xref: /linux/security/security.c (revision 2d7f3d1a5866705be2393150e1ffdf67030ab88d)
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 <linux/overflow.h>
33 #include <net/flow.h>
34 
35 /* How many LSMs were built into the kernel? */
36 #define LSM_COUNT (__end_lsm_info - __start_lsm_info)
37 
38 /*
39  * How many LSMs are built into the kernel as determined at
40  * build time. Used to determine fixed array sizes.
41  * The capability module is accounted for by CONFIG_SECURITY
42  */
43 #define LSM_CONFIG_COUNT ( \
44 	(IS_ENABLED(CONFIG_SECURITY) ? 1 : 0) + \
45 	(IS_ENABLED(CONFIG_SECURITY_SELINUX) ? 1 : 0) + \
46 	(IS_ENABLED(CONFIG_SECURITY_SMACK) ? 1 : 0) + \
47 	(IS_ENABLED(CONFIG_SECURITY_TOMOYO) ? 1 : 0) + \
48 	(IS_ENABLED(CONFIG_SECURITY_APPARMOR) ? 1 : 0) + \
49 	(IS_ENABLED(CONFIG_SECURITY_YAMA) ? 1 : 0) + \
50 	(IS_ENABLED(CONFIG_SECURITY_LOADPIN) ? 1 : 0) + \
51 	(IS_ENABLED(CONFIG_SECURITY_SAFESETID) ? 1 : 0) + \
52 	(IS_ENABLED(CONFIG_SECURITY_LOCKDOWN_LSM) ? 1 : 0) + \
53 	(IS_ENABLED(CONFIG_BPF_LSM) ? 1 : 0) + \
54 	(IS_ENABLED(CONFIG_SECURITY_LANDLOCK) ? 1 : 0))
55 
56 /*
57  * These are descriptions of the reasons that can be passed to the
58  * security_locked_down() LSM hook. Placing this array here allows
59  * all security modules to use the same descriptions for auditing
60  * purposes.
61  */
62 const char *const lockdown_reasons[LOCKDOWN_CONFIDENTIALITY_MAX + 1] = {
63 	[LOCKDOWN_NONE] = "none",
64 	[LOCKDOWN_MODULE_SIGNATURE] = "unsigned module loading",
65 	[LOCKDOWN_DEV_MEM] = "/dev/mem,kmem,port",
66 	[LOCKDOWN_EFI_TEST] = "/dev/efi_test access",
67 	[LOCKDOWN_KEXEC] = "kexec of unsigned images",
68 	[LOCKDOWN_HIBERNATION] = "hibernation",
69 	[LOCKDOWN_PCI_ACCESS] = "direct PCI access",
70 	[LOCKDOWN_IOPORT] = "raw io port access",
71 	[LOCKDOWN_MSR] = "raw MSR access",
72 	[LOCKDOWN_ACPI_TABLES] = "modifying ACPI tables",
73 	[LOCKDOWN_DEVICE_TREE] = "modifying device tree contents",
74 	[LOCKDOWN_PCMCIA_CIS] = "direct PCMCIA CIS storage",
75 	[LOCKDOWN_TIOCSSERIAL] = "reconfiguration of serial port IO",
76 	[LOCKDOWN_MODULE_PARAMETERS] = "unsafe module parameters",
77 	[LOCKDOWN_MMIOTRACE] = "unsafe mmio",
78 	[LOCKDOWN_DEBUGFS] = "debugfs access",
79 	[LOCKDOWN_XMON_WR] = "xmon write access",
80 	[LOCKDOWN_BPF_WRITE_USER] = "use of bpf to write user RAM",
81 	[LOCKDOWN_DBG_WRITE_KERNEL] = "use of kgdb/kdb to write kernel RAM",
82 	[LOCKDOWN_RTAS_ERROR_INJECTION] = "RTAS error injection",
83 	[LOCKDOWN_INTEGRITY_MAX] = "integrity",
84 	[LOCKDOWN_KCORE] = "/proc/kcore access",
85 	[LOCKDOWN_KPROBES] = "use of kprobes",
86 	[LOCKDOWN_BPF_READ_KERNEL] = "use of bpf to read kernel RAM",
87 	[LOCKDOWN_DBG_READ_KERNEL] = "use of kgdb/kdb to read kernel RAM",
88 	[LOCKDOWN_PERF] = "unsafe use of perf",
89 	[LOCKDOWN_TRACEFS] = "use of tracefs",
90 	[LOCKDOWN_XMON_RW] = "xmon read and write access",
91 	[LOCKDOWN_XFRM_SECRET] = "xfrm SA secret",
92 	[LOCKDOWN_CONFIDENTIALITY_MAX] = "confidentiality",
93 };
94 
95 struct security_hook_heads security_hook_heads __ro_after_init;
96 static BLOCKING_NOTIFIER_HEAD(blocking_lsm_notifier_chain);
97 
98 static struct kmem_cache *lsm_file_cache;
99 static struct kmem_cache *lsm_inode_cache;
100 
101 char *lsm_names;
102 static struct lsm_blob_sizes blob_sizes __ro_after_init;
103 
104 /* Boot-time LSM user choice */
105 static __initdata const char *chosen_lsm_order;
106 static __initdata const char *chosen_major_lsm;
107 
108 static __initconst const char *const builtin_lsm_order = CONFIG_LSM;
109 
110 /* Ordered list of LSMs to initialize. */
111 static __initdata struct lsm_info **ordered_lsms;
112 static __initdata struct lsm_info *exclusive;
113 
114 static __initdata bool debug;
115 #define init_debug(...)						\
116 	do {							\
117 		if (debug)					\
118 			pr_info(__VA_ARGS__);			\
119 	} while (0)
120 
121 static bool __init is_enabled(struct lsm_info *lsm)
122 {
123 	if (!lsm->enabled)
124 		return false;
125 
126 	return *lsm->enabled;
127 }
128 
129 /* Mark an LSM's enabled flag. */
130 static int lsm_enabled_true __initdata = 1;
131 static int lsm_enabled_false __initdata = 0;
132 static void __init set_enabled(struct lsm_info *lsm, bool enabled)
133 {
134 	/*
135 	 * When an LSM hasn't configured an enable variable, we can use
136 	 * a hard-coded location for storing the default enabled state.
137 	 */
138 	if (!lsm->enabled) {
139 		if (enabled)
140 			lsm->enabled = &lsm_enabled_true;
141 		else
142 			lsm->enabled = &lsm_enabled_false;
143 	} else if (lsm->enabled == &lsm_enabled_true) {
144 		if (!enabled)
145 			lsm->enabled = &lsm_enabled_false;
146 	} else if (lsm->enabled == &lsm_enabled_false) {
147 		if (enabled)
148 			lsm->enabled = &lsm_enabled_true;
149 	} else {
150 		*lsm->enabled = enabled;
151 	}
152 }
153 
154 /* Is an LSM already listed in the ordered LSMs list? */
155 static bool __init exists_ordered_lsm(struct lsm_info *lsm)
156 {
157 	struct lsm_info **check;
158 
159 	for (check = ordered_lsms; *check; check++)
160 		if (*check == lsm)
161 			return true;
162 
163 	return false;
164 }
165 
166 /* Append an LSM to the list of ordered LSMs to initialize. */
167 static int last_lsm __initdata;
168 static void __init append_ordered_lsm(struct lsm_info *lsm, const char *from)
169 {
170 	/* Ignore duplicate selections. */
171 	if (exists_ordered_lsm(lsm))
172 		return;
173 
174 	if (WARN(last_lsm == LSM_COUNT, "%s: out of LSM slots!?\n", from))
175 		return;
176 
177 	/* Enable this LSM, if it is not already set. */
178 	if (!lsm->enabled)
179 		lsm->enabled = &lsm_enabled_true;
180 	ordered_lsms[last_lsm++] = lsm;
181 
182 	init_debug("%s ordered: %s (%s)\n", from, lsm->name,
183 		   is_enabled(lsm) ? "enabled" : "disabled");
184 }
185 
186 /* Is an LSM allowed to be initialized? */
187 static bool __init lsm_allowed(struct lsm_info *lsm)
188 {
189 	/* Skip if the LSM is disabled. */
190 	if (!is_enabled(lsm))
191 		return false;
192 
193 	/* Not allowed if another exclusive LSM already initialized. */
194 	if ((lsm->flags & LSM_FLAG_EXCLUSIVE) && exclusive) {
195 		init_debug("exclusive disabled: %s\n", lsm->name);
196 		return false;
197 	}
198 
199 	return true;
200 }
201 
202 static void __init lsm_set_blob_size(int *need, int *lbs)
203 {
204 	int offset;
205 
206 	if (*need <= 0)
207 		return;
208 
209 	offset = ALIGN(*lbs, sizeof(void *));
210 	*lbs = offset + *need;
211 	*need = offset;
212 }
213 
214 static void __init lsm_set_blob_sizes(struct lsm_blob_sizes *needed)
215 {
216 	if (!needed)
217 		return;
218 
219 	lsm_set_blob_size(&needed->lbs_cred, &blob_sizes.lbs_cred);
220 	lsm_set_blob_size(&needed->lbs_file, &blob_sizes.lbs_file);
221 	/*
222 	 * The inode blob gets an rcu_head in addition to
223 	 * what the modules might need.
224 	 */
225 	if (needed->lbs_inode && blob_sizes.lbs_inode == 0)
226 		blob_sizes.lbs_inode = sizeof(struct rcu_head);
227 	lsm_set_blob_size(&needed->lbs_inode, &blob_sizes.lbs_inode);
228 	lsm_set_blob_size(&needed->lbs_ipc, &blob_sizes.lbs_ipc);
229 	lsm_set_blob_size(&needed->lbs_msg_msg, &blob_sizes.lbs_msg_msg);
230 	lsm_set_blob_size(&needed->lbs_superblock, &blob_sizes.lbs_superblock);
231 	lsm_set_blob_size(&needed->lbs_task, &blob_sizes.lbs_task);
232 	lsm_set_blob_size(&needed->lbs_xattr_count,
233 			  &blob_sizes.lbs_xattr_count);
234 }
235 
236 /* Prepare LSM for initialization. */
237 static void __init prepare_lsm(struct lsm_info *lsm)
238 {
239 	int enabled = lsm_allowed(lsm);
240 
241 	/* Record enablement (to handle any following exclusive LSMs). */
242 	set_enabled(lsm, enabled);
243 
244 	/* If enabled, do pre-initialization work. */
245 	if (enabled) {
246 		if ((lsm->flags & LSM_FLAG_EXCLUSIVE) && !exclusive) {
247 			exclusive = lsm;
248 			init_debug("exclusive chosen:   %s\n", lsm->name);
249 		}
250 
251 		lsm_set_blob_sizes(lsm->blobs);
252 	}
253 }
254 
255 /* Initialize a given LSM, if it is enabled. */
256 static void __init initialize_lsm(struct lsm_info *lsm)
257 {
258 	if (is_enabled(lsm)) {
259 		int ret;
260 
261 		init_debug("initializing %s\n", lsm->name);
262 		ret = lsm->init();
263 		WARN(ret, "%s failed to initialize: %d\n", lsm->name, ret);
264 	}
265 }
266 
267 /*
268  * Current index to use while initializing the lsm id list.
269  */
270 u32 lsm_active_cnt __ro_after_init;
271 const struct lsm_id *lsm_idlist[LSM_CONFIG_COUNT];
272 
273 /* Populate ordered LSMs list from comma-separated LSM name list. */
274 static void __init ordered_lsm_parse(const char *order, const char *origin)
275 {
276 	struct lsm_info *lsm;
277 	char *sep, *name, *next;
278 
279 	/* LSM_ORDER_FIRST is always first. */
280 	for (lsm = __start_lsm_info; lsm < __end_lsm_info; lsm++) {
281 		if (lsm->order == LSM_ORDER_FIRST)
282 			append_ordered_lsm(lsm, "  first");
283 	}
284 
285 	/* Process "security=", if given. */
286 	if (chosen_major_lsm) {
287 		struct lsm_info *major;
288 
289 		/*
290 		 * To match the original "security=" behavior, this
291 		 * explicitly does NOT fallback to another Legacy Major
292 		 * if the selected one was separately disabled: disable
293 		 * all non-matching Legacy Major LSMs.
294 		 */
295 		for (major = __start_lsm_info; major < __end_lsm_info;
296 		     major++) {
297 			if ((major->flags & LSM_FLAG_LEGACY_MAJOR) &&
298 			    strcmp(major->name, chosen_major_lsm) != 0) {
299 				set_enabled(major, false);
300 				init_debug("security=%s disabled: %s (only one legacy major LSM)\n",
301 					   chosen_major_lsm, major->name);
302 			}
303 		}
304 	}
305 
306 	sep = kstrdup(order, GFP_KERNEL);
307 	next = sep;
308 	/* Walk the list, looking for matching LSMs. */
309 	while ((name = strsep(&next, ",")) != NULL) {
310 		bool found = false;
311 
312 		for (lsm = __start_lsm_info; lsm < __end_lsm_info; lsm++) {
313 			if (strcmp(lsm->name, name) == 0) {
314 				if (lsm->order == LSM_ORDER_MUTABLE)
315 					append_ordered_lsm(lsm, origin);
316 				found = true;
317 			}
318 		}
319 
320 		if (!found)
321 			init_debug("%s ignored: %s (not built into kernel)\n",
322 				   origin, name);
323 	}
324 
325 	/* Process "security=", if given. */
326 	if (chosen_major_lsm) {
327 		for (lsm = __start_lsm_info; lsm < __end_lsm_info; lsm++) {
328 			if (exists_ordered_lsm(lsm))
329 				continue;
330 			if (strcmp(lsm->name, chosen_major_lsm) == 0)
331 				append_ordered_lsm(lsm, "security=");
332 		}
333 	}
334 
335 	/* LSM_ORDER_LAST is always last. */
336 	for (lsm = __start_lsm_info; lsm < __end_lsm_info; lsm++) {
337 		if (lsm->order == LSM_ORDER_LAST)
338 			append_ordered_lsm(lsm, "   last");
339 	}
340 
341 	/* Disable all LSMs not in the ordered list. */
342 	for (lsm = __start_lsm_info; lsm < __end_lsm_info; lsm++) {
343 		if (exists_ordered_lsm(lsm))
344 			continue;
345 		set_enabled(lsm, false);
346 		init_debug("%s skipped: %s (not in requested order)\n",
347 			   origin, lsm->name);
348 	}
349 
350 	kfree(sep);
351 }
352 
353 static void __init lsm_early_cred(struct cred *cred);
354 static void __init lsm_early_task(struct task_struct *task);
355 
356 static int lsm_append(const char *new, char **result);
357 
358 static void __init report_lsm_order(void)
359 {
360 	struct lsm_info **lsm, *early;
361 	int first = 0;
362 
363 	pr_info("initializing lsm=");
364 
365 	/* Report each enabled LSM name, comma separated. */
366 	for (early = __start_early_lsm_info;
367 	     early < __end_early_lsm_info; early++)
368 		if (is_enabled(early))
369 			pr_cont("%s%s", first++ == 0 ? "" : ",", early->name);
370 	for (lsm = ordered_lsms; *lsm; lsm++)
371 		if (is_enabled(*lsm))
372 			pr_cont("%s%s", first++ == 0 ? "" : ",", (*lsm)->name);
373 
374 	pr_cont("\n");
375 }
376 
377 static void __init ordered_lsm_init(void)
378 {
379 	struct lsm_info **lsm;
380 
381 	ordered_lsms = kcalloc(LSM_COUNT + 1, sizeof(*ordered_lsms),
382 			       GFP_KERNEL);
383 
384 	if (chosen_lsm_order) {
385 		if (chosen_major_lsm) {
386 			pr_warn("security=%s is ignored because it is superseded by lsm=%s\n",
387 				chosen_major_lsm, chosen_lsm_order);
388 			chosen_major_lsm = NULL;
389 		}
390 		ordered_lsm_parse(chosen_lsm_order, "cmdline");
391 	} else
392 		ordered_lsm_parse(builtin_lsm_order, "builtin");
393 
394 	for (lsm = ordered_lsms; *lsm; lsm++)
395 		prepare_lsm(*lsm);
396 
397 	report_lsm_order();
398 
399 	init_debug("cred blob size       = %d\n", blob_sizes.lbs_cred);
400 	init_debug("file blob size       = %d\n", blob_sizes.lbs_file);
401 	init_debug("inode blob size      = %d\n", blob_sizes.lbs_inode);
402 	init_debug("ipc blob size        = %d\n", blob_sizes.lbs_ipc);
403 	init_debug("msg_msg blob size    = %d\n", blob_sizes.lbs_msg_msg);
404 	init_debug("superblock blob size = %d\n", blob_sizes.lbs_superblock);
405 	init_debug("task blob size       = %d\n", blob_sizes.lbs_task);
406 	init_debug("xattr slots          = %d\n", blob_sizes.lbs_xattr_count);
407 
408 	/*
409 	 * Create any kmem_caches needed for blobs
410 	 */
411 	if (blob_sizes.lbs_file)
412 		lsm_file_cache = kmem_cache_create("lsm_file_cache",
413 						   blob_sizes.lbs_file, 0,
414 						   SLAB_PANIC, NULL);
415 	if (blob_sizes.lbs_inode)
416 		lsm_inode_cache = kmem_cache_create("lsm_inode_cache",
417 						    blob_sizes.lbs_inode, 0,
418 						    SLAB_PANIC, NULL);
419 
420 	lsm_early_cred((struct cred *) current->cred);
421 	lsm_early_task(current);
422 	for (lsm = ordered_lsms; *lsm; lsm++)
423 		initialize_lsm(*lsm);
424 
425 	kfree(ordered_lsms);
426 }
427 
428 int __init early_security_init(void)
429 {
430 	struct lsm_info *lsm;
431 
432 #define LSM_HOOK(RET, DEFAULT, NAME, ...) \
433 	INIT_HLIST_HEAD(&security_hook_heads.NAME);
434 #include "linux/lsm_hook_defs.h"
435 #undef LSM_HOOK
436 
437 	for (lsm = __start_early_lsm_info; lsm < __end_early_lsm_info; lsm++) {
438 		if (!lsm->enabled)
439 			lsm->enabled = &lsm_enabled_true;
440 		prepare_lsm(lsm);
441 		initialize_lsm(lsm);
442 	}
443 
444 	return 0;
445 }
446 
447 /**
448  * security_init - initializes the security framework
449  *
450  * This should be called early in the kernel initialization sequence.
451  */
452 int __init security_init(void)
453 {
454 	struct lsm_info *lsm;
455 
456 	init_debug("legacy security=%s\n", chosen_major_lsm ? : " *unspecified*");
457 	init_debug("  CONFIG_LSM=%s\n", builtin_lsm_order);
458 	init_debug("boot arg lsm=%s\n", chosen_lsm_order ? : " *unspecified*");
459 
460 	/*
461 	 * Append the names of the early LSM modules now that kmalloc() is
462 	 * available
463 	 */
464 	for (lsm = __start_early_lsm_info; lsm < __end_early_lsm_info; lsm++) {
465 		init_debug("  early started: %s (%s)\n", lsm->name,
466 			   is_enabled(lsm) ? "enabled" : "disabled");
467 		if (lsm->enabled)
468 			lsm_append(lsm->name, &lsm_names);
469 	}
470 
471 	/* Load LSMs in specified order. */
472 	ordered_lsm_init();
473 
474 	return 0;
475 }
476 
477 /* Save user chosen LSM */
478 static int __init choose_major_lsm(char *str)
479 {
480 	chosen_major_lsm = str;
481 	return 1;
482 }
483 __setup("security=", choose_major_lsm);
484 
485 /* Explicitly choose LSM initialization order. */
486 static int __init choose_lsm_order(char *str)
487 {
488 	chosen_lsm_order = str;
489 	return 1;
490 }
491 __setup("lsm=", choose_lsm_order);
492 
493 /* Enable LSM order debugging. */
494 static int __init enable_debug(char *str)
495 {
496 	debug = true;
497 	return 1;
498 }
499 __setup("lsm.debug", enable_debug);
500 
501 static bool match_last_lsm(const char *list, const char *lsm)
502 {
503 	const char *last;
504 
505 	if (WARN_ON(!list || !lsm))
506 		return false;
507 	last = strrchr(list, ',');
508 	if (last)
509 		/* Pass the comma, strcmp() will check for '\0' */
510 		last++;
511 	else
512 		last = list;
513 	return !strcmp(last, lsm);
514 }
515 
516 static int lsm_append(const char *new, char **result)
517 {
518 	char *cp;
519 
520 	if (*result == NULL) {
521 		*result = kstrdup(new, GFP_KERNEL);
522 		if (*result == NULL)
523 			return -ENOMEM;
524 	} else {
525 		/* Check if it is the last registered name */
526 		if (match_last_lsm(*result, new))
527 			return 0;
528 		cp = kasprintf(GFP_KERNEL, "%s,%s", *result, new);
529 		if (cp == NULL)
530 			return -ENOMEM;
531 		kfree(*result);
532 		*result = cp;
533 	}
534 	return 0;
535 }
536 
537 /**
538  * security_add_hooks - Add a modules hooks to the hook lists.
539  * @hooks: the hooks to add
540  * @count: the number of hooks to add
541  * @lsmid: the identification information for the security module
542  *
543  * Each LSM has to register its hooks with the infrastructure.
544  */
545 void __init security_add_hooks(struct security_hook_list *hooks, int count,
546 			       const struct lsm_id *lsmid)
547 {
548 	int i;
549 
550 	/*
551 	 * A security module may call security_add_hooks() more
552 	 * than once during initialization, and LSM initialization
553 	 * is serialized. Landlock is one such case.
554 	 * Look at the previous entry, if there is one, for duplication.
555 	 */
556 	if (lsm_active_cnt == 0 || lsm_idlist[lsm_active_cnt - 1] != lsmid) {
557 		if (lsm_active_cnt >= LSM_CONFIG_COUNT)
558 			panic("%s Too many LSMs registered.\n", __func__);
559 		lsm_idlist[lsm_active_cnt++] = lsmid;
560 	}
561 
562 	for (i = 0; i < count; i++) {
563 		hooks[i].lsmid = lsmid;
564 		hlist_add_tail_rcu(&hooks[i].list, hooks[i].head);
565 	}
566 
567 	/*
568 	 * Don't try to append during early_security_init(), we'll come back
569 	 * and fix this up afterwards.
570 	 */
571 	if (slab_is_available()) {
572 		if (lsm_append(lsmid->name, &lsm_names) < 0)
573 			panic("%s - Cannot get early memory.\n", __func__);
574 	}
575 }
576 
577 int call_blocking_lsm_notifier(enum lsm_event event, void *data)
578 {
579 	return blocking_notifier_call_chain(&blocking_lsm_notifier_chain,
580 					    event, data);
581 }
582 EXPORT_SYMBOL(call_blocking_lsm_notifier);
583 
584 int register_blocking_lsm_notifier(struct notifier_block *nb)
585 {
586 	return blocking_notifier_chain_register(&blocking_lsm_notifier_chain,
587 						nb);
588 }
589 EXPORT_SYMBOL(register_blocking_lsm_notifier);
590 
591 int unregister_blocking_lsm_notifier(struct notifier_block *nb)
592 {
593 	return blocking_notifier_chain_unregister(&blocking_lsm_notifier_chain,
594 						  nb);
595 }
596 EXPORT_SYMBOL(unregister_blocking_lsm_notifier);
597 
598 /**
599  * lsm_cred_alloc - allocate a composite cred blob
600  * @cred: the cred that needs a blob
601  * @gfp: allocation type
602  *
603  * Allocate the cred blob for all the modules
604  *
605  * Returns 0, or -ENOMEM if memory can't be allocated.
606  */
607 static int lsm_cred_alloc(struct cred *cred, gfp_t gfp)
608 {
609 	if (blob_sizes.lbs_cred == 0) {
610 		cred->security = NULL;
611 		return 0;
612 	}
613 
614 	cred->security = kzalloc(blob_sizes.lbs_cred, gfp);
615 	if (cred->security == NULL)
616 		return -ENOMEM;
617 	return 0;
618 }
619 
620 /**
621  * lsm_early_cred - during initialization allocate a composite cred blob
622  * @cred: the cred that needs a blob
623  *
624  * Allocate the cred blob for all the modules
625  */
626 static void __init lsm_early_cred(struct cred *cred)
627 {
628 	int rc = lsm_cred_alloc(cred, GFP_KERNEL);
629 
630 	if (rc)
631 		panic("%s: Early cred alloc failed.\n", __func__);
632 }
633 
634 /**
635  * lsm_file_alloc - allocate a composite file blob
636  * @file: the file that needs a blob
637  *
638  * Allocate the file blob for all the modules
639  *
640  * Returns 0, or -ENOMEM if memory can't be allocated.
641  */
642 static int lsm_file_alloc(struct file *file)
643 {
644 	if (!lsm_file_cache) {
645 		file->f_security = NULL;
646 		return 0;
647 	}
648 
649 	file->f_security = kmem_cache_zalloc(lsm_file_cache, GFP_KERNEL);
650 	if (file->f_security == NULL)
651 		return -ENOMEM;
652 	return 0;
653 }
654 
655 /**
656  * lsm_inode_alloc - allocate a composite inode blob
657  * @inode: the inode that needs a blob
658  *
659  * Allocate the inode blob for all the modules
660  *
661  * Returns 0, or -ENOMEM if memory can't be allocated.
662  */
663 int lsm_inode_alloc(struct inode *inode)
664 {
665 	if (!lsm_inode_cache) {
666 		inode->i_security = NULL;
667 		return 0;
668 	}
669 
670 	inode->i_security = kmem_cache_zalloc(lsm_inode_cache, GFP_NOFS);
671 	if (inode->i_security == NULL)
672 		return -ENOMEM;
673 	return 0;
674 }
675 
676 /**
677  * lsm_task_alloc - allocate a composite task blob
678  * @task: the task that needs a blob
679  *
680  * Allocate the task blob for all the modules
681  *
682  * Returns 0, or -ENOMEM if memory can't be allocated.
683  */
684 static int lsm_task_alloc(struct task_struct *task)
685 {
686 	if (blob_sizes.lbs_task == 0) {
687 		task->security = NULL;
688 		return 0;
689 	}
690 
691 	task->security = kzalloc(blob_sizes.lbs_task, GFP_KERNEL);
692 	if (task->security == NULL)
693 		return -ENOMEM;
694 	return 0;
695 }
696 
697 /**
698  * lsm_ipc_alloc - allocate a composite ipc blob
699  * @kip: the ipc that needs a blob
700  *
701  * Allocate the ipc blob for all the modules
702  *
703  * Returns 0, or -ENOMEM if memory can't be allocated.
704  */
705 static int lsm_ipc_alloc(struct kern_ipc_perm *kip)
706 {
707 	if (blob_sizes.lbs_ipc == 0) {
708 		kip->security = NULL;
709 		return 0;
710 	}
711 
712 	kip->security = kzalloc(blob_sizes.lbs_ipc, GFP_KERNEL);
713 	if (kip->security == NULL)
714 		return -ENOMEM;
715 	return 0;
716 }
717 
718 /**
719  * lsm_msg_msg_alloc - allocate a composite msg_msg blob
720  * @mp: the msg_msg that needs a blob
721  *
722  * Allocate the ipc blob for all the modules
723  *
724  * Returns 0, or -ENOMEM if memory can't be allocated.
725  */
726 static int lsm_msg_msg_alloc(struct msg_msg *mp)
727 {
728 	if (blob_sizes.lbs_msg_msg == 0) {
729 		mp->security = NULL;
730 		return 0;
731 	}
732 
733 	mp->security = kzalloc(blob_sizes.lbs_msg_msg, GFP_KERNEL);
734 	if (mp->security == NULL)
735 		return -ENOMEM;
736 	return 0;
737 }
738 
739 /**
740  * lsm_early_task - during initialization allocate a composite task blob
741  * @task: the task that needs a blob
742  *
743  * Allocate the task blob for all the modules
744  */
745 static void __init lsm_early_task(struct task_struct *task)
746 {
747 	int rc = lsm_task_alloc(task);
748 
749 	if (rc)
750 		panic("%s: Early task alloc failed.\n", __func__);
751 }
752 
753 /**
754  * lsm_superblock_alloc - allocate a composite superblock blob
755  * @sb: the superblock that needs a blob
756  *
757  * Allocate the superblock blob for all the modules
758  *
759  * Returns 0, or -ENOMEM if memory can't be allocated.
760  */
761 static int lsm_superblock_alloc(struct super_block *sb)
762 {
763 	if (blob_sizes.lbs_superblock == 0) {
764 		sb->s_security = NULL;
765 		return 0;
766 	}
767 
768 	sb->s_security = kzalloc(blob_sizes.lbs_superblock, GFP_KERNEL);
769 	if (sb->s_security == NULL)
770 		return -ENOMEM;
771 	return 0;
772 }
773 
774 /**
775  * lsm_fill_user_ctx - Fill a user space lsm_ctx structure
776  * @uctx: a userspace LSM context to be filled
777  * @uctx_len: available uctx size (input), used uctx size (output)
778  * @val: the new LSM context value
779  * @val_len: the size of the new LSM context value
780  * @id: LSM id
781  * @flags: LSM defined flags
782  *
783  * Fill all of the fields in a userspace lsm_ctx structure.
784  *
785  * Returns 0 on success, -E2BIG if userspace buffer is not large enough,
786  * -EFAULT on a copyout error, -ENOMEM if memory can't be allocated.
787  */
788 int lsm_fill_user_ctx(struct lsm_ctx __user *uctx, size_t *uctx_len,
789 		      void *val, size_t val_len,
790 		      u64 id, u64 flags)
791 {
792 	struct lsm_ctx *nctx = NULL;
793 	size_t nctx_len;
794 	int rc = 0;
795 
796 	nctx_len = ALIGN(struct_size(nctx, ctx, val_len), sizeof(void *));
797 	if (nctx_len > *uctx_len) {
798 		rc = -E2BIG;
799 		goto out;
800 	}
801 
802 	nctx = kzalloc(nctx_len, GFP_KERNEL);
803 	if (nctx == NULL) {
804 		rc = -ENOMEM;
805 		goto out;
806 	}
807 	nctx->id = id;
808 	nctx->flags = flags;
809 	nctx->len = nctx_len;
810 	nctx->ctx_len = val_len;
811 	memcpy(nctx->ctx, val, val_len);
812 
813 	if (copy_to_user(uctx, nctx, nctx_len))
814 		rc = -EFAULT;
815 
816 out:
817 	kfree(nctx);
818 	*uctx_len = nctx_len;
819 	return rc;
820 }
821 
822 /*
823  * The default value of the LSM hook is defined in linux/lsm_hook_defs.h and
824  * can be accessed with:
825  *
826  *	LSM_RET_DEFAULT(<hook_name>)
827  *
828  * The macros below define static constants for the default value of each
829  * LSM hook.
830  */
831 #define LSM_RET_DEFAULT(NAME) (NAME##_default)
832 #define DECLARE_LSM_RET_DEFAULT_void(DEFAULT, NAME)
833 #define DECLARE_LSM_RET_DEFAULT_int(DEFAULT, NAME) \
834 	static const int __maybe_unused LSM_RET_DEFAULT(NAME) = (DEFAULT);
835 #define LSM_HOOK(RET, DEFAULT, NAME, ...) \
836 	DECLARE_LSM_RET_DEFAULT_##RET(DEFAULT, NAME)
837 
838 #include <linux/lsm_hook_defs.h>
839 #undef LSM_HOOK
840 
841 /*
842  * Hook list operation macros.
843  *
844  * call_void_hook:
845  *	This is a hook that does not return a value.
846  *
847  * call_int_hook:
848  *	This is a hook that returns a value.
849  */
850 
851 #define call_void_hook(FUNC, ...)				\
852 	do {							\
853 		struct security_hook_list *P;			\
854 								\
855 		hlist_for_each_entry(P, &security_hook_heads.FUNC, list) \
856 			P->hook.FUNC(__VA_ARGS__);		\
857 	} while (0)
858 
859 #define call_int_hook(FUNC, IRC, ...) ({			\
860 	int RC = IRC;						\
861 	do {							\
862 		struct security_hook_list *P;			\
863 								\
864 		hlist_for_each_entry(P, &security_hook_heads.FUNC, list) { \
865 			RC = P->hook.FUNC(__VA_ARGS__);		\
866 			if (RC != 0)				\
867 				break;				\
868 		}						\
869 	} while (0);						\
870 	RC;							\
871 })
872 
873 /* Security operations */
874 
875 /**
876  * security_binder_set_context_mgr() - Check if becoming binder ctx mgr is ok
877  * @mgr: task credentials of current binder process
878  *
879  * Check whether @mgr is allowed to be the binder context manager.
880  *
881  * Return: Return 0 if permission is granted.
882  */
883 int security_binder_set_context_mgr(const struct cred *mgr)
884 {
885 	return call_int_hook(binder_set_context_mgr, 0, mgr);
886 }
887 
888 /**
889  * security_binder_transaction() - Check if a binder transaction is allowed
890  * @from: sending process
891  * @to: receiving process
892  *
893  * Check whether @from is allowed to invoke a binder transaction call to @to.
894  *
895  * Return: Returns 0 if permission is granted.
896  */
897 int security_binder_transaction(const struct cred *from,
898 				const struct cred *to)
899 {
900 	return call_int_hook(binder_transaction, 0, from, to);
901 }
902 
903 /**
904  * security_binder_transfer_binder() - Check if a binder transfer is allowed
905  * @from: sending process
906  * @to: receiving process
907  *
908  * Check whether @from is allowed to transfer a binder reference to @to.
909  *
910  * Return: Returns 0 if permission is granted.
911  */
912 int security_binder_transfer_binder(const struct cred *from,
913 				    const struct cred *to)
914 {
915 	return call_int_hook(binder_transfer_binder, 0, from, to);
916 }
917 
918 /**
919  * security_binder_transfer_file() - Check if a binder file xfer is allowed
920  * @from: sending process
921  * @to: receiving process
922  * @file: file being transferred
923  *
924  * Check whether @from is allowed to transfer @file to @to.
925  *
926  * Return: Returns 0 if permission is granted.
927  */
928 int security_binder_transfer_file(const struct cred *from,
929 				  const struct cred *to, const struct file *file)
930 {
931 	return call_int_hook(binder_transfer_file, 0, from, to, file);
932 }
933 
934 /**
935  * security_ptrace_access_check() - Check if tracing is allowed
936  * @child: target process
937  * @mode: PTRACE_MODE flags
938  *
939  * Check permission before allowing the current process to trace the @child
940  * process.  Security modules may also want to perform a process tracing check
941  * during an execve in the set_security or apply_creds hooks of tracing check
942  * during an execve in the bprm_set_creds hook of binprm_security_ops if the
943  * process is being traced and its security attributes would be changed by the
944  * execve.
945  *
946  * Return: Returns 0 if permission is granted.
947  */
948 int security_ptrace_access_check(struct task_struct *child, unsigned int mode)
949 {
950 	return call_int_hook(ptrace_access_check, 0, child, mode);
951 }
952 
953 /**
954  * security_ptrace_traceme() - Check if tracing is allowed
955  * @parent: tracing process
956  *
957  * Check that the @parent process has sufficient permission to trace the
958  * current process before allowing the current process to present itself to the
959  * @parent process for tracing.
960  *
961  * Return: Returns 0 if permission is granted.
962  */
963 int security_ptrace_traceme(struct task_struct *parent)
964 {
965 	return call_int_hook(ptrace_traceme, 0, parent);
966 }
967 
968 /**
969  * security_capget() - Get the capability sets for a process
970  * @target: target process
971  * @effective: effective capability set
972  * @inheritable: inheritable capability set
973  * @permitted: permitted capability set
974  *
975  * Get the @effective, @inheritable, and @permitted capability sets for the
976  * @target process.  The hook may also perform permission checking to determine
977  * if the current process is allowed to see the capability sets of the @target
978  * process.
979  *
980  * Return: Returns 0 if the capability sets were successfully obtained.
981  */
982 int security_capget(const struct task_struct *target,
983 		    kernel_cap_t *effective,
984 		    kernel_cap_t *inheritable,
985 		    kernel_cap_t *permitted)
986 {
987 	return call_int_hook(capget, 0, target,
988 			     effective, inheritable, permitted);
989 }
990 
991 /**
992  * security_capset() - Set the capability sets for a process
993  * @new: new credentials for the target process
994  * @old: current credentials of the target process
995  * @effective: effective capability set
996  * @inheritable: inheritable capability set
997  * @permitted: permitted capability set
998  *
999  * Set the @effective, @inheritable, and @permitted capability sets for the
1000  * current process.
1001  *
1002  * Return: Returns 0 and update @new if permission is granted.
1003  */
1004 int security_capset(struct cred *new, const struct cred *old,
1005 		    const kernel_cap_t *effective,
1006 		    const kernel_cap_t *inheritable,
1007 		    const kernel_cap_t *permitted)
1008 {
1009 	return call_int_hook(capset, 0, new, old,
1010 			     effective, inheritable, permitted);
1011 }
1012 
1013 /**
1014  * security_capable() - Check if a process has the necessary capability
1015  * @cred: credentials to examine
1016  * @ns: user namespace
1017  * @cap: capability requested
1018  * @opts: capability check options
1019  *
1020  * Check whether the @tsk process has the @cap capability in the indicated
1021  * credentials.  @cap contains the capability <include/linux/capability.h>.
1022  * @opts contains options for the capable check <include/linux/security.h>.
1023  *
1024  * Return: Returns 0 if the capability is granted.
1025  */
1026 int security_capable(const struct cred *cred,
1027 		     struct user_namespace *ns,
1028 		     int cap,
1029 		     unsigned int opts)
1030 {
1031 	return call_int_hook(capable, 0, cred, ns, cap, opts);
1032 }
1033 
1034 /**
1035  * security_quotactl() - Check if a quotactl() syscall is allowed for this fs
1036  * @cmds: commands
1037  * @type: type
1038  * @id: id
1039  * @sb: filesystem
1040  *
1041  * Check whether the quotactl syscall is allowed for this @sb.
1042  *
1043  * Return: Returns 0 if permission is granted.
1044  */
1045 int security_quotactl(int cmds, int type, int id, const struct super_block *sb)
1046 {
1047 	return call_int_hook(quotactl, 0, cmds, type, id, sb);
1048 }
1049 
1050 /**
1051  * security_quota_on() - Check if QUOTAON is allowed for a dentry
1052  * @dentry: dentry
1053  *
1054  * Check whether QUOTAON is allowed for @dentry.
1055  *
1056  * Return: Returns 0 if permission is granted.
1057  */
1058 int security_quota_on(struct dentry *dentry)
1059 {
1060 	return call_int_hook(quota_on, 0, dentry);
1061 }
1062 
1063 /**
1064  * security_syslog() - Check if accessing the kernel message ring is allowed
1065  * @type: SYSLOG_ACTION_* type
1066  *
1067  * Check permission before accessing the kernel message ring or changing
1068  * logging to the console.  See the syslog(2) manual page for an explanation of
1069  * the @type values.
1070  *
1071  * Return: Return 0 if permission is granted.
1072  */
1073 int security_syslog(int type)
1074 {
1075 	return call_int_hook(syslog, 0, type);
1076 }
1077 
1078 /**
1079  * security_settime64() - Check if changing the system time is allowed
1080  * @ts: new time
1081  * @tz: timezone
1082  *
1083  * Check permission to change the system time, struct timespec64 is defined in
1084  * <include/linux/time64.h> and timezone is defined in <include/linux/time.h>.
1085  *
1086  * Return: Returns 0 if permission is granted.
1087  */
1088 int security_settime64(const struct timespec64 *ts, const struct timezone *tz)
1089 {
1090 	return call_int_hook(settime, 0, ts, tz);
1091 }
1092 
1093 /**
1094  * security_vm_enough_memory_mm() - Check if allocating a new mem map is allowed
1095  * @mm: mm struct
1096  * @pages: number of pages
1097  *
1098  * Check permissions for allocating a new virtual mapping.  If all LSMs return
1099  * a positive value, __vm_enough_memory() will be called with cap_sys_admin
1100  * set. If at least one LSM returns 0 or negative, __vm_enough_memory() will be
1101  * called with cap_sys_admin cleared.
1102  *
1103  * Return: Returns 0 if permission is granted by the LSM infrastructure to the
1104  *         caller.
1105  */
1106 int security_vm_enough_memory_mm(struct mm_struct *mm, long pages)
1107 {
1108 	struct security_hook_list *hp;
1109 	int cap_sys_admin = 1;
1110 	int rc;
1111 
1112 	/*
1113 	 * The module will respond with a positive value if
1114 	 * it thinks the __vm_enough_memory() call should be
1115 	 * made with the cap_sys_admin set. If all of the modules
1116 	 * agree that it should be set it will. If any module
1117 	 * thinks it should not be set it won't.
1118 	 */
1119 	hlist_for_each_entry(hp, &security_hook_heads.vm_enough_memory, list) {
1120 		rc = hp->hook.vm_enough_memory(mm, pages);
1121 		if (rc <= 0) {
1122 			cap_sys_admin = 0;
1123 			break;
1124 		}
1125 	}
1126 	return __vm_enough_memory(mm, pages, cap_sys_admin);
1127 }
1128 
1129 /**
1130  * security_bprm_creds_for_exec() - Prepare the credentials for exec()
1131  * @bprm: binary program information
1132  *
1133  * If the setup in prepare_exec_creds did not setup @bprm->cred->security
1134  * properly for executing @bprm->file, update the LSM's portion of
1135  * @bprm->cred->security to be what commit_creds needs to install for the new
1136  * program.  This hook may also optionally check permissions (e.g. for
1137  * transitions between security domains).  The hook must set @bprm->secureexec
1138  * to 1 if AT_SECURE should be set to request libc enable secure mode.  @bprm
1139  * contains the linux_binprm structure.
1140  *
1141  * Return: Returns 0 if the hook is successful and permission is granted.
1142  */
1143 int security_bprm_creds_for_exec(struct linux_binprm *bprm)
1144 {
1145 	return call_int_hook(bprm_creds_for_exec, 0, bprm);
1146 }
1147 
1148 /**
1149  * security_bprm_creds_from_file() - Update linux_binprm creds based on file
1150  * @bprm: binary program information
1151  * @file: associated file
1152  *
1153  * If @file is setpcap, suid, sgid or otherwise marked to change privilege upon
1154  * exec, update @bprm->cred to reflect that change. This is called after
1155  * finding the binary that will be executed without an interpreter.  This
1156  * ensures that the credentials will not be derived from a script that the
1157  * binary will need to reopen, which when reopend may end up being a completely
1158  * different file.  This hook may also optionally check permissions (e.g. for
1159  * transitions between security domains).  The hook must set @bprm->secureexec
1160  * to 1 if AT_SECURE should be set to request libc enable secure mode.  The
1161  * hook must add to @bprm->per_clear any personality flags that should be
1162  * cleared from current->personality.  @bprm contains the linux_binprm
1163  * structure.
1164  *
1165  * Return: Returns 0 if the hook is successful and permission is granted.
1166  */
1167 int security_bprm_creds_from_file(struct linux_binprm *bprm, const struct file *file)
1168 {
1169 	return call_int_hook(bprm_creds_from_file, 0, bprm, file);
1170 }
1171 
1172 /**
1173  * security_bprm_check() - Mediate binary handler search
1174  * @bprm: binary program information
1175  *
1176  * This hook mediates the point when a search for a binary handler will begin.
1177  * It allows a check against the @bprm->cred->security value which was set in
1178  * the preceding creds_for_exec call.  The argv list and envp list are reliably
1179  * available in @bprm.  This hook may be called multiple times during a single
1180  * execve.  @bprm contains the linux_binprm structure.
1181  *
1182  * Return: Returns 0 if the hook is successful and permission is granted.
1183  */
1184 int security_bprm_check(struct linux_binprm *bprm)
1185 {
1186 	int ret;
1187 
1188 	ret = call_int_hook(bprm_check_security, 0, bprm);
1189 	if (ret)
1190 		return ret;
1191 	return ima_bprm_check(bprm);
1192 }
1193 
1194 /**
1195  * security_bprm_committing_creds() - Install creds for a process during exec()
1196  * @bprm: binary program information
1197  *
1198  * Prepare to install the new security attributes of a process being
1199  * transformed by an execve operation, based on the old credentials pointed to
1200  * by @current->cred and the information set in @bprm->cred by the
1201  * bprm_creds_for_exec hook.  @bprm points to the linux_binprm structure.  This
1202  * hook is a good place to perform state changes on the process such as closing
1203  * open file descriptors to which access will no longer be granted when the
1204  * attributes are changed.  This is called immediately before commit_creds().
1205  */
1206 void security_bprm_committing_creds(const struct linux_binprm *bprm)
1207 {
1208 	call_void_hook(bprm_committing_creds, bprm);
1209 }
1210 
1211 /**
1212  * security_bprm_committed_creds() - Tidy up after cred install during exec()
1213  * @bprm: binary program information
1214  *
1215  * Tidy up after the installation of the new security attributes of a process
1216  * being transformed by an execve operation.  The new credentials have, by this
1217  * point, been set to @current->cred.  @bprm points to the linux_binprm
1218  * structure.  This hook is a good place to perform state changes on the
1219  * process such as clearing out non-inheritable signal state.  This is called
1220  * immediately after commit_creds().
1221  */
1222 void security_bprm_committed_creds(const struct linux_binprm *bprm)
1223 {
1224 	call_void_hook(bprm_committed_creds, bprm);
1225 }
1226 
1227 /**
1228  * security_fs_context_submount() - Initialise fc->security
1229  * @fc: new filesystem context
1230  * @reference: dentry reference for submount/remount
1231  *
1232  * Fill out the ->security field for a new fs_context.
1233  *
1234  * Return: Returns 0 on success or negative error code on failure.
1235  */
1236 int security_fs_context_submount(struct fs_context *fc, struct super_block *reference)
1237 {
1238 	return call_int_hook(fs_context_submount, 0, fc, reference);
1239 }
1240 
1241 /**
1242  * security_fs_context_dup() - Duplicate a fs_context LSM blob
1243  * @fc: destination filesystem context
1244  * @src_fc: source filesystem context
1245  *
1246  * Allocate and attach a security structure to sc->security.  This pointer is
1247  * initialised to NULL by the caller.  @fc indicates the new filesystem context.
1248  * @src_fc indicates the original filesystem context.
1249  *
1250  * Return: Returns 0 on success or a negative error code on failure.
1251  */
1252 int security_fs_context_dup(struct fs_context *fc, struct fs_context *src_fc)
1253 {
1254 	return call_int_hook(fs_context_dup, 0, fc, src_fc);
1255 }
1256 
1257 /**
1258  * security_fs_context_parse_param() - Configure a filesystem context
1259  * @fc: filesystem context
1260  * @param: filesystem parameter
1261  *
1262  * Userspace provided a parameter to configure a superblock.  The LSM can
1263  * consume the parameter or return it to the caller for use elsewhere.
1264  *
1265  * Return: If the parameter is used by the LSM it should return 0, if it is
1266  *         returned to the caller -ENOPARAM is returned, otherwise a negative
1267  *         error code is returned.
1268  */
1269 int security_fs_context_parse_param(struct fs_context *fc,
1270 				    struct fs_parameter *param)
1271 {
1272 	struct security_hook_list *hp;
1273 	int trc;
1274 	int rc = -ENOPARAM;
1275 
1276 	hlist_for_each_entry(hp, &security_hook_heads.fs_context_parse_param,
1277 			     list) {
1278 		trc = hp->hook.fs_context_parse_param(fc, param);
1279 		if (trc == 0)
1280 			rc = 0;
1281 		else if (trc != -ENOPARAM)
1282 			return trc;
1283 	}
1284 	return rc;
1285 }
1286 
1287 /**
1288  * security_sb_alloc() - Allocate a super_block LSM blob
1289  * @sb: filesystem superblock
1290  *
1291  * Allocate and attach a security structure to the sb->s_security field.  The
1292  * s_security field is initialized to NULL when the structure is allocated.
1293  * @sb contains the super_block structure to be modified.
1294  *
1295  * Return: Returns 0 if operation was successful.
1296  */
1297 int security_sb_alloc(struct super_block *sb)
1298 {
1299 	int rc = lsm_superblock_alloc(sb);
1300 
1301 	if (unlikely(rc))
1302 		return rc;
1303 	rc = call_int_hook(sb_alloc_security, 0, sb);
1304 	if (unlikely(rc))
1305 		security_sb_free(sb);
1306 	return rc;
1307 }
1308 
1309 /**
1310  * security_sb_delete() - Release super_block LSM associated objects
1311  * @sb: filesystem superblock
1312  *
1313  * Release objects tied to a superblock (e.g. inodes).  @sb contains the
1314  * super_block structure being released.
1315  */
1316 void security_sb_delete(struct super_block *sb)
1317 {
1318 	call_void_hook(sb_delete, sb);
1319 }
1320 
1321 /**
1322  * security_sb_free() - Free a super_block LSM blob
1323  * @sb: filesystem superblock
1324  *
1325  * Deallocate and clear the sb->s_security field.  @sb contains the super_block
1326  * structure to be modified.
1327  */
1328 void security_sb_free(struct super_block *sb)
1329 {
1330 	call_void_hook(sb_free_security, sb);
1331 	kfree(sb->s_security);
1332 	sb->s_security = NULL;
1333 }
1334 
1335 /**
1336  * security_free_mnt_opts() - Free memory associated with mount options
1337  * @mnt_opts: LSM processed mount options
1338  *
1339  * Free memory associated with @mnt_ops.
1340  */
1341 void security_free_mnt_opts(void **mnt_opts)
1342 {
1343 	if (!*mnt_opts)
1344 		return;
1345 	call_void_hook(sb_free_mnt_opts, *mnt_opts);
1346 	*mnt_opts = NULL;
1347 }
1348 EXPORT_SYMBOL(security_free_mnt_opts);
1349 
1350 /**
1351  * security_sb_eat_lsm_opts() - Consume LSM mount options
1352  * @options: mount options
1353  * @mnt_opts: LSM processed mount options
1354  *
1355  * Eat (scan @options) and save them in @mnt_opts.
1356  *
1357  * Return: Returns 0 on success, negative values on failure.
1358  */
1359 int security_sb_eat_lsm_opts(char *options, void **mnt_opts)
1360 {
1361 	return call_int_hook(sb_eat_lsm_opts, 0, options, mnt_opts);
1362 }
1363 EXPORT_SYMBOL(security_sb_eat_lsm_opts);
1364 
1365 /**
1366  * security_sb_mnt_opts_compat() - Check if new mount options are allowed
1367  * @sb: filesystem superblock
1368  * @mnt_opts: new mount options
1369  *
1370  * Determine if the new mount options in @mnt_opts are allowed given the
1371  * existing mounted filesystem at @sb.  @sb superblock being compared.
1372  *
1373  * Return: Returns 0 if options are compatible.
1374  */
1375 int security_sb_mnt_opts_compat(struct super_block *sb,
1376 				void *mnt_opts)
1377 {
1378 	return call_int_hook(sb_mnt_opts_compat, 0, sb, mnt_opts);
1379 }
1380 EXPORT_SYMBOL(security_sb_mnt_opts_compat);
1381 
1382 /**
1383  * security_sb_remount() - Verify no incompatible mount changes during remount
1384  * @sb: filesystem superblock
1385  * @mnt_opts: (re)mount options
1386  *
1387  * Extracts security system specific mount options and verifies no changes are
1388  * being made to those options.
1389  *
1390  * Return: Returns 0 if permission is granted.
1391  */
1392 int security_sb_remount(struct super_block *sb,
1393 			void *mnt_opts)
1394 {
1395 	return call_int_hook(sb_remount, 0, sb, mnt_opts);
1396 }
1397 EXPORT_SYMBOL(security_sb_remount);
1398 
1399 /**
1400  * security_sb_kern_mount() - Check if a kernel mount is allowed
1401  * @sb: filesystem superblock
1402  *
1403  * Mount this @sb if allowed by permissions.
1404  *
1405  * Return: Returns 0 if permission is granted.
1406  */
1407 int security_sb_kern_mount(const struct super_block *sb)
1408 {
1409 	return call_int_hook(sb_kern_mount, 0, sb);
1410 }
1411 
1412 /**
1413  * security_sb_show_options() - Output the mount options for a superblock
1414  * @m: output file
1415  * @sb: filesystem superblock
1416  *
1417  * Show (print on @m) mount options for this @sb.
1418  *
1419  * Return: Returns 0 on success, negative values on failure.
1420  */
1421 int security_sb_show_options(struct seq_file *m, struct super_block *sb)
1422 {
1423 	return call_int_hook(sb_show_options, 0, m, sb);
1424 }
1425 
1426 /**
1427  * security_sb_statfs() - Check if accessing fs stats is allowed
1428  * @dentry: superblock handle
1429  *
1430  * Check permission before obtaining filesystem statistics for the @mnt
1431  * mountpoint.  @dentry is a handle on the superblock for the filesystem.
1432  *
1433  * Return: Returns 0 if permission is granted.
1434  */
1435 int security_sb_statfs(struct dentry *dentry)
1436 {
1437 	return call_int_hook(sb_statfs, 0, dentry);
1438 }
1439 
1440 /**
1441  * security_sb_mount() - Check permission for mounting a filesystem
1442  * @dev_name: filesystem backing device
1443  * @path: mount point
1444  * @type: filesystem type
1445  * @flags: mount flags
1446  * @data: filesystem specific data
1447  *
1448  * Check permission before an object specified by @dev_name is mounted on the
1449  * mount point named by @nd.  For an ordinary mount, @dev_name identifies a
1450  * device if the file system type requires a device.  For a remount
1451  * (@flags & MS_REMOUNT), @dev_name is irrelevant.  For a loopback/bind mount
1452  * (@flags & MS_BIND), @dev_name identifies the	pathname of the object being
1453  * mounted.
1454  *
1455  * Return: Returns 0 if permission is granted.
1456  */
1457 int security_sb_mount(const char *dev_name, const struct path *path,
1458 		      const char *type, unsigned long flags, void *data)
1459 {
1460 	return call_int_hook(sb_mount, 0, dev_name, path, type, flags, data);
1461 }
1462 
1463 /**
1464  * security_sb_umount() - Check permission for unmounting a filesystem
1465  * @mnt: mounted filesystem
1466  * @flags: unmount flags
1467  *
1468  * Check permission before the @mnt file system is unmounted.
1469  *
1470  * Return: Returns 0 if permission is granted.
1471  */
1472 int security_sb_umount(struct vfsmount *mnt, int flags)
1473 {
1474 	return call_int_hook(sb_umount, 0, mnt, flags);
1475 }
1476 
1477 /**
1478  * security_sb_pivotroot() - Check permissions for pivoting the rootfs
1479  * @old_path: new location for current rootfs
1480  * @new_path: location of the new rootfs
1481  *
1482  * Check permission before pivoting the root filesystem.
1483  *
1484  * Return: Returns 0 if permission is granted.
1485  */
1486 int security_sb_pivotroot(const struct path *old_path,
1487 			  const struct path *new_path)
1488 {
1489 	return call_int_hook(sb_pivotroot, 0, old_path, new_path);
1490 }
1491 
1492 /**
1493  * security_sb_set_mnt_opts() - Set the mount options for a filesystem
1494  * @sb: filesystem superblock
1495  * @mnt_opts: binary mount options
1496  * @kern_flags: kernel flags (in)
1497  * @set_kern_flags: kernel flags (out)
1498  *
1499  * Set the security relevant mount options used for a superblock.
1500  *
1501  * Return: Returns 0 on success, error on failure.
1502  */
1503 int security_sb_set_mnt_opts(struct super_block *sb,
1504 			     void *mnt_opts,
1505 			     unsigned long kern_flags,
1506 			     unsigned long *set_kern_flags)
1507 {
1508 	return call_int_hook(sb_set_mnt_opts,
1509 			     mnt_opts ? -EOPNOTSUPP : 0, sb,
1510 			     mnt_opts, kern_flags, set_kern_flags);
1511 }
1512 EXPORT_SYMBOL(security_sb_set_mnt_opts);
1513 
1514 /**
1515  * security_sb_clone_mnt_opts() - Duplicate superblock mount options
1516  * @oldsb: source superblock
1517  * @newsb: destination superblock
1518  * @kern_flags: kernel flags (in)
1519  * @set_kern_flags: kernel flags (out)
1520  *
1521  * Copy all security options from a given superblock to another.
1522  *
1523  * Return: Returns 0 on success, error on failure.
1524  */
1525 int security_sb_clone_mnt_opts(const struct super_block *oldsb,
1526 			       struct super_block *newsb,
1527 			       unsigned long kern_flags,
1528 			       unsigned long *set_kern_flags)
1529 {
1530 	return call_int_hook(sb_clone_mnt_opts, 0, oldsb, newsb,
1531 			     kern_flags, set_kern_flags);
1532 }
1533 EXPORT_SYMBOL(security_sb_clone_mnt_opts);
1534 
1535 /**
1536  * security_move_mount() - Check permissions for moving a mount
1537  * @from_path: source mount point
1538  * @to_path: destination mount point
1539  *
1540  * Check permission before a mount is moved.
1541  *
1542  * Return: Returns 0 if permission is granted.
1543  */
1544 int security_move_mount(const struct path *from_path,
1545 			const struct path *to_path)
1546 {
1547 	return call_int_hook(move_mount, 0, from_path, to_path);
1548 }
1549 
1550 /**
1551  * security_path_notify() - Check if setting a watch is allowed
1552  * @path: file path
1553  * @mask: event mask
1554  * @obj_type: file path type
1555  *
1556  * Check permissions before setting a watch on events as defined by @mask, on
1557  * an object at @path, whose type is defined by @obj_type.
1558  *
1559  * Return: Returns 0 if permission is granted.
1560  */
1561 int security_path_notify(const struct path *path, u64 mask,
1562 			 unsigned int obj_type)
1563 {
1564 	return call_int_hook(path_notify, 0, path, mask, obj_type);
1565 }
1566 
1567 /**
1568  * security_inode_alloc() - Allocate an inode LSM blob
1569  * @inode: the inode
1570  *
1571  * Allocate and attach a security structure to @inode->i_security.  The
1572  * i_security field is initialized to NULL when the inode structure is
1573  * allocated.
1574  *
1575  * Return: Return 0 if operation was successful.
1576  */
1577 int security_inode_alloc(struct inode *inode)
1578 {
1579 	int rc = lsm_inode_alloc(inode);
1580 
1581 	if (unlikely(rc))
1582 		return rc;
1583 	rc = call_int_hook(inode_alloc_security, 0, inode);
1584 	if (unlikely(rc))
1585 		security_inode_free(inode);
1586 	return rc;
1587 }
1588 
1589 static void inode_free_by_rcu(struct rcu_head *head)
1590 {
1591 	/*
1592 	 * The rcu head is at the start of the inode blob
1593 	 */
1594 	kmem_cache_free(lsm_inode_cache, head);
1595 }
1596 
1597 /**
1598  * security_inode_free() - Free an inode's LSM blob
1599  * @inode: the inode
1600  *
1601  * Deallocate the inode security structure and set @inode->i_security to NULL.
1602  */
1603 void security_inode_free(struct inode *inode)
1604 {
1605 	integrity_inode_free(inode);
1606 	call_void_hook(inode_free_security, inode);
1607 	/*
1608 	 * The inode may still be referenced in a path walk and
1609 	 * a call to security_inode_permission() can be made
1610 	 * after inode_free_security() is called. Ideally, the VFS
1611 	 * wouldn't do this, but fixing that is a much harder
1612 	 * job. For now, simply free the i_security via RCU, and
1613 	 * leave the current inode->i_security pointer intact.
1614 	 * The inode will be freed after the RCU grace period too.
1615 	 */
1616 	if (inode->i_security)
1617 		call_rcu((struct rcu_head *)inode->i_security,
1618 			 inode_free_by_rcu);
1619 }
1620 
1621 /**
1622  * security_dentry_init_security() - Perform dentry initialization
1623  * @dentry: the dentry to initialize
1624  * @mode: mode used to determine resource type
1625  * @name: name of the last path component
1626  * @xattr_name: name of the security/LSM xattr
1627  * @ctx: pointer to the resulting LSM context
1628  * @ctxlen: length of @ctx
1629  *
1630  * Compute a context for a dentry as the inode is not yet available since NFSv4
1631  * has no label backed by an EA anyway.  It is important to note that
1632  * @xattr_name does not need to be free'd by the caller, it is a static string.
1633  *
1634  * Return: Returns 0 on success, negative values on failure.
1635  */
1636 int security_dentry_init_security(struct dentry *dentry, int mode,
1637 				  const struct qstr *name,
1638 				  const char **xattr_name, void **ctx,
1639 				  u32 *ctxlen)
1640 {
1641 	struct security_hook_list *hp;
1642 	int rc;
1643 
1644 	/*
1645 	 * Only one module will provide a security context.
1646 	 */
1647 	hlist_for_each_entry(hp, &security_hook_heads.dentry_init_security,
1648 			     list) {
1649 		rc = hp->hook.dentry_init_security(dentry, mode, name,
1650 						   xattr_name, ctx, ctxlen);
1651 		if (rc != LSM_RET_DEFAULT(dentry_init_security))
1652 			return rc;
1653 	}
1654 	return LSM_RET_DEFAULT(dentry_init_security);
1655 }
1656 EXPORT_SYMBOL(security_dentry_init_security);
1657 
1658 /**
1659  * security_dentry_create_files_as() - Perform dentry initialization
1660  * @dentry: the dentry to initialize
1661  * @mode: mode used to determine resource type
1662  * @name: name of the last path component
1663  * @old: creds to use for LSM context calculations
1664  * @new: creds to modify
1665  *
1666  * Compute a context for a dentry as the inode is not yet available and set
1667  * that context in passed in creds so that new files are created using that
1668  * context. Context is calculated using the passed in creds and not the creds
1669  * of the caller.
1670  *
1671  * Return: Returns 0 on success, error on failure.
1672  */
1673 int security_dentry_create_files_as(struct dentry *dentry, int mode,
1674 				    struct qstr *name,
1675 				    const struct cred *old, struct cred *new)
1676 {
1677 	return call_int_hook(dentry_create_files_as, 0, dentry, mode,
1678 			     name, old, new);
1679 }
1680 EXPORT_SYMBOL(security_dentry_create_files_as);
1681 
1682 /**
1683  * security_inode_init_security() - Initialize an inode's LSM context
1684  * @inode: the inode
1685  * @dir: parent directory
1686  * @qstr: last component of the pathname
1687  * @initxattrs: callback function to write xattrs
1688  * @fs_data: filesystem specific data
1689  *
1690  * Obtain the security attribute name suffix and value to set on a newly
1691  * created inode and set up the incore security field for the new inode.  This
1692  * hook is called by the fs code as part of the inode creation transaction and
1693  * provides for atomic labeling of the inode, unlike the post_create/mkdir/...
1694  * hooks called by the VFS.
1695  *
1696  * The hook function is expected to populate the xattrs array, by calling
1697  * lsm_get_xattr_slot() to retrieve the slots reserved by the security module
1698  * with the lbs_xattr_count field of the lsm_blob_sizes structure.  For each
1699  * slot, the hook function should set ->name to the attribute name suffix
1700  * (e.g. selinux), to allocate ->value (will be freed by the caller) and set it
1701  * to the attribute value, to set ->value_len to the length of the value.  If
1702  * the security module does not use security attributes or does not wish to put
1703  * a security attribute on this particular inode, then it should return
1704  * -EOPNOTSUPP to skip this processing.
1705  *
1706  * Return: Returns 0 if the LSM successfully initialized all of the inode
1707  *         security attributes that are required, negative values otherwise.
1708  */
1709 int security_inode_init_security(struct inode *inode, struct inode *dir,
1710 				 const struct qstr *qstr,
1711 				 const initxattrs initxattrs, void *fs_data)
1712 {
1713 	struct security_hook_list *hp;
1714 	struct xattr *new_xattrs = NULL;
1715 	int ret = -EOPNOTSUPP, xattr_count = 0;
1716 
1717 	if (unlikely(IS_PRIVATE(inode)))
1718 		return 0;
1719 
1720 	if (!blob_sizes.lbs_xattr_count)
1721 		return 0;
1722 
1723 	if (initxattrs) {
1724 		/* Allocate +1 for EVM and +1 as terminator. */
1725 		new_xattrs = kcalloc(blob_sizes.lbs_xattr_count + 2,
1726 				     sizeof(*new_xattrs), GFP_NOFS);
1727 		if (!new_xattrs)
1728 			return -ENOMEM;
1729 	}
1730 
1731 	hlist_for_each_entry(hp, &security_hook_heads.inode_init_security,
1732 			     list) {
1733 		ret = hp->hook.inode_init_security(inode, dir, qstr, new_xattrs,
1734 						  &xattr_count);
1735 		if (ret && ret != -EOPNOTSUPP)
1736 			goto out;
1737 		/*
1738 		 * As documented in lsm_hooks.h, -EOPNOTSUPP in this context
1739 		 * means that the LSM is not willing to provide an xattr, not
1740 		 * that it wants to signal an error. Thus, continue to invoke
1741 		 * the remaining LSMs.
1742 		 */
1743 	}
1744 
1745 	/* If initxattrs() is NULL, xattr_count is zero, skip the call. */
1746 	if (!xattr_count)
1747 		goto out;
1748 
1749 	ret = evm_inode_init_security(inode, dir, qstr, new_xattrs,
1750 				      &xattr_count);
1751 	if (ret)
1752 		goto out;
1753 	ret = initxattrs(inode, new_xattrs, fs_data);
1754 out:
1755 	for (; xattr_count > 0; xattr_count--)
1756 		kfree(new_xattrs[xattr_count - 1].value);
1757 	kfree(new_xattrs);
1758 	return (ret == -EOPNOTSUPP) ? 0 : ret;
1759 }
1760 EXPORT_SYMBOL(security_inode_init_security);
1761 
1762 /**
1763  * security_inode_init_security_anon() - Initialize an anonymous inode
1764  * @inode: the inode
1765  * @name: the anonymous inode class
1766  * @context_inode: an optional related inode
1767  *
1768  * Set up the incore security field for the new anonymous inode and return
1769  * whether the inode creation is permitted by the security module or not.
1770  *
1771  * Return: Returns 0 on success, -EACCES if the security module denies the
1772  * creation of this inode, or another -errno upon other errors.
1773  */
1774 int security_inode_init_security_anon(struct inode *inode,
1775 				      const struct qstr *name,
1776 				      const struct inode *context_inode)
1777 {
1778 	return call_int_hook(inode_init_security_anon, 0, inode, name,
1779 			     context_inode);
1780 }
1781 
1782 #ifdef CONFIG_SECURITY_PATH
1783 /**
1784  * security_path_mknod() - Check if creating a special file is allowed
1785  * @dir: parent directory
1786  * @dentry: new file
1787  * @mode: new file mode
1788  * @dev: device number
1789  *
1790  * Check permissions when creating a file. Note that this hook is called even
1791  * if mknod operation is being done for a regular file.
1792  *
1793  * Return: Returns 0 if permission is granted.
1794  */
1795 int security_path_mknod(const struct path *dir, struct dentry *dentry,
1796 			umode_t mode, unsigned int dev)
1797 {
1798 	if (unlikely(IS_PRIVATE(d_backing_inode(dir->dentry))))
1799 		return 0;
1800 	return call_int_hook(path_mknod, 0, dir, dentry, mode, dev);
1801 }
1802 EXPORT_SYMBOL(security_path_mknod);
1803 
1804 /**
1805  * security_path_mkdir() - Check if creating a new directory is allowed
1806  * @dir: parent directory
1807  * @dentry: new directory
1808  * @mode: new directory mode
1809  *
1810  * Check permissions to create a new directory in the existing directory.
1811  *
1812  * Return: Returns 0 if permission is granted.
1813  */
1814 int security_path_mkdir(const struct path *dir, struct dentry *dentry,
1815 			umode_t mode)
1816 {
1817 	if (unlikely(IS_PRIVATE(d_backing_inode(dir->dentry))))
1818 		return 0;
1819 	return call_int_hook(path_mkdir, 0, dir, dentry, mode);
1820 }
1821 EXPORT_SYMBOL(security_path_mkdir);
1822 
1823 /**
1824  * security_path_rmdir() - Check if removing a directory is allowed
1825  * @dir: parent directory
1826  * @dentry: directory to remove
1827  *
1828  * Check the permission to remove a directory.
1829  *
1830  * Return: Returns 0 if permission is granted.
1831  */
1832 int security_path_rmdir(const struct path *dir, struct dentry *dentry)
1833 {
1834 	if (unlikely(IS_PRIVATE(d_backing_inode(dir->dentry))))
1835 		return 0;
1836 	return call_int_hook(path_rmdir, 0, dir, dentry);
1837 }
1838 
1839 /**
1840  * security_path_unlink() - Check if removing a hard link is allowed
1841  * @dir: parent directory
1842  * @dentry: file
1843  *
1844  * Check the permission to remove a hard link to a file.
1845  *
1846  * Return: Returns 0 if permission is granted.
1847  */
1848 int security_path_unlink(const struct path *dir, struct dentry *dentry)
1849 {
1850 	if (unlikely(IS_PRIVATE(d_backing_inode(dir->dentry))))
1851 		return 0;
1852 	return call_int_hook(path_unlink, 0, dir, dentry);
1853 }
1854 EXPORT_SYMBOL(security_path_unlink);
1855 
1856 /**
1857  * security_path_symlink() - Check if creating a symbolic link is allowed
1858  * @dir: parent directory
1859  * @dentry: symbolic link
1860  * @old_name: file pathname
1861  *
1862  * Check the permission to create a symbolic link to a file.
1863  *
1864  * Return: Returns 0 if permission is granted.
1865  */
1866 int security_path_symlink(const struct path *dir, struct dentry *dentry,
1867 			  const char *old_name)
1868 {
1869 	if (unlikely(IS_PRIVATE(d_backing_inode(dir->dentry))))
1870 		return 0;
1871 	return call_int_hook(path_symlink, 0, dir, dentry, old_name);
1872 }
1873 
1874 /**
1875  * security_path_link - Check if creating a hard link is allowed
1876  * @old_dentry: existing file
1877  * @new_dir: new parent directory
1878  * @new_dentry: new link
1879  *
1880  * Check permission before creating a new hard link to a file.
1881  *
1882  * Return: Returns 0 if permission is granted.
1883  */
1884 int security_path_link(struct dentry *old_dentry, const struct path *new_dir,
1885 		       struct dentry *new_dentry)
1886 {
1887 	if (unlikely(IS_PRIVATE(d_backing_inode(old_dentry))))
1888 		return 0;
1889 	return call_int_hook(path_link, 0, old_dentry, new_dir, new_dentry);
1890 }
1891 
1892 /**
1893  * security_path_rename() - Check if renaming a file is allowed
1894  * @old_dir: parent directory of the old file
1895  * @old_dentry: the old file
1896  * @new_dir: parent directory of the new file
1897  * @new_dentry: the new file
1898  * @flags: flags
1899  *
1900  * Check for permission to rename a file or directory.
1901  *
1902  * Return: Returns 0 if permission is granted.
1903  */
1904 int security_path_rename(const struct path *old_dir, struct dentry *old_dentry,
1905 			 const struct path *new_dir, struct dentry *new_dentry,
1906 			 unsigned int flags)
1907 {
1908 	if (unlikely(IS_PRIVATE(d_backing_inode(old_dentry)) ||
1909 		     (d_is_positive(new_dentry) &&
1910 		      IS_PRIVATE(d_backing_inode(new_dentry)))))
1911 		return 0;
1912 
1913 	return call_int_hook(path_rename, 0, old_dir, old_dentry, new_dir,
1914 			     new_dentry, flags);
1915 }
1916 EXPORT_SYMBOL(security_path_rename);
1917 
1918 /**
1919  * security_path_truncate() - Check if truncating a file is allowed
1920  * @path: file
1921  *
1922  * Check permission before truncating the file indicated by path.  Note that
1923  * truncation permissions may also be checked based on already opened files,
1924  * using the security_file_truncate() hook.
1925  *
1926  * Return: Returns 0 if permission is granted.
1927  */
1928 int security_path_truncate(const struct path *path)
1929 {
1930 	if (unlikely(IS_PRIVATE(d_backing_inode(path->dentry))))
1931 		return 0;
1932 	return call_int_hook(path_truncate, 0, path);
1933 }
1934 
1935 /**
1936  * security_path_chmod() - Check if changing the file's mode is allowed
1937  * @path: file
1938  * @mode: new mode
1939  *
1940  * Check for permission to change a mode of the file @path. The new mode is
1941  * specified in @mode which is a bitmask of constants from
1942  * <include/uapi/linux/stat.h>.
1943  *
1944  * Return: Returns 0 if permission is granted.
1945  */
1946 int security_path_chmod(const struct path *path, umode_t mode)
1947 {
1948 	if (unlikely(IS_PRIVATE(d_backing_inode(path->dentry))))
1949 		return 0;
1950 	return call_int_hook(path_chmod, 0, path, mode);
1951 }
1952 
1953 /**
1954  * security_path_chown() - Check if changing the file's owner/group is allowed
1955  * @path: file
1956  * @uid: file owner
1957  * @gid: file group
1958  *
1959  * Check for permission to change owner/group of a file or directory.
1960  *
1961  * Return: Returns 0 if permission is granted.
1962  */
1963 int security_path_chown(const struct path *path, kuid_t uid, kgid_t gid)
1964 {
1965 	if (unlikely(IS_PRIVATE(d_backing_inode(path->dentry))))
1966 		return 0;
1967 	return call_int_hook(path_chown, 0, path, uid, gid);
1968 }
1969 
1970 /**
1971  * security_path_chroot() - Check if changing the root directory is allowed
1972  * @path: directory
1973  *
1974  * Check for permission to change root directory.
1975  *
1976  * Return: Returns 0 if permission is granted.
1977  */
1978 int security_path_chroot(const struct path *path)
1979 {
1980 	return call_int_hook(path_chroot, 0, path);
1981 }
1982 #endif /* CONFIG_SECURITY_PATH */
1983 
1984 /**
1985  * security_inode_create() - Check if creating a file is allowed
1986  * @dir: the parent directory
1987  * @dentry: the file being created
1988  * @mode: requested file mode
1989  *
1990  * Check permission to create a regular file.
1991  *
1992  * Return: Returns 0 if permission is granted.
1993  */
1994 int security_inode_create(struct inode *dir, struct dentry *dentry,
1995 			  umode_t mode)
1996 {
1997 	if (unlikely(IS_PRIVATE(dir)))
1998 		return 0;
1999 	return call_int_hook(inode_create, 0, dir, dentry, mode);
2000 }
2001 EXPORT_SYMBOL_GPL(security_inode_create);
2002 
2003 /**
2004  * security_inode_link() - Check if creating a hard link is allowed
2005  * @old_dentry: existing file
2006  * @dir: new parent directory
2007  * @new_dentry: new link
2008  *
2009  * Check permission before creating a new hard link to a file.
2010  *
2011  * Return: Returns 0 if permission is granted.
2012  */
2013 int security_inode_link(struct dentry *old_dentry, struct inode *dir,
2014 			struct dentry *new_dentry)
2015 {
2016 	if (unlikely(IS_PRIVATE(d_backing_inode(old_dentry))))
2017 		return 0;
2018 	return call_int_hook(inode_link, 0, old_dentry, dir, new_dentry);
2019 }
2020 
2021 /**
2022  * security_inode_unlink() - Check if removing a hard link is allowed
2023  * @dir: parent directory
2024  * @dentry: file
2025  *
2026  * Check the permission to remove a hard link to a file.
2027  *
2028  * Return: Returns 0 if permission is granted.
2029  */
2030 int security_inode_unlink(struct inode *dir, struct dentry *dentry)
2031 {
2032 	if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
2033 		return 0;
2034 	return call_int_hook(inode_unlink, 0, dir, dentry);
2035 }
2036 
2037 /**
2038  * security_inode_symlink() - Check if creating a symbolic link is allowed
2039  * @dir: parent directory
2040  * @dentry: symbolic link
2041  * @old_name: existing filename
2042  *
2043  * Check the permission to create a symbolic link to a file.
2044  *
2045  * Return: Returns 0 if permission is granted.
2046  */
2047 int security_inode_symlink(struct inode *dir, struct dentry *dentry,
2048 			   const char *old_name)
2049 {
2050 	if (unlikely(IS_PRIVATE(dir)))
2051 		return 0;
2052 	return call_int_hook(inode_symlink, 0, dir, dentry, old_name);
2053 }
2054 
2055 /**
2056  * security_inode_mkdir() - Check if creation a new director is allowed
2057  * @dir: parent directory
2058  * @dentry: new directory
2059  * @mode: new directory mode
2060  *
2061  * Check permissions to create a new directory in the existing directory
2062  * associated with inode structure @dir.
2063  *
2064  * Return: Returns 0 if permission is granted.
2065  */
2066 int security_inode_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
2067 {
2068 	if (unlikely(IS_PRIVATE(dir)))
2069 		return 0;
2070 	return call_int_hook(inode_mkdir, 0, dir, dentry, mode);
2071 }
2072 EXPORT_SYMBOL_GPL(security_inode_mkdir);
2073 
2074 /**
2075  * security_inode_rmdir() - Check if removing a directory is allowed
2076  * @dir: parent directory
2077  * @dentry: directory to be removed
2078  *
2079  * Check the permission to remove a directory.
2080  *
2081  * Return: Returns 0 if permission is granted.
2082  */
2083 int security_inode_rmdir(struct inode *dir, struct dentry *dentry)
2084 {
2085 	if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
2086 		return 0;
2087 	return call_int_hook(inode_rmdir, 0, dir, dentry);
2088 }
2089 
2090 /**
2091  * security_inode_mknod() - Check if creating a special file is allowed
2092  * @dir: parent directory
2093  * @dentry: new file
2094  * @mode: new file mode
2095  * @dev: device number
2096  *
2097  * Check permissions when creating a special file (or a socket or a fifo file
2098  * created via the mknod system call).  Note that if mknod operation is being
2099  * done for a regular file, then the create hook will be called and not this
2100  * hook.
2101  *
2102  * Return: Returns 0 if permission is granted.
2103  */
2104 int security_inode_mknod(struct inode *dir, struct dentry *dentry,
2105 			 umode_t mode, dev_t dev)
2106 {
2107 	if (unlikely(IS_PRIVATE(dir)))
2108 		return 0;
2109 	return call_int_hook(inode_mknod, 0, dir, dentry, mode, dev);
2110 }
2111 
2112 /**
2113  * security_inode_rename() - Check if renaming a file is allowed
2114  * @old_dir: parent directory of the old file
2115  * @old_dentry: the old file
2116  * @new_dir: parent directory of the new file
2117  * @new_dentry: the new file
2118  * @flags: flags
2119  *
2120  * Check for permission to rename a file or directory.
2121  *
2122  * Return: Returns 0 if permission is granted.
2123  */
2124 int security_inode_rename(struct inode *old_dir, struct dentry *old_dentry,
2125 			  struct inode *new_dir, struct dentry *new_dentry,
2126 			  unsigned int flags)
2127 {
2128 	if (unlikely(IS_PRIVATE(d_backing_inode(old_dentry)) ||
2129 		     (d_is_positive(new_dentry) &&
2130 		      IS_PRIVATE(d_backing_inode(new_dentry)))))
2131 		return 0;
2132 
2133 	if (flags & RENAME_EXCHANGE) {
2134 		int err = call_int_hook(inode_rename, 0, new_dir, new_dentry,
2135 					old_dir, old_dentry);
2136 		if (err)
2137 			return err;
2138 	}
2139 
2140 	return call_int_hook(inode_rename, 0, old_dir, old_dentry,
2141 			     new_dir, new_dentry);
2142 }
2143 
2144 /**
2145  * security_inode_readlink() - Check if reading a symbolic link is allowed
2146  * @dentry: link
2147  *
2148  * Check the permission to read the symbolic link.
2149  *
2150  * Return: Returns 0 if permission is granted.
2151  */
2152 int security_inode_readlink(struct dentry *dentry)
2153 {
2154 	if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
2155 		return 0;
2156 	return call_int_hook(inode_readlink, 0, dentry);
2157 }
2158 
2159 /**
2160  * security_inode_follow_link() - Check if following a symbolic link is allowed
2161  * @dentry: link dentry
2162  * @inode: link inode
2163  * @rcu: true if in RCU-walk mode
2164  *
2165  * Check permission to follow a symbolic link when looking up a pathname.  If
2166  * @rcu is true, @inode is not stable.
2167  *
2168  * Return: Returns 0 if permission is granted.
2169  */
2170 int security_inode_follow_link(struct dentry *dentry, struct inode *inode,
2171 			       bool rcu)
2172 {
2173 	if (unlikely(IS_PRIVATE(inode)))
2174 		return 0;
2175 	return call_int_hook(inode_follow_link, 0, dentry, inode, rcu);
2176 }
2177 
2178 /**
2179  * security_inode_permission() - Check if accessing an inode is allowed
2180  * @inode: inode
2181  * @mask: access mask
2182  *
2183  * Check permission before accessing an inode.  This hook is called by the
2184  * existing Linux permission function, so a security module can use it to
2185  * provide additional checking for existing Linux permission checks.  Notice
2186  * that this hook is called when a file is opened (as well as many other
2187  * operations), whereas the file_security_ops permission hook is called when
2188  * the actual read/write operations are performed.
2189  *
2190  * Return: Returns 0 if permission is granted.
2191  */
2192 int security_inode_permission(struct inode *inode, int mask)
2193 {
2194 	if (unlikely(IS_PRIVATE(inode)))
2195 		return 0;
2196 	return call_int_hook(inode_permission, 0, inode, mask);
2197 }
2198 
2199 /**
2200  * security_inode_setattr() - Check if setting file attributes is allowed
2201  * @idmap: idmap of the mount
2202  * @dentry: file
2203  * @attr: new attributes
2204  *
2205  * Check permission before setting file attributes.  Note that the kernel call
2206  * to notify_change is performed from several locations, whenever file
2207  * attributes change (such as when a file is truncated, chown/chmod operations,
2208  * transferring disk quotas, etc).
2209  *
2210  * Return: Returns 0 if permission is granted.
2211  */
2212 int security_inode_setattr(struct mnt_idmap *idmap,
2213 			   struct dentry *dentry, struct iattr *attr)
2214 {
2215 	int ret;
2216 
2217 	if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
2218 		return 0;
2219 	ret = call_int_hook(inode_setattr, 0, dentry, attr);
2220 	if (ret)
2221 		return ret;
2222 	return evm_inode_setattr(idmap, dentry, attr);
2223 }
2224 EXPORT_SYMBOL_GPL(security_inode_setattr);
2225 
2226 /**
2227  * security_inode_getattr() - Check if getting file attributes is allowed
2228  * @path: file
2229  *
2230  * Check permission before obtaining file attributes.
2231  *
2232  * Return: Returns 0 if permission is granted.
2233  */
2234 int security_inode_getattr(const struct path *path)
2235 {
2236 	if (unlikely(IS_PRIVATE(d_backing_inode(path->dentry))))
2237 		return 0;
2238 	return call_int_hook(inode_getattr, 0, path);
2239 }
2240 
2241 /**
2242  * security_inode_setxattr() - Check if setting file xattrs is allowed
2243  * @idmap: idmap of the mount
2244  * @dentry: file
2245  * @name: xattr name
2246  * @value: xattr value
2247  * @size: size of xattr value
2248  * @flags: flags
2249  *
2250  * Check permission before setting the extended attributes.
2251  *
2252  * Return: Returns 0 if permission is granted.
2253  */
2254 int security_inode_setxattr(struct mnt_idmap *idmap,
2255 			    struct dentry *dentry, const char *name,
2256 			    const void *value, size_t size, int flags)
2257 {
2258 	int ret;
2259 
2260 	if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
2261 		return 0;
2262 	/*
2263 	 * SELinux and Smack integrate the cap call,
2264 	 * so assume that all LSMs supplying this call do so.
2265 	 */
2266 	ret = call_int_hook(inode_setxattr, 1, idmap, dentry, name, value,
2267 			    size, flags);
2268 
2269 	if (ret == 1)
2270 		ret = cap_inode_setxattr(dentry, name, value, size, flags);
2271 	if (ret)
2272 		return ret;
2273 	ret = ima_inode_setxattr(dentry, name, value, size);
2274 	if (ret)
2275 		return ret;
2276 	return evm_inode_setxattr(idmap, dentry, name, value, size);
2277 }
2278 
2279 /**
2280  * security_inode_set_acl() - Check if setting posix acls is allowed
2281  * @idmap: idmap of the mount
2282  * @dentry: file
2283  * @acl_name: acl name
2284  * @kacl: acl struct
2285  *
2286  * Check permission before setting posix acls, the posix acls in @kacl are
2287  * identified by @acl_name.
2288  *
2289  * Return: Returns 0 if permission is granted.
2290  */
2291 int security_inode_set_acl(struct mnt_idmap *idmap,
2292 			   struct dentry *dentry, const char *acl_name,
2293 			   struct posix_acl *kacl)
2294 {
2295 	int ret;
2296 
2297 	if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
2298 		return 0;
2299 	ret = call_int_hook(inode_set_acl, 0, idmap, dentry, acl_name,
2300 			    kacl);
2301 	if (ret)
2302 		return ret;
2303 	ret = ima_inode_set_acl(idmap, dentry, acl_name, kacl);
2304 	if (ret)
2305 		return ret;
2306 	return evm_inode_set_acl(idmap, dentry, acl_name, kacl);
2307 }
2308 
2309 /**
2310  * security_inode_get_acl() - Check if reading posix acls is allowed
2311  * @idmap: idmap of the mount
2312  * @dentry: file
2313  * @acl_name: acl name
2314  *
2315  * Check permission before getting osix acls, the posix acls are identified by
2316  * @acl_name.
2317  *
2318  * Return: Returns 0 if permission is granted.
2319  */
2320 int security_inode_get_acl(struct mnt_idmap *idmap,
2321 			   struct dentry *dentry, const char *acl_name)
2322 {
2323 	if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
2324 		return 0;
2325 	return call_int_hook(inode_get_acl, 0, idmap, dentry, acl_name);
2326 }
2327 
2328 /**
2329  * security_inode_remove_acl() - Check if removing a posix acl is allowed
2330  * @idmap: idmap of the mount
2331  * @dentry: file
2332  * @acl_name: acl name
2333  *
2334  * Check permission before removing posix acls, the posix acls are identified
2335  * by @acl_name.
2336  *
2337  * Return: Returns 0 if permission is granted.
2338  */
2339 int security_inode_remove_acl(struct mnt_idmap *idmap,
2340 			      struct dentry *dentry, const char *acl_name)
2341 {
2342 	int ret;
2343 
2344 	if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
2345 		return 0;
2346 	ret = call_int_hook(inode_remove_acl, 0, idmap, dentry, acl_name);
2347 	if (ret)
2348 		return ret;
2349 	ret = ima_inode_remove_acl(idmap, dentry, acl_name);
2350 	if (ret)
2351 		return ret;
2352 	return evm_inode_remove_acl(idmap, dentry, acl_name);
2353 }
2354 
2355 /**
2356  * security_inode_post_setxattr() - Update the inode after a setxattr operation
2357  * @dentry: file
2358  * @name: xattr name
2359  * @value: xattr value
2360  * @size: xattr value size
2361  * @flags: flags
2362  *
2363  * Update inode security field after successful setxattr operation.
2364  */
2365 void security_inode_post_setxattr(struct dentry *dentry, const char *name,
2366 				  const void *value, size_t size, int flags)
2367 {
2368 	if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
2369 		return;
2370 	call_void_hook(inode_post_setxattr, dentry, name, value, size, flags);
2371 	evm_inode_post_setxattr(dentry, name, value, size);
2372 }
2373 
2374 /**
2375  * security_inode_getxattr() - Check if xattr access is allowed
2376  * @dentry: file
2377  * @name: xattr name
2378  *
2379  * Check permission before obtaining the extended attributes identified by
2380  * @name for @dentry.
2381  *
2382  * Return: Returns 0 if permission is granted.
2383  */
2384 int security_inode_getxattr(struct dentry *dentry, const char *name)
2385 {
2386 	if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
2387 		return 0;
2388 	return call_int_hook(inode_getxattr, 0, dentry, name);
2389 }
2390 
2391 /**
2392  * security_inode_listxattr() - Check if listing xattrs is allowed
2393  * @dentry: file
2394  *
2395  * Check permission before obtaining the list of extended attribute names for
2396  * @dentry.
2397  *
2398  * Return: Returns 0 if permission is granted.
2399  */
2400 int security_inode_listxattr(struct dentry *dentry)
2401 {
2402 	if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
2403 		return 0;
2404 	return call_int_hook(inode_listxattr, 0, dentry);
2405 }
2406 
2407 /**
2408  * security_inode_removexattr() - Check if removing an xattr is allowed
2409  * @idmap: idmap of the mount
2410  * @dentry: file
2411  * @name: xattr name
2412  *
2413  * Check permission before removing the extended attribute identified by @name
2414  * for @dentry.
2415  *
2416  * Return: Returns 0 if permission is granted.
2417  */
2418 int security_inode_removexattr(struct mnt_idmap *idmap,
2419 			       struct dentry *dentry, const char *name)
2420 {
2421 	int ret;
2422 
2423 	if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
2424 		return 0;
2425 	/*
2426 	 * SELinux and Smack integrate the cap call,
2427 	 * so assume that all LSMs supplying this call do so.
2428 	 */
2429 	ret = call_int_hook(inode_removexattr, 1, idmap, dentry, name);
2430 	if (ret == 1)
2431 		ret = cap_inode_removexattr(idmap, dentry, name);
2432 	if (ret)
2433 		return ret;
2434 	ret = ima_inode_removexattr(dentry, name);
2435 	if (ret)
2436 		return ret;
2437 	return evm_inode_removexattr(idmap, dentry, name);
2438 }
2439 
2440 /**
2441  * security_inode_need_killpriv() - Check if security_inode_killpriv() required
2442  * @dentry: associated dentry
2443  *
2444  * Called when an inode has been changed to determine if
2445  * security_inode_killpriv() should be called.
2446  *
2447  * Return: Return <0 on error to abort the inode change operation, return 0 if
2448  *         security_inode_killpriv() does not need to be called, return >0 if
2449  *         security_inode_killpriv() does need to be called.
2450  */
2451 int security_inode_need_killpriv(struct dentry *dentry)
2452 {
2453 	return call_int_hook(inode_need_killpriv, 0, dentry);
2454 }
2455 
2456 /**
2457  * security_inode_killpriv() - The setuid bit is removed, update LSM state
2458  * @idmap: idmap of the mount
2459  * @dentry: associated dentry
2460  *
2461  * The @dentry's setuid bit is being removed.  Remove similar security labels.
2462  * Called with the dentry->d_inode->i_mutex held.
2463  *
2464  * Return: Return 0 on success.  If error is returned, then the operation
2465  *         causing setuid bit removal is failed.
2466  */
2467 int security_inode_killpriv(struct mnt_idmap *idmap,
2468 			    struct dentry *dentry)
2469 {
2470 	return call_int_hook(inode_killpriv, 0, idmap, dentry);
2471 }
2472 
2473 /**
2474  * security_inode_getsecurity() - Get the xattr security label of an inode
2475  * @idmap: idmap of the mount
2476  * @inode: inode
2477  * @name: xattr name
2478  * @buffer: security label buffer
2479  * @alloc: allocation flag
2480  *
2481  * Retrieve a copy of the extended attribute representation of the security
2482  * label associated with @name for @inode via @buffer.  Note that @name is the
2483  * remainder of the attribute name after the security prefix has been removed.
2484  * @alloc is used to specify if the call should return a value via the buffer
2485  * or just the value length.
2486  *
2487  * Return: Returns size of buffer on success.
2488  */
2489 int security_inode_getsecurity(struct mnt_idmap *idmap,
2490 			       struct inode *inode, const char *name,
2491 			       void **buffer, bool alloc)
2492 {
2493 	struct security_hook_list *hp;
2494 	int rc;
2495 
2496 	if (unlikely(IS_PRIVATE(inode)))
2497 		return LSM_RET_DEFAULT(inode_getsecurity);
2498 	/*
2499 	 * Only one module will provide an attribute with a given name.
2500 	 */
2501 	hlist_for_each_entry(hp, &security_hook_heads.inode_getsecurity, list) {
2502 		rc = hp->hook.inode_getsecurity(idmap, inode, name, buffer,
2503 						alloc);
2504 		if (rc != LSM_RET_DEFAULT(inode_getsecurity))
2505 			return rc;
2506 	}
2507 	return LSM_RET_DEFAULT(inode_getsecurity);
2508 }
2509 
2510 /**
2511  * security_inode_setsecurity() - Set the xattr security label of an inode
2512  * @inode: inode
2513  * @name: xattr name
2514  * @value: security label
2515  * @size: length of security label
2516  * @flags: flags
2517  *
2518  * Set the security label associated with @name for @inode from the extended
2519  * attribute value @value.  @size indicates the size of the @value in bytes.
2520  * @flags may be XATTR_CREATE, XATTR_REPLACE, or 0. Note that @name is the
2521  * remainder of the attribute name after the security. prefix has been removed.
2522  *
2523  * Return: Returns 0 on success.
2524  */
2525 int security_inode_setsecurity(struct inode *inode, const char *name,
2526 			       const void *value, size_t size, int flags)
2527 {
2528 	struct security_hook_list *hp;
2529 	int rc;
2530 
2531 	if (unlikely(IS_PRIVATE(inode)))
2532 		return LSM_RET_DEFAULT(inode_setsecurity);
2533 	/*
2534 	 * Only one module will provide an attribute with a given name.
2535 	 */
2536 	hlist_for_each_entry(hp, &security_hook_heads.inode_setsecurity, list) {
2537 		rc = hp->hook.inode_setsecurity(inode, name, value, size,
2538 						flags);
2539 		if (rc != LSM_RET_DEFAULT(inode_setsecurity))
2540 			return rc;
2541 	}
2542 	return LSM_RET_DEFAULT(inode_setsecurity);
2543 }
2544 
2545 /**
2546  * security_inode_listsecurity() - List the xattr security label names
2547  * @inode: inode
2548  * @buffer: buffer
2549  * @buffer_size: size of buffer
2550  *
2551  * Copy the extended attribute names for the security labels associated with
2552  * @inode into @buffer.  The maximum size of @buffer is specified by
2553  * @buffer_size.  @buffer may be NULL to request the size of the buffer
2554  * required.
2555  *
2556  * Return: Returns number of bytes used/required on success.
2557  */
2558 int security_inode_listsecurity(struct inode *inode,
2559 				char *buffer, size_t buffer_size)
2560 {
2561 	if (unlikely(IS_PRIVATE(inode)))
2562 		return 0;
2563 	return call_int_hook(inode_listsecurity, 0, inode, buffer, buffer_size);
2564 }
2565 EXPORT_SYMBOL(security_inode_listsecurity);
2566 
2567 /**
2568  * security_inode_getsecid() - Get an inode's secid
2569  * @inode: inode
2570  * @secid: secid to return
2571  *
2572  * Get the secid associated with the node.  In case of failure, @secid will be
2573  * set to zero.
2574  */
2575 void security_inode_getsecid(struct inode *inode, u32 *secid)
2576 {
2577 	call_void_hook(inode_getsecid, inode, secid);
2578 }
2579 
2580 /**
2581  * security_inode_copy_up() - Create new creds for an overlayfs copy-up op
2582  * @src: union dentry of copy-up file
2583  * @new: newly created creds
2584  *
2585  * A file is about to be copied up from lower layer to upper layer of overlay
2586  * filesystem. Security module can prepare a set of new creds and modify as
2587  * need be and return new creds. Caller will switch to new creds temporarily to
2588  * create new file and release newly allocated creds.
2589  *
2590  * Return: Returns 0 on success or a negative error code on error.
2591  */
2592 int security_inode_copy_up(struct dentry *src, struct cred **new)
2593 {
2594 	return call_int_hook(inode_copy_up, 0, src, new);
2595 }
2596 EXPORT_SYMBOL(security_inode_copy_up);
2597 
2598 /**
2599  * security_inode_copy_up_xattr() - Filter xattrs in an overlayfs copy-up op
2600  * @name: xattr name
2601  *
2602  * Filter the xattrs being copied up when a unioned file is copied up from a
2603  * lower layer to the union/overlay layer.   The caller is responsible for
2604  * reading and writing the xattrs, this hook is merely a filter.
2605  *
2606  * Return: Returns 0 to accept the xattr, 1 to discard the xattr, -EOPNOTSUPP
2607  *         if the security module does not know about attribute, or a negative
2608  *         error code to abort the copy up.
2609  */
2610 int security_inode_copy_up_xattr(const char *name)
2611 {
2612 	struct security_hook_list *hp;
2613 	int rc;
2614 
2615 	/*
2616 	 * The implementation can return 0 (accept the xattr), 1 (discard the
2617 	 * xattr), -EOPNOTSUPP if it does not know anything about the xattr or
2618 	 * any other error code in case of an error.
2619 	 */
2620 	hlist_for_each_entry(hp,
2621 			     &security_hook_heads.inode_copy_up_xattr, list) {
2622 		rc = hp->hook.inode_copy_up_xattr(name);
2623 		if (rc != LSM_RET_DEFAULT(inode_copy_up_xattr))
2624 			return rc;
2625 	}
2626 
2627 	return evm_inode_copy_up_xattr(name);
2628 }
2629 EXPORT_SYMBOL(security_inode_copy_up_xattr);
2630 
2631 /**
2632  * security_kernfs_init_security() - Init LSM context for a kernfs node
2633  * @kn_dir: parent kernfs node
2634  * @kn: the kernfs node to initialize
2635  *
2636  * Initialize the security context of a newly created kernfs node based on its
2637  * own and its parent's attributes.
2638  *
2639  * Return: Returns 0 if permission is granted.
2640  */
2641 int security_kernfs_init_security(struct kernfs_node *kn_dir,
2642 				  struct kernfs_node *kn)
2643 {
2644 	return call_int_hook(kernfs_init_security, 0, kn_dir, kn);
2645 }
2646 
2647 /**
2648  * security_file_permission() - Check file permissions
2649  * @file: file
2650  * @mask: requested permissions
2651  *
2652  * Check file permissions before accessing an open file.  This hook is called
2653  * by various operations that read or write files.  A security module can use
2654  * this hook to perform additional checking on these operations, e.g. to
2655  * revalidate permissions on use to support privilege bracketing or policy
2656  * changes.  Notice that this hook is used when the actual read/write
2657  * operations are performed, whereas the inode_security_ops hook is called when
2658  * a file is opened (as well as many other operations).  Although this hook can
2659  * be used to revalidate permissions for various system call operations that
2660  * read or write files, it does not address the revalidation of permissions for
2661  * memory-mapped files.  Security modules must handle this separately if they
2662  * need such revalidation.
2663  *
2664  * Return: Returns 0 if permission is granted.
2665  */
2666 int security_file_permission(struct file *file, int mask)
2667 {
2668 	return call_int_hook(file_permission, 0, file, mask);
2669 }
2670 
2671 /**
2672  * security_file_alloc() - Allocate and init a file's LSM blob
2673  * @file: the file
2674  *
2675  * Allocate and attach a security structure to the file->f_security field.  The
2676  * security field is initialized to NULL when the structure is first created.
2677  *
2678  * Return: Return 0 if the hook is successful and permission is granted.
2679  */
2680 int security_file_alloc(struct file *file)
2681 {
2682 	int rc = lsm_file_alloc(file);
2683 
2684 	if (rc)
2685 		return rc;
2686 	rc = call_int_hook(file_alloc_security, 0, file);
2687 	if (unlikely(rc))
2688 		security_file_free(file);
2689 	return rc;
2690 }
2691 
2692 /**
2693  * security_file_free() - Free a file's LSM blob
2694  * @file: the file
2695  *
2696  * Deallocate and free any security structures stored in file->f_security.
2697  */
2698 void security_file_free(struct file *file)
2699 {
2700 	void *blob;
2701 
2702 	call_void_hook(file_free_security, file);
2703 
2704 	blob = file->f_security;
2705 	if (blob) {
2706 		file->f_security = NULL;
2707 		kmem_cache_free(lsm_file_cache, blob);
2708 	}
2709 }
2710 
2711 /**
2712  * security_file_ioctl() - Check if an ioctl is allowed
2713  * @file: associated file
2714  * @cmd: ioctl cmd
2715  * @arg: ioctl arguments
2716  *
2717  * Check permission for an ioctl operation on @file.  Note that @arg sometimes
2718  * represents a user space pointer; in other cases, it may be a simple integer
2719  * value.  When @arg represents a user space pointer, it should never be used
2720  * by the security module.
2721  *
2722  * Return: Returns 0 if permission is granted.
2723  */
2724 int security_file_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
2725 {
2726 	return call_int_hook(file_ioctl, 0, file, cmd, arg);
2727 }
2728 EXPORT_SYMBOL_GPL(security_file_ioctl);
2729 
2730 /**
2731  * security_file_ioctl_compat() - Check if an ioctl is allowed in compat mode
2732  * @file: associated file
2733  * @cmd: ioctl cmd
2734  * @arg: ioctl arguments
2735  *
2736  * Compat version of security_file_ioctl() that correctly handles 32-bit
2737  * processes running on 64-bit kernels.
2738  *
2739  * Return: Returns 0 if permission is granted.
2740  */
2741 int security_file_ioctl_compat(struct file *file, unsigned int cmd,
2742 			       unsigned long arg)
2743 {
2744 	return call_int_hook(file_ioctl_compat, 0, file, cmd, arg);
2745 }
2746 EXPORT_SYMBOL_GPL(security_file_ioctl_compat);
2747 
2748 static inline unsigned long mmap_prot(struct file *file, unsigned long prot)
2749 {
2750 	/*
2751 	 * Does we have PROT_READ and does the application expect
2752 	 * it to imply PROT_EXEC?  If not, nothing to talk about...
2753 	 */
2754 	if ((prot & (PROT_READ | PROT_EXEC)) != PROT_READ)
2755 		return prot;
2756 	if (!(current->personality & READ_IMPLIES_EXEC))
2757 		return prot;
2758 	/*
2759 	 * if that's an anonymous mapping, let it.
2760 	 */
2761 	if (!file)
2762 		return prot | PROT_EXEC;
2763 	/*
2764 	 * ditto if it's not on noexec mount, except that on !MMU we need
2765 	 * NOMMU_MAP_EXEC (== VM_MAYEXEC) in this case
2766 	 */
2767 	if (!path_noexec(&file->f_path)) {
2768 #ifndef CONFIG_MMU
2769 		if (file->f_op->mmap_capabilities) {
2770 			unsigned caps = file->f_op->mmap_capabilities(file);
2771 			if (!(caps & NOMMU_MAP_EXEC))
2772 				return prot;
2773 		}
2774 #endif
2775 		return prot | PROT_EXEC;
2776 	}
2777 	/* anything on noexec mount won't get PROT_EXEC */
2778 	return prot;
2779 }
2780 
2781 /**
2782  * security_mmap_file() - Check if mmap'ing a file is allowed
2783  * @file: file
2784  * @prot: protection applied by the kernel
2785  * @flags: flags
2786  *
2787  * Check permissions for a mmap operation.  The @file may be NULL, e.g. if
2788  * mapping anonymous memory.
2789  *
2790  * Return: Returns 0 if permission is granted.
2791  */
2792 int security_mmap_file(struct file *file, unsigned long prot,
2793 		       unsigned long flags)
2794 {
2795 	unsigned long prot_adj = mmap_prot(file, prot);
2796 	int ret;
2797 
2798 	ret = call_int_hook(mmap_file, 0, file, prot, prot_adj, flags);
2799 	if (ret)
2800 		return ret;
2801 	return ima_file_mmap(file, prot, prot_adj, flags);
2802 }
2803 
2804 /**
2805  * security_mmap_addr() - Check if mmap'ing an address is allowed
2806  * @addr: address
2807  *
2808  * Check permissions for a mmap operation at @addr.
2809  *
2810  * Return: Returns 0 if permission is granted.
2811  */
2812 int security_mmap_addr(unsigned long addr)
2813 {
2814 	return call_int_hook(mmap_addr, 0, addr);
2815 }
2816 
2817 /**
2818  * security_file_mprotect() - Check if changing memory protections is allowed
2819  * @vma: memory region
2820  * @reqprot: application requested protection
2821  * @prot: protection applied by the kernel
2822  *
2823  * Check permissions before changing memory access permissions.
2824  *
2825  * Return: Returns 0 if permission is granted.
2826  */
2827 int security_file_mprotect(struct vm_area_struct *vma, unsigned long reqprot,
2828 			   unsigned long prot)
2829 {
2830 	int ret;
2831 
2832 	ret = call_int_hook(file_mprotect, 0, vma, reqprot, prot);
2833 	if (ret)
2834 		return ret;
2835 	return ima_file_mprotect(vma, prot);
2836 }
2837 
2838 /**
2839  * security_file_lock() - Check if a file lock is allowed
2840  * @file: file
2841  * @cmd: lock operation (e.g. F_RDLCK, F_WRLCK)
2842  *
2843  * Check permission before performing file locking operations.  Note the hook
2844  * mediates both flock and fcntl style locks.
2845  *
2846  * Return: Returns 0 if permission is granted.
2847  */
2848 int security_file_lock(struct file *file, unsigned int cmd)
2849 {
2850 	return call_int_hook(file_lock, 0, file, cmd);
2851 }
2852 
2853 /**
2854  * security_file_fcntl() - Check if fcntl() op is allowed
2855  * @file: file
2856  * @cmd: fcntl command
2857  * @arg: command argument
2858  *
2859  * Check permission before allowing the file operation specified by @cmd from
2860  * being performed on the file @file.  Note that @arg sometimes represents a
2861  * user space pointer; in other cases, it may be a simple integer value.  When
2862  * @arg represents a user space pointer, it should never be used by the
2863  * security module.
2864  *
2865  * Return: Returns 0 if permission is granted.
2866  */
2867 int security_file_fcntl(struct file *file, unsigned int cmd, unsigned long arg)
2868 {
2869 	return call_int_hook(file_fcntl, 0, file, cmd, arg);
2870 }
2871 
2872 /**
2873  * security_file_set_fowner() - Set the file owner info in the LSM blob
2874  * @file: the file
2875  *
2876  * Save owner security information (typically from current->security) in
2877  * file->f_security for later use by the send_sigiotask hook.
2878  *
2879  * Return: Returns 0 on success.
2880  */
2881 void security_file_set_fowner(struct file *file)
2882 {
2883 	call_void_hook(file_set_fowner, file);
2884 }
2885 
2886 /**
2887  * security_file_send_sigiotask() - Check if sending SIGIO/SIGURG is allowed
2888  * @tsk: target task
2889  * @fown: signal sender
2890  * @sig: signal to be sent, SIGIO is sent if 0
2891  *
2892  * Check permission for the file owner @fown to send SIGIO or SIGURG to the
2893  * process @tsk.  Note that this hook is sometimes called from interrupt.  Note
2894  * that the fown_struct, @fown, is never outside the context of a struct file,
2895  * so the file structure (and associated security information) can always be
2896  * obtained: container_of(fown, struct file, f_owner).
2897  *
2898  * Return: Returns 0 if permission is granted.
2899  */
2900 int security_file_send_sigiotask(struct task_struct *tsk,
2901 				 struct fown_struct *fown, int sig)
2902 {
2903 	return call_int_hook(file_send_sigiotask, 0, tsk, fown, sig);
2904 }
2905 
2906 /**
2907  * security_file_receive() - Check is receiving a file via IPC is allowed
2908  * @file: file being received
2909  *
2910  * This hook allows security modules to control the ability of a process to
2911  * receive an open file descriptor via socket IPC.
2912  *
2913  * Return: Returns 0 if permission is granted.
2914  */
2915 int security_file_receive(struct file *file)
2916 {
2917 	return call_int_hook(file_receive, 0, file);
2918 }
2919 
2920 /**
2921  * security_file_open() - Save open() time state for late use by the LSM
2922  * @file:
2923  *
2924  * Save open-time permission checking state for later use upon file_permission,
2925  * and recheck access if anything has changed since inode_permission.
2926  *
2927  * Return: Returns 0 if permission is granted.
2928  */
2929 int security_file_open(struct file *file)
2930 {
2931 	int ret;
2932 
2933 	ret = call_int_hook(file_open, 0, file);
2934 	if (ret)
2935 		return ret;
2936 
2937 	return fsnotify_open_perm(file);
2938 }
2939 
2940 /**
2941  * security_file_truncate() - Check if truncating a file is allowed
2942  * @file: file
2943  *
2944  * Check permission before truncating a file, i.e. using ftruncate.  Note that
2945  * truncation permission may also be checked based on the path, using the
2946  * @path_truncate hook.
2947  *
2948  * Return: Returns 0 if permission is granted.
2949  */
2950 int security_file_truncate(struct file *file)
2951 {
2952 	return call_int_hook(file_truncate, 0, file);
2953 }
2954 
2955 /**
2956  * security_task_alloc() - Allocate a task's LSM blob
2957  * @task: the task
2958  * @clone_flags: flags indicating what is being shared
2959  *
2960  * Handle allocation of task-related resources.
2961  *
2962  * Return: Returns a zero on success, negative values on failure.
2963  */
2964 int security_task_alloc(struct task_struct *task, unsigned long clone_flags)
2965 {
2966 	int rc = lsm_task_alloc(task);
2967 
2968 	if (rc)
2969 		return rc;
2970 	rc = call_int_hook(task_alloc, 0, task, clone_flags);
2971 	if (unlikely(rc))
2972 		security_task_free(task);
2973 	return rc;
2974 }
2975 
2976 /**
2977  * security_task_free() - Free a task's LSM blob and related resources
2978  * @task: task
2979  *
2980  * Handle release of task-related resources.  Note that this can be called from
2981  * interrupt context.
2982  */
2983 void security_task_free(struct task_struct *task)
2984 {
2985 	call_void_hook(task_free, task);
2986 
2987 	kfree(task->security);
2988 	task->security = NULL;
2989 }
2990 
2991 /**
2992  * security_cred_alloc_blank() - Allocate the min memory to allow cred_transfer
2993  * @cred: credentials
2994  * @gfp: gfp flags
2995  *
2996  * Only allocate sufficient memory and attach to @cred such that
2997  * cred_transfer() will not get ENOMEM.
2998  *
2999  * Return: Returns 0 on success, negative values on failure.
3000  */
3001 int security_cred_alloc_blank(struct cred *cred, gfp_t gfp)
3002 {
3003 	int rc = lsm_cred_alloc(cred, gfp);
3004 
3005 	if (rc)
3006 		return rc;
3007 
3008 	rc = call_int_hook(cred_alloc_blank, 0, cred, gfp);
3009 	if (unlikely(rc))
3010 		security_cred_free(cred);
3011 	return rc;
3012 }
3013 
3014 /**
3015  * security_cred_free() - Free the cred's LSM blob and associated resources
3016  * @cred: credentials
3017  *
3018  * Deallocate and clear the cred->security field in a set of credentials.
3019  */
3020 void security_cred_free(struct cred *cred)
3021 {
3022 	/*
3023 	 * There is a failure case in prepare_creds() that
3024 	 * may result in a call here with ->security being NULL.
3025 	 */
3026 	if (unlikely(cred->security == NULL))
3027 		return;
3028 
3029 	call_void_hook(cred_free, cred);
3030 
3031 	kfree(cred->security);
3032 	cred->security = NULL;
3033 }
3034 
3035 /**
3036  * security_prepare_creds() - Prepare a new set of credentials
3037  * @new: new credentials
3038  * @old: original credentials
3039  * @gfp: gfp flags
3040  *
3041  * Prepare a new set of credentials by copying the data from the old set.
3042  *
3043  * Return: Returns 0 on success, negative values on failure.
3044  */
3045 int security_prepare_creds(struct cred *new, const struct cred *old, gfp_t gfp)
3046 {
3047 	int rc = lsm_cred_alloc(new, gfp);
3048 
3049 	if (rc)
3050 		return rc;
3051 
3052 	rc = call_int_hook(cred_prepare, 0, new, old, gfp);
3053 	if (unlikely(rc))
3054 		security_cred_free(new);
3055 	return rc;
3056 }
3057 
3058 /**
3059  * security_transfer_creds() - Transfer creds
3060  * @new: target credentials
3061  * @old: original credentials
3062  *
3063  * Transfer data from original creds to new creds.
3064  */
3065 void security_transfer_creds(struct cred *new, const struct cred *old)
3066 {
3067 	call_void_hook(cred_transfer, new, old);
3068 }
3069 
3070 /**
3071  * security_cred_getsecid() - Get the secid from a set of credentials
3072  * @c: credentials
3073  * @secid: secid value
3074  *
3075  * Retrieve the security identifier of the cred structure @c.  In case of
3076  * failure, @secid will be set to zero.
3077  */
3078 void security_cred_getsecid(const struct cred *c, u32 *secid)
3079 {
3080 	*secid = 0;
3081 	call_void_hook(cred_getsecid, c, secid);
3082 }
3083 EXPORT_SYMBOL(security_cred_getsecid);
3084 
3085 /**
3086  * security_kernel_act_as() - Set the kernel credentials to act as secid
3087  * @new: credentials
3088  * @secid: secid
3089  *
3090  * Set the credentials for a kernel service to act as (subjective context).
3091  * The current task must be the one that nominated @secid.
3092  *
3093  * Return: Returns 0 if successful.
3094  */
3095 int security_kernel_act_as(struct cred *new, u32 secid)
3096 {
3097 	return call_int_hook(kernel_act_as, 0, new, secid);
3098 }
3099 
3100 /**
3101  * security_kernel_create_files_as() - Set file creation context using an inode
3102  * @new: target credentials
3103  * @inode: reference inode
3104  *
3105  * Set the file creation context in a set of credentials to be the same as the
3106  * objective context of the specified inode.  The current task must be the one
3107  * that nominated @inode.
3108  *
3109  * Return: Returns 0 if successful.
3110  */
3111 int security_kernel_create_files_as(struct cred *new, struct inode *inode)
3112 {
3113 	return call_int_hook(kernel_create_files_as, 0, new, inode);
3114 }
3115 
3116 /**
3117  * security_kernel_module_request() - Check is loading a module is allowed
3118  * @kmod_name: module name
3119  *
3120  * Ability to trigger the kernel to automatically upcall to userspace for
3121  * userspace to load a kernel module with the given name.
3122  *
3123  * Return: Returns 0 if successful.
3124  */
3125 int security_kernel_module_request(char *kmod_name)
3126 {
3127 	int ret;
3128 
3129 	ret = call_int_hook(kernel_module_request, 0, kmod_name);
3130 	if (ret)
3131 		return ret;
3132 	return integrity_kernel_module_request(kmod_name);
3133 }
3134 
3135 /**
3136  * security_kernel_read_file() - Read a file specified by userspace
3137  * @file: file
3138  * @id: file identifier
3139  * @contents: trust if security_kernel_post_read_file() will be called
3140  *
3141  * Read a file specified by userspace.
3142  *
3143  * Return: Returns 0 if permission is granted.
3144  */
3145 int security_kernel_read_file(struct file *file, enum kernel_read_file_id id,
3146 			      bool contents)
3147 {
3148 	int ret;
3149 
3150 	ret = call_int_hook(kernel_read_file, 0, file, id, contents);
3151 	if (ret)
3152 		return ret;
3153 	return ima_read_file(file, id, contents);
3154 }
3155 EXPORT_SYMBOL_GPL(security_kernel_read_file);
3156 
3157 /**
3158  * security_kernel_post_read_file() - Read a file specified by userspace
3159  * @file: file
3160  * @buf: file contents
3161  * @size: size of file contents
3162  * @id: file identifier
3163  *
3164  * Read a file specified by userspace.  This must be paired with a prior call
3165  * to security_kernel_read_file() call that indicated this hook would also be
3166  * called, see security_kernel_read_file() for more information.
3167  *
3168  * Return: Returns 0 if permission is granted.
3169  */
3170 int security_kernel_post_read_file(struct file *file, char *buf, loff_t size,
3171 				   enum kernel_read_file_id id)
3172 {
3173 	int ret;
3174 
3175 	ret = call_int_hook(kernel_post_read_file, 0, file, buf, size, id);
3176 	if (ret)
3177 		return ret;
3178 	return ima_post_read_file(file, buf, size, id);
3179 }
3180 EXPORT_SYMBOL_GPL(security_kernel_post_read_file);
3181 
3182 /**
3183  * security_kernel_load_data() - Load data provided by userspace
3184  * @id: data identifier
3185  * @contents: true if security_kernel_post_load_data() will be called
3186  *
3187  * Load data provided by userspace.
3188  *
3189  * Return: Returns 0 if permission is granted.
3190  */
3191 int security_kernel_load_data(enum kernel_load_data_id id, bool contents)
3192 {
3193 	int ret;
3194 
3195 	ret = call_int_hook(kernel_load_data, 0, id, contents);
3196 	if (ret)
3197 		return ret;
3198 	return ima_load_data(id, contents);
3199 }
3200 EXPORT_SYMBOL_GPL(security_kernel_load_data);
3201 
3202 /**
3203  * security_kernel_post_load_data() - Load userspace data from a non-file source
3204  * @buf: data
3205  * @size: size of data
3206  * @id: data identifier
3207  * @description: text description of data, specific to the id value
3208  *
3209  * Load data provided by a non-file source (usually userspace buffer).  This
3210  * must be paired with a prior security_kernel_load_data() call that indicated
3211  * this hook would also be called, see security_kernel_load_data() for more
3212  * information.
3213  *
3214  * Return: Returns 0 if permission is granted.
3215  */
3216 int security_kernel_post_load_data(char *buf, loff_t size,
3217 				   enum kernel_load_data_id id,
3218 				   char *description)
3219 {
3220 	int ret;
3221 
3222 	ret = call_int_hook(kernel_post_load_data, 0, buf, size, id,
3223 			    description);
3224 	if (ret)
3225 		return ret;
3226 	return ima_post_load_data(buf, size, id, description);
3227 }
3228 EXPORT_SYMBOL_GPL(security_kernel_post_load_data);
3229 
3230 /**
3231  * security_task_fix_setuid() - Update LSM with new user id attributes
3232  * @new: updated credentials
3233  * @old: credentials being replaced
3234  * @flags: LSM_SETID_* flag values
3235  *
3236  * Update the module's state after setting one or more of the user identity
3237  * attributes of the current process.  The @flags parameter indicates which of
3238  * the set*uid system calls invoked this hook.  If @new is the set of
3239  * credentials that will be installed.  Modifications should be made to this
3240  * rather than to @current->cred.
3241  *
3242  * Return: Returns 0 on success.
3243  */
3244 int security_task_fix_setuid(struct cred *new, const struct cred *old,
3245 			     int flags)
3246 {
3247 	return call_int_hook(task_fix_setuid, 0, new, old, flags);
3248 }
3249 
3250 /**
3251  * security_task_fix_setgid() - Update LSM with new group id attributes
3252  * @new: updated credentials
3253  * @old: credentials being replaced
3254  * @flags: LSM_SETID_* flag value
3255  *
3256  * Update the module's state after setting one or more of the group identity
3257  * attributes of the current process.  The @flags parameter indicates which of
3258  * the set*gid system calls invoked this hook.  @new is the set of credentials
3259  * that will be installed.  Modifications should be made to this rather than to
3260  * @current->cred.
3261  *
3262  * Return: Returns 0 on success.
3263  */
3264 int security_task_fix_setgid(struct cred *new, const struct cred *old,
3265 			     int flags)
3266 {
3267 	return call_int_hook(task_fix_setgid, 0, new, old, flags);
3268 }
3269 
3270 /**
3271  * security_task_fix_setgroups() - Update LSM with new supplementary groups
3272  * @new: updated credentials
3273  * @old: credentials being replaced
3274  *
3275  * Update the module's state after setting the supplementary group identity
3276  * attributes of the current process.  @new is the set of credentials that will
3277  * be installed.  Modifications should be made to this rather than to
3278  * @current->cred.
3279  *
3280  * Return: Returns 0 on success.
3281  */
3282 int security_task_fix_setgroups(struct cred *new, const struct cred *old)
3283 {
3284 	return call_int_hook(task_fix_setgroups, 0, new, old);
3285 }
3286 
3287 /**
3288  * security_task_setpgid() - Check if setting the pgid is allowed
3289  * @p: task being modified
3290  * @pgid: new pgid
3291  *
3292  * Check permission before setting the process group identifier of the process
3293  * @p to @pgid.
3294  *
3295  * Return: Returns 0 if permission is granted.
3296  */
3297 int security_task_setpgid(struct task_struct *p, pid_t pgid)
3298 {
3299 	return call_int_hook(task_setpgid, 0, p, pgid);
3300 }
3301 
3302 /**
3303  * security_task_getpgid() - Check if getting the pgid is allowed
3304  * @p: task
3305  *
3306  * Check permission before getting the process group identifier of the process
3307  * @p.
3308  *
3309  * Return: Returns 0 if permission is granted.
3310  */
3311 int security_task_getpgid(struct task_struct *p)
3312 {
3313 	return call_int_hook(task_getpgid, 0, p);
3314 }
3315 
3316 /**
3317  * security_task_getsid() - Check if getting the session id is allowed
3318  * @p: task
3319  *
3320  * Check permission before getting the session identifier of the process @p.
3321  *
3322  * Return: Returns 0 if permission is granted.
3323  */
3324 int security_task_getsid(struct task_struct *p)
3325 {
3326 	return call_int_hook(task_getsid, 0, p);
3327 }
3328 
3329 /**
3330  * security_current_getsecid_subj() - Get the current task's subjective secid
3331  * @secid: secid value
3332  *
3333  * Retrieve the subjective security identifier of the current task and return
3334  * it in @secid.  In case of failure, @secid will be set to zero.
3335  */
3336 void security_current_getsecid_subj(u32 *secid)
3337 {
3338 	*secid = 0;
3339 	call_void_hook(current_getsecid_subj, secid);
3340 }
3341 EXPORT_SYMBOL(security_current_getsecid_subj);
3342 
3343 /**
3344  * security_task_getsecid_obj() - Get a task's objective secid
3345  * @p: target task
3346  * @secid: secid value
3347  *
3348  * Retrieve the objective security identifier of the task_struct in @p and
3349  * return it in @secid. In case of failure, @secid will be set to zero.
3350  */
3351 void security_task_getsecid_obj(struct task_struct *p, u32 *secid)
3352 {
3353 	*secid = 0;
3354 	call_void_hook(task_getsecid_obj, p, secid);
3355 }
3356 EXPORT_SYMBOL(security_task_getsecid_obj);
3357 
3358 /**
3359  * security_task_setnice() - Check if setting a task's nice value is allowed
3360  * @p: target task
3361  * @nice: nice value
3362  *
3363  * Check permission before setting the nice value of @p to @nice.
3364  *
3365  * Return: Returns 0 if permission is granted.
3366  */
3367 int security_task_setnice(struct task_struct *p, int nice)
3368 {
3369 	return call_int_hook(task_setnice, 0, p, nice);
3370 }
3371 
3372 /**
3373  * security_task_setioprio() - Check if setting a task's ioprio is allowed
3374  * @p: target task
3375  * @ioprio: ioprio value
3376  *
3377  * Check permission before setting the ioprio value of @p to @ioprio.
3378  *
3379  * Return: Returns 0 if permission is granted.
3380  */
3381 int security_task_setioprio(struct task_struct *p, int ioprio)
3382 {
3383 	return call_int_hook(task_setioprio, 0, p, ioprio);
3384 }
3385 
3386 /**
3387  * security_task_getioprio() - Check if getting a task's ioprio is allowed
3388  * @p: task
3389  *
3390  * Check permission before getting the ioprio value of @p.
3391  *
3392  * Return: Returns 0 if permission is granted.
3393  */
3394 int security_task_getioprio(struct task_struct *p)
3395 {
3396 	return call_int_hook(task_getioprio, 0, p);
3397 }
3398 
3399 /**
3400  * security_task_prlimit() - Check if get/setting resources limits is allowed
3401  * @cred: current task credentials
3402  * @tcred: target task credentials
3403  * @flags: LSM_PRLIMIT_* flag bits indicating a get/set/both
3404  *
3405  * Check permission before getting and/or setting the resource limits of
3406  * another task.
3407  *
3408  * Return: Returns 0 if permission is granted.
3409  */
3410 int security_task_prlimit(const struct cred *cred, const struct cred *tcred,
3411 			  unsigned int flags)
3412 {
3413 	return call_int_hook(task_prlimit, 0, cred, tcred, flags);
3414 }
3415 
3416 /**
3417  * security_task_setrlimit() - Check if setting a new rlimit value is allowed
3418  * @p: target task's group leader
3419  * @resource: resource whose limit is being set
3420  * @new_rlim: new resource limit
3421  *
3422  * Check permission before setting the resource limits of process @p for
3423  * @resource to @new_rlim.  The old resource limit values can be examined by
3424  * dereferencing (p->signal->rlim + resource).
3425  *
3426  * Return: Returns 0 if permission is granted.
3427  */
3428 int security_task_setrlimit(struct task_struct *p, unsigned int resource,
3429 			    struct rlimit *new_rlim)
3430 {
3431 	return call_int_hook(task_setrlimit, 0, p, resource, new_rlim);
3432 }
3433 
3434 /**
3435  * security_task_setscheduler() - Check if setting sched policy/param is allowed
3436  * @p: target task
3437  *
3438  * Check permission before setting scheduling policy and/or parameters of
3439  * process @p.
3440  *
3441  * Return: Returns 0 if permission is granted.
3442  */
3443 int security_task_setscheduler(struct task_struct *p)
3444 {
3445 	return call_int_hook(task_setscheduler, 0, p);
3446 }
3447 
3448 /**
3449  * security_task_getscheduler() - Check if getting scheduling info is allowed
3450  * @p: target task
3451  *
3452  * Check permission before obtaining scheduling information for process @p.
3453  *
3454  * Return: Returns 0 if permission is granted.
3455  */
3456 int security_task_getscheduler(struct task_struct *p)
3457 {
3458 	return call_int_hook(task_getscheduler, 0, p);
3459 }
3460 
3461 /**
3462  * security_task_movememory() - Check if moving memory is allowed
3463  * @p: task
3464  *
3465  * Check permission before moving memory owned by process @p.
3466  *
3467  * Return: Returns 0 if permission is granted.
3468  */
3469 int security_task_movememory(struct task_struct *p)
3470 {
3471 	return call_int_hook(task_movememory, 0, p);
3472 }
3473 
3474 /**
3475  * security_task_kill() - Check if sending a signal is allowed
3476  * @p: target process
3477  * @info: signal information
3478  * @sig: signal value
3479  * @cred: credentials of the signal sender, NULL if @current
3480  *
3481  * Check permission before sending signal @sig to @p.  @info can be NULL, the
3482  * constant 1, or a pointer to a kernel_siginfo structure.  If @info is 1 or
3483  * SI_FROMKERNEL(info) is true, then the signal should be viewed as coming from
3484  * the kernel and should typically be permitted.  SIGIO signals are handled
3485  * separately by the send_sigiotask hook in file_security_ops.
3486  *
3487  * Return: Returns 0 if permission is granted.
3488  */
3489 int security_task_kill(struct task_struct *p, struct kernel_siginfo *info,
3490 		       int sig, const struct cred *cred)
3491 {
3492 	return call_int_hook(task_kill, 0, p, info, sig, cred);
3493 }
3494 
3495 /**
3496  * security_task_prctl() - Check if a prctl op is allowed
3497  * @option: operation
3498  * @arg2: argument
3499  * @arg3: argument
3500  * @arg4: argument
3501  * @arg5: argument
3502  *
3503  * Check permission before performing a process control operation on the
3504  * current process.
3505  *
3506  * Return: Return -ENOSYS if no-one wanted to handle this op, any other value
3507  *         to cause prctl() to return immediately with that value.
3508  */
3509 int security_task_prctl(int option, unsigned long arg2, unsigned long arg3,
3510 			unsigned long arg4, unsigned long arg5)
3511 {
3512 	int thisrc;
3513 	int rc = LSM_RET_DEFAULT(task_prctl);
3514 	struct security_hook_list *hp;
3515 
3516 	hlist_for_each_entry(hp, &security_hook_heads.task_prctl, list) {
3517 		thisrc = hp->hook.task_prctl(option, arg2, arg3, arg4, arg5);
3518 		if (thisrc != LSM_RET_DEFAULT(task_prctl)) {
3519 			rc = thisrc;
3520 			if (thisrc != 0)
3521 				break;
3522 		}
3523 	}
3524 	return rc;
3525 }
3526 
3527 /**
3528  * security_task_to_inode() - Set the security attributes of a task's inode
3529  * @p: task
3530  * @inode: inode
3531  *
3532  * Set the security attributes for an inode based on an associated task's
3533  * security attributes, e.g. for /proc/pid inodes.
3534  */
3535 void security_task_to_inode(struct task_struct *p, struct inode *inode)
3536 {
3537 	call_void_hook(task_to_inode, p, inode);
3538 }
3539 
3540 /**
3541  * security_create_user_ns() - Check if creating a new userns is allowed
3542  * @cred: prepared creds
3543  *
3544  * Check permission prior to creating a new user namespace.
3545  *
3546  * Return: Returns 0 if successful, otherwise < 0 error code.
3547  */
3548 int security_create_user_ns(const struct cred *cred)
3549 {
3550 	return call_int_hook(userns_create, 0, cred);
3551 }
3552 
3553 /**
3554  * security_ipc_permission() - Check if sysv ipc access is allowed
3555  * @ipcp: ipc permission structure
3556  * @flag: requested permissions
3557  *
3558  * Check permissions for access to IPC.
3559  *
3560  * Return: Returns 0 if permission is granted.
3561  */
3562 int security_ipc_permission(struct kern_ipc_perm *ipcp, short flag)
3563 {
3564 	return call_int_hook(ipc_permission, 0, ipcp, flag);
3565 }
3566 
3567 /**
3568  * security_ipc_getsecid() - Get the sysv ipc object's secid
3569  * @ipcp: ipc permission structure
3570  * @secid: secid pointer
3571  *
3572  * Get the secid associated with the ipc object.  In case of failure, @secid
3573  * will be set to zero.
3574  */
3575 void security_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid)
3576 {
3577 	*secid = 0;
3578 	call_void_hook(ipc_getsecid, ipcp, secid);
3579 }
3580 
3581 /**
3582  * security_msg_msg_alloc() - Allocate a sysv ipc message LSM blob
3583  * @msg: message structure
3584  *
3585  * Allocate and attach a security structure to the msg->security field.  The
3586  * security field is initialized to NULL when the structure is first created.
3587  *
3588  * Return: Return 0 if operation was successful and permission is granted.
3589  */
3590 int security_msg_msg_alloc(struct msg_msg *msg)
3591 {
3592 	int rc = lsm_msg_msg_alloc(msg);
3593 
3594 	if (unlikely(rc))
3595 		return rc;
3596 	rc = call_int_hook(msg_msg_alloc_security, 0, msg);
3597 	if (unlikely(rc))
3598 		security_msg_msg_free(msg);
3599 	return rc;
3600 }
3601 
3602 /**
3603  * security_msg_msg_free() - Free a sysv ipc message LSM blob
3604  * @msg: message structure
3605  *
3606  * Deallocate the security structure for this message.
3607  */
3608 void security_msg_msg_free(struct msg_msg *msg)
3609 {
3610 	call_void_hook(msg_msg_free_security, msg);
3611 	kfree(msg->security);
3612 	msg->security = NULL;
3613 }
3614 
3615 /**
3616  * security_msg_queue_alloc() - Allocate a sysv ipc msg queue LSM blob
3617  * @msq: sysv ipc permission structure
3618  *
3619  * Allocate and attach a security structure to @msg. The security field is
3620  * initialized to NULL when the structure is first created.
3621  *
3622  * Return: Returns 0 if operation was successful and permission is granted.
3623  */
3624 int security_msg_queue_alloc(struct kern_ipc_perm *msq)
3625 {
3626 	int rc = lsm_ipc_alloc(msq);
3627 
3628 	if (unlikely(rc))
3629 		return rc;
3630 	rc = call_int_hook(msg_queue_alloc_security, 0, msq);
3631 	if (unlikely(rc))
3632 		security_msg_queue_free(msq);
3633 	return rc;
3634 }
3635 
3636 /**
3637  * security_msg_queue_free() - Free a sysv ipc msg queue LSM blob
3638  * @msq: sysv ipc permission structure
3639  *
3640  * Deallocate security field @perm->security for the message queue.
3641  */
3642 void security_msg_queue_free(struct kern_ipc_perm *msq)
3643 {
3644 	call_void_hook(msg_queue_free_security, msq);
3645 	kfree(msq->security);
3646 	msq->security = NULL;
3647 }
3648 
3649 /**
3650  * security_msg_queue_associate() - Check if a msg queue operation is allowed
3651  * @msq: sysv ipc permission structure
3652  * @msqflg: operation flags
3653  *
3654  * Check permission when a message queue is requested through the msgget system
3655  * call. This hook is only called when returning the message queue identifier
3656  * for an existing message queue, not when a new message queue is created.
3657  *
3658  * Return: Return 0 if permission is granted.
3659  */
3660 int security_msg_queue_associate(struct kern_ipc_perm *msq, int msqflg)
3661 {
3662 	return call_int_hook(msg_queue_associate, 0, msq, msqflg);
3663 }
3664 
3665 /**
3666  * security_msg_queue_msgctl() - Check if a msg queue operation is allowed
3667  * @msq: sysv ipc permission structure
3668  * @cmd: operation
3669  *
3670  * Check permission when a message control operation specified by @cmd is to be
3671  * performed on the message queue with permissions.
3672  *
3673  * Return: Returns 0 if permission is granted.
3674  */
3675 int security_msg_queue_msgctl(struct kern_ipc_perm *msq, int cmd)
3676 {
3677 	return call_int_hook(msg_queue_msgctl, 0, msq, cmd);
3678 }
3679 
3680 /**
3681  * security_msg_queue_msgsnd() - Check if sending a sysv ipc message is allowed
3682  * @msq: sysv ipc permission structure
3683  * @msg: message
3684  * @msqflg: operation flags
3685  *
3686  * Check permission before a message, @msg, is enqueued on the message queue
3687  * with permissions specified in @msq.
3688  *
3689  * Return: Returns 0 if permission is granted.
3690  */
3691 int security_msg_queue_msgsnd(struct kern_ipc_perm *msq,
3692 			      struct msg_msg *msg, int msqflg)
3693 {
3694 	return call_int_hook(msg_queue_msgsnd, 0, msq, msg, msqflg);
3695 }
3696 
3697 /**
3698  * security_msg_queue_msgrcv() - Check if receiving a sysv ipc msg is allowed
3699  * @msq: sysv ipc permission structure
3700  * @msg: message
3701  * @target: target task
3702  * @type: type of message requested
3703  * @mode: operation flags
3704  *
3705  * Check permission before a message, @msg, is removed from the message	queue.
3706  * The @target task structure contains a pointer to the process that will be
3707  * receiving the message (not equal to the current process when inline receives
3708  * are being performed).
3709  *
3710  * Return: Returns 0 if permission is granted.
3711  */
3712 int security_msg_queue_msgrcv(struct kern_ipc_perm *msq, struct msg_msg *msg,
3713 			      struct task_struct *target, long type, int mode)
3714 {
3715 	return call_int_hook(msg_queue_msgrcv, 0, msq, msg, target, type, mode);
3716 }
3717 
3718 /**
3719  * security_shm_alloc() - Allocate a sysv shm LSM blob
3720  * @shp: sysv ipc permission structure
3721  *
3722  * Allocate and attach a security structure to the @shp security field.  The
3723  * security field is initialized to NULL when the structure is first created.
3724  *
3725  * Return: Returns 0 if operation was successful and permission is granted.
3726  */
3727 int security_shm_alloc(struct kern_ipc_perm *shp)
3728 {
3729 	int rc = lsm_ipc_alloc(shp);
3730 
3731 	if (unlikely(rc))
3732 		return rc;
3733 	rc = call_int_hook(shm_alloc_security, 0, shp);
3734 	if (unlikely(rc))
3735 		security_shm_free(shp);
3736 	return rc;
3737 }
3738 
3739 /**
3740  * security_shm_free() - Free a sysv shm LSM blob
3741  * @shp: sysv ipc permission structure
3742  *
3743  * Deallocate the security structure @perm->security for the memory segment.
3744  */
3745 void security_shm_free(struct kern_ipc_perm *shp)
3746 {
3747 	call_void_hook(shm_free_security, shp);
3748 	kfree(shp->security);
3749 	shp->security = NULL;
3750 }
3751 
3752 /**
3753  * security_shm_associate() - Check if a sysv shm operation is allowed
3754  * @shp: sysv ipc permission structure
3755  * @shmflg: operation flags
3756  *
3757  * Check permission when a shared memory region is requested through the shmget
3758  * system call. This hook is only called when returning the shared memory
3759  * region identifier for an existing region, not when a new shared memory
3760  * region is created.
3761  *
3762  * Return: Returns 0 if permission is granted.
3763  */
3764 int security_shm_associate(struct kern_ipc_perm *shp, int shmflg)
3765 {
3766 	return call_int_hook(shm_associate, 0, shp, shmflg);
3767 }
3768 
3769 /**
3770  * security_shm_shmctl() - Check if a sysv shm operation is allowed
3771  * @shp: sysv ipc permission structure
3772  * @cmd: operation
3773  *
3774  * Check permission when a shared memory control operation specified by @cmd is
3775  * to be performed on the shared memory region with permissions in @shp.
3776  *
3777  * Return: Return 0 if permission is granted.
3778  */
3779 int security_shm_shmctl(struct kern_ipc_perm *shp, int cmd)
3780 {
3781 	return call_int_hook(shm_shmctl, 0, shp, cmd);
3782 }
3783 
3784 /**
3785  * security_shm_shmat() - Check if a sysv shm attach operation is allowed
3786  * @shp: sysv ipc permission structure
3787  * @shmaddr: address of memory region to attach
3788  * @shmflg: operation flags
3789  *
3790  * Check permissions prior to allowing the shmat system call to attach the
3791  * shared memory segment with permissions @shp to the data segment of the
3792  * calling process. The attaching address is specified by @shmaddr.
3793  *
3794  * Return: Returns 0 if permission is granted.
3795  */
3796 int security_shm_shmat(struct kern_ipc_perm *shp,
3797 		       char __user *shmaddr, int shmflg)
3798 {
3799 	return call_int_hook(shm_shmat, 0, shp, shmaddr, shmflg);
3800 }
3801 
3802 /**
3803  * security_sem_alloc() - Allocate a sysv semaphore LSM blob
3804  * @sma: sysv ipc permission structure
3805  *
3806  * Allocate and attach a security structure to the @sma security field. The
3807  * security field is initialized to NULL when the structure is first created.
3808  *
3809  * Return: Returns 0 if operation was successful and permission is granted.
3810  */
3811 int security_sem_alloc(struct kern_ipc_perm *sma)
3812 {
3813 	int rc = lsm_ipc_alloc(sma);
3814 
3815 	if (unlikely(rc))
3816 		return rc;
3817 	rc = call_int_hook(sem_alloc_security, 0, sma);
3818 	if (unlikely(rc))
3819 		security_sem_free(sma);
3820 	return rc;
3821 }
3822 
3823 /**
3824  * security_sem_free() - Free a sysv semaphore LSM blob
3825  * @sma: sysv ipc permission structure
3826  *
3827  * Deallocate security structure @sma->security for the semaphore.
3828  */
3829 void security_sem_free(struct kern_ipc_perm *sma)
3830 {
3831 	call_void_hook(sem_free_security, sma);
3832 	kfree(sma->security);
3833 	sma->security = NULL;
3834 }
3835 
3836 /**
3837  * security_sem_associate() - Check if a sysv semaphore operation is allowed
3838  * @sma: sysv ipc permission structure
3839  * @semflg: operation flags
3840  *
3841  * Check permission when a semaphore is requested through the semget system
3842  * call. This hook is only called when returning the semaphore identifier for
3843  * an existing semaphore, not when a new one must be created.
3844  *
3845  * Return: Returns 0 if permission is granted.
3846  */
3847 int security_sem_associate(struct kern_ipc_perm *sma, int semflg)
3848 {
3849 	return call_int_hook(sem_associate, 0, sma, semflg);
3850 }
3851 
3852 /**
3853  * security_sem_semctl() - Check if a sysv semaphore operation is allowed
3854  * @sma: sysv ipc permission structure
3855  * @cmd: operation
3856  *
3857  * Check permission when a semaphore operation specified by @cmd is to be
3858  * performed on the semaphore.
3859  *
3860  * Return: Returns 0 if permission is granted.
3861  */
3862 int security_sem_semctl(struct kern_ipc_perm *sma, int cmd)
3863 {
3864 	return call_int_hook(sem_semctl, 0, sma, cmd);
3865 }
3866 
3867 /**
3868  * security_sem_semop() - Check if a sysv semaphore operation is allowed
3869  * @sma: sysv ipc permission structure
3870  * @sops: operations to perform
3871  * @nsops: number of operations
3872  * @alter: flag indicating changes will be made
3873  *
3874  * Check permissions before performing operations on members of the semaphore
3875  * set. If the @alter flag is nonzero, the semaphore set may be modified.
3876  *
3877  * Return: Returns 0 if permission is granted.
3878  */
3879 int security_sem_semop(struct kern_ipc_perm *sma, struct sembuf *sops,
3880 		       unsigned nsops, int alter)
3881 {
3882 	return call_int_hook(sem_semop, 0, sma, sops, nsops, alter);
3883 }
3884 
3885 /**
3886  * security_d_instantiate() - Populate an inode's LSM state based on a dentry
3887  * @dentry: dentry
3888  * @inode: inode
3889  *
3890  * Fill in @inode security information for a @dentry if allowed.
3891  */
3892 void security_d_instantiate(struct dentry *dentry, struct inode *inode)
3893 {
3894 	if (unlikely(inode && IS_PRIVATE(inode)))
3895 		return;
3896 	call_void_hook(d_instantiate, dentry, inode);
3897 }
3898 EXPORT_SYMBOL(security_d_instantiate);
3899 
3900 /*
3901  * Please keep this in sync with it's counterpart in security/lsm_syscalls.c
3902  */
3903 
3904 /**
3905  * security_getselfattr - Read an LSM attribute of the current process.
3906  * @attr: which attribute to return
3907  * @uctx: the user-space destination for the information, or NULL
3908  * @size: pointer to the size of space available to receive the data
3909  * @flags: special handling options. LSM_FLAG_SINGLE indicates that only
3910  * attributes associated with the LSM identified in the passed @ctx be
3911  * reported.
3912  *
3913  * A NULL value for @uctx can be used to get both the number of attributes
3914  * and the size of the data.
3915  *
3916  * Returns the number of attributes found on success, negative value
3917  * on error. @size is reset to the total size of the data.
3918  * If @size is insufficient to contain the data -E2BIG is returned.
3919  */
3920 int security_getselfattr(unsigned int attr, struct lsm_ctx __user *uctx,
3921 			 size_t __user *size, u32 flags)
3922 {
3923 	struct security_hook_list *hp;
3924 	struct lsm_ctx lctx = { .id = LSM_ID_UNDEF, };
3925 	u8 __user *base = (u8 __user *)uctx;
3926 	size_t total = 0;
3927 	size_t entrysize;
3928 	size_t left;
3929 	bool toobig = false;
3930 	bool single = false;
3931 	int count = 0;
3932 	int rc;
3933 
3934 	if (attr == LSM_ATTR_UNDEF)
3935 		return -EINVAL;
3936 	if (size == NULL)
3937 		return -EINVAL;
3938 	if (get_user(left, size))
3939 		return -EFAULT;
3940 
3941 	if (flags) {
3942 		/*
3943 		 * Only flag supported is LSM_FLAG_SINGLE
3944 		 */
3945 		if (flags != LSM_FLAG_SINGLE || !uctx)
3946 			return -EINVAL;
3947 		if (copy_from_user(&lctx, uctx, sizeof(lctx)))
3948 			return -EFAULT;
3949 		/*
3950 		 * If the LSM ID isn't specified it is an error.
3951 		 */
3952 		if (lctx.id == LSM_ID_UNDEF)
3953 			return -EINVAL;
3954 		single = true;
3955 	}
3956 
3957 	/*
3958 	 * In the usual case gather all the data from the LSMs.
3959 	 * In the single case only get the data from the LSM specified.
3960 	 */
3961 	hlist_for_each_entry(hp, &security_hook_heads.getselfattr, list) {
3962 		if (single && lctx.id != hp->lsmid->id)
3963 			continue;
3964 		entrysize = left;
3965 		if (base)
3966 			uctx = (struct lsm_ctx __user *)(base + total);
3967 		rc = hp->hook.getselfattr(attr, uctx, &entrysize, flags);
3968 		if (rc == -EOPNOTSUPP) {
3969 			rc = 0;
3970 			continue;
3971 		}
3972 		if (rc == -E2BIG) {
3973 			rc = 0;
3974 			left = 0;
3975 			toobig = true;
3976 		} else if (rc < 0)
3977 			return rc;
3978 		else
3979 			left -= entrysize;
3980 
3981 		total += entrysize;
3982 		count += rc;
3983 		if (single)
3984 			break;
3985 	}
3986 	if (put_user(total, size))
3987 		return -EFAULT;
3988 	if (toobig)
3989 		return -E2BIG;
3990 	if (count == 0)
3991 		return LSM_RET_DEFAULT(getselfattr);
3992 	return count;
3993 }
3994 
3995 /*
3996  * Please keep this in sync with it's counterpart in security/lsm_syscalls.c
3997  */
3998 
3999 /**
4000  * security_setselfattr - Set an LSM attribute on the current process.
4001  * @attr: which attribute to set
4002  * @uctx: the user-space source for the information
4003  * @size: the size of the data
4004  * @flags: reserved for future use, must be 0
4005  *
4006  * Set an LSM attribute for the current process. The LSM, attribute
4007  * and new value are included in @uctx.
4008  *
4009  * Returns 0 on success, -EINVAL if the input is inconsistent, -EFAULT
4010  * if the user buffer is inaccessible, E2BIG if size is too big, or an
4011  * LSM specific failure.
4012  */
4013 int security_setselfattr(unsigned int attr, struct lsm_ctx __user *uctx,
4014 			 size_t size, u32 flags)
4015 {
4016 	struct security_hook_list *hp;
4017 	struct lsm_ctx *lctx;
4018 	int rc = LSM_RET_DEFAULT(setselfattr);
4019 	u64 required_len;
4020 
4021 	if (flags)
4022 		return -EINVAL;
4023 	if (size < sizeof(*lctx))
4024 		return -EINVAL;
4025 	if (size > PAGE_SIZE)
4026 		return -E2BIG;
4027 
4028 	lctx = memdup_user(uctx, size);
4029 	if (IS_ERR(lctx))
4030 		return PTR_ERR(lctx);
4031 
4032 	if (size < lctx->len ||
4033 	    check_add_overflow(sizeof(*lctx), lctx->ctx_len, &required_len) ||
4034 	    lctx->len < required_len) {
4035 		rc = -EINVAL;
4036 		goto free_out;
4037 	}
4038 
4039 	hlist_for_each_entry(hp, &security_hook_heads.setselfattr, list)
4040 		if ((hp->lsmid->id) == lctx->id) {
4041 			rc = hp->hook.setselfattr(attr, lctx, size, flags);
4042 			break;
4043 		}
4044 
4045 free_out:
4046 	kfree(lctx);
4047 	return rc;
4048 }
4049 
4050 /**
4051  * security_getprocattr() - Read an attribute for a task
4052  * @p: the task
4053  * @lsmid: LSM identification
4054  * @name: attribute name
4055  * @value: attribute value
4056  *
4057  * Read attribute @name for task @p and store it into @value if allowed.
4058  *
4059  * Return: Returns the length of @value on success, a negative value otherwise.
4060  */
4061 int security_getprocattr(struct task_struct *p, int lsmid, const char *name,
4062 			 char **value)
4063 {
4064 	struct security_hook_list *hp;
4065 
4066 	hlist_for_each_entry(hp, &security_hook_heads.getprocattr, list) {
4067 		if (lsmid != 0 && lsmid != hp->lsmid->id)
4068 			continue;
4069 		return hp->hook.getprocattr(p, name, value);
4070 	}
4071 	return LSM_RET_DEFAULT(getprocattr);
4072 }
4073 
4074 /**
4075  * security_setprocattr() - Set an attribute for a task
4076  * @lsmid: LSM identification
4077  * @name: attribute name
4078  * @value: attribute value
4079  * @size: attribute value size
4080  *
4081  * Write (set) the current task's attribute @name to @value, size @size if
4082  * allowed.
4083  *
4084  * Return: Returns bytes written on success, a negative value otherwise.
4085  */
4086 int security_setprocattr(int lsmid, const char *name, void *value, size_t size)
4087 {
4088 	struct security_hook_list *hp;
4089 
4090 	hlist_for_each_entry(hp, &security_hook_heads.setprocattr, list) {
4091 		if (lsmid != 0 && lsmid != hp->lsmid->id)
4092 			continue;
4093 		return hp->hook.setprocattr(name, value, size);
4094 	}
4095 	return LSM_RET_DEFAULT(setprocattr);
4096 }
4097 
4098 /**
4099  * security_netlink_send() - Save info and check if netlink sending is allowed
4100  * @sk: sending socket
4101  * @skb: netlink message
4102  *
4103  * Save security information for a netlink message so that permission checking
4104  * can be performed when the message is processed.  The security information
4105  * can be saved using the eff_cap field of the netlink_skb_parms structure.
4106  * Also may be used to provide fine grained control over message transmission.
4107  *
4108  * Return: Returns 0 if the information was successfully saved and message is
4109  *         allowed to be transmitted.
4110  */
4111 int security_netlink_send(struct sock *sk, struct sk_buff *skb)
4112 {
4113 	return call_int_hook(netlink_send, 0, sk, skb);
4114 }
4115 
4116 /**
4117  * security_ismaclabel() - Check is the named attribute is a MAC label
4118  * @name: full extended attribute name
4119  *
4120  * Check if the extended attribute specified by @name represents a MAC label.
4121  *
4122  * Return: Returns 1 if name is a MAC attribute otherwise returns 0.
4123  */
4124 int security_ismaclabel(const char *name)
4125 {
4126 	return call_int_hook(ismaclabel, 0, name);
4127 }
4128 EXPORT_SYMBOL(security_ismaclabel);
4129 
4130 /**
4131  * security_secid_to_secctx() - Convert a secid to a secctx
4132  * @secid: secid
4133  * @secdata: secctx
4134  * @seclen: secctx length
4135  *
4136  * Convert secid to security context.  If @secdata is NULL the length of the
4137  * result will be returned in @seclen, but no @secdata will be returned.  This
4138  * does mean that the length could change between calls to check the length and
4139  * the next call which actually allocates and returns the @secdata.
4140  *
4141  * Return: Return 0 on success, error on failure.
4142  */
4143 int security_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
4144 {
4145 	struct security_hook_list *hp;
4146 	int rc;
4147 
4148 	/*
4149 	 * Currently, only one LSM can implement secid_to_secctx (i.e this
4150 	 * LSM hook is not "stackable").
4151 	 */
4152 	hlist_for_each_entry(hp, &security_hook_heads.secid_to_secctx, list) {
4153 		rc = hp->hook.secid_to_secctx(secid, secdata, seclen);
4154 		if (rc != LSM_RET_DEFAULT(secid_to_secctx))
4155 			return rc;
4156 	}
4157 
4158 	return LSM_RET_DEFAULT(secid_to_secctx);
4159 }
4160 EXPORT_SYMBOL(security_secid_to_secctx);
4161 
4162 /**
4163  * security_secctx_to_secid() - Convert a secctx to a secid
4164  * @secdata: secctx
4165  * @seclen: length of secctx
4166  * @secid: secid
4167  *
4168  * Convert security context to secid.
4169  *
4170  * Return: Returns 0 on success, error on failure.
4171  */
4172 int security_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
4173 {
4174 	*secid = 0;
4175 	return call_int_hook(secctx_to_secid, 0, secdata, seclen, secid);
4176 }
4177 EXPORT_SYMBOL(security_secctx_to_secid);
4178 
4179 /**
4180  * security_release_secctx() - Free a secctx buffer
4181  * @secdata: secctx
4182  * @seclen: length of secctx
4183  *
4184  * Release the security context.
4185  */
4186 void security_release_secctx(char *secdata, u32 seclen)
4187 {
4188 	call_void_hook(release_secctx, secdata, seclen);
4189 }
4190 EXPORT_SYMBOL(security_release_secctx);
4191 
4192 /**
4193  * security_inode_invalidate_secctx() - Invalidate an inode's security label
4194  * @inode: inode
4195  *
4196  * Notify the security module that it must revalidate the security context of
4197  * an inode.
4198  */
4199 void security_inode_invalidate_secctx(struct inode *inode)
4200 {
4201 	call_void_hook(inode_invalidate_secctx, inode);
4202 }
4203 EXPORT_SYMBOL(security_inode_invalidate_secctx);
4204 
4205 /**
4206  * security_inode_notifysecctx() - Notify the LSM of an inode's security label
4207  * @inode: inode
4208  * @ctx: secctx
4209  * @ctxlen: length of secctx
4210  *
4211  * Notify the security module of what the security context of an inode should
4212  * be.  Initializes the incore security context managed by the security module
4213  * for this inode.  Example usage: NFS client invokes this hook to initialize
4214  * the security context in its incore inode to the value provided by the server
4215  * for the file when the server returned the file's attributes to the client.
4216  * Must be called with inode->i_mutex locked.
4217  *
4218  * Return: Returns 0 on success, error on failure.
4219  */
4220 int security_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen)
4221 {
4222 	return call_int_hook(inode_notifysecctx, 0, inode, ctx, ctxlen);
4223 }
4224 EXPORT_SYMBOL(security_inode_notifysecctx);
4225 
4226 /**
4227  * security_inode_setsecctx() - Change the security label of an inode
4228  * @dentry: inode
4229  * @ctx: secctx
4230  * @ctxlen: length of secctx
4231  *
4232  * Change the security context of an inode.  Updates the incore security
4233  * context managed by the security module and invokes the fs code as needed
4234  * (via __vfs_setxattr_noperm) to update any backing xattrs that represent the
4235  * context.  Example usage: NFS server invokes this hook to change the security
4236  * context in its incore inode and on the backing filesystem to a value
4237  * provided by the client on a SETATTR operation.  Must be called with
4238  * inode->i_mutex locked.
4239  *
4240  * Return: Returns 0 on success, error on failure.
4241  */
4242 int security_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen)
4243 {
4244 	return call_int_hook(inode_setsecctx, 0, dentry, ctx, ctxlen);
4245 }
4246 EXPORT_SYMBOL(security_inode_setsecctx);
4247 
4248 /**
4249  * security_inode_getsecctx() - Get the security label of an inode
4250  * @inode: inode
4251  * @ctx: secctx
4252  * @ctxlen: length of secctx
4253  *
4254  * On success, returns 0 and fills out @ctx and @ctxlen with the security
4255  * context for the given @inode.
4256  *
4257  * Return: Returns 0 on success, error on failure.
4258  */
4259 int security_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen)
4260 {
4261 	struct security_hook_list *hp;
4262 	int rc;
4263 
4264 	/*
4265 	 * Only one module will provide a security context.
4266 	 */
4267 	hlist_for_each_entry(hp, &security_hook_heads.inode_getsecctx, list) {
4268 		rc = hp->hook.inode_getsecctx(inode, ctx, ctxlen);
4269 		if (rc != LSM_RET_DEFAULT(inode_getsecctx))
4270 			return rc;
4271 	}
4272 
4273 	return LSM_RET_DEFAULT(inode_getsecctx);
4274 }
4275 EXPORT_SYMBOL(security_inode_getsecctx);
4276 
4277 #ifdef CONFIG_WATCH_QUEUE
4278 /**
4279  * security_post_notification() - Check if a watch notification can be posted
4280  * @w_cred: credentials of the task that set the watch
4281  * @cred: credentials of the task which triggered the watch
4282  * @n: the notification
4283  *
4284  * Check to see if a watch notification can be posted to a particular queue.
4285  *
4286  * Return: Returns 0 if permission is granted.
4287  */
4288 int security_post_notification(const struct cred *w_cred,
4289 			       const struct cred *cred,
4290 			       struct watch_notification *n)
4291 {
4292 	return call_int_hook(post_notification, 0, w_cred, cred, n);
4293 }
4294 #endif /* CONFIG_WATCH_QUEUE */
4295 
4296 #ifdef CONFIG_KEY_NOTIFICATIONS
4297 /**
4298  * security_watch_key() - Check if a task is allowed to watch for key events
4299  * @key: the key to watch
4300  *
4301  * Check to see if a process is allowed to watch for event notifications from
4302  * a key or keyring.
4303  *
4304  * Return: Returns 0 if permission is granted.
4305  */
4306 int security_watch_key(struct key *key)
4307 {
4308 	return call_int_hook(watch_key, 0, key);
4309 }
4310 #endif /* CONFIG_KEY_NOTIFICATIONS */
4311 
4312 #ifdef CONFIG_SECURITY_NETWORK
4313 /**
4314  * security_unix_stream_connect() - Check if a AF_UNIX stream is allowed
4315  * @sock: originating sock
4316  * @other: peer sock
4317  * @newsk: new sock
4318  *
4319  * Check permissions before establishing a Unix domain stream connection
4320  * between @sock and @other.
4321  *
4322  * The @unix_stream_connect and @unix_may_send hooks were necessary because
4323  * Linux provides an alternative to the conventional file name space for Unix
4324  * domain sockets.  Whereas binding and connecting to sockets in the file name
4325  * space is mediated by the typical file permissions (and caught by the mknod
4326  * and permission hooks in inode_security_ops), binding and connecting to
4327  * sockets in the abstract name space is completely unmediated.  Sufficient
4328  * control of Unix domain sockets in the abstract name space isn't possible
4329  * using only the socket layer hooks, since we need to know the actual target
4330  * socket, which is not looked up until we are inside the af_unix code.
4331  *
4332  * Return: Returns 0 if permission is granted.
4333  */
4334 int security_unix_stream_connect(struct sock *sock, struct sock *other,
4335 				 struct sock *newsk)
4336 {
4337 	return call_int_hook(unix_stream_connect, 0, sock, other, newsk);
4338 }
4339 EXPORT_SYMBOL(security_unix_stream_connect);
4340 
4341 /**
4342  * security_unix_may_send() - Check if AF_UNIX socket can send datagrams
4343  * @sock: originating sock
4344  * @other: peer sock
4345  *
4346  * Check permissions before connecting or sending datagrams from @sock to
4347  * @other.
4348  *
4349  * The @unix_stream_connect and @unix_may_send hooks were necessary because
4350  * Linux provides an alternative to the conventional file name space for Unix
4351  * domain sockets.  Whereas binding and connecting to sockets in the file name
4352  * space is mediated by the typical file permissions (and caught by the mknod
4353  * and permission hooks in inode_security_ops), binding and connecting to
4354  * sockets in the abstract name space is completely unmediated.  Sufficient
4355  * control of Unix domain sockets in the abstract name space isn't possible
4356  * using only the socket layer hooks, since we need to know the actual target
4357  * socket, which is not looked up until we are inside the af_unix code.
4358  *
4359  * Return: Returns 0 if permission is granted.
4360  */
4361 int security_unix_may_send(struct socket *sock,  struct socket *other)
4362 {
4363 	return call_int_hook(unix_may_send, 0, sock, other);
4364 }
4365 EXPORT_SYMBOL(security_unix_may_send);
4366 
4367 /**
4368  * security_socket_create() - Check if creating a new socket is allowed
4369  * @family: protocol family
4370  * @type: communications type
4371  * @protocol: requested protocol
4372  * @kern: set to 1 if a kernel socket is requested
4373  *
4374  * Check permissions prior to creating a new socket.
4375  *
4376  * Return: Returns 0 if permission is granted.
4377  */
4378 int security_socket_create(int family, int type, int protocol, int kern)
4379 {
4380 	return call_int_hook(socket_create, 0, family, type, protocol, kern);
4381 }
4382 
4383 /**
4384  * security_socket_post_create() - Initialize a newly created socket
4385  * @sock: socket
4386  * @family: protocol family
4387  * @type: communications type
4388  * @protocol: requested protocol
4389  * @kern: set to 1 if a kernel socket is requested
4390  *
4391  * This hook allows a module to update or allocate a per-socket security
4392  * structure. Note that the security field was not added directly to the socket
4393  * structure, but rather, the socket security information is stored in the
4394  * associated inode.  Typically, the inode alloc_security hook will allocate
4395  * and attach security information to SOCK_INODE(sock)->i_security.  This hook
4396  * may be used to update the SOCK_INODE(sock)->i_security field with additional
4397  * information that wasn't available when the inode was allocated.
4398  *
4399  * Return: Returns 0 if permission is granted.
4400  */
4401 int security_socket_post_create(struct socket *sock, int family,
4402 				int type, int protocol, int kern)
4403 {
4404 	return call_int_hook(socket_post_create, 0, sock, family, type,
4405 			     protocol, kern);
4406 }
4407 
4408 /**
4409  * security_socket_socketpair() - Check if creating a socketpair is allowed
4410  * @socka: first socket
4411  * @sockb: second socket
4412  *
4413  * Check permissions before creating a fresh pair of sockets.
4414  *
4415  * Return: Returns 0 if permission is granted and the connection was
4416  *         established.
4417  */
4418 int security_socket_socketpair(struct socket *socka, struct socket *sockb)
4419 {
4420 	return call_int_hook(socket_socketpair, 0, socka, sockb);
4421 }
4422 EXPORT_SYMBOL(security_socket_socketpair);
4423 
4424 /**
4425  * security_socket_bind() - Check if a socket bind operation is allowed
4426  * @sock: socket
4427  * @address: requested bind address
4428  * @addrlen: length of address
4429  *
4430  * Check permission before socket protocol layer bind operation is performed
4431  * and the socket @sock is bound to the address specified in the @address
4432  * parameter.
4433  *
4434  * Return: Returns 0 if permission is granted.
4435  */
4436 int security_socket_bind(struct socket *sock,
4437 			 struct sockaddr *address, int addrlen)
4438 {
4439 	return call_int_hook(socket_bind, 0, sock, address, addrlen);
4440 }
4441 
4442 /**
4443  * security_socket_connect() - Check if a socket connect operation is allowed
4444  * @sock: socket
4445  * @address: address of remote connection point
4446  * @addrlen: length of address
4447  *
4448  * Check permission before socket protocol layer connect operation attempts to
4449  * connect socket @sock to a remote address, @address.
4450  *
4451  * Return: Returns 0 if permission is granted.
4452  */
4453 int security_socket_connect(struct socket *sock,
4454 			    struct sockaddr *address, int addrlen)
4455 {
4456 	return call_int_hook(socket_connect, 0, sock, address, addrlen);
4457 }
4458 
4459 /**
4460  * security_socket_listen() - Check if a socket is allowed to listen
4461  * @sock: socket
4462  * @backlog: connection queue size
4463  *
4464  * Check permission before socket protocol layer listen operation.
4465  *
4466  * Return: Returns 0 if permission is granted.
4467  */
4468 int security_socket_listen(struct socket *sock, int backlog)
4469 {
4470 	return call_int_hook(socket_listen, 0, sock, backlog);
4471 }
4472 
4473 /**
4474  * security_socket_accept() - Check if a socket is allowed to accept connections
4475  * @sock: listening socket
4476  * @newsock: newly creation connection socket
4477  *
4478  * Check permission before accepting a new connection.  Note that the new
4479  * socket, @newsock, has been created and some information copied to it, but
4480  * the accept operation has not actually been performed.
4481  *
4482  * Return: Returns 0 if permission is granted.
4483  */
4484 int security_socket_accept(struct socket *sock, struct socket *newsock)
4485 {
4486 	return call_int_hook(socket_accept, 0, sock, newsock);
4487 }
4488 
4489 /**
4490  * security_socket_sendmsg() - Check is sending a message is allowed
4491  * @sock: sending socket
4492  * @msg: message to send
4493  * @size: size of message
4494  *
4495  * Check permission before transmitting a message to another socket.
4496  *
4497  * Return: Returns 0 if permission is granted.
4498  */
4499 int security_socket_sendmsg(struct socket *sock, struct msghdr *msg, int size)
4500 {
4501 	return call_int_hook(socket_sendmsg, 0, sock, msg, size);
4502 }
4503 
4504 /**
4505  * security_socket_recvmsg() - Check if receiving a message is allowed
4506  * @sock: receiving socket
4507  * @msg: message to receive
4508  * @size: size of message
4509  * @flags: operational flags
4510  *
4511  * Check permission before receiving a message from a socket.
4512  *
4513  * Return: Returns 0 if permission is granted.
4514  */
4515 int security_socket_recvmsg(struct socket *sock, struct msghdr *msg,
4516 			    int size, int flags)
4517 {
4518 	return call_int_hook(socket_recvmsg, 0, sock, msg, size, flags);
4519 }
4520 
4521 /**
4522  * security_socket_getsockname() - Check if reading the socket addr is allowed
4523  * @sock: socket
4524  *
4525  * Check permission before reading the local address (name) of the socket
4526  * object.
4527  *
4528  * Return: Returns 0 if permission is granted.
4529  */
4530 int security_socket_getsockname(struct socket *sock)
4531 {
4532 	return call_int_hook(socket_getsockname, 0, sock);
4533 }
4534 
4535 /**
4536  * security_socket_getpeername() - Check if reading the peer's addr is allowed
4537  * @sock: socket
4538  *
4539  * Check permission before the remote address (name) of a socket object.
4540  *
4541  * Return: Returns 0 if permission is granted.
4542  */
4543 int security_socket_getpeername(struct socket *sock)
4544 {
4545 	return call_int_hook(socket_getpeername, 0, sock);
4546 }
4547 
4548 /**
4549  * security_socket_getsockopt() - Check if reading a socket option is allowed
4550  * @sock: socket
4551  * @level: option's protocol level
4552  * @optname: option name
4553  *
4554  * Check permissions before retrieving the options associated with socket
4555  * @sock.
4556  *
4557  * Return: Returns 0 if permission is granted.
4558  */
4559 int security_socket_getsockopt(struct socket *sock, int level, int optname)
4560 {
4561 	return call_int_hook(socket_getsockopt, 0, sock, level, optname);
4562 }
4563 
4564 /**
4565  * security_socket_setsockopt() - Check if setting a socket option is allowed
4566  * @sock: socket
4567  * @level: option's protocol level
4568  * @optname: option name
4569  *
4570  * Check permissions before setting the options associated with socket @sock.
4571  *
4572  * Return: Returns 0 if permission is granted.
4573  */
4574 int security_socket_setsockopt(struct socket *sock, int level, int optname)
4575 {
4576 	return call_int_hook(socket_setsockopt, 0, sock, level, optname);
4577 }
4578 
4579 /**
4580  * security_socket_shutdown() - Checks if shutting down the socket is allowed
4581  * @sock: socket
4582  * @how: flag indicating how sends and receives are handled
4583  *
4584  * Checks permission before all or part of a connection on the socket @sock is
4585  * shut down.
4586  *
4587  * Return: Returns 0 if permission is granted.
4588  */
4589 int security_socket_shutdown(struct socket *sock, int how)
4590 {
4591 	return call_int_hook(socket_shutdown, 0, sock, how);
4592 }
4593 
4594 /**
4595  * security_sock_rcv_skb() - Check if an incoming network packet is allowed
4596  * @sk: destination sock
4597  * @skb: incoming packet
4598  *
4599  * Check permissions on incoming network packets.  This hook is distinct from
4600  * Netfilter's IP input hooks since it is the first time that the incoming
4601  * sk_buff @skb has been associated with a particular socket, @sk.  Must not
4602  * sleep inside this hook because some callers hold spinlocks.
4603  *
4604  * Return: Returns 0 if permission is granted.
4605  */
4606 int security_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
4607 {
4608 	return call_int_hook(socket_sock_rcv_skb, 0, sk, skb);
4609 }
4610 EXPORT_SYMBOL(security_sock_rcv_skb);
4611 
4612 /**
4613  * security_socket_getpeersec_stream() - Get the remote peer label
4614  * @sock: socket
4615  * @optval: destination buffer
4616  * @optlen: size of peer label copied into the buffer
4617  * @len: maximum size of the destination buffer
4618  *
4619  * This hook allows the security module to provide peer socket security state
4620  * for unix or connected tcp sockets to userspace via getsockopt SO_GETPEERSEC.
4621  * For tcp sockets this can be meaningful if the socket is associated with an
4622  * ipsec SA.
4623  *
4624  * Return: Returns 0 if all is well, otherwise, typical getsockopt return
4625  *         values.
4626  */
4627 int security_socket_getpeersec_stream(struct socket *sock, sockptr_t optval,
4628 				      sockptr_t optlen, unsigned int len)
4629 {
4630 	struct security_hook_list *hp;
4631 	int rc;
4632 
4633 	/*
4634 	 * Only one module will provide a security context.
4635 	 */
4636 	hlist_for_each_entry(hp, &security_hook_heads.socket_getpeersec_stream,
4637 			     list) {
4638 		rc = hp->hook.socket_getpeersec_stream(sock, optval, optlen,
4639 						       len);
4640 		if (rc != LSM_RET_DEFAULT(socket_getpeersec_stream))
4641 			return rc;
4642 	}
4643 	return LSM_RET_DEFAULT(socket_getpeersec_stream);
4644 }
4645 
4646 /**
4647  * security_socket_getpeersec_dgram() - Get the remote peer label
4648  * @sock: socket
4649  * @skb: datagram packet
4650  * @secid: remote peer label secid
4651  *
4652  * This hook allows the security module to provide peer socket security state
4653  * for udp sockets on a per-packet basis to userspace via getsockopt
4654  * SO_GETPEERSEC. The application must first have indicated the IP_PASSSEC
4655  * option via getsockopt. It can then retrieve the security state returned by
4656  * this hook for a packet via the SCM_SECURITY ancillary message type.
4657  *
4658  * Return: Returns 0 on success, error on failure.
4659  */
4660 int security_socket_getpeersec_dgram(struct socket *sock,
4661 				     struct sk_buff *skb, u32 *secid)
4662 {
4663 	struct security_hook_list *hp;
4664 	int rc;
4665 
4666 	/*
4667 	 * Only one module will provide a security context.
4668 	 */
4669 	hlist_for_each_entry(hp, &security_hook_heads.socket_getpeersec_dgram,
4670 			     list) {
4671 		rc = hp->hook.socket_getpeersec_dgram(sock, skb, secid);
4672 		if (rc != LSM_RET_DEFAULT(socket_getpeersec_dgram))
4673 			return rc;
4674 	}
4675 	return LSM_RET_DEFAULT(socket_getpeersec_dgram);
4676 }
4677 EXPORT_SYMBOL(security_socket_getpeersec_dgram);
4678 
4679 /**
4680  * security_sk_alloc() - Allocate and initialize a sock's LSM blob
4681  * @sk: sock
4682  * @family: protocol family
4683  * @priority: gfp flags
4684  *
4685  * Allocate and attach a security structure to the sk->sk_security field, which
4686  * is used to copy security attributes between local stream sockets.
4687  *
4688  * Return: Returns 0 on success, error on failure.
4689  */
4690 int security_sk_alloc(struct sock *sk, int family, gfp_t priority)
4691 {
4692 	return call_int_hook(sk_alloc_security, 0, sk, family, priority);
4693 }
4694 
4695 /**
4696  * security_sk_free() - Free the sock's LSM blob
4697  * @sk: sock
4698  *
4699  * Deallocate security structure.
4700  */
4701 void security_sk_free(struct sock *sk)
4702 {
4703 	call_void_hook(sk_free_security, sk);
4704 }
4705 
4706 /**
4707  * security_sk_clone() - Clone a sock's LSM state
4708  * @sk: original sock
4709  * @newsk: target sock
4710  *
4711  * Clone/copy security structure.
4712  */
4713 void security_sk_clone(const struct sock *sk, struct sock *newsk)
4714 {
4715 	call_void_hook(sk_clone_security, sk, newsk);
4716 }
4717 EXPORT_SYMBOL(security_sk_clone);
4718 
4719 /**
4720  * security_sk_classify_flow() - Set a flow's secid based on socket
4721  * @sk: original socket
4722  * @flic: target flow
4723  *
4724  * Set the target flow's secid to socket's secid.
4725  */
4726 void security_sk_classify_flow(const struct sock *sk, struct flowi_common *flic)
4727 {
4728 	call_void_hook(sk_getsecid, sk, &flic->flowic_secid);
4729 }
4730 EXPORT_SYMBOL(security_sk_classify_flow);
4731 
4732 /**
4733  * security_req_classify_flow() - Set a flow's secid based on request_sock
4734  * @req: request_sock
4735  * @flic: target flow
4736  *
4737  * Sets @flic's secid to @req's secid.
4738  */
4739 void security_req_classify_flow(const struct request_sock *req,
4740 				struct flowi_common *flic)
4741 {
4742 	call_void_hook(req_classify_flow, req, flic);
4743 }
4744 EXPORT_SYMBOL(security_req_classify_flow);
4745 
4746 /**
4747  * security_sock_graft() - Reconcile LSM state when grafting a sock on a socket
4748  * @sk: sock being grafted
4749  * @parent: target parent socket
4750  *
4751  * Sets @parent's inode secid to @sk's secid and update @sk with any necessary
4752  * LSM state from @parent.
4753  */
4754 void security_sock_graft(struct sock *sk, struct socket *parent)
4755 {
4756 	call_void_hook(sock_graft, sk, parent);
4757 }
4758 EXPORT_SYMBOL(security_sock_graft);
4759 
4760 /**
4761  * security_inet_conn_request() - Set request_sock state using incoming connect
4762  * @sk: parent listening sock
4763  * @skb: incoming connection
4764  * @req: new request_sock
4765  *
4766  * Initialize the @req LSM state based on @sk and the incoming connect in @skb.
4767  *
4768  * Return: Returns 0 if permission is granted.
4769  */
4770 int security_inet_conn_request(const struct sock *sk,
4771 			       struct sk_buff *skb, struct request_sock *req)
4772 {
4773 	return call_int_hook(inet_conn_request, 0, sk, skb, req);
4774 }
4775 EXPORT_SYMBOL(security_inet_conn_request);
4776 
4777 /**
4778  * security_inet_csk_clone() - Set new sock LSM state based on request_sock
4779  * @newsk: new sock
4780  * @req: connection request_sock
4781  *
4782  * Set that LSM state of @sock using the LSM state from @req.
4783  */
4784 void security_inet_csk_clone(struct sock *newsk,
4785 			     const struct request_sock *req)
4786 {
4787 	call_void_hook(inet_csk_clone, newsk, req);
4788 }
4789 
4790 /**
4791  * security_inet_conn_established() - Update sock's LSM state with connection
4792  * @sk: sock
4793  * @skb: connection packet
4794  *
4795  * Update @sock's LSM state to represent a new connection from @skb.
4796  */
4797 void security_inet_conn_established(struct sock *sk,
4798 				    struct sk_buff *skb)
4799 {
4800 	call_void_hook(inet_conn_established, sk, skb);
4801 }
4802 EXPORT_SYMBOL(security_inet_conn_established);
4803 
4804 /**
4805  * security_secmark_relabel_packet() - Check if setting a secmark is allowed
4806  * @secid: new secmark value
4807  *
4808  * Check if the process should be allowed to relabel packets to @secid.
4809  *
4810  * Return: Returns 0 if permission is granted.
4811  */
4812 int security_secmark_relabel_packet(u32 secid)
4813 {
4814 	return call_int_hook(secmark_relabel_packet, 0, secid);
4815 }
4816 EXPORT_SYMBOL(security_secmark_relabel_packet);
4817 
4818 /**
4819  * security_secmark_refcount_inc() - Increment the secmark labeling rule count
4820  *
4821  * Tells the LSM to increment the number of secmark labeling rules loaded.
4822  */
4823 void security_secmark_refcount_inc(void)
4824 {
4825 	call_void_hook(secmark_refcount_inc);
4826 }
4827 EXPORT_SYMBOL(security_secmark_refcount_inc);
4828 
4829 /**
4830  * security_secmark_refcount_dec() - Decrement the secmark labeling rule count
4831  *
4832  * Tells the LSM to decrement the number of secmark labeling rules loaded.
4833  */
4834 void security_secmark_refcount_dec(void)
4835 {
4836 	call_void_hook(secmark_refcount_dec);
4837 }
4838 EXPORT_SYMBOL(security_secmark_refcount_dec);
4839 
4840 /**
4841  * security_tun_dev_alloc_security() - Allocate a LSM blob for a TUN device
4842  * @security: pointer to the LSM blob
4843  *
4844  * This hook allows a module to allocate a security structure for a TUN	device,
4845  * returning the pointer in @security.
4846  *
4847  * Return: Returns a zero on success, negative values on failure.
4848  */
4849 int security_tun_dev_alloc_security(void **security)
4850 {
4851 	return call_int_hook(tun_dev_alloc_security, 0, security);
4852 }
4853 EXPORT_SYMBOL(security_tun_dev_alloc_security);
4854 
4855 /**
4856  * security_tun_dev_free_security() - Free a TUN device LSM blob
4857  * @security: LSM blob
4858  *
4859  * This hook allows a module to free the security structure for a TUN device.
4860  */
4861 void security_tun_dev_free_security(void *security)
4862 {
4863 	call_void_hook(tun_dev_free_security, security);
4864 }
4865 EXPORT_SYMBOL(security_tun_dev_free_security);
4866 
4867 /**
4868  * security_tun_dev_create() - Check if creating a TUN device is allowed
4869  *
4870  * Check permissions prior to creating a new TUN device.
4871  *
4872  * Return: Returns 0 if permission is granted.
4873  */
4874 int security_tun_dev_create(void)
4875 {
4876 	return call_int_hook(tun_dev_create, 0);
4877 }
4878 EXPORT_SYMBOL(security_tun_dev_create);
4879 
4880 /**
4881  * security_tun_dev_attach_queue() - Check if attaching a TUN queue is allowed
4882  * @security: TUN device LSM blob
4883  *
4884  * Check permissions prior to attaching to a TUN device queue.
4885  *
4886  * Return: Returns 0 if permission is granted.
4887  */
4888 int security_tun_dev_attach_queue(void *security)
4889 {
4890 	return call_int_hook(tun_dev_attach_queue, 0, security);
4891 }
4892 EXPORT_SYMBOL(security_tun_dev_attach_queue);
4893 
4894 /**
4895  * security_tun_dev_attach() - Update TUN device LSM state on attach
4896  * @sk: associated sock
4897  * @security: TUN device LSM blob
4898  *
4899  * This hook can be used by the module to update any security state associated
4900  * with the TUN device's sock structure.
4901  *
4902  * Return: Returns 0 if permission is granted.
4903  */
4904 int security_tun_dev_attach(struct sock *sk, void *security)
4905 {
4906 	return call_int_hook(tun_dev_attach, 0, sk, security);
4907 }
4908 EXPORT_SYMBOL(security_tun_dev_attach);
4909 
4910 /**
4911  * security_tun_dev_open() - Update TUN device LSM state on open
4912  * @security: TUN device LSM blob
4913  *
4914  * This hook can be used by the module to update any security state associated
4915  * with the TUN device's security structure.
4916  *
4917  * Return: Returns 0 if permission is granted.
4918  */
4919 int security_tun_dev_open(void *security)
4920 {
4921 	return call_int_hook(tun_dev_open, 0, security);
4922 }
4923 EXPORT_SYMBOL(security_tun_dev_open);
4924 
4925 /**
4926  * security_sctp_assoc_request() - Update the LSM on a SCTP association req
4927  * @asoc: SCTP association
4928  * @skb: packet requesting the association
4929  *
4930  * Passes the @asoc and @chunk->skb of the association INIT packet to the LSM.
4931  *
4932  * Return: Returns 0 on success, error on failure.
4933  */
4934 int security_sctp_assoc_request(struct sctp_association *asoc,
4935 				struct sk_buff *skb)
4936 {
4937 	return call_int_hook(sctp_assoc_request, 0, asoc, skb);
4938 }
4939 EXPORT_SYMBOL(security_sctp_assoc_request);
4940 
4941 /**
4942  * security_sctp_bind_connect() - Validate a list of addrs for a SCTP option
4943  * @sk: socket
4944  * @optname: SCTP option to validate
4945  * @address: list of IP addresses to validate
4946  * @addrlen: length of the address list
4947  *
4948  * Validiate permissions required for each address associated with sock	@sk.
4949  * Depending on @optname, the addresses will be treated as either a connect or
4950  * bind service. The @addrlen is calculated on each IPv4 and IPv6 address using
4951  * sizeof(struct sockaddr_in) or sizeof(struct sockaddr_in6).
4952  *
4953  * Return: Returns 0 on success, error on failure.
4954  */
4955 int security_sctp_bind_connect(struct sock *sk, int optname,
4956 			       struct sockaddr *address, int addrlen)
4957 {
4958 	return call_int_hook(sctp_bind_connect, 0, sk, optname,
4959 			     address, addrlen);
4960 }
4961 EXPORT_SYMBOL(security_sctp_bind_connect);
4962 
4963 /**
4964  * security_sctp_sk_clone() - Clone a SCTP sock's LSM state
4965  * @asoc: SCTP association
4966  * @sk: original sock
4967  * @newsk: target sock
4968  *
4969  * Called whenever a new socket is created by accept(2) (i.e. a TCP style
4970  * socket) or when a socket is 'peeled off' e.g userspace calls
4971  * sctp_peeloff(3).
4972  */
4973 void security_sctp_sk_clone(struct sctp_association *asoc, struct sock *sk,
4974 			    struct sock *newsk)
4975 {
4976 	call_void_hook(sctp_sk_clone, asoc, sk, newsk);
4977 }
4978 EXPORT_SYMBOL(security_sctp_sk_clone);
4979 
4980 /**
4981  * security_sctp_assoc_established() - Update LSM state when assoc established
4982  * @asoc: SCTP association
4983  * @skb: packet establishing the association
4984  *
4985  * Passes the @asoc and @chunk->skb of the association COOKIE_ACK packet to the
4986  * security module.
4987  *
4988  * Return: Returns 0 if permission is granted.
4989  */
4990 int security_sctp_assoc_established(struct sctp_association *asoc,
4991 				    struct sk_buff *skb)
4992 {
4993 	return call_int_hook(sctp_assoc_established, 0, asoc, skb);
4994 }
4995 EXPORT_SYMBOL(security_sctp_assoc_established);
4996 
4997 /**
4998  * security_mptcp_add_subflow() - Inherit the LSM label from the MPTCP socket
4999  * @sk: the owning MPTCP socket
5000  * @ssk: the new subflow
5001  *
5002  * Update the labeling for the given MPTCP subflow, to match the one of the
5003  * owning MPTCP socket. This hook has to be called after the socket creation and
5004  * initialization via the security_socket_create() and
5005  * security_socket_post_create() LSM hooks.
5006  *
5007  * Return: Returns 0 on success or a negative error code on failure.
5008  */
5009 int security_mptcp_add_subflow(struct sock *sk, struct sock *ssk)
5010 {
5011 	return call_int_hook(mptcp_add_subflow, 0, sk, ssk);
5012 }
5013 
5014 #endif	/* CONFIG_SECURITY_NETWORK */
5015 
5016 #ifdef CONFIG_SECURITY_INFINIBAND
5017 /**
5018  * security_ib_pkey_access() - Check if access to an IB pkey is allowed
5019  * @sec: LSM blob
5020  * @subnet_prefix: subnet prefix of the port
5021  * @pkey: IB pkey
5022  *
5023  * Check permission to access a pkey when modifying a QP.
5024  *
5025  * Return: Returns 0 if permission is granted.
5026  */
5027 int security_ib_pkey_access(void *sec, u64 subnet_prefix, u16 pkey)
5028 {
5029 	return call_int_hook(ib_pkey_access, 0, sec, subnet_prefix, pkey);
5030 }
5031 EXPORT_SYMBOL(security_ib_pkey_access);
5032 
5033 /**
5034  * security_ib_endport_manage_subnet() - Check if SMPs traffic is allowed
5035  * @sec: LSM blob
5036  * @dev_name: IB device name
5037  * @port_num: port number
5038  *
5039  * Check permissions to send and receive SMPs on a end port.
5040  *
5041  * Return: Returns 0 if permission is granted.
5042  */
5043 int security_ib_endport_manage_subnet(void *sec,
5044 				      const char *dev_name, u8 port_num)
5045 {
5046 	return call_int_hook(ib_endport_manage_subnet, 0, sec,
5047 			     dev_name, port_num);
5048 }
5049 EXPORT_SYMBOL(security_ib_endport_manage_subnet);
5050 
5051 /**
5052  * security_ib_alloc_security() - Allocate an Infiniband LSM blob
5053  * @sec: LSM blob
5054  *
5055  * Allocate a security structure for Infiniband objects.
5056  *
5057  * Return: Returns 0 on success, non-zero on failure.
5058  */
5059 int security_ib_alloc_security(void **sec)
5060 {
5061 	return call_int_hook(ib_alloc_security, 0, sec);
5062 }
5063 EXPORT_SYMBOL(security_ib_alloc_security);
5064 
5065 /**
5066  * security_ib_free_security() - Free an Infiniband LSM blob
5067  * @sec: LSM blob
5068  *
5069  * Deallocate an Infiniband security structure.
5070  */
5071 void security_ib_free_security(void *sec)
5072 {
5073 	call_void_hook(ib_free_security, sec);
5074 }
5075 EXPORT_SYMBOL(security_ib_free_security);
5076 #endif	/* CONFIG_SECURITY_INFINIBAND */
5077 
5078 #ifdef CONFIG_SECURITY_NETWORK_XFRM
5079 /**
5080  * security_xfrm_policy_alloc() - Allocate a xfrm policy LSM blob
5081  * @ctxp: xfrm security context being added to the SPD
5082  * @sec_ctx: security label provided by userspace
5083  * @gfp: gfp flags
5084  *
5085  * Allocate a security structure to the xp->security field; the security field
5086  * is initialized to NULL when the xfrm_policy is allocated.
5087  *
5088  * Return:  Return 0 if operation was successful.
5089  */
5090 int security_xfrm_policy_alloc(struct xfrm_sec_ctx **ctxp,
5091 			       struct xfrm_user_sec_ctx *sec_ctx,
5092 			       gfp_t gfp)
5093 {
5094 	return call_int_hook(xfrm_policy_alloc_security, 0, ctxp, sec_ctx, gfp);
5095 }
5096 EXPORT_SYMBOL(security_xfrm_policy_alloc);
5097 
5098 /**
5099  * security_xfrm_policy_clone() - Clone xfrm policy LSM state
5100  * @old_ctx: xfrm security context
5101  * @new_ctxp: target xfrm security context
5102  *
5103  * Allocate a security structure in new_ctxp that contains the information from
5104  * the old_ctx structure.
5105  *
5106  * Return: Return 0 if operation was successful.
5107  */
5108 int security_xfrm_policy_clone(struct xfrm_sec_ctx *old_ctx,
5109 			       struct xfrm_sec_ctx **new_ctxp)
5110 {
5111 	return call_int_hook(xfrm_policy_clone_security, 0, old_ctx, new_ctxp);
5112 }
5113 
5114 /**
5115  * security_xfrm_policy_free() - Free a xfrm security context
5116  * @ctx: xfrm security context
5117  *
5118  * Free LSM resources associated with @ctx.
5119  */
5120 void security_xfrm_policy_free(struct xfrm_sec_ctx *ctx)
5121 {
5122 	call_void_hook(xfrm_policy_free_security, ctx);
5123 }
5124 EXPORT_SYMBOL(security_xfrm_policy_free);
5125 
5126 /**
5127  * security_xfrm_policy_delete() - Check if deleting a xfrm policy is allowed
5128  * @ctx: xfrm security context
5129  *
5130  * Authorize deletion of a SPD entry.
5131  *
5132  * Return: Returns 0 if permission is granted.
5133  */
5134 int security_xfrm_policy_delete(struct xfrm_sec_ctx *ctx)
5135 {
5136 	return call_int_hook(xfrm_policy_delete_security, 0, ctx);
5137 }
5138 
5139 /**
5140  * security_xfrm_state_alloc() - Allocate a xfrm state LSM blob
5141  * @x: xfrm state being added to the SAD
5142  * @sec_ctx: security label provided by userspace
5143  *
5144  * Allocate a security structure to the @x->security field; the security field
5145  * is initialized to NULL when the xfrm_state is allocated. Set the context to
5146  * correspond to @sec_ctx.
5147  *
5148  * Return: Return 0 if operation was successful.
5149  */
5150 int security_xfrm_state_alloc(struct xfrm_state *x,
5151 			      struct xfrm_user_sec_ctx *sec_ctx)
5152 {
5153 	return call_int_hook(xfrm_state_alloc, 0, x, sec_ctx);
5154 }
5155 EXPORT_SYMBOL(security_xfrm_state_alloc);
5156 
5157 /**
5158  * security_xfrm_state_alloc_acquire() - Allocate a xfrm state LSM blob
5159  * @x: xfrm state being added to the SAD
5160  * @polsec: associated policy's security context
5161  * @secid: secid from the flow
5162  *
5163  * Allocate a security structure to the x->security field; the security field
5164  * is initialized to NULL when the xfrm_state is allocated.  Set the context to
5165  * correspond to secid.
5166  *
5167  * Return: Returns 0 if operation was successful.
5168  */
5169 int security_xfrm_state_alloc_acquire(struct xfrm_state *x,
5170 				      struct xfrm_sec_ctx *polsec, u32 secid)
5171 {
5172 	return call_int_hook(xfrm_state_alloc_acquire, 0, x, polsec, secid);
5173 }
5174 
5175 /**
5176  * security_xfrm_state_delete() - Check if deleting a xfrm state is allowed
5177  * @x: xfrm state
5178  *
5179  * Authorize deletion of x->security.
5180  *
5181  * Return: Returns 0 if permission is granted.
5182  */
5183 int security_xfrm_state_delete(struct xfrm_state *x)
5184 {
5185 	return call_int_hook(xfrm_state_delete_security, 0, x);
5186 }
5187 EXPORT_SYMBOL(security_xfrm_state_delete);
5188 
5189 /**
5190  * security_xfrm_state_free() - Free a xfrm state
5191  * @x: xfrm state
5192  *
5193  * Deallocate x->security.
5194  */
5195 void security_xfrm_state_free(struct xfrm_state *x)
5196 {
5197 	call_void_hook(xfrm_state_free_security, x);
5198 }
5199 
5200 /**
5201  * security_xfrm_policy_lookup() - Check if using a xfrm policy is allowed
5202  * @ctx: target xfrm security context
5203  * @fl_secid: flow secid used to authorize access
5204  *
5205  * Check permission when a flow selects a xfrm_policy for processing XFRMs on a
5206  * packet.  The hook is called when selecting either a per-socket policy or a
5207  * generic xfrm policy.
5208  *
5209  * Return: Return 0 if permission is granted, -ESRCH otherwise, or -errno on
5210  *         other errors.
5211  */
5212 int security_xfrm_policy_lookup(struct xfrm_sec_ctx *ctx, u32 fl_secid)
5213 {
5214 	return call_int_hook(xfrm_policy_lookup, 0, ctx, fl_secid);
5215 }
5216 
5217 /**
5218  * security_xfrm_state_pol_flow_match() - Check for a xfrm match
5219  * @x: xfrm state to match
5220  * @xp: xfrm policy to check for a match
5221  * @flic: flow to check for a match.
5222  *
5223  * Check @xp and @flic for a match with @x.
5224  *
5225  * Return: Returns 1 if there is a match.
5226  */
5227 int security_xfrm_state_pol_flow_match(struct xfrm_state *x,
5228 				       struct xfrm_policy *xp,
5229 				       const struct flowi_common *flic)
5230 {
5231 	struct security_hook_list *hp;
5232 	int rc = LSM_RET_DEFAULT(xfrm_state_pol_flow_match);
5233 
5234 	/*
5235 	 * Since this function is expected to return 0 or 1, the judgment
5236 	 * becomes difficult if multiple LSMs supply this call. Fortunately,
5237 	 * we can use the first LSM's judgment because currently only SELinux
5238 	 * supplies this call.
5239 	 *
5240 	 * For speed optimization, we explicitly break the loop rather than
5241 	 * using the macro
5242 	 */
5243 	hlist_for_each_entry(hp, &security_hook_heads.xfrm_state_pol_flow_match,
5244 			     list) {
5245 		rc = hp->hook.xfrm_state_pol_flow_match(x, xp, flic);
5246 		break;
5247 	}
5248 	return rc;
5249 }
5250 
5251 /**
5252  * security_xfrm_decode_session() - Determine the xfrm secid for a packet
5253  * @skb: xfrm packet
5254  * @secid: secid
5255  *
5256  * Decode the packet in @skb and return the security label in @secid.
5257  *
5258  * Return: Return 0 if all xfrms used have the same secid.
5259  */
5260 int security_xfrm_decode_session(struct sk_buff *skb, u32 *secid)
5261 {
5262 	return call_int_hook(xfrm_decode_session, 0, skb, secid, 1);
5263 }
5264 
5265 void security_skb_classify_flow(struct sk_buff *skb, struct flowi_common *flic)
5266 {
5267 	int rc = call_int_hook(xfrm_decode_session, 0, skb, &flic->flowic_secid,
5268 			       0);
5269 
5270 	BUG_ON(rc);
5271 }
5272 EXPORT_SYMBOL(security_skb_classify_flow);
5273 #endif	/* CONFIG_SECURITY_NETWORK_XFRM */
5274 
5275 #ifdef CONFIG_KEYS
5276 /**
5277  * security_key_alloc() - Allocate and initialize a kernel key LSM blob
5278  * @key: key
5279  * @cred: credentials
5280  * @flags: allocation flags
5281  *
5282  * Permit allocation of a key and assign security data. Note that key does not
5283  * have a serial number assigned at this point.
5284  *
5285  * Return: Return 0 if permission is granted, -ve error otherwise.
5286  */
5287 int security_key_alloc(struct key *key, const struct cred *cred,
5288 		       unsigned long flags)
5289 {
5290 	return call_int_hook(key_alloc, 0, key, cred, flags);
5291 }
5292 
5293 /**
5294  * security_key_free() - Free a kernel key LSM blob
5295  * @key: key
5296  *
5297  * Notification of destruction; free security data.
5298  */
5299 void security_key_free(struct key *key)
5300 {
5301 	call_void_hook(key_free, key);
5302 }
5303 
5304 /**
5305  * security_key_permission() - Check if a kernel key operation is allowed
5306  * @key_ref: key reference
5307  * @cred: credentials of actor requesting access
5308  * @need_perm: requested permissions
5309  *
5310  * See whether a specific operational right is granted to a process on a key.
5311  *
5312  * Return: Return 0 if permission is granted, -ve error otherwise.
5313  */
5314 int security_key_permission(key_ref_t key_ref, const struct cred *cred,
5315 			    enum key_need_perm need_perm)
5316 {
5317 	return call_int_hook(key_permission, 0, key_ref, cred, need_perm);
5318 }
5319 
5320 /**
5321  * security_key_getsecurity() - Get the key's security label
5322  * @key: key
5323  * @buffer: security label buffer
5324  *
5325  * Get a textual representation of the security context attached to a key for
5326  * the purposes of honouring KEYCTL_GETSECURITY.  This function allocates the
5327  * storage for the NUL-terminated string and the caller should free it.
5328  *
5329  * Return: Returns the length of @buffer (including terminating NUL) or -ve if
5330  *         an error occurs.  May also return 0 (and a NULL buffer pointer) if
5331  *         there is no security label assigned to the key.
5332  */
5333 int security_key_getsecurity(struct key *key, char **buffer)
5334 {
5335 	*buffer = NULL;
5336 	return call_int_hook(key_getsecurity, 0, key, buffer);
5337 }
5338 #endif	/* CONFIG_KEYS */
5339 
5340 #ifdef CONFIG_AUDIT
5341 /**
5342  * security_audit_rule_init() - Allocate and init an LSM audit rule struct
5343  * @field: audit action
5344  * @op: rule operator
5345  * @rulestr: rule context
5346  * @lsmrule: receive buffer for audit rule struct
5347  *
5348  * Allocate and initialize an LSM audit rule structure.
5349  *
5350  * Return: Return 0 if @lsmrule has been successfully set, -EINVAL in case of
5351  *         an invalid rule.
5352  */
5353 int security_audit_rule_init(u32 field, u32 op, char *rulestr, void **lsmrule)
5354 {
5355 	return call_int_hook(audit_rule_init, 0, field, op, rulestr, lsmrule);
5356 }
5357 
5358 /**
5359  * security_audit_rule_known() - Check if an audit rule contains LSM fields
5360  * @krule: audit rule
5361  *
5362  * Specifies whether given @krule contains any fields related to the current
5363  * LSM.
5364  *
5365  * Return: Returns 1 in case of relation found, 0 otherwise.
5366  */
5367 int security_audit_rule_known(struct audit_krule *krule)
5368 {
5369 	return call_int_hook(audit_rule_known, 0, krule);
5370 }
5371 
5372 /**
5373  * security_audit_rule_free() - Free an LSM audit rule struct
5374  * @lsmrule: audit rule struct
5375  *
5376  * Deallocate the LSM audit rule structure previously allocated by
5377  * audit_rule_init().
5378  */
5379 void security_audit_rule_free(void *lsmrule)
5380 {
5381 	call_void_hook(audit_rule_free, lsmrule);
5382 }
5383 
5384 /**
5385  * security_audit_rule_match() - Check if a label matches an audit rule
5386  * @secid: security label
5387  * @field: LSM audit field
5388  * @op: matching operator
5389  * @lsmrule: audit rule
5390  *
5391  * Determine if given @secid matches a rule previously approved by
5392  * security_audit_rule_known().
5393  *
5394  * Return: Returns 1 if secid matches the rule, 0 if it does not, -ERRNO on
5395  *         failure.
5396  */
5397 int security_audit_rule_match(u32 secid, u32 field, u32 op, void *lsmrule)
5398 {
5399 	return call_int_hook(audit_rule_match, 0, secid, field, op, lsmrule);
5400 }
5401 #endif /* CONFIG_AUDIT */
5402 
5403 #ifdef CONFIG_BPF_SYSCALL
5404 /**
5405  * security_bpf() - Check if the bpf syscall operation is allowed
5406  * @cmd: command
5407  * @attr: bpf attribute
5408  * @size: size
5409  *
5410  * Do a initial check for all bpf syscalls after the attribute is copied into
5411  * the kernel. The actual security module can implement their own rules to
5412  * check the specific cmd they need.
5413  *
5414  * Return: Returns 0 if permission is granted.
5415  */
5416 int security_bpf(int cmd, union bpf_attr *attr, unsigned int size)
5417 {
5418 	return call_int_hook(bpf, 0, cmd, attr, size);
5419 }
5420 
5421 /**
5422  * security_bpf_map() - Check if access to a bpf map is allowed
5423  * @map: bpf map
5424  * @fmode: mode
5425  *
5426  * Do a check when the kernel generates and returns a file descriptor for eBPF
5427  * maps.
5428  *
5429  * Return: Returns 0 if permission is granted.
5430  */
5431 int security_bpf_map(struct bpf_map *map, fmode_t fmode)
5432 {
5433 	return call_int_hook(bpf_map, 0, map, fmode);
5434 }
5435 
5436 /**
5437  * security_bpf_prog() - Check if access to a bpf program is allowed
5438  * @prog: bpf program
5439  *
5440  * Do a check when the kernel generates and returns a file descriptor for eBPF
5441  * programs.
5442  *
5443  * Return: Returns 0 if permission is granted.
5444  */
5445 int security_bpf_prog(struct bpf_prog *prog)
5446 {
5447 	return call_int_hook(bpf_prog, 0, prog);
5448 }
5449 
5450 /**
5451  * security_bpf_map_alloc() - Allocate a bpf map LSM blob
5452  * @map: bpf map
5453  *
5454  * Initialize the security field inside bpf map.
5455  *
5456  * Return: Returns 0 on success, error on failure.
5457  */
5458 int security_bpf_map_alloc(struct bpf_map *map)
5459 {
5460 	return call_int_hook(bpf_map_alloc_security, 0, map);
5461 }
5462 
5463 /**
5464  * security_bpf_prog_alloc() - Allocate a bpf program LSM blob
5465  * @aux: bpf program aux info struct
5466  *
5467  * Initialize the security field inside bpf program.
5468  *
5469  * Return: Returns 0 on success, error on failure.
5470  */
5471 int security_bpf_prog_alloc(struct bpf_prog_aux *aux)
5472 {
5473 	return call_int_hook(bpf_prog_alloc_security, 0, aux);
5474 }
5475 
5476 /**
5477  * security_bpf_map_free() - Free a bpf map's LSM blob
5478  * @map: bpf map
5479  *
5480  * Clean up the security information stored inside bpf map.
5481  */
5482 void security_bpf_map_free(struct bpf_map *map)
5483 {
5484 	call_void_hook(bpf_map_free_security, map);
5485 }
5486 
5487 /**
5488  * security_bpf_prog_free() - Free a bpf program's LSM blob
5489  * @aux: bpf program aux info struct
5490  *
5491  * Clean up the security information stored inside bpf prog.
5492  */
5493 void security_bpf_prog_free(struct bpf_prog_aux *aux)
5494 {
5495 	call_void_hook(bpf_prog_free_security, aux);
5496 }
5497 #endif /* CONFIG_BPF_SYSCALL */
5498 
5499 /**
5500  * security_locked_down() - Check if a kernel feature is allowed
5501  * @what: requested kernel feature
5502  *
5503  * Determine whether a kernel feature that potentially enables arbitrary code
5504  * execution in kernel space should be permitted.
5505  *
5506  * Return: Returns 0 if permission is granted.
5507  */
5508 int security_locked_down(enum lockdown_reason what)
5509 {
5510 	return call_int_hook(locked_down, 0, what);
5511 }
5512 EXPORT_SYMBOL(security_locked_down);
5513 
5514 #ifdef CONFIG_PERF_EVENTS
5515 /**
5516  * security_perf_event_open() - Check if a perf event open is allowed
5517  * @attr: perf event attribute
5518  * @type: type of event
5519  *
5520  * Check whether the @type of perf_event_open syscall is allowed.
5521  *
5522  * Return: Returns 0 if permission is granted.
5523  */
5524 int security_perf_event_open(struct perf_event_attr *attr, int type)
5525 {
5526 	return call_int_hook(perf_event_open, 0, attr, type);
5527 }
5528 
5529 /**
5530  * security_perf_event_alloc() - Allocate a perf event LSM blob
5531  * @event: perf event
5532  *
5533  * Allocate and save perf_event security info.
5534  *
5535  * Return: Returns 0 on success, error on failure.
5536  */
5537 int security_perf_event_alloc(struct perf_event *event)
5538 {
5539 	return call_int_hook(perf_event_alloc, 0, event);
5540 }
5541 
5542 /**
5543  * security_perf_event_free() - Free a perf event LSM blob
5544  * @event: perf event
5545  *
5546  * Release (free) perf_event security info.
5547  */
5548 void security_perf_event_free(struct perf_event *event)
5549 {
5550 	call_void_hook(perf_event_free, event);
5551 }
5552 
5553 /**
5554  * security_perf_event_read() - Check if reading a perf event label is allowed
5555  * @event: perf event
5556  *
5557  * Read perf_event security info if allowed.
5558  *
5559  * Return: Returns 0 if permission is granted.
5560  */
5561 int security_perf_event_read(struct perf_event *event)
5562 {
5563 	return call_int_hook(perf_event_read, 0, event);
5564 }
5565 
5566 /**
5567  * security_perf_event_write() - Check if writing a perf event label is allowed
5568  * @event: perf event
5569  *
5570  * Write perf_event security info if allowed.
5571  *
5572  * Return: Returns 0 if permission is granted.
5573  */
5574 int security_perf_event_write(struct perf_event *event)
5575 {
5576 	return call_int_hook(perf_event_write, 0, event);
5577 }
5578 #endif /* CONFIG_PERF_EVENTS */
5579 
5580 #ifdef CONFIG_IO_URING
5581 /**
5582  * security_uring_override_creds() - Check if overriding creds is allowed
5583  * @new: new credentials
5584  *
5585  * Check if the current task, executing an io_uring operation, is allowed to
5586  * override it's credentials with @new.
5587  *
5588  * Return: Returns 0 if permission is granted.
5589  */
5590 int security_uring_override_creds(const struct cred *new)
5591 {
5592 	return call_int_hook(uring_override_creds, 0, new);
5593 }
5594 
5595 /**
5596  * security_uring_sqpoll() - Check if IORING_SETUP_SQPOLL is allowed
5597  *
5598  * Check whether the current task is allowed to spawn a io_uring polling thread
5599  * (IORING_SETUP_SQPOLL).
5600  *
5601  * Return: Returns 0 if permission is granted.
5602  */
5603 int security_uring_sqpoll(void)
5604 {
5605 	return call_int_hook(uring_sqpoll, 0);
5606 }
5607 
5608 /**
5609  * security_uring_cmd() - Check if a io_uring passthrough command is allowed
5610  * @ioucmd: command
5611  *
5612  * Check whether the file_operations uring_cmd is allowed to run.
5613  *
5614  * Return: Returns 0 if permission is granted.
5615  */
5616 int security_uring_cmd(struct io_uring_cmd *ioucmd)
5617 {
5618 	return call_int_hook(uring_cmd, 0, ioucmd);
5619 }
5620 #endif /* CONFIG_IO_URING */
5621