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