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