xref: /linux/security/security.c (revision 96f30c8f0aa9923aa39b30bcaefeacf88b490231)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Security plug functions
4  *
5  * Copyright (C) 2001 WireX Communications, Inc <chris@wirex.com>
6  * Copyright (C) 2001-2002 Greg Kroah-Hartman <greg@kroah.com>
7  * Copyright (C) 2001 Networks Associates Technology, Inc <ssmalley@nai.com>
8  * Copyright (C) 2016 Mellanox Technologies
9  * Copyright (C) 2023 Microsoft Corporation <paul@paul-moore.com>
10  */
11 
12 #define pr_fmt(fmt) "LSM: " fmt
13 
14 #include <linux/bpf.h>
15 #include <linux/capability.h>
16 #include <linux/dcache.h>
17 #include <linux/export.h>
18 #include <linux/init.h>
19 #include <linux/kernel.h>
20 #include <linux/kernel_read_file.h>
21 #include <linux/lsm_hooks.h>
22 #include <linux/fsnotify.h>
23 #include <linux/mman.h>
24 #include <linux/mount.h>
25 #include <linux/personality.h>
26 #include <linux/backing-dev.h>
27 #include <linux/string.h>
28 #include <linux/xattr.h>
29 #include <linux/msg.h>
30 #include <linux/overflow.h>
31 #include <net/flow.h>
32 
33 /* How many LSMs were built into the kernel? */
34 #define LSM_COUNT (__end_lsm_info - __start_lsm_info)
35 
36 /*
37  * How many LSMs are built into the kernel as determined at
38  * build time. Used to determine fixed array sizes.
39  * The capability module is accounted for by CONFIG_SECURITY
40  */
41 #define LSM_CONFIG_COUNT ( \
42 	(IS_ENABLED(CONFIG_SECURITY) ? 1 : 0) + \
43 	(IS_ENABLED(CONFIG_SECURITY_SELINUX) ? 1 : 0) + \
44 	(IS_ENABLED(CONFIG_SECURITY_SMACK) ? 1 : 0) + \
45 	(IS_ENABLED(CONFIG_SECURITY_TOMOYO) ? 1 : 0) + \
46 	(IS_ENABLED(CONFIG_SECURITY_APPARMOR) ? 1 : 0) + \
47 	(IS_ENABLED(CONFIG_SECURITY_YAMA) ? 1 : 0) + \
48 	(IS_ENABLED(CONFIG_SECURITY_LOADPIN) ? 1 : 0) + \
49 	(IS_ENABLED(CONFIG_SECURITY_SAFESETID) ? 1 : 0) + \
50 	(IS_ENABLED(CONFIG_SECURITY_LOCKDOWN_LSM) ? 1 : 0) + \
51 	(IS_ENABLED(CONFIG_BPF_LSM) ? 1 : 0) + \
52 	(IS_ENABLED(CONFIG_SECURITY_LANDLOCK) ? 1 : 0) + \
53 	(IS_ENABLED(CONFIG_IMA) ? 1 : 0) + \
54 	(IS_ENABLED(CONFIG_EVM) ? 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.  If @uctx is NULL
784  * simply calculate the required size to output via @utc_len and return
785  * success.
786  *
787  * Returns 0 on success, -E2BIG if userspace buffer is not large enough,
788  * -EFAULT on a copyout error, -ENOMEM if memory can't be allocated.
789  */
790 int lsm_fill_user_ctx(struct lsm_ctx __user *uctx, u32 *uctx_len,
791 		      void *val, size_t val_len,
792 		      u64 id, u64 flags)
793 {
794 	struct lsm_ctx *nctx = NULL;
795 	size_t nctx_len;
796 	int rc = 0;
797 
798 	nctx_len = ALIGN(struct_size(nctx, ctx, val_len), sizeof(void *));
799 	if (nctx_len > *uctx_len) {
800 		rc = -E2BIG;
801 		goto out;
802 	}
803 
804 	/* no buffer - return success/0 and set @uctx_len to the req size */
805 	if (!uctx)
806 		goto out;
807 
808 	nctx = kzalloc(nctx_len, GFP_KERNEL);
809 	if (nctx == NULL) {
810 		rc = -ENOMEM;
811 		goto out;
812 	}
813 	nctx->id = id;
814 	nctx->flags = flags;
815 	nctx->len = nctx_len;
816 	nctx->ctx_len = val_len;
817 	memcpy(nctx->ctx, val, val_len);
818 
819 	if (copy_to_user(uctx, nctx, nctx_len))
820 		rc = -EFAULT;
821 
822 out:
823 	kfree(nctx);
824 	*uctx_len = nctx_len;
825 	return rc;
826 }
827 
828 /*
829  * The default value of the LSM hook is defined in linux/lsm_hook_defs.h and
830  * can be accessed with:
831  *
832  *	LSM_RET_DEFAULT(<hook_name>)
833  *
834  * The macros below define static constants for the default value of each
835  * LSM hook.
836  */
837 #define LSM_RET_DEFAULT(NAME) (NAME##_default)
838 #define DECLARE_LSM_RET_DEFAULT_void(DEFAULT, NAME)
839 #define DECLARE_LSM_RET_DEFAULT_int(DEFAULT, NAME) \
840 	static const int __maybe_unused LSM_RET_DEFAULT(NAME) = (DEFAULT);
841 #define LSM_HOOK(RET, DEFAULT, NAME, ...) \
842 	DECLARE_LSM_RET_DEFAULT_##RET(DEFAULT, NAME)
843 
844 #include <linux/lsm_hook_defs.h>
845 #undef LSM_HOOK
846 
847 /*
848  * Hook list operation macros.
849  *
850  * call_void_hook:
851  *	This is a hook that does not return a value.
852  *
853  * call_int_hook:
854  *	This is a hook that returns a value.
855  */
856 
857 #define call_void_hook(FUNC, ...)				\
858 	do {							\
859 		struct security_hook_list *P;			\
860 								\
861 		hlist_for_each_entry(P, &security_hook_heads.FUNC, list) \
862 			P->hook.FUNC(__VA_ARGS__);		\
863 	} while (0)
864 
865 #define call_int_hook(FUNC, ...) ({				\
866 	int RC = LSM_RET_DEFAULT(FUNC);				\
867 	do {							\
868 		struct security_hook_list *P;			\
869 								\
870 		hlist_for_each_entry(P, &security_hook_heads.FUNC, list) { \
871 			RC = P->hook.FUNC(__VA_ARGS__);		\
872 			if (RC != LSM_RET_DEFAULT(FUNC))	\
873 				break;				\
874 		}						\
875 	} while (0);						\
876 	RC;							\
877 })
878 
879 /* Security operations */
880 
881 /**
882  * security_binder_set_context_mgr() - Check if becoming binder ctx mgr is ok
883  * @mgr: task credentials of current binder process
884  *
885  * Check whether @mgr is allowed to be the binder context manager.
886  *
887  * Return: Return 0 if permission is granted.
888  */
889 int security_binder_set_context_mgr(const struct cred *mgr)
890 {
891 	return call_int_hook(binder_set_context_mgr, mgr);
892 }
893 
894 /**
895  * security_binder_transaction() - Check if a binder transaction is allowed
896  * @from: sending process
897  * @to: receiving process
898  *
899  * Check whether @from is allowed to invoke a binder transaction call to @to.
900  *
901  * Return: Returns 0 if permission is granted.
902  */
903 int security_binder_transaction(const struct cred *from,
904 				const struct cred *to)
905 {
906 	return call_int_hook(binder_transaction, from, to);
907 }
908 
909 /**
910  * security_binder_transfer_binder() - Check if a binder transfer is allowed
911  * @from: sending process
912  * @to: receiving process
913  *
914  * Check whether @from is allowed to transfer a binder reference to @to.
915  *
916  * Return: Returns 0 if permission is granted.
917  */
918 int security_binder_transfer_binder(const struct cred *from,
919 				    const struct cred *to)
920 {
921 	return call_int_hook(binder_transfer_binder, from, to);
922 }
923 
924 /**
925  * security_binder_transfer_file() - Check if a binder file xfer is allowed
926  * @from: sending process
927  * @to: receiving process
928  * @file: file being transferred
929  *
930  * Check whether @from is allowed to transfer @file to @to.
931  *
932  * Return: Returns 0 if permission is granted.
933  */
934 int security_binder_transfer_file(const struct cred *from,
935 				  const struct cred *to, const struct file *file)
936 {
937 	return call_int_hook(binder_transfer_file, from, to, file);
938 }
939 
940 /**
941  * security_ptrace_access_check() - Check if tracing is allowed
942  * @child: target process
943  * @mode: PTRACE_MODE flags
944  *
945  * Check permission before allowing the current process to trace the @child
946  * process.  Security modules may also want to perform a process tracing check
947  * during an execve in the set_security or apply_creds hooks of tracing check
948  * during an execve in the bprm_set_creds hook of binprm_security_ops if the
949  * process is being traced and its security attributes would be changed by the
950  * execve.
951  *
952  * Return: Returns 0 if permission is granted.
953  */
954 int security_ptrace_access_check(struct task_struct *child, unsigned int mode)
955 {
956 	return call_int_hook(ptrace_access_check, child, mode);
957 }
958 
959 /**
960  * security_ptrace_traceme() - Check if tracing is allowed
961  * @parent: tracing process
962  *
963  * Check that the @parent process has sufficient permission to trace the
964  * current process before allowing the current process to present itself to the
965  * @parent process for tracing.
966  *
967  * Return: Returns 0 if permission is granted.
968  */
969 int security_ptrace_traceme(struct task_struct *parent)
970 {
971 	return call_int_hook(ptrace_traceme, parent);
972 }
973 
974 /**
975  * security_capget() - Get the capability sets for a process
976  * @target: target process
977  * @effective: effective capability set
978  * @inheritable: inheritable capability set
979  * @permitted: permitted capability set
980  *
981  * Get the @effective, @inheritable, and @permitted capability sets for the
982  * @target process.  The hook may also perform permission checking to determine
983  * if the current process is allowed to see the capability sets of the @target
984  * process.
985  *
986  * Return: Returns 0 if the capability sets were successfully obtained.
987  */
988 int security_capget(const struct task_struct *target,
989 		    kernel_cap_t *effective,
990 		    kernel_cap_t *inheritable,
991 		    kernel_cap_t *permitted)
992 {
993 	return call_int_hook(capget, target, effective, inheritable, permitted);
994 }
995 
996 /**
997  * security_capset() - Set the capability sets for a process
998  * @new: new credentials for the target process
999  * @old: current credentials of the target process
1000  * @effective: effective capability set
1001  * @inheritable: inheritable capability set
1002  * @permitted: permitted capability set
1003  *
1004  * Set the @effective, @inheritable, and @permitted capability sets for the
1005  * current process.
1006  *
1007  * Return: Returns 0 and update @new if permission is granted.
1008  */
1009 int security_capset(struct cred *new, const struct cred *old,
1010 		    const kernel_cap_t *effective,
1011 		    const kernel_cap_t *inheritable,
1012 		    const kernel_cap_t *permitted)
1013 {
1014 	return call_int_hook(capset, new, old, effective, inheritable,
1015 			     permitted);
1016 }
1017 
1018 /**
1019  * security_capable() - Check if a process has the necessary capability
1020  * @cred: credentials to examine
1021  * @ns: user namespace
1022  * @cap: capability requested
1023  * @opts: capability check options
1024  *
1025  * Check whether the @tsk process has the @cap capability in the indicated
1026  * credentials.  @cap contains the capability <include/linux/capability.h>.
1027  * @opts contains options for the capable check <include/linux/security.h>.
1028  *
1029  * Return: Returns 0 if the capability is granted.
1030  */
1031 int security_capable(const struct cred *cred,
1032 		     struct user_namespace *ns,
1033 		     int cap,
1034 		     unsigned int opts)
1035 {
1036 	return call_int_hook(capable, cred, ns, cap, opts);
1037 }
1038 
1039 /**
1040  * security_quotactl() - Check if a quotactl() syscall is allowed for this fs
1041  * @cmds: commands
1042  * @type: type
1043  * @id: id
1044  * @sb: filesystem
1045  *
1046  * Check whether the quotactl syscall is allowed for this @sb.
1047  *
1048  * Return: Returns 0 if permission is granted.
1049  */
1050 int security_quotactl(int cmds, int type, int id, const struct super_block *sb)
1051 {
1052 	return call_int_hook(quotactl, cmds, type, id, sb);
1053 }
1054 
1055 /**
1056  * security_quota_on() - Check if QUOTAON is allowed for a dentry
1057  * @dentry: dentry
1058  *
1059  * Check whether QUOTAON is allowed for @dentry.
1060  *
1061  * Return: Returns 0 if permission is granted.
1062  */
1063 int security_quota_on(struct dentry *dentry)
1064 {
1065 	return call_int_hook(quota_on, dentry);
1066 }
1067 
1068 /**
1069  * security_syslog() - Check if accessing the kernel message ring is allowed
1070  * @type: SYSLOG_ACTION_* type
1071  *
1072  * Check permission before accessing the kernel message ring or changing
1073  * logging to the console.  See the syslog(2) manual page for an explanation of
1074  * the @type values.
1075  *
1076  * Return: Return 0 if permission is granted.
1077  */
1078 int security_syslog(int type)
1079 {
1080 	return call_int_hook(syslog, type);
1081 }
1082 
1083 /**
1084  * security_settime64() - Check if changing the system time is allowed
1085  * @ts: new time
1086  * @tz: timezone
1087  *
1088  * Check permission to change the system time, struct timespec64 is defined in
1089  * <include/linux/time64.h> and timezone is defined in <include/linux/time.h>.
1090  *
1091  * Return: Returns 0 if permission is granted.
1092  */
1093 int security_settime64(const struct timespec64 *ts, const struct timezone *tz)
1094 {
1095 	return call_int_hook(settime, ts, tz);
1096 }
1097 
1098 /**
1099  * security_vm_enough_memory_mm() - Check if allocating a new mem map is allowed
1100  * @mm: mm struct
1101  * @pages: number of pages
1102  *
1103  * Check permissions for allocating a new virtual mapping.  If all LSMs return
1104  * a positive value, __vm_enough_memory() will be called with cap_sys_admin
1105  * set. If at least one LSM returns 0 or negative, __vm_enough_memory() will be
1106  * called with cap_sys_admin cleared.
1107  *
1108  * Return: Returns 0 if permission is granted by the LSM infrastructure to the
1109  *         caller.
1110  */
1111 int security_vm_enough_memory_mm(struct mm_struct *mm, long pages)
1112 {
1113 	struct security_hook_list *hp;
1114 	int cap_sys_admin = 1;
1115 	int rc;
1116 
1117 	/*
1118 	 * The module will respond with a positive value if
1119 	 * it thinks the __vm_enough_memory() call should be
1120 	 * made with the cap_sys_admin set. If all of the modules
1121 	 * agree that it should be set it will. If any module
1122 	 * thinks it should not be set it won't.
1123 	 */
1124 	hlist_for_each_entry(hp, &security_hook_heads.vm_enough_memory, list) {
1125 		rc = hp->hook.vm_enough_memory(mm, pages);
1126 		if (rc <= 0) {
1127 			cap_sys_admin = 0;
1128 			break;
1129 		}
1130 	}
1131 	return __vm_enough_memory(mm, pages, cap_sys_admin);
1132 }
1133 
1134 /**
1135  * security_bprm_creds_for_exec() - Prepare the credentials for exec()
1136  * @bprm: binary program information
1137  *
1138  * If the setup in prepare_exec_creds did not setup @bprm->cred->security
1139  * properly for executing @bprm->file, update the LSM's portion of
1140  * @bprm->cred->security to be what commit_creds needs to install for the new
1141  * program.  This hook may also optionally check permissions (e.g. for
1142  * transitions between security domains).  The hook must set @bprm->secureexec
1143  * to 1 if AT_SECURE should be set to request libc enable secure mode.  @bprm
1144  * contains the linux_binprm structure.
1145  *
1146  * Return: Returns 0 if the hook is successful and permission is granted.
1147  */
1148 int security_bprm_creds_for_exec(struct linux_binprm *bprm)
1149 {
1150 	return call_int_hook(bprm_creds_for_exec, bprm);
1151 }
1152 
1153 /**
1154  * security_bprm_creds_from_file() - Update linux_binprm creds based on file
1155  * @bprm: binary program information
1156  * @file: associated file
1157  *
1158  * If @file is setpcap, suid, sgid or otherwise marked to change privilege upon
1159  * exec, update @bprm->cred to reflect that change. This is called after
1160  * finding the binary that will be executed without an interpreter.  This
1161  * ensures that the credentials will not be derived from a script that the
1162  * binary will need to reopen, which when reopend may end up being a completely
1163  * different file.  This hook may also optionally check permissions (e.g. for
1164  * transitions between security domains).  The hook must set @bprm->secureexec
1165  * to 1 if AT_SECURE should be set to request libc enable secure mode.  The
1166  * hook must add to @bprm->per_clear any personality flags that should be
1167  * cleared from current->personality.  @bprm contains the linux_binprm
1168  * structure.
1169  *
1170  * Return: Returns 0 if the hook is successful and permission is granted.
1171  */
1172 int security_bprm_creds_from_file(struct linux_binprm *bprm, const struct file *file)
1173 {
1174 	return call_int_hook(bprm_creds_from_file, bprm, file);
1175 }
1176 
1177 /**
1178  * security_bprm_check() - Mediate binary handler search
1179  * @bprm: binary program information
1180  *
1181  * This hook mediates the point when a search for a binary handler will begin.
1182  * It allows a check against the @bprm->cred->security value which was set in
1183  * the preceding creds_for_exec call.  The argv list and envp list are reliably
1184  * available in @bprm.  This hook may be called multiple times during a single
1185  * execve.  @bprm contains the linux_binprm structure.
1186  *
1187  * Return: Returns 0 if the hook is successful and permission is granted.
1188  */
1189 int security_bprm_check(struct linux_binprm *bprm)
1190 {
1191 	return call_int_hook(bprm_check_security, 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, 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, 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, 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, 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, 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, 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, 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, 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, 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, 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, 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, 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 	struct security_hook_list *hp;
1509 	int rc = mnt_opts ? -EOPNOTSUPP : LSM_RET_DEFAULT(sb_set_mnt_opts);
1510 
1511 	hlist_for_each_entry(hp, &security_hook_heads.sb_set_mnt_opts,
1512 			     list) {
1513 		rc = hp->hook.sb_set_mnt_opts(sb, mnt_opts, kern_flags,
1514 					      set_kern_flags);
1515 		if (rc != LSM_RET_DEFAULT(sb_set_mnt_opts))
1516 			break;
1517 	}
1518 	return rc;
1519 }
1520 EXPORT_SYMBOL(security_sb_set_mnt_opts);
1521 
1522 /**
1523  * security_sb_clone_mnt_opts() - Duplicate superblock mount options
1524  * @oldsb: source superblock
1525  * @newsb: destination superblock
1526  * @kern_flags: kernel flags (in)
1527  * @set_kern_flags: kernel flags (out)
1528  *
1529  * Copy all security options from a given superblock to another.
1530  *
1531  * Return: Returns 0 on success, error on failure.
1532  */
1533 int security_sb_clone_mnt_opts(const struct super_block *oldsb,
1534 			       struct super_block *newsb,
1535 			       unsigned long kern_flags,
1536 			       unsigned long *set_kern_flags)
1537 {
1538 	return call_int_hook(sb_clone_mnt_opts, oldsb, newsb,
1539 			     kern_flags, set_kern_flags);
1540 }
1541 EXPORT_SYMBOL(security_sb_clone_mnt_opts);
1542 
1543 /**
1544  * security_move_mount() - Check permissions for moving a mount
1545  * @from_path: source mount point
1546  * @to_path: destination mount point
1547  *
1548  * Check permission before a mount is moved.
1549  *
1550  * Return: Returns 0 if permission is granted.
1551  */
1552 int security_move_mount(const struct path *from_path,
1553 			const struct path *to_path)
1554 {
1555 	return call_int_hook(move_mount, from_path, to_path);
1556 }
1557 
1558 /**
1559  * security_path_notify() - Check if setting a watch is allowed
1560  * @path: file path
1561  * @mask: event mask
1562  * @obj_type: file path type
1563  *
1564  * Check permissions before setting a watch on events as defined by @mask, on
1565  * an object at @path, whose type is defined by @obj_type.
1566  *
1567  * Return: Returns 0 if permission is granted.
1568  */
1569 int security_path_notify(const struct path *path, u64 mask,
1570 			 unsigned int obj_type)
1571 {
1572 	return call_int_hook(path_notify, path, mask, obj_type);
1573 }
1574 
1575 /**
1576  * security_inode_alloc() - Allocate an inode LSM blob
1577  * @inode: the inode
1578  *
1579  * Allocate and attach a security structure to @inode->i_security.  The
1580  * i_security field is initialized to NULL when the inode structure is
1581  * allocated.
1582  *
1583  * Return: Return 0 if operation was successful.
1584  */
1585 int security_inode_alloc(struct inode *inode)
1586 {
1587 	int rc = lsm_inode_alloc(inode);
1588 
1589 	if (unlikely(rc))
1590 		return rc;
1591 	rc = call_int_hook(inode_alloc_security, inode);
1592 	if (unlikely(rc))
1593 		security_inode_free(inode);
1594 	return rc;
1595 }
1596 
1597 static void inode_free_by_rcu(struct rcu_head *head)
1598 {
1599 	/*
1600 	 * The rcu head is at the start of the inode blob
1601 	 */
1602 	kmem_cache_free(lsm_inode_cache, head);
1603 }
1604 
1605 /**
1606  * security_inode_free() - Free an inode's LSM blob
1607  * @inode: the inode
1608  *
1609  * Deallocate the inode security structure and set @inode->i_security to NULL.
1610  */
1611 void security_inode_free(struct inode *inode)
1612 {
1613 	call_void_hook(inode_free_security, inode);
1614 	/*
1615 	 * The inode may still be referenced in a path walk and
1616 	 * a call to security_inode_permission() can be made
1617 	 * after inode_free_security() is called. Ideally, the VFS
1618 	 * wouldn't do this, but fixing that is a much harder
1619 	 * job. For now, simply free the i_security via RCU, and
1620 	 * leave the current inode->i_security pointer intact.
1621 	 * The inode will be freed after the RCU grace period too.
1622 	 */
1623 	if (inode->i_security)
1624 		call_rcu((struct rcu_head *)inode->i_security,
1625 			 inode_free_by_rcu);
1626 }
1627 
1628 /**
1629  * security_dentry_init_security() - Perform dentry initialization
1630  * @dentry: the dentry to initialize
1631  * @mode: mode used to determine resource type
1632  * @name: name of the last path component
1633  * @xattr_name: name of the security/LSM xattr
1634  * @ctx: pointer to the resulting LSM context
1635  * @ctxlen: length of @ctx
1636  *
1637  * Compute a context for a dentry as the inode is not yet available since NFSv4
1638  * has no label backed by an EA anyway.  It is important to note that
1639  * @xattr_name does not need to be free'd by the caller, it is a static string.
1640  *
1641  * Return: Returns 0 on success, negative values on failure.
1642  */
1643 int security_dentry_init_security(struct dentry *dentry, int mode,
1644 				  const struct qstr *name,
1645 				  const char **xattr_name, void **ctx,
1646 				  u32 *ctxlen)
1647 {
1648 	return call_int_hook(dentry_init_security, dentry, mode, name,
1649 			     xattr_name, ctx, ctxlen);
1650 }
1651 EXPORT_SYMBOL(security_dentry_init_security);
1652 
1653 /**
1654  * security_dentry_create_files_as() - Perform dentry initialization
1655  * @dentry: the dentry to initialize
1656  * @mode: mode used to determine resource type
1657  * @name: name of the last path component
1658  * @old: creds to use for LSM context calculations
1659  * @new: creds to modify
1660  *
1661  * Compute a context for a dentry as the inode is not yet available and set
1662  * that context in passed in creds so that new files are created using that
1663  * context. Context is calculated using the passed in creds and not the creds
1664  * of the caller.
1665  *
1666  * Return: Returns 0 on success, error on failure.
1667  */
1668 int security_dentry_create_files_as(struct dentry *dentry, int mode,
1669 				    struct qstr *name,
1670 				    const struct cred *old, struct cred *new)
1671 {
1672 	return call_int_hook(dentry_create_files_as, dentry, mode,
1673 			     name, old, new);
1674 }
1675 EXPORT_SYMBOL(security_dentry_create_files_as);
1676 
1677 /**
1678  * security_inode_init_security() - Initialize an inode's LSM context
1679  * @inode: the inode
1680  * @dir: parent directory
1681  * @qstr: last component of the pathname
1682  * @initxattrs: callback function to write xattrs
1683  * @fs_data: filesystem specific data
1684  *
1685  * Obtain the security attribute name suffix and value to set on a newly
1686  * created inode and set up the incore security field for the new inode.  This
1687  * hook is called by the fs code as part of the inode creation transaction and
1688  * provides for atomic labeling of the inode, unlike the post_create/mkdir/...
1689  * hooks called by the VFS.
1690  *
1691  * The hook function is expected to populate the xattrs array, by calling
1692  * lsm_get_xattr_slot() to retrieve the slots reserved by the security module
1693  * with the lbs_xattr_count field of the lsm_blob_sizes structure.  For each
1694  * slot, the hook function should set ->name to the attribute name suffix
1695  * (e.g. selinux), to allocate ->value (will be freed by the caller) and set it
1696  * to the attribute value, to set ->value_len to the length of the value.  If
1697  * the security module does not use security attributes or does not wish to put
1698  * a security attribute on this particular inode, then it should return
1699  * -EOPNOTSUPP to skip this processing.
1700  *
1701  * Return: Returns 0 if the LSM successfully initialized all of the inode
1702  *         security attributes that are required, negative values otherwise.
1703  */
1704 int security_inode_init_security(struct inode *inode, struct inode *dir,
1705 				 const struct qstr *qstr,
1706 				 const initxattrs initxattrs, void *fs_data)
1707 {
1708 	struct security_hook_list *hp;
1709 	struct xattr *new_xattrs = NULL;
1710 	int ret = -EOPNOTSUPP, xattr_count = 0;
1711 
1712 	if (unlikely(IS_PRIVATE(inode)))
1713 		return 0;
1714 
1715 	if (!blob_sizes.lbs_xattr_count)
1716 		return 0;
1717 
1718 	if (initxattrs) {
1719 		/* Allocate +1 as terminator. */
1720 		new_xattrs = kcalloc(blob_sizes.lbs_xattr_count + 1,
1721 				     sizeof(*new_xattrs), GFP_NOFS);
1722 		if (!new_xattrs)
1723 			return -ENOMEM;
1724 	}
1725 
1726 	hlist_for_each_entry(hp, &security_hook_heads.inode_init_security,
1727 			     list) {
1728 		ret = hp->hook.inode_init_security(inode, dir, qstr, new_xattrs,
1729 						  &xattr_count);
1730 		if (ret && ret != -EOPNOTSUPP)
1731 			goto out;
1732 		/*
1733 		 * As documented in lsm_hooks.h, -EOPNOTSUPP in this context
1734 		 * means that the LSM is not willing to provide an xattr, not
1735 		 * that it wants to signal an error. Thus, continue to invoke
1736 		 * the remaining LSMs.
1737 		 */
1738 	}
1739 
1740 	/* If initxattrs() is NULL, xattr_count is zero, skip the call. */
1741 	if (!xattr_count)
1742 		goto out;
1743 
1744 	ret = initxattrs(inode, new_xattrs, fs_data);
1745 out:
1746 	for (; xattr_count > 0; xattr_count--)
1747 		kfree(new_xattrs[xattr_count - 1].value);
1748 	kfree(new_xattrs);
1749 	return (ret == -EOPNOTSUPP) ? 0 : ret;
1750 }
1751 EXPORT_SYMBOL(security_inode_init_security);
1752 
1753 /**
1754  * security_inode_init_security_anon() - Initialize an anonymous inode
1755  * @inode: the inode
1756  * @name: the anonymous inode class
1757  * @context_inode: an optional related inode
1758  *
1759  * Set up the incore security field for the new anonymous inode and return
1760  * whether the inode creation is permitted by the security module or not.
1761  *
1762  * Return: Returns 0 on success, -EACCES if the security module denies the
1763  * creation of this inode, or another -errno upon other errors.
1764  */
1765 int security_inode_init_security_anon(struct inode *inode,
1766 				      const struct qstr *name,
1767 				      const struct inode *context_inode)
1768 {
1769 	return call_int_hook(inode_init_security_anon, inode, name,
1770 			     context_inode);
1771 }
1772 
1773 #ifdef CONFIG_SECURITY_PATH
1774 /**
1775  * security_path_mknod() - Check if creating a special file is allowed
1776  * @dir: parent directory
1777  * @dentry: new file
1778  * @mode: new file mode
1779  * @dev: device number
1780  *
1781  * Check permissions when creating a file. Note that this hook is called even
1782  * if mknod operation is being done for a regular file.
1783  *
1784  * Return: Returns 0 if permission is granted.
1785  */
1786 int security_path_mknod(const struct path *dir, struct dentry *dentry,
1787 			umode_t mode, unsigned int dev)
1788 {
1789 	if (unlikely(IS_PRIVATE(d_backing_inode(dir->dentry))))
1790 		return 0;
1791 	return call_int_hook(path_mknod, dir, dentry, mode, dev);
1792 }
1793 EXPORT_SYMBOL(security_path_mknod);
1794 
1795 /**
1796  * security_path_post_mknod() - Update inode security after reg file creation
1797  * @idmap: idmap of the mount
1798  * @dentry: new file
1799  *
1800  * Update inode security field after a regular file has been created.
1801  */
1802 void security_path_post_mknod(struct mnt_idmap *idmap, struct dentry *dentry)
1803 {
1804 	if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
1805 		return;
1806 	call_void_hook(path_post_mknod, idmap, dentry);
1807 }
1808 
1809 /**
1810  * security_path_mkdir() - Check if creating a new directory is allowed
1811  * @dir: parent directory
1812  * @dentry: new directory
1813  * @mode: new directory mode
1814  *
1815  * Check permissions to create a new directory in the existing directory.
1816  *
1817  * Return: Returns 0 if permission is granted.
1818  */
1819 int security_path_mkdir(const struct path *dir, struct dentry *dentry,
1820 			umode_t mode)
1821 {
1822 	if (unlikely(IS_PRIVATE(d_backing_inode(dir->dentry))))
1823 		return 0;
1824 	return call_int_hook(path_mkdir, dir, dentry, mode);
1825 }
1826 EXPORT_SYMBOL(security_path_mkdir);
1827 
1828 /**
1829  * security_path_rmdir() - Check if removing a directory is allowed
1830  * @dir: parent directory
1831  * @dentry: directory to remove
1832  *
1833  * Check the permission to remove a directory.
1834  *
1835  * Return: Returns 0 if permission is granted.
1836  */
1837 int security_path_rmdir(const struct path *dir, struct dentry *dentry)
1838 {
1839 	if (unlikely(IS_PRIVATE(d_backing_inode(dir->dentry))))
1840 		return 0;
1841 	return call_int_hook(path_rmdir, dir, dentry);
1842 }
1843 
1844 /**
1845  * security_path_unlink() - Check if removing a hard link is allowed
1846  * @dir: parent directory
1847  * @dentry: file
1848  *
1849  * Check the permission to remove a hard link to a file.
1850  *
1851  * Return: Returns 0 if permission is granted.
1852  */
1853 int security_path_unlink(const struct path *dir, struct dentry *dentry)
1854 {
1855 	if (unlikely(IS_PRIVATE(d_backing_inode(dir->dentry))))
1856 		return 0;
1857 	return call_int_hook(path_unlink, dir, dentry);
1858 }
1859 EXPORT_SYMBOL(security_path_unlink);
1860 
1861 /**
1862  * security_path_symlink() - Check if creating a symbolic link is allowed
1863  * @dir: parent directory
1864  * @dentry: symbolic link
1865  * @old_name: file pathname
1866  *
1867  * Check the permission to create a symbolic link to a file.
1868  *
1869  * Return: Returns 0 if permission is granted.
1870  */
1871 int security_path_symlink(const struct path *dir, struct dentry *dentry,
1872 			  const char *old_name)
1873 {
1874 	if (unlikely(IS_PRIVATE(d_backing_inode(dir->dentry))))
1875 		return 0;
1876 	return call_int_hook(path_symlink, dir, dentry, old_name);
1877 }
1878 
1879 /**
1880  * security_path_link - Check if creating a hard link is allowed
1881  * @old_dentry: existing file
1882  * @new_dir: new parent directory
1883  * @new_dentry: new link
1884  *
1885  * Check permission before creating a new hard link to a file.
1886  *
1887  * Return: Returns 0 if permission is granted.
1888  */
1889 int security_path_link(struct dentry *old_dentry, const struct path *new_dir,
1890 		       struct dentry *new_dentry)
1891 {
1892 	if (unlikely(IS_PRIVATE(d_backing_inode(old_dentry))))
1893 		return 0;
1894 	return call_int_hook(path_link, old_dentry, new_dir, new_dentry);
1895 }
1896 
1897 /**
1898  * security_path_rename() - Check if renaming a file is allowed
1899  * @old_dir: parent directory of the old file
1900  * @old_dentry: the old file
1901  * @new_dir: parent directory of the new file
1902  * @new_dentry: the new file
1903  * @flags: flags
1904  *
1905  * Check for permission to rename a file or directory.
1906  *
1907  * Return: Returns 0 if permission is granted.
1908  */
1909 int security_path_rename(const struct path *old_dir, struct dentry *old_dentry,
1910 			 const struct path *new_dir, struct dentry *new_dentry,
1911 			 unsigned int flags)
1912 {
1913 	if (unlikely(IS_PRIVATE(d_backing_inode(old_dentry)) ||
1914 		     (d_is_positive(new_dentry) &&
1915 		      IS_PRIVATE(d_backing_inode(new_dentry)))))
1916 		return 0;
1917 
1918 	return call_int_hook(path_rename, old_dir, old_dentry, new_dir,
1919 			     new_dentry, flags);
1920 }
1921 EXPORT_SYMBOL(security_path_rename);
1922 
1923 /**
1924  * security_path_truncate() - Check if truncating a file is allowed
1925  * @path: file
1926  *
1927  * Check permission before truncating the file indicated by path.  Note that
1928  * truncation permissions may also be checked based on already opened files,
1929  * using the security_file_truncate() hook.
1930  *
1931  * Return: Returns 0 if permission is granted.
1932  */
1933 int security_path_truncate(const struct path *path)
1934 {
1935 	if (unlikely(IS_PRIVATE(d_backing_inode(path->dentry))))
1936 		return 0;
1937 	return call_int_hook(path_truncate, path);
1938 }
1939 
1940 /**
1941  * security_path_chmod() - Check if changing the file's mode is allowed
1942  * @path: file
1943  * @mode: new mode
1944  *
1945  * Check for permission to change a mode of the file @path. The new mode is
1946  * specified in @mode which is a bitmask of constants from
1947  * <include/uapi/linux/stat.h>.
1948  *
1949  * Return: Returns 0 if permission is granted.
1950  */
1951 int security_path_chmod(const struct path *path, umode_t mode)
1952 {
1953 	if (unlikely(IS_PRIVATE(d_backing_inode(path->dentry))))
1954 		return 0;
1955 	return call_int_hook(path_chmod, path, mode);
1956 }
1957 
1958 /**
1959  * security_path_chown() - Check if changing the file's owner/group is allowed
1960  * @path: file
1961  * @uid: file owner
1962  * @gid: file group
1963  *
1964  * Check for permission to change owner/group of a file or directory.
1965  *
1966  * Return: Returns 0 if permission is granted.
1967  */
1968 int security_path_chown(const struct path *path, kuid_t uid, kgid_t gid)
1969 {
1970 	if (unlikely(IS_PRIVATE(d_backing_inode(path->dentry))))
1971 		return 0;
1972 	return call_int_hook(path_chown, path, uid, gid);
1973 }
1974 
1975 /**
1976  * security_path_chroot() - Check if changing the root directory is allowed
1977  * @path: directory
1978  *
1979  * Check for permission to change root directory.
1980  *
1981  * Return: Returns 0 if permission is granted.
1982  */
1983 int security_path_chroot(const struct path *path)
1984 {
1985 	return call_int_hook(path_chroot, path);
1986 }
1987 #endif /* CONFIG_SECURITY_PATH */
1988 
1989 /**
1990  * security_inode_create() - Check if creating a file is allowed
1991  * @dir: the parent directory
1992  * @dentry: the file being created
1993  * @mode: requested file mode
1994  *
1995  * Check permission to create a regular file.
1996  *
1997  * Return: Returns 0 if permission is granted.
1998  */
1999 int security_inode_create(struct inode *dir, struct dentry *dentry,
2000 			  umode_t mode)
2001 {
2002 	if (unlikely(IS_PRIVATE(dir)))
2003 		return 0;
2004 	return call_int_hook(inode_create, dir, dentry, mode);
2005 }
2006 EXPORT_SYMBOL_GPL(security_inode_create);
2007 
2008 /**
2009  * security_inode_post_create_tmpfile() - Update inode security of new tmpfile
2010  * @idmap: idmap of the mount
2011  * @inode: inode of the new tmpfile
2012  *
2013  * Update inode security data after a tmpfile has been created.
2014  */
2015 void security_inode_post_create_tmpfile(struct mnt_idmap *idmap,
2016 					struct inode *inode)
2017 {
2018 	if (unlikely(IS_PRIVATE(inode)))
2019 		return;
2020 	call_void_hook(inode_post_create_tmpfile, idmap, inode);
2021 }
2022 
2023 /**
2024  * security_inode_link() - Check if creating a hard link is allowed
2025  * @old_dentry: existing file
2026  * @dir: new parent directory
2027  * @new_dentry: new link
2028  *
2029  * Check permission before creating a new hard link to a file.
2030  *
2031  * Return: Returns 0 if permission is granted.
2032  */
2033 int security_inode_link(struct dentry *old_dentry, struct inode *dir,
2034 			struct dentry *new_dentry)
2035 {
2036 	if (unlikely(IS_PRIVATE(d_backing_inode(old_dentry))))
2037 		return 0;
2038 	return call_int_hook(inode_link, old_dentry, dir, new_dentry);
2039 }
2040 
2041 /**
2042  * security_inode_unlink() - Check if removing a hard link is allowed
2043  * @dir: parent directory
2044  * @dentry: file
2045  *
2046  * Check the permission to remove a hard link to a file.
2047  *
2048  * Return: Returns 0 if permission is granted.
2049  */
2050 int security_inode_unlink(struct inode *dir, struct dentry *dentry)
2051 {
2052 	if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
2053 		return 0;
2054 	return call_int_hook(inode_unlink, dir, dentry);
2055 }
2056 
2057 /**
2058  * security_inode_symlink() - Check if creating a symbolic link is allowed
2059  * @dir: parent directory
2060  * @dentry: symbolic link
2061  * @old_name: existing filename
2062  *
2063  * Check the permission to create a symbolic link to a file.
2064  *
2065  * Return: Returns 0 if permission is granted.
2066  */
2067 int security_inode_symlink(struct inode *dir, struct dentry *dentry,
2068 			   const char *old_name)
2069 {
2070 	if (unlikely(IS_PRIVATE(dir)))
2071 		return 0;
2072 	return call_int_hook(inode_symlink, dir, dentry, old_name);
2073 }
2074 
2075 /**
2076  * security_inode_mkdir() - Check if creation a new director is allowed
2077  * @dir: parent directory
2078  * @dentry: new directory
2079  * @mode: new directory mode
2080  *
2081  * Check permissions to create a new directory in the existing directory
2082  * associated with inode structure @dir.
2083  *
2084  * Return: Returns 0 if permission is granted.
2085  */
2086 int security_inode_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
2087 {
2088 	if (unlikely(IS_PRIVATE(dir)))
2089 		return 0;
2090 	return call_int_hook(inode_mkdir, dir, dentry, mode);
2091 }
2092 EXPORT_SYMBOL_GPL(security_inode_mkdir);
2093 
2094 /**
2095  * security_inode_rmdir() - Check if removing a directory is allowed
2096  * @dir: parent directory
2097  * @dentry: directory to be removed
2098  *
2099  * Check the permission to remove a directory.
2100  *
2101  * Return: Returns 0 if permission is granted.
2102  */
2103 int security_inode_rmdir(struct inode *dir, struct dentry *dentry)
2104 {
2105 	if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
2106 		return 0;
2107 	return call_int_hook(inode_rmdir, dir, dentry);
2108 }
2109 
2110 /**
2111  * security_inode_mknod() - Check if creating a special file is allowed
2112  * @dir: parent directory
2113  * @dentry: new file
2114  * @mode: new file mode
2115  * @dev: device number
2116  *
2117  * Check permissions when creating a special file (or a socket or a fifo file
2118  * created via the mknod system call).  Note that if mknod operation is being
2119  * done for a regular file, then the create hook will be called and not this
2120  * hook.
2121  *
2122  * Return: Returns 0 if permission is granted.
2123  */
2124 int security_inode_mknod(struct inode *dir, struct dentry *dentry,
2125 			 umode_t mode, dev_t dev)
2126 {
2127 	if (unlikely(IS_PRIVATE(dir)))
2128 		return 0;
2129 	return call_int_hook(inode_mknod, dir, dentry, mode, dev);
2130 }
2131 
2132 /**
2133  * security_inode_rename() - Check if renaming a file is allowed
2134  * @old_dir: parent directory of the old file
2135  * @old_dentry: the old file
2136  * @new_dir: parent directory of the new file
2137  * @new_dentry: the new file
2138  * @flags: flags
2139  *
2140  * Check for permission to rename a file or directory.
2141  *
2142  * Return: Returns 0 if permission is granted.
2143  */
2144 int security_inode_rename(struct inode *old_dir, struct dentry *old_dentry,
2145 			  struct inode *new_dir, struct dentry *new_dentry,
2146 			  unsigned int flags)
2147 {
2148 	if (unlikely(IS_PRIVATE(d_backing_inode(old_dentry)) ||
2149 		     (d_is_positive(new_dentry) &&
2150 		      IS_PRIVATE(d_backing_inode(new_dentry)))))
2151 		return 0;
2152 
2153 	if (flags & RENAME_EXCHANGE) {
2154 		int err = call_int_hook(inode_rename, new_dir, new_dentry,
2155 					old_dir, old_dentry);
2156 		if (err)
2157 			return err;
2158 	}
2159 
2160 	return call_int_hook(inode_rename, old_dir, old_dentry,
2161 			     new_dir, new_dentry);
2162 }
2163 
2164 /**
2165  * security_inode_readlink() - Check if reading a symbolic link is allowed
2166  * @dentry: link
2167  *
2168  * Check the permission to read the symbolic link.
2169  *
2170  * Return: Returns 0 if permission is granted.
2171  */
2172 int security_inode_readlink(struct dentry *dentry)
2173 {
2174 	if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
2175 		return 0;
2176 	return call_int_hook(inode_readlink, dentry);
2177 }
2178 
2179 /**
2180  * security_inode_follow_link() - Check if following a symbolic link is allowed
2181  * @dentry: link dentry
2182  * @inode: link inode
2183  * @rcu: true if in RCU-walk mode
2184  *
2185  * Check permission to follow a symbolic link when looking up a pathname.  If
2186  * @rcu is true, @inode is not stable.
2187  *
2188  * Return: Returns 0 if permission is granted.
2189  */
2190 int security_inode_follow_link(struct dentry *dentry, struct inode *inode,
2191 			       bool rcu)
2192 {
2193 	if (unlikely(IS_PRIVATE(inode)))
2194 		return 0;
2195 	return call_int_hook(inode_follow_link, dentry, inode, rcu);
2196 }
2197 
2198 /**
2199  * security_inode_permission() - Check if accessing an inode is allowed
2200  * @inode: inode
2201  * @mask: access mask
2202  *
2203  * Check permission before accessing an inode.  This hook is called by the
2204  * existing Linux permission function, so a security module can use it to
2205  * provide additional checking for existing Linux permission checks.  Notice
2206  * that this hook is called when a file is opened (as well as many other
2207  * operations), whereas the file_security_ops permission hook is called when
2208  * the actual read/write operations are performed.
2209  *
2210  * Return: Returns 0 if permission is granted.
2211  */
2212 int security_inode_permission(struct inode *inode, int mask)
2213 {
2214 	if (unlikely(IS_PRIVATE(inode)))
2215 		return 0;
2216 	return call_int_hook(inode_permission, inode, mask);
2217 }
2218 
2219 /**
2220  * security_inode_setattr() - Check if setting file attributes is allowed
2221  * @idmap: idmap of the mount
2222  * @dentry: file
2223  * @attr: new attributes
2224  *
2225  * Check permission before setting file attributes.  Note that the kernel call
2226  * to notify_change is performed from several locations, whenever file
2227  * attributes change (such as when a file is truncated, chown/chmod operations,
2228  * transferring disk quotas, etc).
2229  *
2230  * Return: Returns 0 if permission is granted.
2231  */
2232 int security_inode_setattr(struct mnt_idmap *idmap,
2233 			   struct dentry *dentry, struct iattr *attr)
2234 {
2235 	if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
2236 		return 0;
2237 	return call_int_hook(inode_setattr, idmap, dentry, attr);
2238 }
2239 EXPORT_SYMBOL_GPL(security_inode_setattr);
2240 
2241 /**
2242  * security_inode_post_setattr() - Update the inode after a setattr operation
2243  * @idmap: idmap of the mount
2244  * @dentry: file
2245  * @ia_valid: file attributes set
2246  *
2247  * Update inode security field after successful setting file attributes.
2248  */
2249 void security_inode_post_setattr(struct mnt_idmap *idmap, struct dentry *dentry,
2250 				 int ia_valid)
2251 {
2252 	if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
2253 		return;
2254 	call_void_hook(inode_post_setattr, idmap, dentry, ia_valid);
2255 }
2256 
2257 /**
2258  * security_inode_getattr() - Check if getting file attributes is allowed
2259  * @path: file
2260  *
2261  * Check permission before obtaining file attributes.
2262  *
2263  * Return: Returns 0 if permission is granted.
2264  */
2265 int security_inode_getattr(const struct path *path)
2266 {
2267 	if (unlikely(IS_PRIVATE(d_backing_inode(path->dentry))))
2268 		return 0;
2269 	return call_int_hook(inode_getattr, path);
2270 }
2271 
2272 /**
2273  * security_inode_setxattr() - Check if setting file xattrs is allowed
2274  * @idmap: idmap of the mount
2275  * @dentry: file
2276  * @name: xattr name
2277  * @value: xattr value
2278  * @size: size of xattr value
2279  * @flags: flags
2280  *
2281  * This hook performs the desired permission checks before setting the extended
2282  * attributes (xattrs) on @dentry.  It is important to note that we have some
2283  * additional logic before the main LSM implementation calls to detect if we
2284  * need to perform an additional capability check at the LSM layer.
2285  *
2286  * Normally we enforce a capability check prior to executing the various LSM
2287  * hook implementations, but if a LSM wants to avoid this capability check,
2288  * it can register a 'inode_xattr_skipcap' hook and return a value of 1 for
2289  * xattrs that it wants to avoid the capability check, leaving the LSM fully
2290  * responsible for enforcing the access control for the specific xattr.  If all
2291  * of the enabled LSMs refrain from registering a 'inode_xattr_skipcap' hook,
2292  * or return a 0 (the default return value), the capability check is still
2293  * performed.  If no 'inode_xattr_skipcap' hooks are registered the capability
2294  * check is performed.
2295  *
2296  * Return: Returns 0 if permission is granted.
2297  */
2298 int security_inode_setxattr(struct mnt_idmap *idmap,
2299 			    struct dentry *dentry, const char *name,
2300 			    const void *value, size_t size, int flags)
2301 {
2302 	int rc;
2303 
2304 	if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
2305 		return 0;
2306 
2307 	/* enforce the capability checks at the lsm layer, if needed */
2308 	if (!call_int_hook(inode_xattr_skipcap, name)) {
2309 		rc = cap_inode_setxattr(dentry, name, value, size, flags);
2310 		if (rc)
2311 			return rc;
2312 	}
2313 
2314 	return call_int_hook(inode_setxattr, idmap, dentry, name, value, size,
2315 			     flags);
2316 }
2317 
2318 /**
2319  * security_inode_set_acl() - Check if setting posix acls is allowed
2320  * @idmap: idmap of the mount
2321  * @dentry: file
2322  * @acl_name: acl name
2323  * @kacl: acl struct
2324  *
2325  * Check permission before setting posix acls, the posix acls in @kacl are
2326  * identified by @acl_name.
2327  *
2328  * Return: Returns 0 if permission is granted.
2329  */
2330 int security_inode_set_acl(struct mnt_idmap *idmap,
2331 			   struct dentry *dentry, const char *acl_name,
2332 			   struct posix_acl *kacl)
2333 {
2334 	if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
2335 		return 0;
2336 	return call_int_hook(inode_set_acl, idmap, dentry, acl_name, kacl);
2337 }
2338 
2339 /**
2340  * security_inode_post_set_acl() - Update inode security from posix acls set
2341  * @dentry: file
2342  * @acl_name: acl name
2343  * @kacl: acl struct
2344  *
2345  * Update inode security data after successfully setting posix acls on @dentry.
2346  * The posix acls in @kacl are identified by @acl_name.
2347  */
2348 void security_inode_post_set_acl(struct dentry *dentry, const char *acl_name,
2349 				 struct posix_acl *kacl)
2350 {
2351 	if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
2352 		return;
2353 	call_void_hook(inode_post_set_acl, dentry, acl_name, kacl);
2354 }
2355 
2356 /**
2357  * security_inode_get_acl() - Check if reading posix acls is allowed
2358  * @idmap: idmap of the mount
2359  * @dentry: file
2360  * @acl_name: acl name
2361  *
2362  * Check permission before getting osix acls, the posix acls are identified by
2363  * @acl_name.
2364  *
2365  * Return: Returns 0 if permission is granted.
2366  */
2367 int security_inode_get_acl(struct mnt_idmap *idmap,
2368 			   struct dentry *dentry, const char *acl_name)
2369 {
2370 	if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
2371 		return 0;
2372 	return call_int_hook(inode_get_acl, idmap, dentry, acl_name);
2373 }
2374 
2375 /**
2376  * security_inode_remove_acl() - Check if removing a posix acl is allowed
2377  * @idmap: idmap of the mount
2378  * @dentry: file
2379  * @acl_name: acl name
2380  *
2381  * Check permission before removing posix acls, the posix acls are identified
2382  * by @acl_name.
2383  *
2384  * Return: Returns 0 if permission is granted.
2385  */
2386 int security_inode_remove_acl(struct mnt_idmap *idmap,
2387 			      struct dentry *dentry, const char *acl_name)
2388 {
2389 	if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
2390 		return 0;
2391 	return call_int_hook(inode_remove_acl, idmap, dentry, acl_name);
2392 }
2393 
2394 /**
2395  * security_inode_post_remove_acl() - Update inode security after rm posix acls
2396  * @idmap: idmap of the mount
2397  * @dentry: file
2398  * @acl_name: acl name
2399  *
2400  * Update inode security data after successfully removing posix acls on
2401  * @dentry in @idmap. The posix acls are identified by @acl_name.
2402  */
2403 void security_inode_post_remove_acl(struct mnt_idmap *idmap,
2404 				    struct dentry *dentry, const char *acl_name)
2405 {
2406 	if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
2407 		return;
2408 	call_void_hook(inode_post_remove_acl, idmap, dentry, acl_name);
2409 }
2410 
2411 /**
2412  * security_inode_post_setxattr() - Update the inode after a setxattr operation
2413  * @dentry: file
2414  * @name: xattr name
2415  * @value: xattr value
2416  * @size: xattr value size
2417  * @flags: flags
2418  *
2419  * Update inode security field after successful setxattr operation.
2420  */
2421 void security_inode_post_setxattr(struct dentry *dentry, const char *name,
2422 				  const void *value, size_t size, int flags)
2423 {
2424 	if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
2425 		return;
2426 	call_void_hook(inode_post_setxattr, dentry, name, value, size, flags);
2427 }
2428 
2429 /**
2430  * security_inode_getxattr() - Check if xattr access is allowed
2431  * @dentry: file
2432  * @name: xattr name
2433  *
2434  * Check permission before obtaining the extended attributes identified by
2435  * @name for @dentry.
2436  *
2437  * Return: Returns 0 if permission is granted.
2438  */
2439 int security_inode_getxattr(struct dentry *dentry, const char *name)
2440 {
2441 	if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
2442 		return 0;
2443 	return call_int_hook(inode_getxattr, dentry, name);
2444 }
2445 
2446 /**
2447  * security_inode_listxattr() - Check if listing xattrs is allowed
2448  * @dentry: file
2449  *
2450  * Check permission before obtaining the list of extended attribute names for
2451  * @dentry.
2452  *
2453  * Return: Returns 0 if permission is granted.
2454  */
2455 int security_inode_listxattr(struct dentry *dentry)
2456 {
2457 	if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
2458 		return 0;
2459 	return call_int_hook(inode_listxattr, dentry);
2460 }
2461 
2462 /**
2463  * security_inode_removexattr() - Check if removing an xattr is allowed
2464  * @idmap: idmap of the mount
2465  * @dentry: file
2466  * @name: xattr name
2467  *
2468  * This hook performs the desired permission checks before setting the extended
2469  * attributes (xattrs) on @dentry.  It is important to note that we have some
2470  * additional logic before the main LSM implementation calls to detect if we
2471  * need to perform an additional capability check at the LSM layer.
2472  *
2473  * Normally we enforce a capability check prior to executing the various LSM
2474  * hook implementations, but if a LSM wants to avoid this capability check,
2475  * it can register a 'inode_xattr_skipcap' hook and return a value of 1 for
2476  * xattrs that it wants to avoid the capability check, leaving the LSM fully
2477  * responsible for enforcing the access control for the specific xattr.  If all
2478  * of the enabled LSMs refrain from registering a 'inode_xattr_skipcap' hook,
2479  * or return a 0 (the default return value), the capability check is still
2480  * performed.  If no 'inode_xattr_skipcap' hooks are registered the capability
2481  * check is performed.
2482  *
2483  * Return: Returns 0 if permission is granted.
2484  */
2485 int security_inode_removexattr(struct mnt_idmap *idmap,
2486 			       struct dentry *dentry, const char *name)
2487 {
2488 	int rc;
2489 
2490 	if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
2491 		return 0;
2492 
2493 	/* enforce the capability checks at the lsm layer, if needed */
2494 	if (!call_int_hook(inode_xattr_skipcap, name)) {
2495 		rc = cap_inode_removexattr(idmap, dentry, name);
2496 		if (rc)
2497 			return rc;
2498 	}
2499 
2500 	return call_int_hook(inode_removexattr, idmap, dentry, name);
2501 }
2502 
2503 /**
2504  * security_inode_post_removexattr() - Update the inode after a removexattr op
2505  * @dentry: file
2506  * @name: xattr name
2507  *
2508  * Update the inode after a successful removexattr operation.
2509  */
2510 void security_inode_post_removexattr(struct dentry *dentry, const char *name)
2511 {
2512 	if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
2513 		return;
2514 	call_void_hook(inode_post_removexattr, dentry, name);
2515 }
2516 
2517 /**
2518  * security_inode_need_killpriv() - Check if security_inode_killpriv() required
2519  * @dentry: associated dentry
2520  *
2521  * Called when an inode has been changed to determine if
2522  * security_inode_killpriv() should be called.
2523  *
2524  * Return: Return <0 on error to abort the inode change operation, return 0 if
2525  *         security_inode_killpriv() does not need to be called, return >0 if
2526  *         security_inode_killpriv() does need to be called.
2527  */
2528 int security_inode_need_killpriv(struct dentry *dentry)
2529 {
2530 	return call_int_hook(inode_need_killpriv, dentry);
2531 }
2532 
2533 /**
2534  * security_inode_killpriv() - The setuid bit is removed, update LSM state
2535  * @idmap: idmap of the mount
2536  * @dentry: associated dentry
2537  *
2538  * The @dentry's setuid bit is being removed.  Remove similar security labels.
2539  * Called with the dentry->d_inode->i_mutex held.
2540  *
2541  * Return: Return 0 on success.  If error is returned, then the operation
2542  *         causing setuid bit removal is failed.
2543  */
2544 int security_inode_killpriv(struct mnt_idmap *idmap,
2545 			    struct dentry *dentry)
2546 {
2547 	return call_int_hook(inode_killpriv, idmap, dentry);
2548 }
2549 
2550 /**
2551  * security_inode_getsecurity() - Get the xattr security label of an inode
2552  * @idmap: idmap of the mount
2553  * @inode: inode
2554  * @name: xattr name
2555  * @buffer: security label buffer
2556  * @alloc: allocation flag
2557  *
2558  * Retrieve a copy of the extended attribute representation of the security
2559  * label associated with @name for @inode via @buffer.  Note that @name is the
2560  * remainder of the attribute name after the security prefix has been removed.
2561  * @alloc is used to specify if the call should return a value via the buffer
2562  * or just the value length.
2563  *
2564  * Return: Returns size of buffer on success.
2565  */
2566 int security_inode_getsecurity(struct mnt_idmap *idmap,
2567 			       struct inode *inode, const char *name,
2568 			       void **buffer, bool alloc)
2569 {
2570 	if (unlikely(IS_PRIVATE(inode)))
2571 		return LSM_RET_DEFAULT(inode_getsecurity);
2572 
2573 	return call_int_hook(inode_getsecurity, idmap, inode, name, buffer,
2574 			     alloc);
2575 }
2576 
2577 /**
2578  * security_inode_setsecurity() - Set the xattr security label of an inode
2579  * @inode: inode
2580  * @name: xattr name
2581  * @value: security label
2582  * @size: length of security label
2583  * @flags: flags
2584  *
2585  * Set the security label associated with @name for @inode from the extended
2586  * attribute value @value.  @size indicates the size of the @value in bytes.
2587  * @flags may be XATTR_CREATE, XATTR_REPLACE, or 0. Note that @name is the
2588  * remainder of the attribute name after the security. prefix has been removed.
2589  *
2590  * Return: Returns 0 on success.
2591  */
2592 int security_inode_setsecurity(struct inode *inode, const char *name,
2593 			       const void *value, size_t size, int flags)
2594 {
2595 	if (unlikely(IS_PRIVATE(inode)))
2596 		return LSM_RET_DEFAULT(inode_setsecurity);
2597 
2598 	return call_int_hook(inode_setsecurity, inode, name, value, size,
2599 			     flags);
2600 }
2601 
2602 /**
2603  * security_inode_listsecurity() - List the xattr security label names
2604  * @inode: inode
2605  * @buffer: buffer
2606  * @buffer_size: size of buffer
2607  *
2608  * Copy the extended attribute names for the security labels associated with
2609  * @inode into @buffer.  The maximum size of @buffer is specified by
2610  * @buffer_size.  @buffer may be NULL to request the size of the buffer
2611  * required.
2612  *
2613  * Return: Returns number of bytes used/required on success.
2614  */
2615 int security_inode_listsecurity(struct inode *inode,
2616 				char *buffer, size_t buffer_size)
2617 {
2618 	if (unlikely(IS_PRIVATE(inode)))
2619 		return 0;
2620 	return call_int_hook(inode_listsecurity, inode, buffer, buffer_size);
2621 }
2622 EXPORT_SYMBOL(security_inode_listsecurity);
2623 
2624 /**
2625  * security_inode_getsecid() - Get an inode's secid
2626  * @inode: inode
2627  * @secid: secid to return
2628  *
2629  * Get the secid associated with the node.  In case of failure, @secid will be
2630  * set to zero.
2631  */
2632 void security_inode_getsecid(struct inode *inode, u32 *secid)
2633 {
2634 	call_void_hook(inode_getsecid, inode, secid);
2635 }
2636 
2637 /**
2638  * security_inode_copy_up() - Create new creds for an overlayfs copy-up op
2639  * @src: union dentry of copy-up file
2640  * @new: newly created creds
2641  *
2642  * A file is about to be copied up from lower layer to upper layer of overlay
2643  * filesystem. Security module can prepare a set of new creds and modify as
2644  * need be and return new creds. Caller will switch to new creds temporarily to
2645  * create new file and release newly allocated creds.
2646  *
2647  * Return: Returns 0 on success or a negative error code on error.
2648  */
2649 int security_inode_copy_up(struct dentry *src, struct cred **new)
2650 {
2651 	return call_int_hook(inode_copy_up, src, new);
2652 }
2653 EXPORT_SYMBOL(security_inode_copy_up);
2654 
2655 /**
2656  * security_inode_copy_up_xattr() - Filter xattrs in an overlayfs copy-up op
2657  * @src: union dentry of copy-up file
2658  * @name: xattr name
2659  *
2660  * Filter the xattrs being copied up when a unioned file is copied up from a
2661  * lower layer to the union/overlay layer.   The caller is responsible for
2662  * reading and writing the xattrs, this hook is merely a filter.
2663  *
2664  * Return: Returns 0 to accept the xattr, 1 to discard the xattr, -EOPNOTSUPP
2665  *         if the security module does not know about attribute, or a negative
2666  *         error code to abort the copy up.
2667  */
2668 int security_inode_copy_up_xattr(struct dentry *src, const char *name)
2669 {
2670 	int rc;
2671 
2672 	/*
2673 	 * The implementation can return 0 (accept the xattr), 1 (discard the
2674 	 * xattr), -EOPNOTSUPP if it does not know anything about the xattr or
2675 	 * any other error code in case of an error.
2676 	 */
2677 	rc = call_int_hook(inode_copy_up_xattr, src, name);
2678 	if (rc != LSM_RET_DEFAULT(inode_copy_up_xattr))
2679 		return rc;
2680 
2681 	return LSM_RET_DEFAULT(inode_copy_up_xattr);
2682 }
2683 EXPORT_SYMBOL(security_inode_copy_up_xattr);
2684 
2685 /**
2686  * security_kernfs_init_security() - Init LSM context for a kernfs node
2687  * @kn_dir: parent kernfs node
2688  * @kn: the kernfs node to initialize
2689  *
2690  * Initialize the security context of a newly created kernfs node based on its
2691  * own and its parent's attributes.
2692  *
2693  * Return: Returns 0 if permission is granted.
2694  */
2695 int security_kernfs_init_security(struct kernfs_node *kn_dir,
2696 				  struct kernfs_node *kn)
2697 {
2698 	return call_int_hook(kernfs_init_security, kn_dir, kn);
2699 }
2700 
2701 /**
2702  * security_file_permission() - Check file permissions
2703  * @file: file
2704  * @mask: requested permissions
2705  *
2706  * Check file permissions before accessing an open file.  This hook is called
2707  * by various operations that read or write files.  A security module can use
2708  * this hook to perform additional checking on these operations, e.g. to
2709  * revalidate permissions on use to support privilege bracketing or policy
2710  * changes.  Notice that this hook is used when the actual read/write
2711  * operations are performed, whereas the inode_security_ops hook is called when
2712  * a file is opened (as well as many other operations).  Although this hook can
2713  * be used to revalidate permissions for various system call operations that
2714  * read or write files, it does not address the revalidation of permissions for
2715  * memory-mapped files.  Security modules must handle this separately if they
2716  * need such revalidation.
2717  *
2718  * Return: Returns 0 if permission is granted.
2719  */
2720 int security_file_permission(struct file *file, int mask)
2721 {
2722 	return call_int_hook(file_permission, file, mask);
2723 }
2724 
2725 /**
2726  * security_file_alloc() - Allocate and init a file's LSM blob
2727  * @file: the file
2728  *
2729  * Allocate and attach a security structure to the file->f_security field.  The
2730  * security field is initialized to NULL when the structure is first created.
2731  *
2732  * Return: Return 0 if the hook is successful and permission is granted.
2733  */
2734 int security_file_alloc(struct file *file)
2735 {
2736 	int rc = lsm_file_alloc(file);
2737 
2738 	if (rc)
2739 		return rc;
2740 	rc = call_int_hook(file_alloc_security, file);
2741 	if (unlikely(rc))
2742 		security_file_free(file);
2743 	return rc;
2744 }
2745 
2746 /**
2747  * security_file_release() - Perform actions before releasing the file ref
2748  * @file: the file
2749  *
2750  * Perform actions before releasing the last reference to a file.
2751  */
2752 void security_file_release(struct file *file)
2753 {
2754 	call_void_hook(file_release, file);
2755 }
2756 
2757 /**
2758  * security_file_free() - Free a file's LSM blob
2759  * @file: the file
2760  *
2761  * Deallocate and free any security structures stored in file->f_security.
2762  */
2763 void security_file_free(struct file *file)
2764 {
2765 	void *blob;
2766 
2767 	call_void_hook(file_free_security, file);
2768 
2769 	blob = file->f_security;
2770 	if (blob) {
2771 		file->f_security = NULL;
2772 		kmem_cache_free(lsm_file_cache, blob);
2773 	}
2774 }
2775 
2776 /**
2777  * security_file_ioctl() - Check if an ioctl is allowed
2778  * @file: associated file
2779  * @cmd: ioctl cmd
2780  * @arg: ioctl arguments
2781  *
2782  * Check permission for an ioctl operation on @file.  Note that @arg sometimes
2783  * represents a user space pointer; in other cases, it may be a simple integer
2784  * value.  When @arg represents a user space pointer, it should never be used
2785  * by the security module.
2786  *
2787  * Return: Returns 0 if permission is granted.
2788  */
2789 int security_file_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
2790 {
2791 	return call_int_hook(file_ioctl, file, cmd, arg);
2792 }
2793 EXPORT_SYMBOL_GPL(security_file_ioctl);
2794 
2795 /**
2796  * security_file_ioctl_compat() - Check if an ioctl is allowed in compat mode
2797  * @file: associated file
2798  * @cmd: ioctl cmd
2799  * @arg: ioctl arguments
2800  *
2801  * Compat version of security_file_ioctl() that correctly handles 32-bit
2802  * processes running on 64-bit kernels.
2803  *
2804  * Return: Returns 0 if permission is granted.
2805  */
2806 int security_file_ioctl_compat(struct file *file, unsigned int cmd,
2807 			       unsigned long arg)
2808 {
2809 	return call_int_hook(file_ioctl_compat, file, cmd, arg);
2810 }
2811 EXPORT_SYMBOL_GPL(security_file_ioctl_compat);
2812 
2813 static inline unsigned long mmap_prot(struct file *file, unsigned long prot)
2814 {
2815 	/*
2816 	 * Does we have PROT_READ and does the application expect
2817 	 * it to imply PROT_EXEC?  If not, nothing to talk about...
2818 	 */
2819 	if ((prot & (PROT_READ | PROT_EXEC)) != PROT_READ)
2820 		return prot;
2821 	if (!(current->personality & READ_IMPLIES_EXEC))
2822 		return prot;
2823 	/*
2824 	 * if that's an anonymous mapping, let it.
2825 	 */
2826 	if (!file)
2827 		return prot | PROT_EXEC;
2828 	/*
2829 	 * ditto if it's not on noexec mount, except that on !MMU we need
2830 	 * NOMMU_MAP_EXEC (== VM_MAYEXEC) in this case
2831 	 */
2832 	if (!path_noexec(&file->f_path)) {
2833 #ifndef CONFIG_MMU
2834 		if (file->f_op->mmap_capabilities) {
2835 			unsigned caps = file->f_op->mmap_capabilities(file);
2836 			if (!(caps & NOMMU_MAP_EXEC))
2837 				return prot;
2838 		}
2839 #endif
2840 		return prot | PROT_EXEC;
2841 	}
2842 	/* anything on noexec mount won't get PROT_EXEC */
2843 	return prot;
2844 }
2845 
2846 /**
2847  * security_mmap_file() - Check if mmap'ing a file is allowed
2848  * @file: file
2849  * @prot: protection applied by the kernel
2850  * @flags: flags
2851  *
2852  * Check permissions for a mmap operation.  The @file may be NULL, e.g. if
2853  * mapping anonymous memory.
2854  *
2855  * Return: Returns 0 if permission is granted.
2856  */
2857 int security_mmap_file(struct file *file, unsigned long prot,
2858 		       unsigned long flags)
2859 {
2860 	return call_int_hook(mmap_file, file, prot, mmap_prot(file, prot),
2861 			     flags);
2862 }
2863 
2864 /**
2865  * security_mmap_addr() - Check if mmap'ing an address is allowed
2866  * @addr: address
2867  *
2868  * Check permissions for a mmap operation at @addr.
2869  *
2870  * Return: Returns 0 if permission is granted.
2871  */
2872 int security_mmap_addr(unsigned long addr)
2873 {
2874 	return call_int_hook(mmap_addr, addr);
2875 }
2876 
2877 /**
2878  * security_file_mprotect() - Check if changing memory protections is allowed
2879  * @vma: memory region
2880  * @reqprot: application requested protection
2881  * @prot: protection applied by the kernel
2882  *
2883  * Check permissions before changing memory access permissions.
2884  *
2885  * Return: Returns 0 if permission is granted.
2886  */
2887 int security_file_mprotect(struct vm_area_struct *vma, unsigned long reqprot,
2888 			   unsigned long prot)
2889 {
2890 	return call_int_hook(file_mprotect, vma, reqprot, prot);
2891 }
2892 
2893 /**
2894  * security_file_lock() - Check if a file lock is allowed
2895  * @file: file
2896  * @cmd: lock operation (e.g. F_RDLCK, F_WRLCK)
2897  *
2898  * Check permission before performing file locking operations.  Note the hook
2899  * mediates both flock and fcntl style locks.
2900  *
2901  * Return: Returns 0 if permission is granted.
2902  */
2903 int security_file_lock(struct file *file, unsigned int cmd)
2904 {
2905 	return call_int_hook(file_lock, file, cmd);
2906 }
2907 
2908 /**
2909  * security_file_fcntl() - Check if fcntl() op is allowed
2910  * @file: file
2911  * @cmd: fcntl command
2912  * @arg: command argument
2913  *
2914  * Check permission before allowing the file operation specified by @cmd from
2915  * being performed on the file @file.  Note that @arg sometimes represents a
2916  * user space pointer; in other cases, it may be a simple integer value.  When
2917  * @arg represents a user space pointer, it should never be used by the
2918  * security module.
2919  *
2920  * Return: Returns 0 if permission is granted.
2921  */
2922 int security_file_fcntl(struct file *file, unsigned int cmd, unsigned long arg)
2923 {
2924 	return call_int_hook(file_fcntl, file, cmd, arg);
2925 }
2926 
2927 /**
2928  * security_file_set_fowner() - Set the file owner info in the LSM blob
2929  * @file: the file
2930  *
2931  * Save owner security information (typically from current->security) in
2932  * file->f_security for later use by the send_sigiotask hook.
2933  *
2934  * Return: Returns 0 on success.
2935  */
2936 void security_file_set_fowner(struct file *file)
2937 {
2938 	call_void_hook(file_set_fowner, file);
2939 }
2940 
2941 /**
2942  * security_file_send_sigiotask() - Check if sending SIGIO/SIGURG is allowed
2943  * @tsk: target task
2944  * @fown: signal sender
2945  * @sig: signal to be sent, SIGIO is sent if 0
2946  *
2947  * Check permission for the file owner @fown to send SIGIO or SIGURG to the
2948  * process @tsk.  Note that this hook is sometimes called from interrupt.  Note
2949  * that the fown_struct, @fown, is never outside the context of a struct file,
2950  * so the file structure (and associated security information) can always be
2951  * obtained: container_of(fown, struct file, f_owner).
2952  *
2953  * Return: Returns 0 if permission is granted.
2954  */
2955 int security_file_send_sigiotask(struct task_struct *tsk,
2956 				 struct fown_struct *fown, int sig)
2957 {
2958 	return call_int_hook(file_send_sigiotask, tsk, fown, sig);
2959 }
2960 
2961 /**
2962  * security_file_receive() - Check if receiving a file via IPC is allowed
2963  * @file: file being received
2964  *
2965  * This hook allows security modules to control the ability of a process to
2966  * receive an open file descriptor via socket IPC.
2967  *
2968  * Return: Returns 0 if permission is granted.
2969  */
2970 int security_file_receive(struct file *file)
2971 {
2972 	return call_int_hook(file_receive, file);
2973 }
2974 
2975 /**
2976  * security_file_open() - Save open() time state for late use by the LSM
2977  * @file:
2978  *
2979  * Save open-time permission checking state for later use upon file_permission,
2980  * and recheck access if anything has changed since inode_permission.
2981  *
2982  * Return: Returns 0 if permission is granted.
2983  */
2984 int security_file_open(struct file *file)
2985 {
2986 	int ret;
2987 
2988 	ret = call_int_hook(file_open, file);
2989 	if (ret)
2990 		return ret;
2991 
2992 	return fsnotify_open_perm(file);
2993 }
2994 
2995 /**
2996  * security_file_post_open() - Evaluate a file after it has been opened
2997  * @file: the file
2998  * @mask: access mask
2999  *
3000  * Evaluate an opened file and the access mask requested with open(). The hook
3001  * is useful for LSMs that require the file content to be available in order to
3002  * make decisions.
3003  *
3004  * Return: Returns 0 if permission is granted.
3005  */
3006 int security_file_post_open(struct file *file, int mask)
3007 {
3008 	return call_int_hook(file_post_open, file, mask);
3009 }
3010 EXPORT_SYMBOL_GPL(security_file_post_open);
3011 
3012 /**
3013  * security_file_truncate() - Check if truncating a file is allowed
3014  * @file: file
3015  *
3016  * Check permission before truncating a file, i.e. using ftruncate.  Note that
3017  * truncation permission may also be checked based on the path, using the
3018  * @path_truncate hook.
3019  *
3020  * Return: Returns 0 if permission is granted.
3021  */
3022 int security_file_truncate(struct file *file)
3023 {
3024 	return call_int_hook(file_truncate, file);
3025 }
3026 
3027 /**
3028  * security_task_alloc() - Allocate a task's LSM blob
3029  * @task: the task
3030  * @clone_flags: flags indicating what is being shared
3031  *
3032  * Handle allocation of task-related resources.
3033  *
3034  * Return: Returns a zero on success, negative values on failure.
3035  */
3036 int security_task_alloc(struct task_struct *task, unsigned long clone_flags)
3037 {
3038 	int rc = lsm_task_alloc(task);
3039 
3040 	if (rc)
3041 		return rc;
3042 	rc = call_int_hook(task_alloc, task, clone_flags);
3043 	if (unlikely(rc))
3044 		security_task_free(task);
3045 	return rc;
3046 }
3047 
3048 /**
3049  * security_task_free() - Free a task's LSM blob and related resources
3050  * @task: task
3051  *
3052  * Handle release of task-related resources.  Note that this can be called from
3053  * interrupt context.
3054  */
3055 void security_task_free(struct task_struct *task)
3056 {
3057 	call_void_hook(task_free, task);
3058 
3059 	kfree(task->security);
3060 	task->security = NULL;
3061 }
3062 
3063 /**
3064  * security_cred_alloc_blank() - Allocate the min memory to allow cred_transfer
3065  * @cred: credentials
3066  * @gfp: gfp flags
3067  *
3068  * Only allocate sufficient memory and attach to @cred such that
3069  * cred_transfer() will not get ENOMEM.
3070  *
3071  * Return: Returns 0 on success, negative values on failure.
3072  */
3073 int security_cred_alloc_blank(struct cred *cred, gfp_t gfp)
3074 {
3075 	int rc = lsm_cred_alloc(cred, gfp);
3076 
3077 	if (rc)
3078 		return rc;
3079 
3080 	rc = call_int_hook(cred_alloc_blank, cred, gfp);
3081 	if (unlikely(rc))
3082 		security_cred_free(cred);
3083 	return rc;
3084 }
3085 
3086 /**
3087  * security_cred_free() - Free the cred's LSM blob and associated resources
3088  * @cred: credentials
3089  *
3090  * Deallocate and clear the cred->security field in a set of credentials.
3091  */
3092 void security_cred_free(struct cred *cred)
3093 {
3094 	/*
3095 	 * There is a failure case in prepare_creds() that
3096 	 * may result in a call here with ->security being NULL.
3097 	 */
3098 	if (unlikely(cred->security == NULL))
3099 		return;
3100 
3101 	call_void_hook(cred_free, cred);
3102 
3103 	kfree(cred->security);
3104 	cred->security = NULL;
3105 }
3106 
3107 /**
3108  * security_prepare_creds() - Prepare a new set of credentials
3109  * @new: new credentials
3110  * @old: original credentials
3111  * @gfp: gfp flags
3112  *
3113  * Prepare a new set of credentials by copying the data from the old set.
3114  *
3115  * Return: Returns 0 on success, negative values on failure.
3116  */
3117 int security_prepare_creds(struct cred *new, const struct cred *old, gfp_t gfp)
3118 {
3119 	int rc = lsm_cred_alloc(new, gfp);
3120 
3121 	if (rc)
3122 		return rc;
3123 
3124 	rc = call_int_hook(cred_prepare, new, old, gfp);
3125 	if (unlikely(rc))
3126 		security_cred_free(new);
3127 	return rc;
3128 }
3129 
3130 /**
3131  * security_transfer_creds() - Transfer creds
3132  * @new: target credentials
3133  * @old: original credentials
3134  *
3135  * Transfer data from original creds to new creds.
3136  */
3137 void security_transfer_creds(struct cred *new, const struct cred *old)
3138 {
3139 	call_void_hook(cred_transfer, new, old);
3140 }
3141 
3142 /**
3143  * security_cred_getsecid() - Get the secid from a set of credentials
3144  * @c: credentials
3145  * @secid: secid value
3146  *
3147  * Retrieve the security identifier of the cred structure @c.  In case of
3148  * failure, @secid will be set to zero.
3149  */
3150 void security_cred_getsecid(const struct cred *c, u32 *secid)
3151 {
3152 	*secid = 0;
3153 	call_void_hook(cred_getsecid, c, secid);
3154 }
3155 EXPORT_SYMBOL(security_cred_getsecid);
3156 
3157 /**
3158  * security_kernel_act_as() - Set the kernel credentials to act as secid
3159  * @new: credentials
3160  * @secid: secid
3161  *
3162  * Set the credentials for a kernel service to act as (subjective context).
3163  * The current task must be the one that nominated @secid.
3164  *
3165  * Return: Returns 0 if successful.
3166  */
3167 int security_kernel_act_as(struct cred *new, u32 secid)
3168 {
3169 	return call_int_hook(kernel_act_as, new, secid);
3170 }
3171 
3172 /**
3173  * security_kernel_create_files_as() - Set file creation context using an inode
3174  * @new: target credentials
3175  * @inode: reference inode
3176  *
3177  * Set the file creation context in a set of credentials to be the same as the
3178  * objective context of the specified inode.  The current task must be the one
3179  * that nominated @inode.
3180  *
3181  * Return: Returns 0 if successful.
3182  */
3183 int security_kernel_create_files_as(struct cred *new, struct inode *inode)
3184 {
3185 	return call_int_hook(kernel_create_files_as, new, inode);
3186 }
3187 
3188 /**
3189  * security_kernel_module_request() - Check if loading a module is allowed
3190  * @kmod_name: module name
3191  *
3192  * Ability to trigger the kernel to automatically upcall to userspace for
3193  * userspace to load a kernel module with the given name.
3194  *
3195  * Return: Returns 0 if successful.
3196  */
3197 int security_kernel_module_request(char *kmod_name)
3198 {
3199 	return call_int_hook(kernel_module_request, kmod_name);
3200 }
3201 
3202 /**
3203  * security_kernel_read_file() - Read a file specified by userspace
3204  * @file: file
3205  * @id: file identifier
3206  * @contents: trust if security_kernel_post_read_file() will be called
3207  *
3208  * Read a file specified by userspace.
3209  *
3210  * Return: Returns 0 if permission is granted.
3211  */
3212 int security_kernel_read_file(struct file *file, enum kernel_read_file_id id,
3213 			      bool contents)
3214 {
3215 	return call_int_hook(kernel_read_file, file, id, contents);
3216 }
3217 EXPORT_SYMBOL_GPL(security_kernel_read_file);
3218 
3219 /**
3220  * security_kernel_post_read_file() - Read a file specified by userspace
3221  * @file: file
3222  * @buf: file contents
3223  * @size: size of file contents
3224  * @id: file identifier
3225  *
3226  * Read a file specified by userspace.  This must be paired with a prior call
3227  * to security_kernel_read_file() call that indicated this hook would also be
3228  * called, see security_kernel_read_file() for more information.
3229  *
3230  * Return: Returns 0 if permission is granted.
3231  */
3232 int security_kernel_post_read_file(struct file *file, char *buf, loff_t size,
3233 				   enum kernel_read_file_id id)
3234 {
3235 	return call_int_hook(kernel_post_read_file, file, buf, size, id);
3236 }
3237 EXPORT_SYMBOL_GPL(security_kernel_post_read_file);
3238 
3239 /**
3240  * security_kernel_load_data() - Load data provided by userspace
3241  * @id: data identifier
3242  * @contents: true if security_kernel_post_load_data() will be called
3243  *
3244  * Load data provided by userspace.
3245  *
3246  * Return: Returns 0 if permission is granted.
3247  */
3248 int security_kernel_load_data(enum kernel_load_data_id id, bool contents)
3249 {
3250 	return call_int_hook(kernel_load_data, id, contents);
3251 }
3252 EXPORT_SYMBOL_GPL(security_kernel_load_data);
3253 
3254 /**
3255  * security_kernel_post_load_data() - Load userspace data from a non-file source
3256  * @buf: data
3257  * @size: size of data
3258  * @id: data identifier
3259  * @description: text description of data, specific to the id value
3260  *
3261  * Load data provided by a non-file source (usually userspace buffer).  This
3262  * must be paired with a prior security_kernel_load_data() call that indicated
3263  * this hook would also be called, see security_kernel_load_data() for more
3264  * information.
3265  *
3266  * Return: Returns 0 if permission is granted.
3267  */
3268 int security_kernel_post_load_data(char *buf, loff_t size,
3269 				   enum kernel_load_data_id id,
3270 				   char *description)
3271 {
3272 	return call_int_hook(kernel_post_load_data, buf, size, id, description);
3273 }
3274 EXPORT_SYMBOL_GPL(security_kernel_post_load_data);
3275 
3276 /**
3277  * security_task_fix_setuid() - Update LSM with new user id attributes
3278  * @new: updated credentials
3279  * @old: credentials being replaced
3280  * @flags: LSM_SETID_* flag values
3281  *
3282  * Update the module's state after setting one or more of the user identity
3283  * attributes of the current process.  The @flags parameter indicates which of
3284  * the set*uid system calls invoked this hook.  If @new is the set of
3285  * credentials that will be installed.  Modifications should be made to this
3286  * rather than to @current->cred.
3287  *
3288  * Return: Returns 0 on success.
3289  */
3290 int security_task_fix_setuid(struct cred *new, const struct cred *old,
3291 			     int flags)
3292 {
3293 	return call_int_hook(task_fix_setuid, new, old, flags);
3294 }
3295 
3296 /**
3297  * security_task_fix_setgid() - Update LSM with new group id attributes
3298  * @new: updated credentials
3299  * @old: credentials being replaced
3300  * @flags: LSM_SETID_* flag value
3301  *
3302  * Update the module's state after setting one or more of the group identity
3303  * attributes of the current process.  The @flags parameter indicates which of
3304  * the set*gid system calls invoked this hook.  @new is the set of credentials
3305  * that will be installed.  Modifications should be made to this rather than to
3306  * @current->cred.
3307  *
3308  * Return: Returns 0 on success.
3309  */
3310 int security_task_fix_setgid(struct cred *new, const struct cred *old,
3311 			     int flags)
3312 {
3313 	return call_int_hook(task_fix_setgid, new, old, flags);
3314 }
3315 
3316 /**
3317  * security_task_fix_setgroups() - Update LSM with new supplementary groups
3318  * @new: updated credentials
3319  * @old: credentials being replaced
3320  *
3321  * Update the module's state after setting the supplementary group identity
3322  * attributes of the current process.  @new is the set of credentials that will
3323  * be installed.  Modifications should be made to this rather than to
3324  * @current->cred.
3325  *
3326  * Return: Returns 0 on success.
3327  */
3328 int security_task_fix_setgroups(struct cred *new, const struct cred *old)
3329 {
3330 	return call_int_hook(task_fix_setgroups, new, old);
3331 }
3332 
3333 /**
3334  * security_task_setpgid() - Check if setting the pgid is allowed
3335  * @p: task being modified
3336  * @pgid: new pgid
3337  *
3338  * Check permission before setting the process group identifier of the process
3339  * @p to @pgid.
3340  *
3341  * Return: Returns 0 if permission is granted.
3342  */
3343 int security_task_setpgid(struct task_struct *p, pid_t pgid)
3344 {
3345 	return call_int_hook(task_setpgid, p, pgid);
3346 }
3347 
3348 /**
3349  * security_task_getpgid() - Check if getting the pgid is allowed
3350  * @p: task
3351  *
3352  * Check permission before getting the process group identifier of the process
3353  * @p.
3354  *
3355  * Return: Returns 0 if permission is granted.
3356  */
3357 int security_task_getpgid(struct task_struct *p)
3358 {
3359 	return call_int_hook(task_getpgid, p);
3360 }
3361 
3362 /**
3363  * security_task_getsid() - Check if getting the session id is allowed
3364  * @p: task
3365  *
3366  * Check permission before getting the session identifier of the process @p.
3367  *
3368  * Return: Returns 0 if permission is granted.
3369  */
3370 int security_task_getsid(struct task_struct *p)
3371 {
3372 	return call_int_hook(task_getsid, p);
3373 }
3374 
3375 /**
3376  * security_current_getsecid_subj() - Get the current task's subjective secid
3377  * @secid: secid value
3378  *
3379  * Retrieve the subjective security identifier of the current task and return
3380  * it in @secid.  In case of failure, @secid will be set to zero.
3381  */
3382 void security_current_getsecid_subj(u32 *secid)
3383 {
3384 	*secid = 0;
3385 	call_void_hook(current_getsecid_subj, secid);
3386 }
3387 EXPORT_SYMBOL(security_current_getsecid_subj);
3388 
3389 /**
3390  * security_task_getsecid_obj() - Get a task's objective secid
3391  * @p: target task
3392  * @secid: secid value
3393  *
3394  * Retrieve the objective security identifier of the task_struct in @p and
3395  * return it in @secid. In case of failure, @secid will be set to zero.
3396  */
3397 void security_task_getsecid_obj(struct task_struct *p, u32 *secid)
3398 {
3399 	*secid = 0;
3400 	call_void_hook(task_getsecid_obj, p, secid);
3401 }
3402 EXPORT_SYMBOL(security_task_getsecid_obj);
3403 
3404 /**
3405  * security_task_setnice() - Check if setting a task's nice value is allowed
3406  * @p: target task
3407  * @nice: nice value
3408  *
3409  * Check permission before setting the nice value of @p to @nice.
3410  *
3411  * Return: Returns 0 if permission is granted.
3412  */
3413 int security_task_setnice(struct task_struct *p, int nice)
3414 {
3415 	return call_int_hook(task_setnice, p, nice);
3416 }
3417 
3418 /**
3419  * security_task_setioprio() - Check if setting a task's ioprio is allowed
3420  * @p: target task
3421  * @ioprio: ioprio value
3422  *
3423  * Check permission before setting the ioprio value of @p to @ioprio.
3424  *
3425  * Return: Returns 0 if permission is granted.
3426  */
3427 int security_task_setioprio(struct task_struct *p, int ioprio)
3428 {
3429 	return call_int_hook(task_setioprio, p, ioprio);
3430 }
3431 
3432 /**
3433  * security_task_getioprio() - Check if getting a task's ioprio is allowed
3434  * @p: task
3435  *
3436  * Check permission before getting the ioprio value of @p.
3437  *
3438  * Return: Returns 0 if permission is granted.
3439  */
3440 int security_task_getioprio(struct task_struct *p)
3441 {
3442 	return call_int_hook(task_getioprio, p);
3443 }
3444 
3445 /**
3446  * security_task_prlimit() - Check if get/setting resources limits is allowed
3447  * @cred: current task credentials
3448  * @tcred: target task credentials
3449  * @flags: LSM_PRLIMIT_* flag bits indicating a get/set/both
3450  *
3451  * Check permission before getting and/or setting the resource limits of
3452  * another task.
3453  *
3454  * Return: Returns 0 if permission is granted.
3455  */
3456 int security_task_prlimit(const struct cred *cred, const struct cred *tcred,
3457 			  unsigned int flags)
3458 {
3459 	return call_int_hook(task_prlimit, cred, tcred, flags);
3460 }
3461 
3462 /**
3463  * security_task_setrlimit() - Check if setting a new rlimit value is allowed
3464  * @p: target task's group leader
3465  * @resource: resource whose limit is being set
3466  * @new_rlim: new resource limit
3467  *
3468  * Check permission before setting the resource limits of process @p for
3469  * @resource to @new_rlim.  The old resource limit values can be examined by
3470  * dereferencing (p->signal->rlim + resource).
3471  *
3472  * Return: Returns 0 if permission is granted.
3473  */
3474 int security_task_setrlimit(struct task_struct *p, unsigned int resource,
3475 			    struct rlimit *new_rlim)
3476 {
3477 	return call_int_hook(task_setrlimit, p, resource, new_rlim);
3478 }
3479 
3480 /**
3481  * security_task_setscheduler() - Check if setting sched policy/param is allowed
3482  * @p: target task
3483  *
3484  * Check permission before setting scheduling policy and/or parameters of
3485  * process @p.
3486  *
3487  * Return: Returns 0 if permission is granted.
3488  */
3489 int security_task_setscheduler(struct task_struct *p)
3490 {
3491 	return call_int_hook(task_setscheduler, p);
3492 }
3493 
3494 /**
3495  * security_task_getscheduler() - Check if getting scheduling info is allowed
3496  * @p: target task
3497  *
3498  * Check permission before obtaining scheduling information for process @p.
3499  *
3500  * Return: Returns 0 if permission is granted.
3501  */
3502 int security_task_getscheduler(struct task_struct *p)
3503 {
3504 	return call_int_hook(task_getscheduler, p);
3505 }
3506 
3507 /**
3508  * security_task_movememory() - Check if moving memory is allowed
3509  * @p: task
3510  *
3511  * Check permission before moving memory owned by process @p.
3512  *
3513  * Return: Returns 0 if permission is granted.
3514  */
3515 int security_task_movememory(struct task_struct *p)
3516 {
3517 	return call_int_hook(task_movememory, p);
3518 }
3519 
3520 /**
3521  * security_task_kill() - Check if sending a signal is allowed
3522  * @p: target process
3523  * @info: signal information
3524  * @sig: signal value
3525  * @cred: credentials of the signal sender, NULL if @current
3526  *
3527  * Check permission before sending signal @sig to @p.  @info can be NULL, the
3528  * constant 1, or a pointer to a kernel_siginfo structure.  If @info is 1 or
3529  * SI_FROMKERNEL(info) is true, then the signal should be viewed as coming from
3530  * the kernel and should typically be permitted.  SIGIO signals are handled
3531  * separately by the send_sigiotask hook in file_security_ops.
3532  *
3533  * Return: Returns 0 if permission is granted.
3534  */
3535 int security_task_kill(struct task_struct *p, struct kernel_siginfo *info,
3536 		       int sig, const struct cred *cred)
3537 {
3538 	return call_int_hook(task_kill, p, info, sig, cred);
3539 }
3540 
3541 /**
3542  * security_task_prctl() - Check if a prctl op is allowed
3543  * @option: operation
3544  * @arg2: argument
3545  * @arg3: argument
3546  * @arg4: argument
3547  * @arg5: argument
3548  *
3549  * Check permission before performing a process control operation on the
3550  * current process.
3551  *
3552  * Return: Return -ENOSYS if no-one wanted to handle this op, any other value
3553  *         to cause prctl() to return immediately with that value.
3554  */
3555 int security_task_prctl(int option, unsigned long arg2, unsigned long arg3,
3556 			unsigned long arg4, unsigned long arg5)
3557 {
3558 	int thisrc;
3559 	int rc = LSM_RET_DEFAULT(task_prctl);
3560 	struct security_hook_list *hp;
3561 
3562 	hlist_for_each_entry(hp, &security_hook_heads.task_prctl, list) {
3563 		thisrc = hp->hook.task_prctl(option, arg2, arg3, arg4, arg5);
3564 		if (thisrc != LSM_RET_DEFAULT(task_prctl)) {
3565 			rc = thisrc;
3566 			if (thisrc != 0)
3567 				break;
3568 		}
3569 	}
3570 	return rc;
3571 }
3572 
3573 /**
3574  * security_task_to_inode() - Set the security attributes of a task's inode
3575  * @p: task
3576  * @inode: inode
3577  *
3578  * Set the security attributes for an inode based on an associated task's
3579  * security attributes, e.g. for /proc/pid inodes.
3580  */
3581 void security_task_to_inode(struct task_struct *p, struct inode *inode)
3582 {
3583 	call_void_hook(task_to_inode, p, inode);
3584 }
3585 
3586 /**
3587  * security_create_user_ns() - Check if creating a new userns is allowed
3588  * @cred: prepared creds
3589  *
3590  * Check permission prior to creating a new user namespace.
3591  *
3592  * Return: Returns 0 if successful, otherwise < 0 error code.
3593  */
3594 int security_create_user_ns(const struct cred *cred)
3595 {
3596 	return call_int_hook(userns_create, cred);
3597 }
3598 
3599 /**
3600  * security_ipc_permission() - Check if sysv ipc access is allowed
3601  * @ipcp: ipc permission structure
3602  * @flag: requested permissions
3603  *
3604  * Check permissions for access to IPC.
3605  *
3606  * Return: Returns 0 if permission is granted.
3607  */
3608 int security_ipc_permission(struct kern_ipc_perm *ipcp, short flag)
3609 {
3610 	return call_int_hook(ipc_permission, ipcp, flag);
3611 }
3612 
3613 /**
3614  * security_ipc_getsecid() - Get the sysv ipc object's secid
3615  * @ipcp: ipc permission structure
3616  * @secid: secid pointer
3617  *
3618  * Get the secid associated with the ipc object.  In case of failure, @secid
3619  * will be set to zero.
3620  */
3621 void security_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid)
3622 {
3623 	*secid = 0;
3624 	call_void_hook(ipc_getsecid, ipcp, secid);
3625 }
3626 
3627 /**
3628  * security_msg_msg_alloc() - Allocate a sysv ipc message LSM blob
3629  * @msg: message structure
3630  *
3631  * Allocate and attach a security structure to the msg->security field.  The
3632  * security field is initialized to NULL when the structure is first created.
3633  *
3634  * Return: Return 0 if operation was successful and permission is granted.
3635  */
3636 int security_msg_msg_alloc(struct msg_msg *msg)
3637 {
3638 	int rc = lsm_msg_msg_alloc(msg);
3639 
3640 	if (unlikely(rc))
3641 		return rc;
3642 	rc = call_int_hook(msg_msg_alloc_security, msg);
3643 	if (unlikely(rc))
3644 		security_msg_msg_free(msg);
3645 	return rc;
3646 }
3647 
3648 /**
3649  * security_msg_msg_free() - Free a sysv ipc message LSM blob
3650  * @msg: message structure
3651  *
3652  * Deallocate the security structure for this message.
3653  */
3654 void security_msg_msg_free(struct msg_msg *msg)
3655 {
3656 	call_void_hook(msg_msg_free_security, msg);
3657 	kfree(msg->security);
3658 	msg->security = NULL;
3659 }
3660 
3661 /**
3662  * security_msg_queue_alloc() - Allocate a sysv ipc msg queue LSM blob
3663  * @msq: sysv ipc permission structure
3664  *
3665  * Allocate and attach a security structure to @msg. The security field is
3666  * initialized to NULL when the structure is first created.
3667  *
3668  * Return: Returns 0 if operation was successful and permission is granted.
3669  */
3670 int security_msg_queue_alloc(struct kern_ipc_perm *msq)
3671 {
3672 	int rc = lsm_ipc_alloc(msq);
3673 
3674 	if (unlikely(rc))
3675 		return rc;
3676 	rc = call_int_hook(msg_queue_alloc_security, msq);
3677 	if (unlikely(rc))
3678 		security_msg_queue_free(msq);
3679 	return rc;
3680 }
3681 
3682 /**
3683  * security_msg_queue_free() - Free a sysv ipc msg queue LSM blob
3684  * @msq: sysv ipc permission structure
3685  *
3686  * Deallocate security field @perm->security for the message queue.
3687  */
3688 void security_msg_queue_free(struct kern_ipc_perm *msq)
3689 {
3690 	call_void_hook(msg_queue_free_security, msq);
3691 	kfree(msq->security);
3692 	msq->security = NULL;
3693 }
3694 
3695 /**
3696  * security_msg_queue_associate() - Check if a msg queue operation is allowed
3697  * @msq: sysv ipc permission structure
3698  * @msqflg: operation flags
3699  *
3700  * Check permission when a message queue is requested through the msgget system
3701  * call. This hook is only called when returning the message queue identifier
3702  * for an existing message queue, not when a new message queue is created.
3703  *
3704  * Return: Return 0 if permission is granted.
3705  */
3706 int security_msg_queue_associate(struct kern_ipc_perm *msq, int msqflg)
3707 {
3708 	return call_int_hook(msg_queue_associate, msq, msqflg);
3709 }
3710 
3711 /**
3712  * security_msg_queue_msgctl() - Check if a msg queue operation is allowed
3713  * @msq: sysv ipc permission structure
3714  * @cmd: operation
3715  *
3716  * Check permission when a message control operation specified by @cmd is to be
3717  * performed on the message queue with permissions.
3718  *
3719  * Return: Returns 0 if permission is granted.
3720  */
3721 int security_msg_queue_msgctl(struct kern_ipc_perm *msq, int cmd)
3722 {
3723 	return call_int_hook(msg_queue_msgctl, msq, cmd);
3724 }
3725 
3726 /**
3727  * security_msg_queue_msgsnd() - Check if sending a sysv ipc message is allowed
3728  * @msq: sysv ipc permission structure
3729  * @msg: message
3730  * @msqflg: operation flags
3731  *
3732  * Check permission before a message, @msg, is enqueued on the message queue
3733  * with permissions specified in @msq.
3734  *
3735  * Return: Returns 0 if permission is granted.
3736  */
3737 int security_msg_queue_msgsnd(struct kern_ipc_perm *msq,
3738 			      struct msg_msg *msg, int msqflg)
3739 {
3740 	return call_int_hook(msg_queue_msgsnd, msq, msg, msqflg);
3741 }
3742 
3743 /**
3744  * security_msg_queue_msgrcv() - Check if receiving a sysv ipc msg is allowed
3745  * @msq: sysv ipc permission structure
3746  * @msg: message
3747  * @target: target task
3748  * @type: type of message requested
3749  * @mode: operation flags
3750  *
3751  * Check permission before a message, @msg, is removed from the message	queue.
3752  * The @target task structure contains a pointer to the process that will be
3753  * receiving the message (not equal to the current process when inline receives
3754  * are being performed).
3755  *
3756  * Return: Returns 0 if permission is granted.
3757  */
3758 int security_msg_queue_msgrcv(struct kern_ipc_perm *msq, struct msg_msg *msg,
3759 			      struct task_struct *target, long type, int mode)
3760 {
3761 	return call_int_hook(msg_queue_msgrcv, msq, msg, target, type, mode);
3762 }
3763 
3764 /**
3765  * security_shm_alloc() - Allocate a sysv shm LSM blob
3766  * @shp: sysv ipc permission structure
3767  *
3768  * Allocate and attach a security structure to the @shp security field.  The
3769  * security field is initialized to NULL when the structure is first created.
3770  *
3771  * Return: Returns 0 if operation was successful and permission is granted.
3772  */
3773 int security_shm_alloc(struct kern_ipc_perm *shp)
3774 {
3775 	int rc = lsm_ipc_alloc(shp);
3776 
3777 	if (unlikely(rc))
3778 		return rc;
3779 	rc = call_int_hook(shm_alloc_security, shp);
3780 	if (unlikely(rc))
3781 		security_shm_free(shp);
3782 	return rc;
3783 }
3784 
3785 /**
3786  * security_shm_free() - Free a sysv shm LSM blob
3787  * @shp: sysv ipc permission structure
3788  *
3789  * Deallocate the security structure @perm->security for the memory segment.
3790  */
3791 void security_shm_free(struct kern_ipc_perm *shp)
3792 {
3793 	call_void_hook(shm_free_security, shp);
3794 	kfree(shp->security);
3795 	shp->security = NULL;
3796 }
3797 
3798 /**
3799  * security_shm_associate() - Check if a sysv shm operation is allowed
3800  * @shp: sysv ipc permission structure
3801  * @shmflg: operation flags
3802  *
3803  * Check permission when a shared memory region is requested through the shmget
3804  * system call. This hook is only called when returning the shared memory
3805  * region identifier for an existing region, not when a new shared memory
3806  * region is created.
3807  *
3808  * Return: Returns 0 if permission is granted.
3809  */
3810 int security_shm_associate(struct kern_ipc_perm *shp, int shmflg)
3811 {
3812 	return call_int_hook(shm_associate, shp, shmflg);
3813 }
3814 
3815 /**
3816  * security_shm_shmctl() - Check if a sysv shm operation is allowed
3817  * @shp: sysv ipc permission structure
3818  * @cmd: operation
3819  *
3820  * Check permission when a shared memory control operation specified by @cmd is
3821  * to be performed on the shared memory region with permissions in @shp.
3822  *
3823  * Return: Return 0 if permission is granted.
3824  */
3825 int security_shm_shmctl(struct kern_ipc_perm *shp, int cmd)
3826 {
3827 	return call_int_hook(shm_shmctl, shp, cmd);
3828 }
3829 
3830 /**
3831  * security_shm_shmat() - Check if a sysv shm attach operation is allowed
3832  * @shp: sysv ipc permission structure
3833  * @shmaddr: address of memory region to attach
3834  * @shmflg: operation flags
3835  *
3836  * Check permissions prior to allowing the shmat system call to attach the
3837  * shared memory segment with permissions @shp to the data segment of the
3838  * calling process. The attaching address is specified by @shmaddr.
3839  *
3840  * Return: Returns 0 if permission is granted.
3841  */
3842 int security_shm_shmat(struct kern_ipc_perm *shp,
3843 		       char __user *shmaddr, int shmflg)
3844 {
3845 	return call_int_hook(shm_shmat, shp, shmaddr, shmflg);
3846 }
3847 
3848 /**
3849  * security_sem_alloc() - Allocate a sysv semaphore LSM blob
3850  * @sma: sysv ipc permission structure
3851  *
3852  * Allocate and attach a security structure to the @sma security field. The
3853  * security field is initialized to NULL when the structure is first created.
3854  *
3855  * Return: Returns 0 if operation was successful and permission is granted.
3856  */
3857 int security_sem_alloc(struct kern_ipc_perm *sma)
3858 {
3859 	int rc = lsm_ipc_alloc(sma);
3860 
3861 	if (unlikely(rc))
3862 		return rc;
3863 	rc = call_int_hook(sem_alloc_security, sma);
3864 	if (unlikely(rc))
3865 		security_sem_free(sma);
3866 	return rc;
3867 }
3868 
3869 /**
3870  * security_sem_free() - Free a sysv semaphore LSM blob
3871  * @sma: sysv ipc permission structure
3872  *
3873  * Deallocate security structure @sma->security for the semaphore.
3874  */
3875 void security_sem_free(struct kern_ipc_perm *sma)
3876 {
3877 	call_void_hook(sem_free_security, sma);
3878 	kfree(sma->security);
3879 	sma->security = NULL;
3880 }
3881 
3882 /**
3883  * security_sem_associate() - Check if a sysv semaphore operation is allowed
3884  * @sma: sysv ipc permission structure
3885  * @semflg: operation flags
3886  *
3887  * Check permission when a semaphore is requested through the semget system
3888  * call. This hook is only called when returning the semaphore identifier for
3889  * an existing semaphore, not when a new one must be created.
3890  *
3891  * Return: Returns 0 if permission is granted.
3892  */
3893 int security_sem_associate(struct kern_ipc_perm *sma, int semflg)
3894 {
3895 	return call_int_hook(sem_associate, sma, semflg);
3896 }
3897 
3898 /**
3899  * security_sem_semctl() - Check if a sysv semaphore operation is allowed
3900  * @sma: sysv ipc permission structure
3901  * @cmd: operation
3902  *
3903  * Check permission when a semaphore operation specified by @cmd is to be
3904  * performed on the semaphore.
3905  *
3906  * Return: Returns 0 if permission is granted.
3907  */
3908 int security_sem_semctl(struct kern_ipc_perm *sma, int cmd)
3909 {
3910 	return call_int_hook(sem_semctl, sma, cmd);
3911 }
3912 
3913 /**
3914  * security_sem_semop() - Check if a sysv semaphore operation is allowed
3915  * @sma: sysv ipc permission structure
3916  * @sops: operations to perform
3917  * @nsops: number of operations
3918  * @alter: flag indicating changes will be made
3919  *
3920  * Check permissions before performing operations on members of the semaphore
3921  * set. If the @alter flag is nonzero, the semaphore set may be modified.
3922  *
3923  * Return: Returns 0 if permission is granted.
3924  */
3925 int security_sem_semop(struct kern_ipc_perm *sma, struct sembuf *sops,
3926 		       unsigned nsops, int alter)
3927 {
3928 	return call_int_hook(sem_semop, sma, sops, nsops, alter);
3929 }
3930 
3931 /**
3932  * security_d_instantiate() - Populate an inode's LSM state based on a dentry
3933  * @dentry: dentry
3934  * @inode: inode
3935  *
3936  * Fill in @inode security information for a @dentry if allowed.
3937  */
3938 void security_d_instantiate(struct dentry *dentry, struct inode *inode)
3939 {
3940 	if (unlikely(inode && IS_PRIVATE(inode)))
3941 		return;
3942 	call_void_hook(d_instantiate, dentry, inode);
3943 }
3944 EXPORT_SYMBOL(security_d_instantiate);
3945 
3946 /*
3947  * Please keep this in sync with it's counterpart in security/lsm_syscalls.c
3948  */
3949 
3950 /**
3951  * security_getselfattr - Read an LSM attribute of the current process.
3952  * @attr: which attribute to return
3953  * @uctx: the user-space destination for the information, or NULL
3954  * @size: pointer to the size of space available to receive the data
3955  * @flags: special handling options. LSM_FLAG_SINGLE indicates that only
3956  * attributes associated with the LSM identified in the passed @ctx be
3957  * reported.
3958  *
3959  * A NULL value for @uctx can be used to get both the number of attributes
3960  * and the size of the data.
3961  *
3962  * Returns the number of attributes found on success, negative value
3963  * on error. @size is reset to the total size of the data.
3964  * If @size is insufficient to contain the data -E2BIG is returned.
3965  */
3966 int security_getselfattr(unsigned int attr, struct lsm_ctx __user *uctx,
3967 			 u32 __user *size, u32 flags)
3968 {
3969 	struct security_hook_list *hp;
3970 	struct lsm_ctx lctx = { .id = LSM_ID_UNDEF, };
3971 	u8 __user *base = (u8 __user *)uctx;
3972 	u32 entrysize;
3973 	u32 total = 0;
3974 	u32 left;
3975 	bool toobig = false;
3976 	bool single = false;
3977 	int count = 0;
3978 	int rc;
3979 
3980 	if (attr == LSM_ATTR_UNDEF)
3981 		return -EINVAL;
3982 	if (size == NULL)
3983 		return -EINVAL;
3984 	if (get_user(left, size))
3985 		return -EFAULT;
3986 
3987 	if (flags) {
3988 		/*
3989 		 * Only flag supported is LSM_FLAG_SINGLE
3990 		 */
3991 		if (flags != LSM_FLAG_SINGLE || !uctx)
3992 			return -EINVAL;
3993 		if (copy_from_user(&lctx, uctx, sizeof(lctx)))
3994 			return -EFAULT;
3995 		/*
3996 		 * If the LSM ID isn't specified it is an error.
3997 		 */
3998 		if (lctx.id == LSM_ID_UNDEF)
3999 			return -EINVAL;
4000 		single = true;
4001 	}
4002 
4003 	/*
4004 	 * In the usual case gather all the data from the LSMs.
4005 	 * In the single case only get the data from the LSM specified.
4006 	 */
4007 	hlist_for_each_entry(hp, &security_hook_heads.getselfattr, list) {
4008 		if (single && lctx.id != hp->lsmid->id)
4009 			continue;
4010 		entrysize = left;
4011 		if (base)
4012 			uctx = (struct lsm_ctx __user *)(base + total);
4013 		rc = hp->hook.getselfattr(attr, uctx, &entrysize, flags);
4014 		if (rc == -EOPNOTSUPP) {
4015 			rc = 0;
4016 			continue;
4017 		}
4018 		if (rc == -E2BIG) {
4019 			rc = 0;
4020 			left = 0;
4021 			toobig = true;
4022 		} else if (rc < 0)
4023 			return rc;
4024 		else
4025 			left -= entrysize;
4026 
4027 		total += entrysize;
4028 		count += rc;
4029 		if (single)
4030 			break;
4031 	}
4032 	if (put_user(total, size))
4033 		return -EFAULT;
4034 	if (toobig)
4035 		return -E2BIG;
4036 	if (count == 0)
4037 		return LSM_RET_DEFAULT(getselfattr);
4038 	return count;
4039 }
4040 
4041 /*
4042  * Please keep this in sync with it's counterpart in security/lsm_syscalls.c
4043  */
4044 
4045 /**
4046  * security_setselfattr - Set an LSM attribute on the current process.
4047  * @attr: which attribute to set
4048  * @uctx: the user-space source for the information
4049  * @size: the size of the data
4050  * @flags: reserved for future use, must be 0
4051  *
4052  * Set an LSM attribute for the current process. The LSM, attribute
4053  * and new value are included in @uctx.
4054  *
4055  * Returns 0 on success, -EINVAL if the input is inconsistent, -EFAULT
4056  * if the user buffer is inaccessible, E2BIG if size is too big, or an
4057  * LSM specific failure.
4058  */
4059 int security_setselfattr(unsigned int attr, struct lsm_ctx __user *uctx,
4060 			 u32 size, u32 flags)
4061 {
4062 	struct security_hook_list *hp;
4063 	struct lsm_ctx *lctx;
4064 	int rc = LSM_RET_DEFAULT(setselfattr);
4065 	u64 required_len;
4066 
4067 	if (flags)
4068 		return -EINVAL;
4069 	if (size < sizeof(*lctx))
4070 		return -EINVAL;
4071 	if (size > PAGE_SIZE)
4072 		return -E2BIG;
4073 
4074 	lctx = memdup_user(uctx, size);
4075 	if (IS_ERR(lctx))
4076 		return PTR_ERR(lctx);
4077 
4078 	if (size < lctx->len ||
4079 	    check_add_overflow(sizeof(*lctx), lctx->ctx_len, &required_len) ||
4080 	    lctx->len < required_len) {
4081 		rc = -EINVAL;
4082 		goto free_out;
4083 	}
4084 
4085 	hlist_for_each_entry(hp, &security_hook_heads.setselfattr, list)
4086 		if ((hp->lsmid->id) == lctx->id) {
4087 			rc = hp->hook.setselfattr(attr, lctx, size, flags);
4088 			break;
4089 		}
4090 
4091 free_out:
4092 	kfree(lctx);
4093 	return rc;
4094 }
4095 
4096 /**
4097  * security_getprocattr() - Read an attribute for a task
4098  * @p: the task
4099  * @lsmid: LSM identification
4100  * @name: attribute name
4101  * @value: attribute value
4102  *
4103  * Read attribute @name for task @p and store it into @value if allowed.
4104  *
4105  * Return: Returns the length of @value on success, a negative value otherwise.
4106  */
4107 int security_getprocattr(struct task_struct *p, int lsmid, const char *name,
4108 			 char **value)
4109 {
4110 	struct security_hook_list *hp;
4111 
4112 	hlist_for_each_entry(hp, &security_hook_heads.getprocattr, list) {
4113 		if (lsmid != 0 && lsmid != hp->lsmid->id)
4114 			continue;
4115 		return hp->hook.getprocattr(p, name, value);
4116 	}
4117 	return LSM_RET_DEFAULT(getprocattr);
4118 }
4119 
4120 /**
4121  * security_setprocattr() - Set an attribute for a task
4122  * @lsmid: LSM identification
4123  * @name: attribute name
4124  * @value: attribute value
4125  * @size: attribute value size
4126  *
4127  * Write (set) the current task's attribute @name to @value, size @size if
4128  * allowed.
4129  *
4130  * Return: Returns bytes written on success, a negative value otherwise.
4131  */
4132 int security_setprocattr(int lsmid, const char *name, void *value, size_t size)
4133 {
4134 	struct security_hook_list *hp;
4135 
4136 	hlist_for_each_entry(hp, &security_hook_heads.setprocattr, list) {
4137 		if (lsmid != 0 && lsmid != hp->lsmid->id)
4138 			continue;
4139 		return hp->hook.setprocattr(name, value, size);
4140 	}
4141 	return LSM_RET_DEFAULT(setprocattr);
4142 }
4143 
4144 /**
4145  * security_netlink_send() - Save info and check if netlink sending is allowed
4146  * @sk: sending socket
4147  * @skb: netlink message
4148  *
4149  * Save security information for a netlink message so that permission checking
4150  * can be performed when the message is processed.  The security information
4151  * can be saved using the eff_cap field of the netlink_skb_parms structure.
4152  * Also may be used to provide fine grained control over message transmission.
4153  *
4154  * Return: Returns 0 if the information was successfully saved and message is
4155  *         allowed to be transmitted.
4156  */
4157 int security_netlink_send(struct sock *sk, struct sk_buff *skb)
4158 {
4159 	return call_int_hook(netlink_send, sk, skb);
4160 }
4161 
4162 /**
4163  * security_ismaclabel() - Check if the named attribute is a MAC label
4164  * @name: full extended attribute name
4165  *
4166  * Check if the extended attribute specified by @name represents a MAC label.
4167  *
4168  * Return: Returns 1 if name is a MAC attribute otherwise returns 0.
4169  */
4170 int security_ismaclabel(const char *name)
4171 {
4172 	return call_int_hook(ismaclabel, name);
4173 }
4174 EXPORT_SYMBOL(security_ismaclabel);
4175 
4176 /**
4177  * security_secid_to_secctx() - Convert a secid to a secctx
4178  * @secid: secid
4179  * @secdata: secctx
4180  * @seclen: secctx length
4181  *
4182  * Convert secid to security context.  If @secdata is NULL the length of the
4183  * result will be returned in @seclen, but no @secdata will be returned.  This
4184  * does mean that the length could change between calls to check the length and
4185  * the next call which actually allocates and returns the @secdata.
4186  *
4187  * Return: Return 0 on success, error on failure.
4188  */
4189 int security_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
4190 {
4191 	return call_int_hook(secid_to_secctx, secid, secdata, seclen);
4192 }
4193 EXPORT_SYMBOL(security_secid_to_secctx);
4194 
4195 /**
4196  * security_secctx_to_secid() - Convert a secctx to a secid
4197  * @secdata: secctx
4198  * @seclen: length of secctx
4199  * @secid: secid
4200  *
4201  * Convert security context to secid.
4202  *
4203  * Return: Returns 0 on success, error on failure.
4204  */
4205 int security_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
4206 {
4207 	*secid = 0;
4208 	return call_int_hook(secctx_to_secid, secdata, seclen, secid);
4209 }
4210 EXPORT_SYMBOL(security_secctx_to_secid);
4211 
4212 /**
4213  * security_release_secctx() - Free a secctx buffer
4214  * @secdata: secctx
4215  * @seclen: length of secctx
4216  *
4217  * Release the security context.
4218  */
4219 void security_release_secctx(char *secdata, u32 seclen)
4220 {
4221 	call_void_hook(release_secctx, secdata, seclen);
4222 }
4223 EXPORT_SYMBOL(security_release_secctx);
4224 
4225 /**
4226  * security_inode_invalidate_secctx() - Invalidate an inode's security label
4227  * @inode: inode
4228  *
4229  * Notify the security module that it must revalidate the security context of
4230  * an inode.
4231  */
4232 void security_inode_invalidate_secctx(struct inode *inode)
4233 {
4234 	call_void_hook(inode_invalidate_secctx, inode);
4235 }
4236 EXPORT_SYMBOL(security_inode_invalidate_secctx);
4237 
4238 /**
4239  * security_inode_notifysecctx() - Notify the LSM of an inode's security label
4240  * @inode: inode
4241  * @ctx: secctx
4242  * @ctxlen: length of secctx
4243  *
4244  * Notify the security module of what the security context of an inode should
4245  * be.  Initializes the incore security context managed by the security module
4246  * for this inode.  Example usage: NFS client invokes this hook to initialize
4247  * the security context in its incore inode to the value provided by the server
4248  * for the file when the server returned the file's attributes to the client.
4249  * Must be called with inode->i_mutex locked.
4250  *
4251  * Return: Returns 0 on success, error on failure.
4252  */
4253 int security_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen)
4254 {
4255 	return call_int_hook(inode_notifysecctx, inode, ctx, ctxlen);
4256 }
4257 EXPORT_SYMBOL(security_inode_notifysecctx);
4258 
4259 /**
4260  * security_inode_setsecctx() - Change the security label of an inode
4261  * @dentry: inode
4262  * @ctx: secctx
4263  * @ctxlen: length of secctx
4264  *
4265  * Change the security context of an inode.  Updates the incore security
4266  * context managed by the security module and invokes the fs code as needed
4267  * (via __vfs_setxattr_noperm) to update any backing xattrs that represent the
4268  * context.  Example usage: NFS server invokes this hook to change the security
4269  * context in its incore inode and on the backing filesystem to a value
4270  * provided by the client on a SETATTR operation.  Must be called with
4271  * inode->i_mutex locked.
4272  *
4273  * Return: Returns 0 on success, error on failure.
4274  */
4275 int security_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen)
4276 {
4277 	return call_int_hook(inode_setsecctx, dentry, ctx, ctxlen);
4278 }
4279 EXPORT_SYMBOL(security_inode_setsecctx);
4280 
4281 /**
4282  * security_inode_getsecctx() - Get the security label of an inode
4283  * @inode: inode
4284  * @ctx: secctx
4285  * @ctxlen: length of secctx
4286  *
4287  * On success, returns 0 and fills out @ctx and @ctxlen with the security
4288  * context for the given @inode.
4289  *
4290  * Return: Returns 0 on success, error on failure.
4291  */
4292 int security_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen)
4293 {
4294 	return call_int_hook(inode_getsecctx, inode, ctx, ctxlen);
4295 }
4296 EXPORT_SYMBOL(security_inode_getsecctx);
4297 
4298 #ifdef CONFIG_WATCH_QUEUE
4299 /**
4300  * security_post_notification() - Check if a watch notification can be posted
4301  * @w_cred: credentials of the task that set the watch
4302  * @cred: credentials of the task which triggered the watch
4303  * @n: the notification
4304  *
4305  * Check to see if a watch notification can be posted to a particular queue.
4306  *
4307  * Return: Returns 0 if permission is granted.
4308  */
4309 int security_post_notification(const struct cred *w_cred,
4310 			       const struct cred *cred,
4311 			       struct watch_notification *n)
4312 {
4313 	return call_int_hook(post_notification, w_cred, cred, n);
4314 }
4315 #endif /* CONFIG_WATCH_QUEUE */
4316 
4317 #ifdef CONFIG_KEY_NOTIFICATIONS
4318 /**
4319  * security_watch_key() - Check if a task is allowed to watch for key events
4320  * @key: the key to watch
4321  *
4322  * Check to see if a process is allowed to watch for event notifications from
4323  * a key or keyring.
4324  *
4325  * Return: Returns 0 if permission is granted.
4326  */
4327 int security_watch_key(struct key *key)
4328 {
4329 	return call_int_hook(watch_key, key);
4330 }
4331 #endif /* CONFIG_KEY_NOTIFICATIONS */
4332 
4333 #ifdef CONFIG_SECURITY_NETWORK
4334 /**
4335  * security_unix_stream_connect() - Check if a AF_UNIX stream is allowed
4336  * @sock: originating sock
4337  * @other: peer sock
4338  * @newsk: new sock
4339  *
4340  * Check permissions before establishing a Unix domain stream connection
4341  * between @sock and @other.
4342  *
4343  * The @unix_stream_connect and @unix_may_send hooks were necessary because
4344  * Linux provides an alternative to the conventional file name space for Unix
4345  * domain sockets.  Whereas binding and connecting to sockets in the file name
4346  * space is mediated by the typical file permissions (and caught by the mknod
4347  * and permission hooks in inode_security_ops), binding and connecting to
4348  * sockets in the abstract name space is completely unmediated.  Sufficient
4349  * control of Unix domain sockets in the abstract name space isn't possible
4350  * using only the socket layer hooks, since we need to know the actual target
4351  * socket, which is not looked up until we are inside the af_unix code.
4352  *
4353  * Return: Returns 0 if permission is granted.
4354  */
4355 int security_unix_stream_connect(struct sock *sock, struct sock *other,
4356 				 struct sock *newsk)
4357 {
4358 	return call_int_hook(unix_stream_connect, sock, other, newsk);
4359 }
4360 EXPORT_SYMBOL(security_unix_stream_connect);
4361 
4362 /**
4363  * security_unix_may_send() - Check if AF_UNIX socket can send datagrams
4364  * @sock: originating sock
4365  * @other: peer sock
4366  *
4367  * Check permissions before connecting or sending datagrams from @sock to
4368  * @other.
4369  *
4370  * The @unix_stream_connect and @unix_may_send hooks were necessary because
4371  * Linux provides an alternative to the conventional file name space for Unix
4372  * domain sockets.  Whereas binding and connecting to sockets in the file name
4373  * space is mediated by the typical file permissions (and caught by the mknod
4374  * and permission hooks in inode_security_ops), binding and connecting to
4375  * sockets in the abstract name space is completely unmediated.  Sufficient
4376  * control of Unix domain sockets in the abstract name space isn't possible
4377  * using only the socket layer hooks, since we need to know the actual target
4378  * socket, which is not looked up until we are inside the af_unix code.
4379  *
4380  * Return: Returns 0 if permission is granted.
4381  */
4382 int security_unix_may_send(struct socket *sock,  struct socket *other)
4383 {
4384 	return call_int_hook(unix_may_send, sock, other);
4385 }
4386 EXPORT_SYMBOL(security_unix_may_send);
4387 
4388 /**
4389  * security_socket_create() - Check if creating a new socket is allowed
4390  * @family: protocol family
4391  * @type: communications type
4392  * @protocol: requested protocol
4393  * @kern: set to 1 if a kernel socket is requested
4394  *
4395  * Check permissions prior to creating a new socket.
4396  *
4397  * Return: Returns 0 if permission is granted.
4398  */
4399 int security_socket_create(int family, int type, int protocol, int kern)
4400 {
4401 	return call_int_hook(socket_create, family, type, protocol, kern);
4402 }
4403 
4404 /**
4405  * security_socket_post_create() - Initialize a newly created socket
4406  * @sock: socket
4407  * @family: protocol family
4408  * @type: communications type
4409  * @protocol: requested protocol
4410  * @kern: set to 1 if a kernel socket is requested
4411  *
4412  * This hook allows a module to update or allocate a per-socket security
4413  * structure. Note that the security field was not added directly to the socket
4414  * structure, but rather, the socket security information is stored in the
4415  * associated inode.  Typically, the inode alloc_security hook will allocate
4416  * and attach security information to SOCK_INODE(sock)->i_security.  This hook
4417  * may be used to update the SOCK_INODE(sock)->i_security field with additional
4418  * information that wasn't available when the inode was allocated.
4419  *
4420  * Return: Returns 0 if permission is granted.
4421  */
4422 int security_socket_post_create(struct socket *sock, int family,
4423 				int type, int protocol, int kern)
4424 {
4425 	return call_int_hook(socket_post_create, sock, family, type,
4426 			     protocol, kern);
4427 }
4428 
4429 /**
4430  * security_socket_socketpair() - Check if creating a socketpair is allowed
4431  * @socka: first socket
4432  * @sockb: second socket
4433  *
4434  * Check permissions before creating a fresh pair of sockets.
4435  *
4436  * Return: Returns 0 if permission is granted and the connection was
4437  *         established.
4438  */
4439 int security_socket_socketpair(struct socket *socka, struct socket *sockb)
4440 {
4441 	return call_int_hook(socket_socketpair, socka, sockb);
4442 }
4443 EXPORT_SYMBOL(security_socket_socketpair);
4444 
4445 /**
4446  * security_socket_bind() - Check if a socket bind operation is allowed
4447  * @sock: socket
4448  * @address: requested bind address
4449  * @addrlen: length of address
4450  *
4451  * Check permission before socket protocol layer bind operation is performed
4452  * and the socket @sock is bound to the address specified in the @address
4453  * parameter.
4454  *
4455  * Return: Returns 0 if permission is granted.
4456  */
4457 int security_socket_bind(struct socket *sock,
4458 			 struct sockaddr *address, int addrlen)
4459 {
4460 	return call_int_hook(socket_bind, sock, address, addrlen);
4461 }
4462 
4463 /**
4464  * security_socket_connect() - Check if a socket connect operation is allowed
4465  * @sock: socket
4466  * @address: address of remote connection point
4467  * @addrlen: length of address
4468  *
4469  * Check permission before socket protocol layer connect operation attempts to
4470  * connect socket @sock to a remote address, @address.
4471  *
4472  * Return: Returns 0 if permission is granted.
4473  */
4474 int security_socket_connect(struct socket *sock,
4475 			    struct sockaddr *address, int addrlen)
4476 {
4477 	return call_int_hook(socket_connect, sock, address, addrlen);
4478 }
4479 
4480 /**
4481  * security_socket_listen() - Check if a socket is allowed to listen
4482  * @sock: socket
4483  * @backlog: connection queue size
4484  *
4485  * Check permission before socket protocol layer listen operation.
4486  *
4487  * Return: Returns 0 if permission is granted.
4488  */
4489 int security_socket_listen(struct socket *sock, int backlog)
4490 {
4491 	return call_int_hook(socket_listen, sock, backlog);
4492 }
4493 
4494 /**
4495  * security_socket_accept() - Check if a socket is allowed to accept connections
4496  * @sock: listening socket
4497  * @newsock: newly creation connection socket
4498  *
4499  * Check permission before accepting a new connection.  Note that the new
4500  * socket, @newsock, has been created and some information copied to it, but
4501  * the accept operation has not actually been performed.
4502  *
4503  * Return: Returns 0 if permission is granted.
4504  */
4505 int security_socket_accept(struct socket *sock, struct socket *newsock)
4506 {
4507 	return call_int_hook(socket_accept, sock, newsock);
4508 }
4509 
4510 /**
4511  * security_socket_sendmsg() - Check if sending a message is allowed
4512  * @sock: sending socket
4513  * @msg: message to send
4514  * @size: size of message
4515  *
4516  * Check permission before transmitting a message to another socket.
4517  *
4518  * Return: Returns 0 if permission is granted.
4519  */
4520 int security_socket_sendmsg(struct socket *sock, struct msghdr *msg, int size)
4521 {
4522 	return call_int_hook(socket_sendmsg, sock, msg, size);
4523 }
4524 
4525 /**
4526  * security_socket_recvmsg() - Check if receiving a message is allowed
4527  * @sock: receiving socket
4528  * @msg: message to receive
4529  * @size: size of message
4530  * @flags: operational flags
4531  *
4532  * Check permission before receiving a message from a socket.
4533  *
4534  * Return: Returns 0 if permission is granted.
4535  */
4536 int security_socket_recvmsg(struct socket *sock, struct msghdr *msg,
4537 			    int size, int flags)
4538 {
4539 	return call_int_hook(socket_recvmsg, sock, msg, size, flags);
4540 }
4541 
4542 /**
4543  * security_socket_getsockname() - Check if reading the socket addr is allowed
4544  * @sock: socket
4545  *
4546  * Check permission before reading the local address (name) of the socket
4547  * object.
4548  *
4549  * Return: Returns 0 if permission is granted.
4550  */
4551 int security_socket_getsockname(struct socket *sock)
4552 {
4553 	return call_int_hook(socket_getsockname, sock);
4554 }
4555 
4556 /**
4557  * security_socket_getpeername() - Check if reading the peer's addr is allowed
4558  * @sock: socket
4559  *
4560  * Check permission before the remote address (name) of a socket object.
4561  *
4562  * Return: Returns 0 if permission is granted.
4563  */
4564 int security_socket_getpeername(struct socket *sock)
4565 {
4566 	return call_int_hook(socket_getpeername, sock);
4567 }
4568 
4569 /**
4570  * security_socket_getsockopt() - Check if reading a socket option is allowed
4571  * @sock: socket
4572  * @level: option's protocol level
4573  * @optname: option name
4574  *
4575  * Check permissions before retrieving the options associated with socket
4576  * @sock.
4577  *
4578  * Return: Returns 0 if permission is granted.
4579  */
4580 int security_socket_getsockopt(struct socket *sock, int level, int optname)
4581 {
4582 	return call_int_hook(socket_getsockopt, sock, level, optname);
4583 }
4584 
4585 /**
4586  * security_socket_setsockopt() - Check if setting a socket option is allowed
4587  * @sock: socket
4588  * @level: option's protocol level
4589  * @optname: option name
4590  *
4591  * Check permissions before setting the options associated with socket @sock.
4592  *
4593  * Return: Returns 0 if permission is granted.
4594  */
4595 int security_socket_setsockopt(struct socket *sock, int level, int optname)
4596 {
4597 	return call_int_hook(socket_setsockopt, sock, level, optname);
4598 }
4599 
4600 /**
4601  * security_socket_shutdown() - Checks if shutting down the socket is allowed
4602  * @sock: socket
4603  * @how: flag indicating how sends and receives are handled
4604  *
4605  * Checks permission before all or part of a connection on the socket @sock is
4606  * shut down.
4607  *
4608  * Return: Returns 0 if permission is granted.
4609  */
4610 int security_socket_shutdown(struct socket *sock, int how)
4611 {
4612 	return call_int_hook(socket_shutdown, sock, how);
4613 }
4614 
4615 /**
4616  * security_sock_rcv_skb() - Check if an incoming network packet is allowed
4617  * @sk: destination sock
4618  * @skb: incoming packet
4619  *
4620  * Check permissions on incoming network packets.  This hook is distinct from
4621  * Netfilter's IP input hooks since it is the first time that the incoming
4622  * sk_buff @skb has been associated with a particular socket, @sk.  Must not
4623  * sleep inside this hook because some callers hold spinlocks.
4624  *
4625  * Return: Returns 0 if permission is granted.
4626  */
4627 int security_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
4628 {
4629 	return call_int_hook(socket_sock_rcv_skb, sk, skb);
4630 }
4631 EXPORT_SYMBOL(security_sock_rcv_skb);
4632 
4633 /**
4634  * security_socket_getpeersec_stream() - Get the remote peer label
4635  * @sock: socket
4636  * @optval: destination buffer
4637  * @optlen: size of peer label copied into the buffer
4638  * @len: maximum size of the destination buffer
4639  *
4640  * This hook allows the security module to provide peer socket security state
4641  * for unix or connected tcp sockets to userspace via getsockopt SO_GETPEERSEC.
4642  * For tcp sockets this can be meaningful if the socket is associated with an
4643  * ipsec SA.
4644  *
4645  * Return: Returns 0 if all is well, otherwise, typical getsockopt return
4646  *         values.
4647  */
4648 int security_socket_getpeersec_stream(struct socket *sock, sockptr_t optval,
4649 				      sockptr_t optlen, unsigned int len)
4650 {
4651 	return call_int_hook(socket_getpeersec_stream, sock, optval, optlen,
4652 			     len);
4653 }
4654 
4655 /**
4656  * security_socket_getpeersec_dgram() - Get the remote peer label
4657  * @sock: socket
4658  * @skb: datagram packet
4659  * @secid: remote peer label secid
4660  *
4661  * This hook allows the security module to provide peer socket security state
4662  * for udp sockets on a per-packet basis to userspace via getsockopt
4663  * SO_GETPEERSEC. The application must first have indicated the IP_PASSSEC
4664  * option via getsockopt. It can then retrieve the security state returned by
4665  * this hook for a packet via the SCM_SECURITY ancillary message type.
4666  *
4667  * Return: Returns 0 on success, error on failure.
4668  */
4669 int security_socket_getpeersec_dgram(struct socket *sock,
4670 				     struct sk_buff *skb, u32 *secid)
4671 {
4672 	return call_int_hook(socket_getpeersec_dgram, sock, skb, secid);
4673 }
4674 EXPORT_SYMBOL(security_socket_getpeersec_dgram);
4675 
4676 /**
4677  * security_sk_alloc() - Allocate and initialize a sock's LSM blob
4678  * @sk: sock
4679  * @family: protocol family
4680  * @priority: gfp flags
4681  *
4682  * Allocate and attach a security structure to the sk->sk_security field, which
4683  * is used to copy security attributes between local stream sockets.
4684  *
4685  * Return: Returns 0 on success, error on failure.
4686  */
4687 int security_sk_alloc(struct sock *sk, int family, gfp_t priority)
4688 {
4689 	return call_int_hook(sk_alloc_security, sk, family, priority);
4690 }
4691 
4692 /**
4693  * security_sk_free() - Free the sock's LSM blob
4694  * @sk: sock
4695  *
4696  * Deallocate security structure.
4697  */
4698 void security_sk_free(struct sock *sk)
4699 {
4700 	call_void_hook(sk_free_security, sk);
4701 }
4702 
4703 /**
4704  * security_sk_clone() - Clone a sock's LSM state
4705  * @sk: original sock
4706  * @newsk: target sock
4707  *
4708  * Clone/copy security structure.
4709  */
4710 void security_sk_clone(const struct sock *sk, struct sock *newsk)
4711 {
4712 	call_void_hook(sk_clone_security, sk, newsk);
4713 }
4714 EXPORT_SYMBOL(security_sk_clone);
4715 
4716 /**
4717  * security_sk_classify_flow() - Set a flow's secid based on socket
4718  * @sk: original socket
4719  * @flic: target flow
4720  *
4721  * Set the target flow's secid to socket's secid.
4722  */
4723 void security_sk_classify_flow(const struct sock *sk, struct flowi_common *flic)
4724 {
4725 	call_void_hook(sk_getsecid, sk, &flic->flowic_secid);
4726 }
4727 EXPORT_SYMBOL(security_sk_classify_flow);
4728 
4729 /**
4730  * security_req_classify_flow() - Set a flow's secid based on request_sock
4731  * @req: request_sock
4732  * @flic: target flow
4733  *
4734  * Sets @flic's secid to @req's secid.
4735  */
4736 void security_req_classify_flow(const struct request_sock *req,
4737 				struct flowi_common *flic)
4738 {
4739 	call_void_hook(req_classify_flow, req, flic);
4740 }
4741 EXPORT_SYMBOL(security_req_classify_flow);
4742 
4743 /**
4744  * security_sock_graft() - Reconcile LSM state when grafting a sock on a socket
4745  * @sk: sock being grafted
4746  * @parent: target parent socket
4747  *
4748  * Sets @parent's inode secid to @sk's secid and update @sk with any necessary
4749  * LSM state from @parent.
4750  */
4751 void security_sock_graft(struct sock *sk, struct socket *parent)
4752 {
4753 	call_void_hook(sock_graft, sk, parent);
4754 }
4755 EXPORT_SYMBOL(security_sock_graft);
4756 
4757 /**
4758  * security_inet_conn_request() - Set request_sock state using incoming connect
4759  * @sk: parent listening sock
4760  * @skb: incoming connection
4761  * @req: new request_sock
4762  *
4763  * Initialize the @req LSM state based on @sk and the incoming connect in @skb.
4764  *
4765  * Return: Returns 0 if permission is granted.
4766  */
4767 int security_inet_conn_request(const struct sock *sk,
4768 			       struct sk_buff *skb, struct request_sock *req)
4769 {
4770 	return call_int_hook(inet_conn_request, sk, skb, req);
4771 }
4772 EXPORT_SYMBOL(security_inet_conn_request);
4773 
4774 /**
4775  * security_inet_csk_clone() - Set new sock LSM state based on request_sock
4776  * @newsk: new sock
4777  * @req: connection request_sock
4778  *
4779  * Set that LSM state of @sock using the LSM state from @req.
4780  */
4781 void security_inet_csk_clone(struct sock *newsk,
4782 			     const struct request_sock *req)
4783 {
4784 	call_void_hook(inet_csk_clone, newsk, req);
4785 }
4786 
4787 /**
4788  * security_inet_conn_established() - Update sock's LSM state with connection
4789  * @sk: sock
4790  * @skb: connection packet
4791  *
4792  * Update @sock's LSM state to represent a new connection from @skb.
4793  */
4794 void security_inet_conn_established(struct sock *sk,
4795 				    struct sk_buff *skb)
4796 {
4797 	call_void_hook(inet_conn_established, sk, skb);
4798 }
4799 EXPORT_SYMBOL(security_inet_conn_established);
4800 
4801 /**
4802  * security_secmark_relabel_packet() - Check if setting a secmark is allowed
4803  * @secid: new secmark value
4804  *
4805  * Check if the process should be allowed to relabel packets to @secid.
4806  *
4807  * Return: Returns 0 if permission is granted.
4808  */
4809 int security_secmark_relabel_packet(u32 secid)
4810 {
4811 	return call_int_hook(secmark_relabel_packet, secid);
4812 }
4813 EXPORT_SYMBOL(security_secmark_relabel_packet);
4814 
4815 /**
4816  * security_secmark_refcount_inc() - Increment the secmark labeling rule count
4817  *
4818  * Tells the LSM to increment the number of secmark labeling rules loaded.
4819  */
4820 void security_secmark_refcount_inc(void)
4821 {
4822 	call_void_hook(secmark_refcount_inc);
4823 }
4824 EXPORT_SYMBOL(security_secmark_refcount_inc);
4825 
4826 /**
4827  * security_secmark_refcount_dec() - Decrement the secmark labeling rule count
4828  *
4829  * Tells the LSM to decrement the number of secmark labeling rules loaded.
4830  */
4831 void security_secmark_refcount_dec(void)
4832 {
4833 	call_void_hook(secmark_refcount_dec);
4834 }
4835 EXPORT_SYMBOL(security_secmark_refcount_dec);
4836 
4837 /**
4838  * security_tun_dev_alloc_security() - Allocate a LSM blob for a TUN device
4839  * @security: pointer to the LSM blob
4840  *
4841  * This hook allows a module to allocate a security structure for a TUN	device,
4842  * returning the pointer in @security.
4843  *
4844  * Return: Returns a zero on success, negative values on failure.
4845  */
4846 int security_tun_dev_alloc_security(void **security)
4847 {
4848 	return call_int_hook(tun_dev_alloc_security, security);
4849 }
4850 EXPORT_SYMBOL(security_tun_dev_alloc_security);
4851 
4852 /**
4853  * security_tun_dev_free_security() - Free a TUN device LSM blob
4854  * @security: LSM blob
4855  *
4856  * This hook allows a module to free the security structure for a TUN device.
4857  */
4858 void security_tun_dev_free_security(void *security)
4859 {
4860 	call_void_hook(tun_dev_free_security, security);
4861 }
4862 EXPORT_SYMBOL(security_tun_dev_free_security);
4863 
4864 /**
4865  * security_tun_dev_create() - Check if creating a TUN device is allowed
4866  *
4867  * Check permissions prior to creating a new TUN device.
4868  *
4869  * Return: Returns 0 if permission is granted.
4870  */
4871 int security_tun_dev_create(void)
4872 {
4873 	return call_int_hook(tun_dev_create);
4874 }
4875 EXPORT_SYMBOL(security_tun_dev_create);
4876 
4877 /**
4878  * security_tun_dev_attach_queue() - Check if attaching a TUN queue is allowed
4879  * @security: TUN device LSM blob
4880  *
4881  * Check permissions prior to attaching to a TUN device queue.
4882  *
4883  * Return: Returns 0 if permission is granted.
4884  */
4885 int security_tun_dev_attach_queue(void *security)
4886 {
4887 	return call_int_hook(tun_dev_attach_queue, security);
4888 }
4889 EXPORT_SYMBOL(security_tun_dev_attach_queue);
4890 
4891 /**
4892  * security_tun_dev_attach() - Update TUN device LSM state on attach
4893  * @sk: associated sock
4894  * @security: TUN device LSM blob
4895  *
4896  * This hook can be used by the module to update any security state associated
4897  * with the TUN device's sock structure.
4898  *
4899  * Return: Returns 0 if permission is granted.
4900  */
4901 int security_tun_dev_attach(struct sock *sk, void *security)
4902 {
4903 	return call_int_hook(tun_dev_attach, sk, security);
4904 }
4905 EXPORT_SYMBOL(security_tun_dev_attach);
4906 
4907 /**
4908  * security_tun_dev_open() - Update TUN device LSM state on open
4909  * @security: TUN device LSM blob
4910  *
4911  * This hook can be used by the module to update any security state associated
4912  * with the TUN device's security structure.
4913  *
4914  * Return: Returns 0 if permission is granted.
4915  */
4916 int security_tun_dev_open(void *security)
4917 {
4918 	return call_int_hook(tun_dev_open, security);
4919 }
4920 EXPORT_SYMBOL(security_tun_dev_open);
4921 
4922 /**
4923  * security_sctp_assoc_request() - Update the LSM on a SCTP association req
4924  * @asoc: SCTP association
4925  * @skb: packet requesting the association
4926  *
4927  * Passes the @asoc and @chunk->skb of the association INIT packet to the LSM.
4928  *
4929  * Return: Returns 0 on success, error on failure.
4930  */
4931 int security_sctp_assoc_request(struct sctp_association *asoc,
4932 				struct sk_buff *skb)
4933 {
4934 	return call_int_hook(sctp_assoc_request, asoc, skb);
4935 }
4936 EXPORT_SYMBOL(security_sctp_assoc_request);
4937 
4938 /**
4939  * security_sctp_bind_connect() - Validate a list of addrs for a SCTP option
4940  * @sk: socket
4941  * @optname: SCTP option to validate
4942  * @address: list of IP addresses to validate
4943  * @addrlen: length of the address list
4944  *
4945  * Validiate permissions required for each address associated with sock	@sk.
4946  * Depending on @optname, the addresses will be treated as either a connect or
4947  * bind service. The @addrlen is calculated on each IPv4 and IPv6 address using
4948  * sizeof(struct sockaddr_in) or sizeof(struct sockaddr_in6).
4949  *
4950  * Return: Returns 0 on success, error on failure.
4951  */
4952 int security_sctp_bind_connect(struct sock *sk, int optname,
4953 			       struct sockaddr *address, int addrlen)
4954 {
4955 	return call_int_hook(sctp_bind_connect, sk, optname, address, addrlen);
4956 }
4957 EXPORT_SYMBOL(security_sctp_bind_connect);
4958 
4959 /**
4960  * security_sctp_sk_clone() - Clone a SCTP sock's LSM state
4961  * @asoc: SCTP association
4962  * @sk: original sock
4963  * @newsk: target sock
4964  *
4965  * Called whenever a new socket is created by accept(2) (i.e. a TCP style
4966  * socket) or when a socket is 'peeled off' e.g userspace calls
4967  * sctp_peeloff(3).
4968  */
4969 void security_sctp_sk_clone(struct sctp_association *asoc, struct sock *sk,
4970 			    struct sock *newsk)
4971 {
4972 	call_void_hook(sctp_sk_clone, asoc, sk, newsk);
4973 }
4974 EXPORT_SYMBOL(security_sctp_sk_clone);
4975 
4976 /**
4977  * security_sctp_assoc_established() - Update LSM state when assoc established
4978  * @asoc: SCTP association
4979  * @skb: packet establishing the association
4980  *
4981  * Passes the @asoc and @chunk->skb of the association COOKIE_ACK packet to the
4982  * security module.
4983  *
4984  * Return: Returns 0 if permission is granted.
4985  */
4986 int security_sctp_assoc_established(struct sctp_association *asoc,
4987 				    struct sk_buff *skb)
4988 {
4989 	return call_int_hook(sctp_assoc_established, asoc, skb);
4990 }
4991 EXPORT_SYMBOL(security_sctp_assoc_established);
4992 
4993 /**
4994  * security_mptcp_add_subflow() - Inherit the LSM label from the MPTCP socket
4995  * @sk: the owning MPTCP socket
4996  * @ssk: the new subflow
4997  *
4998  * Update the labeling for the given MPTCP subflow, to match the one of the
4999  * owning MPTCP socket. This hook has to be called after the socket creation and
5000  * initialization via the security_socket_create() and
5001  * security_socket_post_create() LSM hooks.
5002  *
5003  * Return: Returns 0 on success or a negative error code on failure.
5004  */
5005 int security_mptcp_add_subflow(struct sock *sk, struct sock *ssk)
5006 {
5007 	return call_int_hook(mptcp_add_subflow, sk, ssk);
5008 }
5009 
5010 #endif	/* CONFIG_SECURITY_NETWORK */
5011 
5012 #ifdef CONFIG_SECURITY_INFINIBAND
5013 /**
5014  * security_ib_pkey_access() - Check if access to an IB pkey is allowed
5015  * @sec: LSM blob
5016  * @subnet_prefix: subnet prefix of the port
5017  * @pkey: IB pkey
5018  *
5019  * Check permission to access a pkey when modifying a QP.
5020  *
5021  * Return: Returns 0 if permission is granted.
5022  */
5023 int security_ib_pkey_access(void *sec, u64 subnet_prefix, u16 pkey)
5024 {
5025 	return call_int_hook(ib_pkey_access, sec, subnet_prefix, pkey);
5026 }
5027 EXPORT_SYMBOL(security_ib_pkey_access);
5028 
5029 /**
5030  * security_ib_endport_manage_subnet() - Check if SMPs traffic is allowed
5031  * @sec: LSM blob
5032  * @dev_name: IB device name
5033  * @port_num: port number
5034  *
5035  * Check permissions to send and receive SMPs on a end port.
5036  *
5037  * Return: Returns 0 if permission is granted.
5038  */
5039 int security_ib_endport_manage_subnet(void *sec,
5040 				      const char *dev_name, u8 port_num)
5041 {
5042 	return call_int_hook(ib_endport_manage_subnet, sec, dev_name, port_num);
5043 }
5044 EXPORT_SYMBOL(security_ib_endport_manage_subnet);
5045 
5046 /**
5047  * security_ib_alloc_security() - Allocate an Infiniband LSM blob
5048  * @sec: LSM blob
5049  *
5050  * Allocate a security structure for Infiniband objects.
5051  *
5052  * Return: Returns 0 on success, non-zero on failure.
5053  */
5054 int security_ib_alloc_security(void **sec)
5055 {
5056 	return call_int_hook(ib_alloc_security, sec);
5057 }
5058 EXPORT_SYMBOL(security_ib_alloc_security);
5059 
5060 /**
5061  * security_ib_free_security() - Free an Infiniband LSM blob
5062  * @sec: LSM blob
5063  *
5064  * Deallocate an Infiniband security structure.
5065  */
5066 void security_ib_free_security(void *sec)
5067 {
5068 	call_void_hook(ib_free_security, sec);
5069 }
5070 EXPORT_SYMBOL(security_ib_free_security);
5071 #endif	/* CONFIG_SECURITY_INFINIBAND */
5072 
5073 #ifdef CONFIG_SECURITY_NETWORK_XFRM
5074 /**
5075  * security_xfrm_policy_alloc() - Allocate a xfrm policy LSM blob
5076  * @ctxp: xfrm security context being added to the SPD
5077  * @sec_ctx: security label provided by userspace
5078  * @gfp: gfp flags
5079  *
5080  * Allocate a security structure to the xp->security field; the security field
5081  * is initialized to NULL when the xfrm_policy is allocated.
5082  *
5083  * Return:  Return 0 if operation was successful.
5084  */
5085 int security_xfrm_policy_alloc(struct xfrm_sec_ctx **ctxp,
5086 			       struct xfrm_user_sec_ctx *sec_ctx,
5087 			       gfp_t gfp)
5088 {
5089 	return call_int_hook(xfrm_policy_alloc_security, ctxp, sec_ctx, gfp);
5090 }
5091 EXPORT_SYMBOL(security_xfrm_policy_alloc);
5092 
5093 /**
5094  * security_xfrm_policy_clone() - Clone xfrm policy LSM state
5095  * @old_ctx: xfrm security context
5096  * @new_ctxp: target xfrm security context
5097  *
5098  * Allocate a security structure in new_ctxp that contains the information from
5099  * the old_ctx structure.
5100  *
5101  * Return: Return 0 if operation was successful.
5102  */
5103 int security_xfrm_policy_clone(struct xfrm_sec_ctx *old_ctx,
5104 			       struct xfrm_sec_ctx **new_ctxp)
5105 {
5106 	return call_int_hook(xfrm_policy_clone_security, old_ctx, new_ctxp);
5107 }
5108 
5109 /**
5110  * security_xfrm_policy_free() - Free a xfrm security context
5111  * @ctx: xfrm security context
5112  *
5113  * Free LSM resources associated with @ctx.
5114  */
5115 void security_xfrm_policy_free(struct xfrm_sec_ctx *ctx)
5116 {
5117 	call_void_hook(xfrm_policy_free_security, ctx);
5118 }
5119 EXPORT_SYMBOL(security_xfrm_policy_free);
5120 
5121 /**
5122  * security_xfrm_policy_delete() - Check if deleting a xfrm policy is allowed
5123  * @ctx: xfrm security context
5124  *
5125  * Authorize deletion of a SPD entry.
5126  *
5127  * Return: Returns 0 if permission is granted.
5128  */
5129 int security_xfrm_policy_delete(struct xfrm_sec_ctx *ctx)
5130 {
5131 	return call_int_hook(xfrm_policy_delete_security, ctx);
5132 }
5133 
5134 /**
5135  * security_xfrm_state_alloc() - Allocate a xfrm state LSM blob
5136  * @x: xfrm state being added to the SAD
5137  * @sec_ctx: security label provided by userspace
5138  *
5139  * Allocate a security structure to the @x->security field; the security field
5140  * is initialized to NULL when the xfrm_state is allocated. Set the context to
5141  * correspond to @sec_ctx.
5142  *
5143  * Return: Return 0 if operation was successful.
5144  */
5145 int security_xfrm_state_alloc(struct xfrm_state *x,
5146 			      struct xfrm_user_sec_ctx *sec_ctx)
5147 {
5148 	return call_int_hook(xfrm_state_alloc, x, sec_ctx);
5149 }
5150 EXPORT_SYMBOL(security_xfrm_state_alloc);
5151 
5152 /**
5153  * security_xfrm_state_alloc_acquire() - Allocate a xfrm state LSM blob
5154  * @x: xfrm state being added to the SAD
5155  * @polsec: associated policy's security context
5156  * @secid: secid from the flow
5157  *
5158  * Allocate a security structure to the x->security field; the security field
5159  * is initialized to NULL when the xfrm_state is allocated.  Set the context to
5160  * correspond to secid.
5161  *
5162  * Return: Returns 0 if operation was successful.
5163  */
5164 int security_xfrm_state_alloc_acquire(struct xfrm_state *x,
5165 				      struct xfrm_sec_ctx *polsec, u32 secid)
5166 {
5167 	return call_int_hook(xfrm_state_alloc_acquire, x, polsec, secid);
5168 }
5169 
5170 /**
5171  * security_xfrm_state_delete() - Check if deleting a xfrm state is allowed
5172  * @x: xfrm state
5173  *
5174  * Authorize deletion of x->security.
5175  *
5176  * Return: Returns 0 if permission is granted.
5177  */
5178 int security_xfrm_state_delete(struct xfrm_state *x)
5179 {
5180 	return call_int_hook(xfrm_state_delete_security, x);
5181 }
5182 EXPORT_SYMBOL(security_xfrm_state_delete);
5183 
5184 /**
5185  * security_xfrm_state_free() - Free a xfrm state
5186  * @x: xfrm state
5187  *
5188  * Deallocate x->security.
5189  */
5190 void security_xfrm_state_free(struct xfrm_state *x)
5191 {
5192 	call_void_hook(xfrm_state_free_security, x);
5193 }
5194 
5195 /**
5196  * security_xfrm_policy_lookup() - Check if using a xfrm policy is allowed
5197  * @ctx: target xfrm security context
5198  * @fl_secid: flow secid used to authorize access
5199  *
5200  * Check permission when a flow selects a xfrm_policy for processing XFRMs on a
5201  * packet.  The hook is called when selecting either a per-socket policy or a
5202  * generic xfrm policy.
5203  *
5204  * Return: Return 0 if permission is granted, -ESRCH otherwise, or -errno on
5205  *         other errors.
5206  */
5207 int security_xfrm_policy_lookup(struct xfrm_sec_ctx *ctx, u32 fl_secid)
5208 {
5209 	return call_int_hook(xfrm_policy_lookup, ctx, fl_secid);
5210 }
5211 
5212 /**
5213  * security_xfrm_state_pol_flow_match() - Check for a xfrm match
5214  * @x: xfrm state to match
5215  * @xp: xfrm policy to check for a match
5216  * @flic: flow to check for a match.
5217  *
5218  * Check @xp and @flic for a match with @x.
5219  *
5220  * Return: Returns 1 if there is a match.
5221  */
5222 int security_xfrm_state_pol_flow_match(struct xfrm_state *x,
5223 				       struct xfrm_policy *xp,
5224 				       const struct flowi_common *flic)
5225 {
5226 	struct security_hook_list *hp;
5227 	int rc = LSM_RET_DEFAULT(xfrm_state_pol_flow_match);
5228 
5229 	/*
5230 	 * Since this function is expected to return 0 or 1, the judgment
5231 	 * becomes difficult if multiple LSMs supply this call. Fortunately,
5232 	 * we can use the first LSM's judgment because currently only SELinux
5233 	 * supplies this call.
5234 	 *
5235 	 * For speed optimization, we explicitly break the loop rather than
5236 	 * using the macro
5237 	 */
5238 	hlist_for_each_entry(hp, &security_hook_heads.xfrm_state_pol_flow_match,
5239 			     list) {
5240 		rc = hp->hook.xfrm_state_pol_flow_match(x, xp, flic);
5241 		break;
5242 	}
5243 	return rc;
5244 }
5245 
5246 /**
5247  * security_xfrm_decode_session() - Determine the xfrm secid for a packet
5248  * @skb: xfrm packet
5249  * @secid: secid
5250  *
5251  * Decode the packet in @skb and return the security label in @secid.
5252  *
5253  * Return: Return 0 if all xfrms used have the same secid.
5254  */
5255 int security_xfrm_decode_session(struct sk_buff *skb, u32 *secid)
5256 {
5257 	return call_int_hook(xfrm_decode_session, skb, secid, 1);
5258 }
5259 
5260 void security_skb_classify_flow(struct sk_buff *skb, struct flowi_common *flic)
5261 {
5262 	int rc = call_int_hook(xfrm_decode_session, skb, &flic->flowic_secid,
5263 			       0);
5264 
5265 	BUG_ON(rc);
5266 }
5267 EXPORT_SYMBOL(security_skb_classify_flow);
5268 #endif	/* CONFIG_SECURITY_NETWORK_XFRM */
5269 
5270 #ifdef CONFIG_KEYS
5271 /**
5272  * security_key_alloc() - Allocate and initialize a kernel key LSM blob
5273  * @key: key
5274  * @cred: credentials
5275  * @flags: allocation flags
5276  *
5277  * Permit allocation of a key and assign security data. Note that key does not
5278  * have a serial number assigned at this point.
5279  *
5280  * Return: Return 0 if permission is granted, -ve error otherwise.
5281  */
5282 int security_key_alloc(struct key *key, const struct cred *cred,
5283 		       unsigned long flags)
5284 {
5285 	return call_int_hook(key_alloc, key, cred, flags);
5286 }
5287 
5288 /**
5289  * security_key_free() - Free a kernel key LSM blob
5290  * @key: key
5291  *
5292  * Notification of destruction; free security data.
5293  */
5294 void security_key_free(struct key *key)
5295 {
5296 	call_void_hook(key_free, key);
5297 }
5298 
5299 /**
5300  * security_key_permission() - Check if a kernel key operation is allowed
5301  * @key_ref: key reference
5302  * @cred: credentials of actor requesting access
5303  * @need_perm: requested permissions
5304  *
5305  * See whether a specific operational right is granted to a process on a key.
5306  *
5307  * Return: Return 0 if permission is granted, -ve error otherwise.
5308  */
5309 int security_key_permission(key_ref_t key_ref, const struct cred *cred,
5310 			    enum key_need_perm need_perm)
5311 {
5312 	return call_int_hook(key_permission, key_ref, cred, need_perm);
5313 }
5314 
5315 /**
5316  * security_key_getsecurity() - Get the key's security label
5317  * @key: key
5318  * @buffer: security label buffer
5319  *
5320  * Get a textual representation of the security context attached to a key for
5321  * the purposes of honouring KEYCTL_GETSECURITY.  This function allocates the
5322  * storage for the NUL-terminated string and the caller should free it.
5323  *
5324  * Return: Returns the length of @buffer (including terminating NUL) or -ve if
5325  *         an error occurs.  May also return 0 (and a NULL buffer pointer) if
5326  *         there is no security label assigned to the key.
5327  */
5328 int security_key_getsecurity(struct key *key, char **buffer)
5329 {
5330 	*buffer = NULL;
5331 	return call_int_hook(key_getsecurity, key, buffer);
5332 }
5333 
5334 /**
5335  * security_key_post_create_or_update() - Notification of key create or update
5336  * @keyring: keyring to which the key is linked to
5337  * @key: created or updated key
5338  * @payload: data used to instantiate or update the key
5339  * @payload_len: length of payload
5340  * @flags: key flags
5341  * @create: flag indicating whether the key was created or updated
5342  *
5343  * Notify the caller of a key creation or update.
5344  */
5345 void security_key_post_create_or_update(struct key *keyring, struct key *key,
5346 					const void *payload, size_t payload_len,
5347 					unsigned long flags, bool create)
5348 {
5349 	call_void_hook(key_post_create_or_update, keyring, key, payload,
5350 		       payload_len, flags, create);
5351 }
5352 #endif	/* CONFIG_KEYS */
5353 
5354 #ifdef CONFIG_AUDIT
5355 /**
5356  * security_audit_rule_init() - Allocate and init an LSM audit rule struct
5357  * @field: audit action
5358  * @op: rule operator
5359  * @rulestr: rule context
5360  * @lsmrule: receive buffer for audit rule struct
5361  * @gfp: GFP flag used for kmalloc
5362  *
5363  * Allocate and initialize an LSM audit rule structure.
5364  *
5365  * Return: Return 0 if @lsmrule has been successfully set, -EINVAL in case of
5366  *         an invalid rule.
5367  */
5368 int security_audit_rule_init(u32 field, u32 op, char *rulestr, void **lsmrule,
5369 			     gfp_t gfp)
5370 {
5371 	return call_int_hook(audit_rule_init, field, op, rulestr, lsmrule, gfp);
5372 }
5373 
5374 /**
5375  * security_audit_rule_known() - Check if an audit rule contains LSM fields
5376  * @krule: audit rule
5377  *
5378  * Specifies whether given @krule contains any fields related to the current
5379  * LSM.
5380  *
5381  * Return: Returns 1 in case of relation found, 0 otherwise.
5382  */
5383 int security_audit_rule_known(struct audit_krule *krule)
5384 {
5385 	return call_int_hook(audit_rule_known, krule);
5386 }
5387 
5388 /**
5389  * security_audit_rule_free() - Free an LSM audit rule struct
5390  * @lsmrule: audit rule struct
5391  *
5392  * Deallocate the LSM audit rule structure previously allocated by
5393  * audit_rule_init().
5394  */
5395 void security_audit_rule_free(void *lsmrule)
5396 {
5397 	call_void_hook(audit_rule_free, lsmrule);
5398 }
5399 
5400 /**
5401  * security_audit_rule_match() - Check if a label matches an audit rule
5402  * @secid: security label
5403  * @field: LSM audit field
5404  * @op: matching operator
5405  * @lsmrule: audit rule
5406  *
5407  * Determine if given @secid matches a rule previously approved by
5408  * security_audit_rule_known().
5409  *
5410  * Return: Returns 1 if secid matches the rule, 0 if it does not, -ERRNO on
5411  *         failure.
5412  */
5413 int security_audit_rule_match(u32 secid, u32 field, u32 op, void *lsmrule)
5414 {
5415 	return call_int_hook(audit_rule_match, secid, field, op, lsmrule);
5416 }
5417 #endif /* CONFIG_AUDIT */
5418 
5419 #ifdef CONFIG_BPF_SYSCALL
5420 /**
5421  * security_bpf() - Check if the bpf syscall operation is allowed
5422  * @cmd: command
5423  * @attr: bpf attribute
5424  * @size: size
5425  *
5426  * Do a initial check for all bpf syscalls after the attribute is copied into
5427  * the kernel. The actual security module can implement their own rules to
5428  * check the specific cmd they need.
5429  *
5430  * Return: Returns 0 if permission is granted.
5431  */
5432 int security_bpf(int cmd, union bpf_attr *attr, unsigned int size)
5433 {
5434 	return call_int_hook(bpf, cmd, attr, size);
5435 }
5436 
5437 /**
5438  * security_bpf_map() - Check if access to a bpf map is allowed
5439  * @map: bpf map
5440  * @fmode: mode
5441  *
5442  * Do a check when the kernel generates and returns a file descriptor for eBPF
5443  * maps.
5444  *
5445  * Return: Returns 0 if permission is granted.
5446  */
5447 int security_bpf_map(struct bpf_map *map, fmode_t fmode)
5448 {
5449 	return call_int_hook(bpf_map, map, fmode);
5450 }
5451 
5452 /**
5453  * security_bpf_prog() - Check if access to a bpf program is allowed
5454  * @prog: bpf program
5455  *
5456  * Do a check when the kernel generates and returns a file descriptor for eBPF
5457  * programs.
5458  *
5459  * Return: Returns 0 if permission is granted.
5460  */
5461 int security_bpf_prog(struct bpf_prog *prog)
5462 {
5463 	return call_int_hook(bpf_prog, prog);
5464 }
5465 
5466 /**
5467  * security_bpf_map_create() - Check if BPF map creation is allowed
5468  * @map: BPF map object
5469  * @attr: BPF syscall attributes used to create BPF map
5470  * @token: BPF token used to grant user access
5471  *
5472  * Do a check when the kernel creates a new BPF map. This is also the
5473  * point where LSM blob is allocated for LSMs that need them.
5474  *
5475  * Return: Returns 0 on success, error on failure.
5476  */
5477 int security_bpf_map_create(struct bpf_map *map, union bpf_attr *attr,
5478 			    struct bpf_token *token)
5479 {
5480 	return call_int_hook(bpf_map_create, map, attr, token);
5481 }
5482 
5483 /**
5484  * security_bpf_prog_load() - Check if loading of BPF program is allowed
5485  * @prog: BPF program object
5486  * @attr: BPF syscall attributes used to create BPF program
5487  * @token: BPF token used to grant user access to BPF subsystem
5488  *
5489  * Perform an access control check when the kernel loads a BPF program and
5490  * allocates associated BPF program object. This hook is also responsible for
5491  * allocating any required LSM state for the BPF program.
5492  *
5493  * Return: Returns 0 on success, error on failure.
5494  */
5495 int security_bpf_prog_load(struct bpf_prog *prog, union bpf_attr *attr,
5496 			   struct bpf_token *token)
5497 {
5498 	return call_int_hook(bpf_prog_load, prog, attr, token);
5499 }
5500 
5501 /**
5502  * security_bpf_token_create() - Check if creating of BPF token is allowed
5503  * @token: BPF token object
5504  * @attr: BPF syscall attributes used to create BPF token
5505  * @path: path pointing to BPF FS mount point from which BPF token is created
5506  *
5507  * Do a check when the kernel instantiates a new BPF token object from BPF FS
5508  * instance. This is also the point where LSM blob can be allocated for LSMs.
5509  *
5510  * Return: Returns 0 on success, error on failure.
5511  */
5512 int security_bpf_token_create(struct bpf_token *token, union bpf_attr *attr,
5513 			      struct path *path)
5514 {
5515 	return call_int_hook(bpf_token_create, token, attr, path);
5516 }
5517 
5518 /**
5519  * security_bpf_token_cmd() - Check if BPF token is allowed to delegate
5520  * requested BPF syscall command
5521  * @token: BPF token object
5522  * @cmd: BPF syscall command requested to be delegated by BPF token
5523  *
5524  * Do a check when the kernel decides whether provided BPF token should allow
5525  * delegation of requested BPF syscall command.
5526  *
5527  * Return: Returns 0 on success, error on failure.
5528  */
5529 int security_bpf_token_cmd(const struct bpf_token *token, enum bpf_cmd cmd)
5530 {
5531 	return call_int_hook(bpf_token_cmd, token, cmd);
5532 }
5533 
5534 /**
5535  * security_bpf_token_capable() - Check if BPF token is allowed to delegate
5536  * requested BPF-related capability
5537  * @token: BPF token object
5538  * @cap: capabilities requested to be delegated by BPF token
5539  *
5540  * Do a check when the kernel decides whether provided BPF token should allow
5541  * delegation of requested BPF-related capabilities.
5542  *
5543  * Return: Returns 0 on success, error on failure.
5544  */
5545 int security_bpf_token_capable(const struct bpf_token *token, int cap)
5546 {
5547 	return call_int_hook(bpf_token_capable, token, cap);
5548 }
5549 
5550 /**
5551  * security_bpf_map_free() - Free a bpf map's LSM blob
5552  * @map: bpf map
5553  *
5554  * Clean up the security information stored inside bpf map.
5555  */
5556 void security_bpf_map_free(struct bpf_map *map)
5557 {
5558 	call_void_hook(bpf_map_free, map);
5559 }
5560 
5561 /**
5562  * security_bpf_prog_free() - Free a BPF program's LSM blob
5563  * @prog: BPF program struct
5564  *
5565  * Clean up the security information stored inside BPF program.
5566  */
5567 void security_bpf_prog_free(struct bpf_prog *prog)
5568 {
5569 	call_void_hook(bpf_prog_free, prog);
5570 }
5571 
5572 /**
5573  * security_bpf_token_free() - Free a BPF token's LSM blob
5574  * @token: BPF token struct
5575  *
5576  * Clean up the security information stored inside BPF token.
5577  */
5578 void security_bpf_token_free(struct bpf_token *token)
5579 {
5580 	call_void_hook(bpf_token_free, token);
5581 }
5582 #endif /* CONFIG_BPF_SYSCALL */
5583 
5584 /**
5585  * security_locked_down() - Check if a kernel feature is allowed
5586  * @what: requested kernel feature
5587  *
5588  * Determine whether a kernel feature that potentially enables arbitrary code
5589  * execution in kernel space should be permitted.
5590  *
5591  * Return: Returns 0 if permission is granted.
5592  */
5593 int security_locked_down(enum lockdown_reason what)
5594 {
5595 	return call_int_hook(locked_down, what);
5596 }
5597 EXPORT_SYMBOL(security_locked_down);
5598 
5599 #ifdef CONFIG_PERF_EVENTS
5600 /**
5601  * security_perf_event_open() - Check if a perf event open is allowed
5602  * @attr: perf event attribute
5603  * @type: type of event
5604  *
5605  * Check whether the @type of perf_event_open syscall is allowed.
5606  *
5607  * Return: Returns 0 if permission is granted.
5608  */
5609 int security_perf_event_open(struct perf_event_attr *attr, int type)
5610 {
5611 	return call_int_hook(perf_event_open, attr, type);
5612 }
5613 
5614 /**
5615  * security_perf_event_alloc() - Allocate a perf event LSM blob
5616  * @event: perf event
5617  *
5618  * Allocate and save perf_event security info.
5619  *
5620  * Return: Returns 0 on success, error on failure.
5621  */
5622 int security_perf_event_alloc(struct perf_event *event)
5623 {
5624 	return call_int_hook(perf_event_alloc, event);
5625 }
5626 
5627 /**
5628  * security_perf_event_free() - Free a perf event LSM blob
5629  * @event: perf event
5630  *
5631  * Release (free) perf_event security info.
5632  */
5633 void security_perf_event_free(struct perf_event *event)
5634 {
5635 	call_void_hook(perf_event_free, event);
5636 }
5637 
5638 /**
5639  * security_perf_event_read() - Check if reading a perf event label is allowed
5640  * @event: perf event
5641  *
5642  * Read perf_event security info if allowed.
5643  *
5644  * Return: Returns 0 if permission is granted.
5645  */
5646 int security_perf_event_read(struct perf_event *event)
5647 {
5648 	return call_int_hook(perf_event_read, event);
5649 }
5650 
5651 /**
5652  * security_perf_event_write() - Check if writing a perf event label is allowed
5653  * @event: perf event
5654  *
5655  * Write perf_event security info if allowed.
5656  *
5657  * Return: Returns 0 if permission is granted.
5658  */
5659 int security_perf_event_write(struct perf_event *event)
5660 {
5661 	return call_int_hook(perf_event_write, event);
5662 }
5663 #endif /* CONFIG_PERF_EVENTS */
5664 
5665 #ifdef CONFIG_IO_URING
5666 /**
5667  * security_uring_override_creds() - Check if overriding creds is allowed
5668  * @new: new credentials
5669  *
5670  * Check if the current task, executing an io_uring operation, is allowed to
5671  * override it's credentials with @new.
5672  *
5673  * Return: Returns 0 if permission is granted.
5674  */
5675 int security_uring_override_creds(const struct cred *new)
5676 {
5677 	return call_int_hook(uring_override_creds, new);
5678 }
5679 
5680 /**
5681  * security_uring_sqpoll() - Check if IORING_SETUP_SQPOLL is allowed
5682  *
5683  * Check whether the current task is allowed to spawn a io_uring polling thread
5684  * (IORING_SETUP_SQPOLL).
5685  *
5686  * Return: Returns 0 if permission is granted.
5687  */
5688 int security_uring_sqpoll(void)
5689 {
5690 	return call_int_hook(uring_sqpoll);
5691 }
5692 
5693 /**
5694  * security_uring_cmd() - Check if a io_uring passthrough command is allowed
5695  * @ioucmd: command
5696  *
5697  * Check whether the file_operations uring_cmd is allowed to run.
5698  *
5699  * Return: Returns 0 if permission is granted.
5700  */
5701 int security_uring_cmd(struct io_uring_cmd *ioucmd)
5702 {
5703 	return call_int_hook(uring_cmd, ioucmd);
5704 }
5705 #endif /* CONFIG_IO_URING */
5706