security context being added to the SPD 5274 * @sec_ctx: security label provided by userspace 5275 * @gfp: gfp flags 5276 * 5277 * Allocate a security structure to the xp->security field; the security field 5278 * is initialized to NULL when the xfrm_policy is allocated. 5279 * 5280 * Return: Return 0 if operation was successful. 5281 */ 5282 int security_xfrm_policy_alloc(struct xfrm_sec_ctx **ctxp, 5283 struct xfrm_user_sec_ctx *sec_ctx, 5284 gfp_t gfp) 5285 { 5286 return call_int_hook(xfrm_policy_alloc_security, ctxp, sec_ctx, gfp); 5287 } 5288 EXPORT_SYMBOL(security_xfrm_policy_alloc); 5289 5290 /** 5291 * security_xfrm_policy_clone() - Clone xfrm policy LSM state 5292 * @old_ctx: xfrm security context 5293 * @new_ctxp: target xfrm security context 5294 * 5295 * Allocate a security structure in new_ctxp that contains the information from 5296 * the old_ctx structure. 5297 * 5298 * Return: Return 0 if operation was successful. 5299 */ 5300 int security_xfrm_policy_clone(struct xfrm_sec_ctx *old_ctx, 5301 struct xfrm_sec_ctx **new_ctxp) 5302 { 5303 return call_int_hook(xfrm_policy_clone_security, old_ctx, new_ctxp); 5304 } 5305 5306 /** 5307 * security_xfrm_policy_free() - Free a xfrm security context 5308 * @ctx: xfrm security context 5309 * 5310 * Free LSM resources associated with @ctx. 5311 */ 5312 void security_xfrm_policy_free(struct xfrm_sec_ctx *ctx) 5313 { 5314 call_void_hook(xfrm_policy_free_security, ctx); 5315 } 5316 EXPORT_SYMBOL(security_xfrm_policy_free); 5317 5318 /** 5319 * security_xfrm_policy_delete() - Check if deleting a xfrm policy is allowed 5320 * @ctx: xfrm security context 5321 * 5322 * Authorize deletion of a SPD entry. 5323 * 5324 * Return: Returns 0 if permission is granted. 5325 */ 5326 int security_xfrm_policy_delete(struct xfrm_sec_ctx *ctx) 5327 { 5328 return call_int_hook(xfrm_policy_delete_security, ctx); 5329 } 5330 5331 /** 5332 * security_xfrm_state_alloc() - Allocate a xfrm state LSM blob 5333 * @x: xfrm state being added to the SAD 5334 * @sec_ctx: security label provided by userspace 5335 * 5336 * Allocate a security structure to the @x->security field; the security field 5337 * is initialized to NULL when the xfrm_state is allocated. Set the context to 5338 * correspond to @sec_ctx. 5339 * 5340 * Return: Return 0 if operation was successful. 5341 */ 5342 int security_xfrm_state_alloc(struct xfrm_state *x, 5343 struct xfrm_user_sec_ctx *sec_ctx) 5344 { 5345 return call_int_hook(xfrm_state_alloc, x, sec_ctx); 5346 } 5347 EXPORT_SYMBOL(security_xfrm_state_alloc); 5348 5349 /** 5350 * security_xfrm_state_alloc_acquire() - Allocate a xfrm state LSM blob 5351 * @x: xfrm state being added to the SAD 5352 * @polsec: associated policy's security context 5353 * @secid: secid from the flow 5354 * 5355 * Allocate a security structure to the x->security field; the security field 5356 * is initialized to NULL when the xfrm_state is allocated. Set the context to 5357 * correspond to secid. 5358 * 5359 * Return: Returns 0 if operation was successful. 5360 */ 5361 int security_xfrm_state_alloc_acquire(struct xfrm_state *x, 5362 struct xfrm_sec_ctx *polsec, u32 secid) 5363 { 5364 return call_int_hook(xfrm_state_alloc_acquire, x, polsec, secid); 5365 } 5366 5367 /** 5368 * security_xfrm_state_delete() - Check if deleting a xfrm state is allowed 5369 * @x: xfrm state 5370 * 5371 * Authorize deletion of x->security. 5372 * 5373 * Return: Returns 0 if permission is granted. 5374 */ 5375 int security_xfrm_state_delete(struct xfrm_state *x) 5376 { 5377 return call_int_hook(xfrm_state_delete_security, x); 5378 } 5379 EXPORT_SYMBOL(security_xfrm_state_delete); 5380 5381 /** 5382 * security_xfrm_state_free() - Free a xfrm state 5383 * @x: xfrm state 5384 * 5385 * Deallocate x->security. 5386 */ 5387 void security_xfrm_state_free(struct xfrm_state *x) 5388 { 5389 call_void_hook(xfrm_state_free_security, x); 5390 } 5391 5392 /** 5393 * security_xfrm_policy_lookup() - Check if using a xfrm policy is allowed 5394 * @ctx: target xfrm security context 5395 * @fl_secid: flow secid used to authorize access 5396 * 5397 * Check permission when a flow selects a xfrm_policy for processing XFRMs on a 5398 * packet. The hook is called when selecting either a per-socket policy or a 5399 * generic xfrm policy. 5400 * 5401 * Return: Return 0 if permission is granted, -ESRCH otherwise, or -errno on 5402 * other errors. 5403 */ 5404 int security_xfrm_policy_lookup(struct xfrm_sec_ctx *ctx, u32 fl_secid) 5405 { 5406 return call_int_hook(xfrm_policy_lookup, ctx, fl_secid); 5407 } 5408 5409 /** 5410 * security_xfrm_state_pol_flow_match() - Check for a xfrm match 5411 * @x: xfrm state to match 5412 * @xp: xfrm policy to check for a match 5413 * @flic: flow to check for a match. 5414 * 5415 * Check @xp and @flic for a match with @x. 5416 * 5417 * Return: Returns 1 if there is a match. 5418 */ 5419 int security_xfrm_state_pol_flow_match(struct xfrm_state *x, 5420 struct xfrm_policy *xp, 5421 const struct flowi_common *flic) 5422 { 5423 struct lsm_static_call *scall; 5424 int rc = LSM_RET_DEFAULT(xfrm_state_pol_flow_match); 5425 5426 /* 5427 * Since this function is expected to return 0 or 1, the judgment 5428 * becomes difficult if multiple LSMs supply this call. Fortunately, 5429 * we can use the first LSM's judgment because currently only SELinux 5430 * supplies this call. 5431 * 5432 * For speed optimization, we explicitly break the loop rather than 5433 * using the macro 5434 */ 5435 lsm_for_each_hook(scall, xfrm_state_pol_flow_match) { 5436 rc = scall->hl->hook.xfrm_state_pol_flow_match(x, xp, flic); 5437 break; 5438 } 5439 return rc; 5440 } 5441 5442 /** 5443 * security_xfrm_decode_session() - Determine the xfrm secid for a packet 5444 * @skb: xfrm packet 5445 * @secid: secid 5446 * 5447 * Decode the packet in @skb and return the security label in @secid. 5448 * 5449 * Return: Return 0 if all xfrms used have the same secid. 5450 */ 5451 int security_xfrm_decode_session(struct sk_buff *skb, u32 *secid) 5452 { 5453 return call_int_hook(xfrm_decode_session, skb, secid, 1); 5454 } 5455 5456 void security_skb_classify_flow(struct sk_buff *skb, struct flowi_common *flic) 5457 { 5458 int rc = call_int_hook(xfrm_decode_session, skb, &flic->flowic_secid, 5459 0); 5460 5461 BUG_ON(rc); 5462 } 5463 EXPORT_SYMBOL(security_skb_classify_flow); 5464 #endif /* CONFIG_SECURITY_NETWORK_XFRM */ 5465 5466 #ifdef CONFIG_KEYS 5467 /** 5468 * security_key_alloc() - Allocate and initialize a kernel key LSM blob 5469 * @key: key 5470 * @cred: credentials 5471 * @flags: allocation flags 5472 * 5473 * Permit allocation of a key and assign security data. Note that key does not 5474 * have a serial number assigned at this point. 5475 * 5476 * Return: Return 0 if permission is granted, -ve error otherwise. 5477 */ 5478 int security_key_alloc(struct key *key, const struct cred *cred, 5479 unsigned long flags) 5480 { 5481 int rc = lsm_key_alloc(key); 5482 5483 if (unlikely(rc)) 5484 return rc; 5485 rc = call_int_hook(key_alloc, key, cred, flags); 5486 if (unlikely(rc)) 5487 security_key_free(key); 5488 return rc; 5489 } 5490 5491 /** 5492 * security_key_free() - Free a kernel key LSM blob 5493 * @key: key 5494 * 5495 * Notification of destruction; free security data. 5496 */ 5497 void security_key_free(struct key *key) 5498 { 5499 kfree(key->security); 5500 key->security = NULL; 5501 } 5502 5503 /** 5504 * security_key_permission() - Check if a kernel key operation is allowed 5505 * @key_ref: key reference 5506 * @cred: credentials of actor requesting access 5507 * @need_perm: requested permissions 5508 * 5509 * See whether a specific operational right is granted to a process on a key. 5510 * 5511 * Return: Return 0 if permission is granted, -ve error otherwise. 5512 */ 5513 int security_key_permission(key_ref_t key_ref, const struct cred *cred, 5514 enum key_need_perm need_perm) 5515 { 5516 return call_int_hook(key_permission, key_ref, cred, need_perm); 5517 } 5518 5519 /** 5520 * security_key_getsecurity() - Get the key's security label 5521 * @key: key 5522 * @buffer: security label buffer 5523 * 5524 * Get a textual representation of the security context attached to a key for 5525 * the purposes of honouring KEYCTL_GETSECURITY. This function allocates the 5526 * storage for the NUL-terminated string and the caller should free it. 5527 * 5528 * Return: Returns the length of @buffer (including terminating NUL) or -ve if 5529 * an error occurs. May also return 0 (and a NULL buffer pointer) if 5530 * there is no security label assigned to the key. 5531 */ 5532 int security_key_getsecurity(struct key *key, char **buffer) 5533 { 5534 *buffer = NULL; 5535 return call_int_hook(key_getsecurity, key, buffer); 5536 } 5537 5538 /** 5539 * security_key_post_create_or_update() - Notification of key create or update 5540 * @keyring: keyring to which the key is linked to 5541 * @key: created or updated key 5542 * @payload: data used to instantiate or update the key 5543 * @payload_len: length of payload 5544 * @flags: key flags 5545 * @create: flag indicating whether the key was created or updated 5546 * 5547 * Notify the caller of a key creation or update. 5548 */ 5549 void security_key_post_create_or_update(struct key *keyring, struct key *key, 5550 const void *payload, size_t payload_len, 5551 unsigned long flags, bool create) 5552 { 5553 call_void_hook(key_post_create_or_update, keyring, key, payload, 5554 payload_len, flags, create); 5555 } 5556 #endif /* CONFIG_KEYS */ 5557 5558 #ifdef CONFIG_AUDIT 5559 /** 5560 * security_audit_rule_init() - Allocate and init an LSM audit rule struct 5561 * @field: audit action 5562 * @op: rule operator 5563 * @rulestr: rule context 5564 * @lsmrule: receive buffer for audit rule struct 5565 * @gfp: GFP flag used for kmalloc 5566 * 5567 * Allocate and initialize an LSM audit rule structure. 5568 * 5569 * Return: Return 0 if @lsmrule has been successfully set, -EINVAL in case of 5570 * an invalid rule. 5571 */ 5572 int security_audit_rule_init(u32 field, u32 op, char *rulestr, void **lsmrule, 5573 gfp_t gfp) 5574 { 5575 return call_int_hook(audit_rule_init, field, op, rulestr, lsmrule, gfp); 5576 } 5577 5578 /** 5579 * security_audit_rule_known() - Check if an audit rule contains LSM fields 5580 * @krule: audit rule 5581 * 5582 * Specifies whether given @krule contains any fields related to the current 5583 * LSM. 5584 * 5585 * Return: Returns 1 in case of relation found, 0 otherwise. 5586 */ 5587 int security_audit_rule_known(struct audit_krule *krule) 5588 { 5589 return call_int_hook(audit_rule_known, krule); 5590 } 5591 5592 /** 5593 * security_audit_rule_free() - Free an LSM audit rule struct 5594 * @lsmrule: audit rule struct 5595 * 5596 * Deallocate the LSM audit rule structure previously allocated by 5597 * audit_rule_init(). 5598 */ 5599 void security_audit_rule_free(void *lsmrule) 5600 { 5601 call_void_hook(audit_rule_free, lsmrule); 5602 } 5603 5604 /** 5605 * security_audit_rule_match() - Check if a label matches an audit rule 5606 * @prop: security label 5607 * @field: LSM audit field 5608 * @op: matching operator 5609 * @lsmrule: audit rule 5610 * 5611 * Determine if given @secid matches a rule previously approved by 5612 * security_audit_rule_known(). 5613 * 5614 * Return: Returns 1 if secid matches the rule, 0 if it does not, -ERRNO on 5615 * failure. 5616 */ 5617 int security_audit_rule_match(struct lsm_prop *prop, u32 field, u32 op, 5618 void *lsmrule) 5619 { 5620 return call_int_hook(audit_rule_match, prop, field, op, lsmrule); 5621 } 5622 #endif /* CONFIG_AUDIT */ 5623 5624 #ifdef CONFIG_BPF_SYSCALL 5625 /** 5626 * security_bpf() - Check if the bpf syscall operation is allowed 5627 * @cmd: command 5628 * @attr: bpf attribute 5629 * @size: size 5630 * 5631 * Do a initial check for all bpf syscalls after the attribute is copied into 5632 * the kernel. The actual security module can implement their own rules to 5633 * check the specific cmd they need. 5634 * 5635 * Return: Returns 0 if permission is granted. 5636 */ 5637 int security_bpf(int cmd, union bpf_attr *attr, unsigned int size) 5638 { 5639 return call_int_hook(bpf, cmd, attr, size); 5640 } 5641 5642 /** 5643 * security_bpf_map() - Check if access to a bpf map is allowed 5644 * @map: bpf map 5645 * @fmode: mode 5646 * 5647 * Do a check when the kernel generates and returns a file descriptor for eBPF 5648 * maps. 5649 * 5650 * Return: Returns 0 if permission is granted. 5651 */ 5652 int security_bpf_map(struct bpf_map *map, fmode_t fmode) 5653 { 5654 return call_int_hook(bpf_map, map, fmode); 5655 } 5656 5657 /** 5658 * security_bpf_prog() - Check if access to a bpf program is allowed 5659 * @prog: bpf program 5660 * 5661 * Do a check when the kernel generates and returns a file descriptor for eBPF 5662 * programs. 5663 * 5664 * Return: Returns 0 if permission is granted. 5665 */ 5666 int security_bpf_prog(struct bpf_prog *prog) 5667 { 5668 return call_int_hook(bpf_prog, prog); 5669 } 5670 5671 /** 5672 * security_bpf_map_create() - Check if BPF map creation is allowed 5673 * @map: BPF map object 5674 * @attr: BPF syscall attributes used to create BPF map 5675 * @token: BPF token used to grant user access 5676 * 5677 * Do a check when the kernel creates a new BPF map. This is also the 5678 * point where LSM blob is allocated for LSMs that need them. 5679 * 5680 * Return: Returns 0 on success, error on failure. 5681 */ 5682 int security_bpf_map_create(struct bpf_map *map, union bpf_attr *attr, 5683 struct bpf_token *token) 5684 { 5685 return call_int_hook(bpf_map_create, map, attr, token); 5686 } 5687 5688 /** 5689 * security_bpf_prog_load() - Check if loading of BPF program is allowed 5690 * @prog: BPF program object 5691 * @attr: BPF syscall attributes used to create BPF program 5692 * @token: BPF token used to grant user access to BPF subsystem 5693 * 5694 * Perform an access control check when the kernel loads a BPF program and 5695 * allocates associated BPF program object. This hook is also responsible for 5696 * allocating any required LSM state for the BPF program. 5697 * 5698 * Return: Returns 0 on success, error on failure. 5699 */ 5700 int security_bpf_prog_load(struct bpf_prog *prog, union bpf_attr *attr, 5701 struct bpf_token *token) 5702 { 5703 return call_int_hook(bpf_prog_load, prog, attr, token); 5704 } 5705 5706 /** 5707 * security_bpf_token_create() - Check if creating of BPF token is allowed 5708 * @token: BPF token object 5709 * @attr: BPF syscall attributes used to create BPF token 5710 * @path: path pointing to BPF FS mount point from which BPF token is created 5711 * 5712 * Do a check when the kernel instantiates a new BPF token object from BPF FS 5713 * instance. This is also the point where LSM blob can be allocated for LSMs. 5714 * 5715 * Return: Returns 0 on success, error on failure. 5716 */ 5717 int security_bpf_token_create(struct bpf_token *token, union bpf_attr *attr, 5718 const struct path *path) 5719 { 5720 return call_int_hook(bpf_token_create, token, attr, path); 5721 } 5722 5723 /** 5724 * security_bpf_token_cmd() - Check if BPF token is allowed to delegate 5725 * requested BPF syscall command 5726 * @token: BPF token object 5727 * @cmd: BPF syscall command requested to be delegated by BPF token 5728 * 5729 * Do a check when the kernel decides whether provided BPF token should allow 5730 * delegation of requested BPF syscall command. 5731 * 5732 * Return: Returns 0 on success, error on failure. 5733 */ 5734 int security_bpf_token_cmd(const struct bpf_token *token, enum bpf_cmd cmd) 5735 { 5736 return call_int_hook(bpf_token_cmd, token, cmd); 5737 } 5738 5739 /** 5740 * security_bpf_token_capable() - Check if BPF token is allowed to delegate 5741 * requested BPF-related capability 5742 * @token: BPF token object 5743 * @cap: capabilities requested to be delegated by BPF token 5744 * 5745 * Do a check when the kernel decides whether provided BPF token should allow 5746 * delegation of requested BPF-related capabilities. 5747 * 5748 * Return: Returns 0 on success, error on failure. 5749 */ 5750 int security_bpf_token_capable(const struct bpf_token *token, int cap) 5751 { 5752 return call_int_hook(bpf_token_capable, token, cap); 5753 } 5754 5755 /** 5756 * security_bpf_map_free() - Free a bpf map's LSM blob 5757 * @map: bpf map 5758 * 5759 * Clean up the security information stored inside bpf map. 5760 */ 5761 void security_bpf_map_free(struct bpf_map *map) 5762 { 5763 call_void_hook(bpf_map_free, map); 5764 } 5765 5766 /** 5767 * security_bpf_prog_free() - Free a BPF program's LSM blob 5768 * @prog: BPF program struct 5769 * 5770 * Clean up the security information stored inside BPF program. 5771 */ 5772 void security_bpf_prog_free(struct bpf_prog *prog) 5773 { 5774 call_void_hook(bpf_prog_free, prog); 5775 } 5776 5777 /** 5778 * security_bpf_token_free() - Free a BPF token's LSM blob 5779 * @token: BPF token struct 5780 * 5781 * Clean up the security information stored inside BPF token. 5782 */ 5783 void security_bpf_token_free(struct bpf_token *token) 5784 { 5785 call_void_hook(bpf_token_free, token); 5786 } 5787 #endif /* CONFIG_BPF_SYSCALL */ 5788 5789 /** 5790 * security_locked_down() - Check if a kernel feature is allowed 5791 * @what: requested kernel feature 5792 * 5793 * Determine whether a kernel feature that potentially enables arbitrary code 5794 * execution in kernel space should be permitted. 5795 * 5796 * Return: Returns 0 if permission is granted. 5797 */ 5798 int security_locked_down(enum lockdown_reason what) 5799 { 5800 return call_int_hook(locked_down, what); 5801 } 5802 EXPORT_SYMBOL(security_locked_down); 5803 5804 /** 5805 * security_bdev_alloc() - Allocate a block device LSM blob 5806 * @bdev: block device 5807 * 5808 * Allocate and attach a security structure to @bdev->bd_security. The 5809 * security field is initialized to NULL when the bdev structure is 5810 * allocated. 5811 * 5812 * Return: Return 0 if operation was successful. 5813 */ 5814 int security_bdev_alloc(struct block_device *bdev) 5815 { 5816 int rc = 0; 5817 5818 rc = lsm_bdev_alloc(bdev); 5819 if (unlikely(rc)) 5820 return rc; 5821 5822 rc = call_int_hook(bdev_alloc_security, bdev); 5823 if (unlikely(rc)) 5824 security_bdev_free(bdev); 5825 5826 return rc; 5827 } 5828 EXPORT_SYMBOL(security_bdev_alloc); 5829 5830 /** 5831 * security_bdev_free() - Free a block device's LSM blob 5832 * @bdev: block device 5833 * 5834 * Deallocate the bdev security structure and set @bdev->bd_security to NULL. 5835 */ 5836 void security_bdev_free(struct block_device *bdev) 5837 { 5838 if (!bdev->bd_security) 5839 return; 5840 5841 call_void_hook(bdev_free_security, bdev); 5842 5843 kfree(bdev->bd_security); 5844 bdev->bd_security = NULL; 5845 } 5846 EXPORT_SYMBOL(security_bdev_free); 5847 5848 /** 5849 * security_bdev_setintegrity() - Set the device's integrity data 5850 * @bdev: block device 5851 * @type: type of integrity, e.g. hash digest, signature, etc 5852 * @value: the integrity value 5853 * @size: size of the integrity value 5854 * 5855 * Register a verified integrity measurement of a bdev with LSMs. 5856 * LSMs should free the previously saved data if @value is NULL. 5857 * Please note that the new hook should be invoked every time the security 5858 * information is updated to keep these data current. For example, in dm-verity, 5859 * if the mapping table is reloaded and configured to use a different dm-verity 5860 * target with a new roothash and signing information, the previously stored 5861 * data in the LSM blob will become obsolete. It is crucial to re-invoke the 5862 * hook to refresh these data and ensure they are up to date. This necessity 5863 * arises from the design of device-mapper, where a device-mapper device is 5864 * first created, and then targets are subsequently loaded into it. These 5865 * targets can be modified multiple times during the device's lifetime. 5866 * Therefore, while the LSM blob is allocated during the creation of the block 5867 * device, its actual contents are not initialized at this stage and can change 5868 * substantially over time. This includes alterations from data that the LSMs 5869 * 'trusts' to those they do not, making it essential to handle these changes 5870 * correctly. Failure to address this dynamic aspect could potentially allow 5871 * for bypassing LSM checks. 5872 * 5873 * Return: Returns 0 on success, negative values on failure. 5874 */ 5875 int security_bdev_setintegrity(struct block_device *bdev, 5876 enum lsm_integrity_type type, const void *value, 5877 size_t size) 5878 { 5879 return call_int_hook(bdev_setintegrity, bdev, type, value, size); 5880 } 5881 EXPORT_SYMBOL(security_bdev_setintegrity); 5882 5883 #ifdef CONFIG_PERF_EVENTS 5884 /** 5885 * security_perf_event_open() - Check if a perf event open is allowed 5886 * @attr: perf event attribute 5887 * @type: type of event 5888 * 5889 * Check whether the @type of perf_event_open syscall is allowed. 5890 * 5891 * Return: Returns 0 if permission is granted. 5892 */ 5893 int security_perf_event_open(struct perf_event_attr *attr, int type) 5894 { 5895 return call_int_hook(perf_event_open, attr, type); 5896 } 5897 5898 /** 5899 * security_perf_event_alloc() - Allocate a perf event LSM blob 5900 * @event: perf event 5901 * 5902 * Allocate and save perf_event security info. 5903 * 5904 * Return: Returns 0 on success, error on failure. 5905 */ 5906 int security_perf_event_alloc(struct perf_event *event) 5907 { 5908 int rc; 5909 5910 rc = lsm_blob_alloc(&event->security, blob_sizes.lbs_perf_event, 5911 GFP_KERNEL); 5912 if (rc) 5913 return rc; 5914 5915 rc = call_int_hook(perf_event_alloc, event); 5916 if (rc) { 5917 kfree(event->security); 5918 event->security = NULL; 5919 } 5920 return rc; 5921 } 5922 5923 /** 5924 * security_perf_event_free() - Free a perf event LSM blob 5925 * @event: perf event 5926 * 5927 * Release (free) perf_event security info. 5928 */ 5929 void security_perf_event_free(struct perf_event *event) 5930 { 5931 kfree(event->security); 5932 event->security = NULL; 5933 } 5934 5935 /** 5936 * security_perf_event_read() - Check if reading a perf event label is allowed 5937 * @event: perf event 5938 * 5939 * Read perf_event security info if allowed. 5940 * 5941 * Return: Returns 0 if permission is granted. 5942 */ 5943 int security_perf_event_read(struct perf_event *event) 5944 { 5945 return call_int_hook(perf_event_read, event); 5946 } 5947 5948 /** 5949 * security_perf_event_write() - Check if writing a perf event label is allowed 5950 * @event: perf event 5951 * 5952 * Write perf_event security info if allowed. 5953 * 5954 * Return: Returns 0 if permission is granted. 5955 */ 5956 int security_perf_event_write(struct perf_event *event) 5957 { 5958 return call_int_hook(perf_event_write, event); 5959 } 5960 #endif /* CONFIG_PERF_EVENTS */ 5961 5962 #ifdef CONFIG_IO_URING 5963 /** 5964 * security_uring_override_creds() - Check if overriding creds is allowed 5965 * @new: new credentials 5966 * 5967 * Check if the current task, executing an io_uring operation, is allowed to 5968 * override it's credentials with @new. 5969 * 5970 * Return: Returns 0 if permission is granted. 5971 */ 5972 int security_uring_override_creds(const struct cred *new) 5973 { 5974 return call_int_hook(uring_override_creds, new); 5975 } 5976 5977 /** 5978 * security_uring_sqpoll() - Check if IORING_SETUP_SQPOLL is allowed 5979 * 5980 * Check whether the current task is allowed to spawn a io_uring polling thread 5981 * (IORING_SETUP_SQPOLL). 5982 * 5983 * Return: Returns 0 if permission is granted. 5984 */ 5985 int security_uring_sqpoll(void) 5986 { 5987 return call_int_hook(uring_sqpoll); 5988 } 5989 5990 /** 5991 * security_uring_cmd() - Check if a io_uring passthrough command is allowed 5992 * @ioucmd: command 5993 * 5994 * Check whether the file_operations uring_cmd is allowed to run. 5995 * 5996 * Return: Returns 0 if permission is granted. 5997 */ 5998 int security_uring_cmd(struct io_uring_cmd *ioucmd) 5999 { 6000 return call_int_hook(uring_cmd, ioucmd); 6001 } 6002 #endif /* CONFIG_IO_URING */ 6003 6004 /** 6005 * security_initramfs_populated() - Notify LSMs that initramfs has been loaded 6006 * 6007 * Tells the LSMs the initramfs has been unpacked into the rootfs. 6008 */ 6009 void security_initramfs_populated(void) 6010 { 6011 call_void_hook(initramfs_populated); 6012 } 6013