xref: /openbmc/linux/security/security.c (revision 6aeadf78)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Security plug functions
4  *
5  * Copyright (C) 2001 WireX Communications, Inc <chris@wirex.com>
6  * Copyright (C) 2001-2002 Greg Kroah-Hartman <greg@kroah.com>
7  * Copyright (C) 2001 Networks Associates Technology, Inc <ssmalley@nai.com>
8  * Copyright (C) 2016 Mellanox Technologies
9  * Copyright (C) 2023 Microsoft Corporation <paul@paul-moore.com>
10  */
11 
12 #define pr_fmt(fmt) "LSM: " fmt
13 
14 #include <linux/bpf.h>
15 #include <linux/capability.h>
16 #include <linux/dcache.h>
17 #include <linux/export.h>
18 #include <linux/init.h>
19 #include <linux/kernel.h>
20 #include <linux/kernel_read_file.h>
21 #include <linux/lsm_hooks.h>
22 #include <linux/integrity.h>
23 #include <linux/ima.h>
24 #include <linux/evm.h>
25 #include <linux/fsnotify.h>
26 #include <linux/mman.h>
27 #include <linux/mount.h>
28 #include <linux/personality.h>
29 #include <linux/backing-dev.h>
30 #include <linux/string.h>
31 #include <linux/msg.h>
32 #include <net/flow.h>
33 
34 #define MAX_LSM_EVM_XATTR	2
35 
36 /* How many LSMs were built into the kernel? */
37 #define LSM_COUNT (__end_lsm_info - __start_lsm_info)
38 
39 /*
40  * These are descriptions of the reasons that can be passed to the
41  * security_locked_down() LSM hook. Placing this array here allows
42  * all security modules to use the same descriptions for auditing
43  * purposes.
44  */
45 const char *const lockdown_reasons[LOCKDOWN_CONFIDENTIALITY_MAX + 1] = {
46 	[LOCKDOWN_NONE] = "none",
47 	[LOCKDOWN_MODULE_SIGNATURE] = "unsigned module loading",
48 	[LOCKDOWN_DEV_MEM] = "/dev/mem,kmem,port",
49 	[LOCKDOWN_EFI_TEST] = "/dev/efi_test access",
50 	[LOCKDOWN_KEXEC] = "kexec of unsigned images",
51 	[LOCKDOWN_HIBERNATION] = "hibernation",
52 	[LOCKDOWN_PCI_ACCESS] = "direct PCI access",
53 	[LOCKDOWN_IOPORT] = "raw io port access",
54 	[LOCKDOWN_MSR] = "raw MSR access",
55 	[LOCKDOWN_ACPI_TABLES] = "modifying ACPI tables",
56 	[LOCKDOWN_DEVICE_TREE] = "modifying device tree contents",
57 	[LOCKDOWN_PCMCIA_CIS] = "direct PCMCIA CIS storage",
58 	[LOCKDOWN_TIOCSSERIAL] = "reconfiguration of serial port IO",
59 	[LOCKDOWN_MODULE_PARAMETERS] = "unsafe module parameters",
60 	[LOCKDOWN_MMIOTRACE] = "unsafe mmio",
61 	[LOCKDOWN_DEBUGFS] = "debugfs access",
62 	[LOCKDOWN_XMON_WR] = "xmon write access",
63 	[LOCKDOWN_BPF_WRITE_USER] = "use of bpf to write user RAM",
64 	[LOCKDOWN_DBG_WRITE_KERNEL] = "use of kgdb/kdb to write kernel RAM",
65 	[LOCKDOWN_RTAS_ERROR_INJECTION] = "RTAS error injection",
66 	[LOCKDOWN_INTEGRITY_MAX] = "integrity",
67 	[LOCKDOWN_KCORE] = "/proc/kcore access",
68 	[LOCKDOWN_KPROBES] = "use of kprobes",
69 	[LOCKDOWN_BPF_READ_KERNEL] = "use of bpf to read kernel RAM",
70 	[LOCKDOWN_DBG_READ_KERNEL] = "use of kgdb/kdb to read kernel RAM",
71 	[LOCKDOWN_PERF] = "unsafe use of perf",
72 	[LOCKDOWN_TRACEFS] = "use of tracefs",
73 	[LOCKDOWN_XMON_RW] = "xmon read and write access",
74 	[LOCKDOWN_XFRM_SECRET] = "xfrm SA secret",
75 	[LOCKDOWN_CONFIDENTIALITY_MAX] = "confidentiality",
76 };
77 
78 struct security_hook_heads security_hook_heads __ro_after_init;
79 static BLOCKING_NOTIFIER_HEAD(blocking_lsm_notifier_chain);
80 
81 static struct kmem_cache *lsm_file_cache;
82 static struct kmem_cache *lsm_inode_cache;
83 
84 char *lsm_names;
85 static struct lsm_blob_sizes blob_sizes __ro_after_init;
86 
87 /* Boot-time LSM user choice */
88 static __initdata const char *chosen_lsm_order;
89 static __initdata const char *chosen_major_lsm;
90 
91 static __initconst const char *const builtin_lsm_order = CONFIG_LSM;
92 
93 /* Ordered list of LSMs to initialize. */
94 static __initdata struct lsm_info **ordered_lsms;
95 static __initdata struct lsm_info *exclusive;
96 
97 static __initdata bool debug;
98 #define init_debug(...)						\
99 	do {							\
100 		if (debug)					\
101 			pr_info(__VA_ARGS__);			\
102 	} while (0)
103 
104 static bool __init is_enabled(struct lsm_info *lsm)
105 {
106 	if (!lsm->enabled)
107 		return false;
108 
109 	return *lsm->enabled;
110 }
111 
112 /* Mark an LSM's enabled flag. */
113 static int lsm_enabled_true __initdata = 1;
114 static int lsm_enabled_false __initdata = 0;
115 static void __init set_enabled(struct lsm_info *lsm, bool enabled)
116 {
117 	/*
118 	 * When an LSM hasn't configured an enable variable, we can use
119 	 * a hard-coded location for storing the default enabled state.
120 	 */
121 	if (!lsm->enabled) {
122 		if (enabled)
123 			lsm->enabled = &lsm_enabled_true;
124 		else
125 			lsm->enabled = &lsm_enabled_false;
126 	} else if (lsm->enabled == &lsm_enabled_true) {
127 		if (!enabled)
128 			lsm->enabled = &lsm_enabled_false;
129 	} else if (lsm->enabled == &lsm_enabled_false) {
130 		if (enabled)
131 			lsm->enabled = &lsm_enabled_true;
132 	} else {
133 		*lsm->enabled = enabled;
134 	}
135 }
136 
137 /* Is an LSM already listed in the ordered LSMs list? */
138 static bool __init exists_ordered_lsm(struct lsm_info *lsm)
139 {
140 	struct lsm_info **check;
141 
142 	for (check = ordered_lsms; *check; check++)
143 		if (*check == lsm)
144 			return true;
145 
146 	return false;
147 }
148 
149 /* Append an LSM to the list of ordered LSMs to initialize. */
150 static int last_lsm __initdata;
151 static void __init append_ordered_lsm(struct lsm_info *lsm, const char *from)
152 {
153 	/* Ignore duplicate selections. */
154 	if (exists_ordered_lsm(lsm))
155 		return;
156 
157 	if (WARN(last_lsm == LSM_COUNT, "%s: out of LSM slots!?\n", from))
158 		return;
159 
160 	/* Enable this LSM, if it is not already set. */
161 	if (!lsm->enabled)
162 		lsm->enabled = &lsm_enabled_true;
163 	ordered_lsms[last_lsm++] = lsm;
164 
165 	init_debug("%s ordered: %s (%s)\n", from, lsm->name,
166 		   is_enabled(lsm) ? "enabled" : "disabled");
167 }
168 
169 /* Is an LSM allowed to be initialized? */
170 static bool __init lsm_allowed(struct lsm_info *lsm)
171 {
172 	/* Skip if the LSM is disabled. */
173 	if (!is_enabled(lsm))
174 		return false;
175 
176 	/* Not allowed if another exclusive LSM already initialized. */
177 	if ((lsm->flags & LSM_FLAG_EXCLUSIVE) && exclusive) {
178 		init_debug("exclusive disabled: %s\n", lsm->name);
179 		return false;
180 	}
181 
182 	return true;
183 }
184 
185 static void __init lsm_set_blob_size(int *need, int *lbs)
186 {
187 	int offset;
188 
189 	if (*need <= 0)
190 		return;
191 
192 	offset = ALIGN(*lbs, sizeof(void *));
193 	*lbs = offset + *need;
194 	*need = offset;
195 }
196 
197 static void __init lsm_set_blob_sizes(struct lsm_blob_sizes *needed)
198 {
199 	if (!needed)
200 		return;
201 
202 	lsm_set_blob_size(&needed->lbs_cred, &blob_sizes.lbs_cred);
203 	lsm_set_blob_size(&needed->lbs_file, &blob_sizes.lbs_file);
204 	/*
205 	 * The inode blob gets an rcu_head in addition to
206 	 * what the modules might need.
207 	 */
208 	if (needed->lbs_inode && blob_sizes.lbs_inode == 0)
209 		blob_sizes.lbs_inode = sizeof(struct rcu_head);
210 	lsm_set_blob_size(&needed->lbs_inode, &blob_sizes.lbs_inode);
211 	lsm_set_blob_size(&needed->lbs_ipc, &blob_sizes.lbs_ipc);
212 	lsm_set_blob_size(&needed->lbs_msg_msg, &blob_sizes.lbs_msg_msg);
213 	lsm_set_blob_size(&needed->lbs_superblock, &blob_sizes.lbs_superblock);
214 	lsm_set_blob_size(&needed->lbs_task, &blob_sizes.lbs_task);
215 }
216 
217 /* Prepare LSM for initialization. */
218 static void __init prepare_lsm(struct lsm_info *lsm)
219 {
220 	int enabled = lsm_allowed(lsm);
221 
222 	/* Record enablement (to handle any following exclusive LSMs). */
223 	set_enabled(lsm, enabled);
224 
225 	/* If enabled, do pre-initialization work. */
226 	if (enabled) {
227 		if ((lsm->flags & LSM_FLAG_EXCLUSIVE) && !exclusive) {
228 			exclusive = lsm;
229 			init_debug("exclusive chosen:   %s\n", lsm->name);
230 		}
231 
232 		lsm_set_blob_sizes(lsm->blobs);
233 	}
234 }
235 
236 /* Initialize a given LSM, if it is enabled. */
237 static void __init initialize_lsm(struct lsm_info *lsm)
238 {
239 	if (is_enabled(lsm)) {
240 		int ret;
241 
242 		init_debug("initializing %s\n", lsm->name);
243 		ret = lsm->init();
244 		WARN(ret, "%s failed to initialize: %d\n", lsm->name, ret);
245 	}
246 }
247 
248 /* Populate ordered LSMs list from comma-separated LSM name list. */
249 static void __init ordered_lsm_parse(const char *order, const char *origin)
250 {
251 	struct lsm_info *lsm;
252 	char *sep, *name, *next;
253 
254 	/* LSM_ORDER_FIRST is always first. */
255 	for (lsm = __start_lsm_info; lsm < __end_lsm_info; lsm++) {
256 		if (lsm->order == LSM_ORDER_FIRST)
257 			append_ordered_lsm(lsm, "  first");
258 	}
259 
260 	/* Process "security=", if given. */
261 	if (chosen_major_lsm) {
262 		struct lsm_info *major;
263 
264 		/*
265 		 * To match the original "security=" behavior, this
266 		 * explicitly does NOT fallback to another Legacy Major
267 		 * if the selected one was separately disabled: disable
268 		 * all non-matching Legacy Major LSMs.
269 		 */
270 		for (major = __start_lsm_info; major < __end_lsm_info;
271 		     major++) {
272 			if ((major->flags & LSM_FLAG_LEGACY_MAJOR) &&
273 			    strcmp(major->name, chosen_major_lsm) != 0) {
274 				set_enabled(major, false);
275 				init_debug("security=%s disabled: %s (only one legacy major LSM)\n",
276 					   chosen_major_lsm, major->name);
277 			}
278 		}
279 	}
280 
281 	sep = kstrdup(order, GFP_KERNEL);
282 	next = sep;
283 	/* Walk the list, looking for matching LSMs. */
284 	while ((name = strsep(&next, ",")) != NULL) {
285 		bool found = false;
286 
287 		for (lsm = __start_lsm_info; lsm < __end_lsm_info; lsm++) {
288 			if (strcmp(lsm->name, name) == 0) {
289 				if (lsm->order == LSM_ORDER_MUTABLE)
290 					append_ordered_lsm(lsm, origin);
291 				found = true;
292 			}
293 		}
294 
295 		if (!found)
296 			init_debug("%s ignored: %s (not built into kernel)\n",
297 				   origin, name);
298 	}
299 
300 	/* Process "security=", if given. */
301 	if (chosen_major_lsm) {
302 		for (lsm = __start_lsm_info; lsm < __end_lsm_info; lsm++) {
303 			if (exists_ordered_lsm(lsm))
304 				continue;
305 			if (strcmp(lsm->name, chosen_major_lsm) == 0)
306 				append_ordered_lsm(lsm, "security=");
307 		}
308 	}
309 
310 	/* LSM_ORDER_LAST is always last. */
311 	for (lsm = __start_lsm_info; lsm < __end_lsm_info; lsm++) {
312 		if (lsm->order == LSM_ORDER_LAST)
313 			append_ordered_lsm(lsm, "   last");
314 	}
315 
316 	/* Disable all LSMs not in the ordered list. */
317 	for (lsm = __start_lsm_info; lsm < __end_lsm_info; lsm++) {
318 		if (exists_ordered_lsm(lsm))
319 			continue;
320 		set_enabled(lsm, false);
321 		init_debug("%s skipped: %s (not in requested order)\n",
322 			   origin, lsm->name);
323 	}
324 
325 	kfree(sep);
326 }
327 
328 static void __init lsm_early_cred(struct cred *cred);
329 static void __init lsm_early_task(struct task_struct *task);
330 
331 static int lsm_append(const char *new, char **result);
332 
333 static void __init report_lsm_order(void)
334 {
335 	struct lsm_info **lsm, *early;
336 	int first = 0;
337 
338 	pr_info("initializing lsm=");
339 
340 	/* Report each enabled LSM name, comma separated. */
341 	for (early = __start_early_lsm_info;
342 	     early < __end_early_lsm_info; early++)
343 		if (is_enabled(early))
344 			pr_cont("%s%s", first++ == 0 ? "" : ",", early->name);
345 	for (lsm = ordered_lsms; *lsm; lsm++)
346 		if (is_enabled(*lsm))
347 			pr_cont("%s%s", first++ == 0 ? "" : ",", (*lsm)->name);
348 
349 	pr_cont("\n");
350 }
351 
352 static void __init ordered_lsm_init(void)
353 {
354 	struct lsm_info **lsm;
355 
356 	ordered_lsms = kcalloc(LSM_COUNT + 1, sizeof(*ordered_lsms),
357 			       GFP_KERNEL);
358 
359 	if (chosen_lsm_order) {
360 		if (chosen_major_lsm) {
361 			pr_warn("security=%s is ignored because it is superseded by lsm=%s\n",
362 				chosen_major_lsm, chosen_lsm_order);
363 			chosen_major_lsm = NULL;
364 		}
365 		ordered_lsm_parse(chosen_lsm_order, "cmdline");
366 	} else
367 		ordered_lsm_parse(builtin_lsm_order, "builtin");
368 
369 	for (lsm = ordered_lsms; *lsm; lsm++)
370 		prepare_lsm(*lsm);
371 
372 	report_lsm_order();
373 
374 	init_debug("cred blob size       = %d\n", blob_sizes.lbs_cred);
375 	init_debug("file blob size       = %d\n", blob_sizes.lbs_file);
376 	init_debug("inode blob size      = %d\n", blob_sizes.lbs_inode);
377 	init_debug("ipc blob size        = %d\n", blob_sizes.lbs_ipc);
378 	init_debug("msg_msg blob size    = %d\n", blob_sizes.lbs_msg_msg);
379 	init_debug("superblock blob size = %d\n", blob_sizes.lbs_superblock);
380 	init_debug("task blob size       = %d\n", blob_sizes.lbs_task);
381 
382 	/*
383 	 * Create any kmem_caches needed for blobs
384 	 */
385 	if (blob_sizes.lbs_file)
386 		lsm_file_cache = kmem_cache_create("lsm_file_cache",
387 						   blob_sizes.lbs_file, 0,
388 						   SLAB_PANIC, NULL);
389 	if (blob_sizes.lbs_inode)
390 		lsm_inode_cache = kmem_cache_create("lsm_inode_cache",
391 						    blob_sizes.lbs_inode, 0,
392 						    SLAB_PANIC, NULL);
393 
394 	lsm_early_cred((struct cred *) current->cred);
395 	lsm_early_task(current);
396 	for (lsm = ordered_lsms; *lsm; lsm++)
397 		initialize_lsm(*lsm);
398 
399 	kfree(ordered_lsms);
400 }
401 
402 int __init early_security_init(void)
403 {
404 	struct lsm_info *lsm;
405 
406 #define LSM_HOOK(RET, DEFAULT, NAME, ...) \
407 	INIT_HLIST_HEAD(&security_hook_heads.NAME);
408 #include "linux/lsm_hook_defs.h"
409 #undef LSM_HOOK
410 
411 	for (lsm = __start_early_lsm_info; lsm < __end_early_lsm_info; lsm++) {
412 		if (!lsm->enabled)
413 			lsm->enabled = &lsm_enabled_true;
414 		prepare_lsm(lsm);
415 		initialize_lsm(lsm);
416 	}
417 
418 	return 0;
419 }
420 
421 /**
422  * security_init - initializes the security framework
423  *
424  * This should be called early in the kernel initialization sequence.
425  */
426 int __init security_init(void)
427 {
428 	struct lsm_info *lsm;
429 
430 	init_debug("legacy security=%s\n", chosen_major_lsm ? : " *unspecified*");
431 	init_debug("  CONFIG_LSM=%s\n", builtin_lsm_order);
432 	init_debug("boot arg lsm=%s\n", chosen_lsm_order ? : " *unspecified*");
433 
434 	/*
435 	 * Append the names of the early LSM modules now that kmalloc() is
436 	 * available
437 	 */
438 	for (lsm = __start_early_lsm_info; lsm < __end_early_lsm_info; lsm++) {
439 		init_debug("  early started: %s (%s)\n", lsm->name,
440 			   is_enabled(lsm) ? "enabled" : "disabled");
441 		if (lsm->enabled)
442 			lsm_append(lsm->name, &lsm_names);
443 	}
444 
445 	/* Load LSMs in specified order. */
446 	ordered_lsm_init();
447 
448 	return 0;
449 }
450 
451 /* Save user chosen LSM */
452 static int __init choose_major_lsm(char *str)
453 {
454 	chosen_major_lsm = str;
455 	return 1;
456 }
457 __setup("security=", choose_major_lsm);
458 
459 /* Explicitly choose LSM initialization order. */
460 static int __init choose_lsm_order(char *str)
461 {
462 	chosen_lsm_order = str;
463 	return 1;
464 }
465 __setup("lsm=", choose_lsm_order);
466 
467 /* Enable LSM order debugging. */
468 static int __init enable_debug(char *str)
469 {
470 	debug = true;
471 	return 1;
472 }
473 __setup("lsm.debug", enable_debug);
474 
475 static bool match_last_lsm(const char *list, const char *lsm)
476 {
477 	const char *last;
478 
479 	if (WARN_ON(!list || !lsm))
480 		return false;
481 	last = strrchr(list, ',');
482 	if (last)
483 		/* Pass the comma, strcmp() will check for '\0' */
484 		last++;
485 	else
486 		last = list;
487 	return !strcmp(last, lsm);
488 }
489 
490 static int lsm_append(const char *new, char **result)
491 {
492 	char *cp;
493 
494 	if (*result == NULL) {
495 		*result = kstrdup(new, GFP_KERNEL);
496 		if (*result == NULL)
497 			return -ENOMEM;
498 	} else {
499 		/* Check if it is the last registered name */
500 		if (match_last_lsm(*result, new))
501 			return 0;
502 		cp = kasprintf(GFP_KERNEL, "%s,%s", *result, new);
503 		if (cp == NULL)
504 			return -ENOMEM;
505 		kfree(*result);
506 		*result = cp;
507 	}
508 	return 0;
509 }
510 
511 /**
512  * security_add_hooks - Add a modules hooks to the hook lists.
513  * @hooks: the hooks to add
514  * @count: the number of hooks to add
515  * @lsm: the name of the security module
516  *
517  * Each LSM has to register its hooks with the infrastructure.
518  */
519 void __init security_add_hooks(struct security_hook_list *hooks, int count,
520 			       const char *lsm)
521 {
522 	int i;
523 
524 	for (i = 0; i < count; i++) {
525 		hooks[i].lsm = lsm;
526 		hlist_add_tail_rcu(&hooks[i].list, hooks[i].head);
527 	}
528 
529 	/*
530 	 * Don't try to append during early_security_init(), we'll come back
531 	 * and fix this up afterwards.
532 	 */
533 	if (slab_is_available()) {
534 		if (lsm_append(lsm, &lsm_names) < 0)
535 			panic("%s - Cannot get early memory.\n", __func__);
536 	}
537 }
538 
539 int call_blocking_lsm_notifier(enum lsm_event event, void *data)
540 {
541 	return blocking_notifier_call_chain(&blocking_lsm_notifier_chain,
542 					    event, data);
543 }
544 EXPORT_SYMBOL(call_blocking_lsm_notifier);
545 
546 int register_blocking_lsm_notifier(struct notifier_block *nb)
547 {
548 	return blocking_notifier_chain_register(&blocking_lsm_notifier_chain,
549 						nb);
550 }
551 EXPORT_SYMBOL(register_blocking_lsm_notifier);
552 
553 int unregister_blocking_lsm_notifier(struct notifier_block *nb)
554 {
555 	return blocking_notifier_chain_unregister(&blocking_lsm_notifier_chain,
556 						  nb);
557 }
558 EXPORT_SYMBOL(unregister_blocking_lsm_notifier);
559 
560 /**
561  * lsm_cred_alloc - allocate a composite cred blob
562  * @cred: the cred that needs a blob
563  * @gfp: allocation type
564  *
565  * Allocate the cred blob for all the modules
566  *
567  * Returns 0, or -ENOMEM if memory can't be allocated.
568  */
569 static int lsm_cred_alloc(struct cred *cred, gfp_t gfp)
570 {
571 	if (blob_sizes.lbs_cred == 0) {
572 		cred->security = NULL;
573 		return 0;
574 	}
575 
576 	cred->security = kzalloc(blob_sizes.lbs_cred, gfp);
577 	if (cred->security == NULL)
578 		return -ENOMEM;
579 	return 0;
580 }
581 
582 /**
583  * lsm_early_cred - during initialization allocate a composite cred blob
584  * @cred: the cred that needs a blob
585  *
586  * Allocate the cred blob for all the modules
587  */
588 static void __init lsm_early_cred(struct cred *cred)
589 {
590 	int rc = lsm_cred_alloc(cred, GFP_KERNEL);
591 
592 	if (rc)
593 		panic("%s: Early cred alloc failed.\n", __func__);
594 }
595 
596 /**
597  * lsm_file_alloc - allocate a composite file blob
598  * @file: the file that needs a blob
599  *
600  * Allocate the file blob for all the modules
601  *
602  * Returns 0, or -ENOMEM if memory can't be allocated.
603  */
604 static int lsm_file_alloc(struct file *file)
605 {
606 	if (!lsm_file_cache) {
607 		file->f_security = NULL;
608 		return 0;
609 	}
610 
611 	file->f_security = kmem_cache_zalloc(lsm_file_cache, GFP_KERNEL);
612 	if (file->f_security == NULL)
613 		return -ENOMEM;
614 	return 0;
615 }
616 
617 /**
618  * lsm_inode_alloc - allocate a composite inode blob
619  * @inode: the inode that needs a blob
620  *
621  * Allocate the inode blob for all the modules
622  *
623  * Returns 0, or -ENOMEM if memory can't be allocated.
624  */
625 int lsm_inode_alloc(struct inode *inode)
626 {
627 	if (!lsm_inode_cache) {
628 		inode->i_security = NULL;
629 		return 0;
630 	}
631 
632 	inode->i_security = kmem_cache_zalloc(lsm_inode_cache, GFP_NOFS);
633 	if (inode->i_security == NULL)
634 		return -ENOMEM;
635 	return 0;
636 }
637 
638 /**
639  * lsm_task_alloc - allocate a composite task blob
640  * @task: the task that needs a blob
641  *
642  * Allocate the task blob for all the modules
643  *
644  * Returns 0, or -ENOMEM if memory can't be allocated.
645  */
646 static int lsm_task_alloc(struct task_struct *task)
647 {
648 	if (blob_sizes.lbs_task == 0) {
649 		task->security = NULL;
650 		return 0;
651 	}
652 
653 	task->security = kzalloc(blob_sizes.lbs_task, GFP_KERNEL);
654 	if (task->security == NULL)
655 		return -ENOMEM;
656 	return 0;
657 }
658 
659 /**
660  * lsm_ipc_alloc - allocate a composite ipc blob
661  * @kip: the ipc that needs a blob
662  *
663  * Allocate the ipc blob for all the modules
664  *
665  * Returns 0, or -ENOMEM if memory can't be allocated.
666  */
667 static int lsm_ipc_alloc(struct kern_ipc_perm *kip)
668 {
669 	if (blob_sizes.lbs_ipc == 0) {
670 		kip->security = NULL;
671 		return 0;
672 	}
673 
674 	kip->security = kzalloc(blob_sizes.lbs_ipc, GFP_KERNEL);
675 	if (kip->security == NULL)
676 		return -ENOMEM;
677 	return 0;
678 }
679 
680 /**
681  * lsm_msg_msg_alloc - allocate a composite msg_msg blob
682  * @mp: the msg_msg that needs a blob
683  *
684  * Allocate the ipc blob for all the modules
685  *
686  * Returns 0, or -ENOMEM if memory can't be allocated.
687  */
688 static int lsm_msg_msg_alloc(struct msg_msg *mp)
689 {
690 	if (blob_sizes.lbs_msg_msg == 0) {
691 		mp->security = NULL;
692 		return 0;
693 	}
694 
695 	mp->security = kzalloc(blob_sizes.lbs_msg_msg, GFP_KERNEL);
696 	if (mp->security == NULL)
697 		return -ENOMEM;
698 	return 0;
699 }
700 
701 /**
702  * lsm_early_task - during initialization allocate a composite task blob
703  * @task: the task that needs a blob
704  *
705  * Allocate the task blob for all the modules
706  */
707 static void __init lsm_early_task(struct task_struct *task)
708 {
709 	int rc = lsm_task_alloc(task);
710 
711 	if (rc)
712 		panic("%s: Early task alloc failed.\n", __func__);
713 }
714 
715 /**
716  * lsm_superblock_alloc - allocate a composite superblock blob
717  * @sb: the superblock that needs a blob
718  *
719  * Allocate the superblock blob for all the modules
720  *
721  * Returns 0, or -ENOMEM if memory can't be allocated.
722  */
723 static int lsm_superblock_alloc(struct super_block *sb)
724 {
725 	if (blob_sizes.lbs_superblock == 0) {
726 		sb->s_security = NULL;
727 		return 0;
728 	}
729 
730 	sb->s_security = kzalloc(blob_sizes.lbs_superblock, GFP_KERNEL);
731 	if (sb->s_security == NULL)
732 		return -ENOMEM;
733 	return 0;
734 }
735 
736 /*
737  * The default value of the LSM hook is defined in linux/lsm_hook_defs.h and
738  * can be accessed with:
739  *
740  *	LSM_RET_DEFAULT(<hook_name>)
741  *
742  * The macros below define static constants for the default value of each
743  * LSM hook.
744  */
745 #define LSM_RET_DEFAULT(NAME) (NAME##_default)
746 #define DECLARE_LSM_RET_DEFAULT_void(DEFAULT, NAME)
747 #define DECLARE_LSM_RET_DEFAULT_int(DEFAULT, NAME) \
748 	static const int __maybe_unused LSM_RET_DEFAULT(NAME) = (DEFAULT);
749 #define LSM_HOOK(RET, DEFAULT, NAME, ...) \
750 	DECLARE_LSM_RET_DEFAULT_##RET(DEFAULT, NAME)
751 
752 #include <linux/lsm_hook_defs.h>
753 #undef LSM_HOOK
754 
755 /*
756  * Hook list operation macros.
757  *
758  * call_void_hook:
759  *	This is a hook that does not return a value.
760  *
761  * call_int_hook:
762  *	This is a hook that returns a value.
763  */
764 
765 #define call_void_hook(FUNC, ...)				\
766 	do {							\
767 		struct security_hook_list *P;			\
768 								\
769 		hlist_for_each_entry(P, &security_hook_heads.FUNC, list) \
770 			P->hook.FUNC(__VA_ARGS__);		\
771 	} while (0)
772 
773 #define call_int_hook(FUNC, IRC, ...) ({			\
774 	int RC = IRC;						\
775 	do {							\
776 		struct security_hook_list *P;			\
777 								\
778 		hlist_for_each_entry(P, &security_hook_heads.FUNC, list) { \
779 			RC = P->hook.FUNC(__VA_ARGS__);		\
780 			if (RC != 0)				\
781 				break;				\
782 		}						\
783 	} while (0);						\
784 	RC;							\
785 })
786 
787 /* Security operations */
788 
789 /**
790  * security_binder_set_context_mgr() - Check if becoming binder ctx mgr is ok
791  * @mgr: task credentials of current binder process
792  *
793  * Check whether @mgr is allowed to be the binder context manager.
794  *
795  * Return: Return 0 if permission is granted.
796  */
797 int security_binder_set_context_mgr(const struct cred *mgr)
798 {
799 	return call_int_hook(binder_set_context_mgr, 0, mgr);
800 }
801 
802 /**
803  * security_binder_transaction() - Check if a binder transaction is allowed
804  * @from: sending process
805  * @to: receiving process
806  *
807  * Check whether @from is allowed to invoke a binder transaction call to @to.
808  *
809  * Return: Returns 0 if permission is granted.
810  */
811 int security_binder_transaction(const struct cred *from,
812 				const struct cred *to)
813 {
814 	return call_int_hook(binder_transaction, 0, from, to);
815 }
816 
817 /**
818  * security_binder_transfer_binder() - Check if a binder transfer is allowed
819  * @from: sending process
820  * @to: receiving process
821  *
822  * Check whether @from is allowed to transfer a binder reference to @to.
823  *
824  * Return: Returns 0 if permission is granted.
825  */
826 int security_binder_transfer_binder(const struct cred *from,
827 				    const struct cred *to)
828 {
829 	return call_int_hook(binder_transfer_binder, 0, from, to);
830 }
831 
832 /**
833  * security_binder_transfer_file() - Check if a binder file xfer is allowed
834  * @from: sending process
835  * @to: receiving process
836  * @file: file being transferred
837  *
838  * Check whether @from is allowed to transfer @file to @to.
839  *
840  * Return: Returns 0 if permission is granted.
841  */
842 int security_binder_transfer_file(const struct cred *from,
843 				  const struct cred *to, struct file *file)
844 {
845 	return call_int_hook(binder_transfer_file, 0, from, to, file);
846 }
847 
848 /**
849  * security_ptrace_access_check() - Check if tracing is allowed
850  * @child: target process
851  * @mode: PTRACE_MODE flags
852  *
853  * Check permission before allowing the current process to trace the @child
854  * process.  Security modules may also want to perform a process tracing check
855  * during an execve in the set_security or apply_creds hooks of tracing check
856  * during an execve in the bprm_set_creds hook of binprm_security_ops if the
857  * process is being traced and its security attributes would be changed by the
858  * execve.
859  *
860  * Return: Returns 0 if permission is granted.
861  */
862 int security_ptrace_access_check(struct task_struct *child, unsigned int mode)
863 {
864 	return call_int_hook(ptrace_access_check, 0, child, mode);
865 }
866 
867 /**
868  * security_ptrace_traceme() - Check if tracing is allowed
869  * @parent: tracing process
870  *
871  * Check that the @parent process has sufficient permission to trace the
872  * current process before allowing the current process to present itself to the
873  * @parent process for tracing.
874  *
875  * Return: Returns 0 if permission is granted.
876  */
877 int security_ptrace_traceme(struct task_struct *parent)
878 {
879 	return call_int_hook(ptrace_traceme, 0, parent);
880 }
881 
882 /**
883  * security_capget() - Get the capability sets for a process
884  * @target: target process
885  * @effective: effective capability set
886  * @inheritable: inheritable capability set
887  * @permitted: permitted capability set
888  *
889  * Get the @effective, @inheritable, and @permitted capability sets for the
890  * @target process.  The hook may also perform permission checking to determine
891  * if the current process is allowed to see the capability sets of the @target
892  * process.
893  *
894  * Return: Returns 0 if the capability sets were successfully obtained.
895  */
896 int security_capget(struct task_struct *target,
897 		    kernel_cap_t *effective,
898 		    kernel_cap_t *inheritable,
899 		    kernel_cap_t *permitted)
900 {
901 	return call_int_hook(capget, 0, target,
902 			     effective, inheritable, permitted);
903 }
904 
905 /**
906  * security_capset() - Set the capability sets for a process
907  * @new: new credentials for the target process
908  * @old: current credentials of the target process
909  * @effective: effective capability set
910  * @inheritable: inheritable capability set
911  * @permitted: permitted capability set
912  *
913  * Set the @effective, @inheritable, and @permitted capability sets for the
914  * current process.
915  *
916  * Return: Returns 0 and update @new if permission is granted.
917  */
918 int security_capset(struct cred *new, const struct cred *old,
919 		    const kernel_cap_t *effective,
920 		    const kernel_cap_t *inheritable,
921 		    const kernel_cap_t *permitted)
922 {
923 	return call_int_hook(capset, 0, new, old,
924 			     effective, inheritable, permitted);
925 }
926 
927 /**
928  * security_capable() - Check if a process has the necessary capability
929  * @cred: credentials to examine
930  * @ns: user namespace
931  * @cap: capability requested
932  * @opts: capability check options
933  *
934  * Check whether the @tsk process has the @cap capability in the indicated
935  * credentials.  @cap contains the capability <include/linux/capability.h>.
936  * @opts contains options for the capable check <include/linux/security.h>.
937  *
938  * Return: Returns 0 if the capability is granted.
939  */
940 int security_capable(const struct cred *cred,
941 		     struct user_namespace *ns,
942 		     int cap,
943 		     unsigned int opts)
944 {
945 	return call_int_hook(capable, 0, cred, ns, cap, opts);
946 }
947 
948 /**
949  * security_quotactl() - Check if a quotactl() syscall is allowed for this fs
950  * @cmds: commands
951  * @type: type
952  * @id: id
953  * @sb: filesystem
954  *
955  * Check whether the quotactl syscall is allowed for this @sb.
956  *
957  * Return: Returns 0 if permission is granted.
958  */
959 int security_quotactl(int cmds, int type, int id, struct super_block *sb)
960 {
961 	return call_int_hook(quotactl, 0, cmds, type, id, sb);
962 }
963 
964 /**
965  * security_quota_on() - Check if QUOTAON is allowed for a dentry
966  * @dentry: dentry
967  *
968  * Check whether QUOTAON is allowed for @dentry.
969  *
970  * Return: Returns 0 if permission is granted.
971  */
972 int security_quota_on(struct dentry *dentry)
973 {
974 	return call_int_hook(quota_on, 0, dentry);
975 }
976 
977 /**
978  * security_syslog() - Check if accessing the kernel message ring is allowed
979  * @type: SYSLOG_ACTION_* type
980  *
981  * Check permission before accessing the kernel message ring or changing
982  * logging to the console.  See the syslog(2) manual page for an explanation of
983  * the @type values.
984  *
985  * Return: Return 0 if permission is granted.
986  */
987 int security_syslog(int type)
988 {
989 	return call_int_hook(syslog, 0, type);
990 }
991 
992 /**
993  * security_settime64() - Check if changing the system time is allowed
994  * @ts: new time
995  * @tz: timezone
996  *
997  * Check permission to change the system time, struct timespec64 is defined in
998  * <include/linux/time64.h> and timezone is defined in <include/linux/time.h>.
999  *
1000  * Return: Returns 0 if permission is granted.
1001  */
1002 int security_settime64(const struct timespec64 *ts, const struct timezone *tz)
1003 {
1004 	return call_int_hook(settime, 0, ts, tz);
1005 }
1006 
1007 /**
1008  * security_vm_enough_memory_mm() - Check if allocating a new mem map is allowed
1009  * @mm: mm struct
1010  * @pages: number of pages
1011  *
1012  * Check permissions for allocating a new virtual mapping.  If all LSMs return
1013  * a positive value, __vm_enough_memory() will be called with cap_sys_admin
1014  * set. If at least one LSM returns 0 or negative, __vm_enough_memory() will be
1015  * called with cap_sys_admin cleared.
1016  *
1017  * Return: Returns 0 if permission is granted by the LSM infrastructure to the
1018  *         caller.
1019  */
1020 int security_vm_enough_memory_mm(struct mm_struct *mm, long pages)
1021 {
1022 	struct security_hook_list *hp;
1023 	int cap_sys_admin = 1;
1024 	int rc;
1025 
1026 	/*
1027 	 * The module will respond with a positive value if
1028 	 * it thinks the __vm_enough_memory() call should be
1029 	 * made with the cap_sys_admin set. If all of the modules
1030 	 * agree that it should be set it will. If any module
1031 	 * thinks it should not be set it won't.
1032 	 */
1033 	hlist_for_each_entry(hp, &security_hook_heads.vm_enough_memory, list) {
1034 		rc = hp->hook.vm_enough_memory(mm, pages);
1035 		if (rc <= 0) {
1036 			cap_sys_admin = 0;
1037 			break;
1038 		}
1039 	}
1040 	return __vm_enough_memory(mm, pages, cap_sys_admin);
1041 }
1042 
1043 /**
1044  * security_bprm_creds_for_exec() - Prepare the credentials for exec()
1045  * @bprm: binary program information
1046  *
1047  * If the setup in prepare_exec_creds did not setup @bprm->cred->security
1048  * properly for executing @bprm->file, update the LSM's portion of
1049  * @bprm->cred->security to be what commit_creds needs to install for the new
1050  * program.  This hook may also optionally check permissions (e.g. for
1051  * transitions between security domains).  The hook must set @bprm->secureexec
1052  * to 1 if AT_SECURE should be set to request libc enable secure mode.  @bprm
1053  * contains the linux_binprm structure.
1054  *
1055  * Return: Returns 0 if the hook is successful and permission is granted.
1056  */
1057 int security_bprm_creds_for_exec(struct linux_binprm *bprm)
1058 {
1059 	return call_int_hook(bprm_creds_for_exec, 0, bprm);
1060 }
1061 
1062 /**
1063  * security_bprm_creds_from_file() - Update linux_binprm creds based on file
1064  * @bprm: binary program information
1065  * @file: associated file
1066  *
1067  * If @file is setpcap, suid, sgid or otherwise marked to change privilege upon
1068  * exec, update @bprm->cred to reflect that change. This is called after
1069  * finding the binary that will be executed without an interpreter.  This
1070  * ensures that the credentials will not be derived from a script that the
1071  * binary will need to reopen, which when reopend may end up being a completely
1072  * different file.  This hook may also optionally check permissions (e.g. for
1073  * transitions between security domains).  The hook must set @bprm->secureexec
1074  * to 1 if AT_SECURE should be set to request libc enable secure mode.  The
1075  * hook must add to @bprm->per_clear any personality flags that should be
1076  * cleared from current->personality.  @bprm contains the linux_binprm
1077  * structure.
1078  *
1079  * Return: Returns 0 if the hook is successful and permission is granted.
1080  */
1081 int security_bprm_creds_from_file(struct linux_binprm *bprm, struct file *file)
1082 {
1083 	return call_int_hook(bprm_creds_from_file, 0, bprm, file);
1084 }
1085 
1086 /**
1087  * security_bprm_check() - Mediate binary handler search
1088  * @bprm: binary program information
1089  *
1090  * This hook mediates the point when a search for a binary handler will begin.
1091  * It allows a check against the @bprm->cred->security value which was set in
1092  * the preceding creds_for_exec call.  The argv list and envp list are reliably
1093  * available in @bprm.  This hook may be called multiple times during a single
1094  * execve.  @bprm contains the linux_binprm structure.
1095  *
1096  * Return: Returns 0 if the hook is successful and permission is granted.
1097  */
1098 int security_bprm_check(struct linux_binprm *bprm)
1099 {
1100 	int ret;
1101 
1102 	ret = call_int_hook(bprm_check_security, 0, bprm);
1103 	if (ret)
1104 		return ret;
1105 	return ima_bprm_check(bprm);
1106 }
1107 
1108 /**
1109  * security_bprm_committing_creds() - Install creds for a process during exec()
1110  * @bprm: binary program information
1111  *
1112  * Prepare to install the new security attributes of a process being
1113  * transformed by an execve operation, based on the old credentials pointed to
1114  * by @current->cred and the information set in @bprm->cred by the
1115  * bprm_creds_for_exec hook.  @bprm points to the linux_binprm structure.  This
1116  * hook is a good place to perform state changes on the process such as closing
1117  * open file descriptors to which access will no longer be granted when the
1118  * attributes are changed.  This is called immediately before commit_creds().
1119  */
1120 void security_bprm_committing_creds(struct linux_binprm *bprm)
1121 {
1122 	call_void_hook(bprm_committing_creds, bprm);
1123 }
1124 
1125 /**
1126  * security_bprm_committed_creds() - Tidy up after cred install during exec()
1127  * @bprm: binary program information
1128  *
1129  * Tidy up after the installation of the new security attributes of a process
1130  * being transformed by an execve operation.  The new credentials have, by this
1131  * point, been set to @current->cred.  @bprm points to the linux_binprm
1132  * structure.  This hook is a good place to perform state changes on the
1133  * process such as clearing out non-inheritable signal state.  This is called
1134  * immediately after commit_creds().
1135  */
1136 void security_bprm_committed_creds(struct linux_binprm *bprm)
1137 {
1138 	call_void_hook(bprm_committed_creds, bprm);
1139 }
1140 
1141 /**
1142  * security_fs_context_dup() - Duplicate a fs_context LSM blob
1143  * @fc: destination filesystem context
1144  * @src_fc: source filesystem context
1145  *
1146  * Allocate and attach a security structure to sc->security.  This pointer is
1147  * initialised to NULL by the caller.  @fc indicates the new filesystem context.
1148  * @src_fc indicates the original filesystem context.
1149  *
1150  * Return: Returns 0 on success or a negative error code on failure.
1151  */
1152 int security_fs_context_dup(struct fs_context *fc, struct fs_context *src_fc)
1153 {
1154 	return call_int_hook(fs_context_dup, 0, fc, src_fc);
1155 }
1156 
1157 /**
1158  * security_fs_context_parse_param() - Configure a filesystem context
1159  * @fc: filesystem context
1160  * @param: filesystem parameter
1161  *
1162  * Userspace provided a parameter to configure a superblock.  The LSM can
1163  * consume the parameter or return it to the caller for use elsewhere.
1164  *
1165  * Return: If the parameter is used by the LSM it should return 0, if it is
1166  *         returned to the caller -ENOPARAM is returned, otherwise a negative
1167  *         error code is returned.
1168  */
1169 int security_fs_context_parse_param(struct fs_context *fc,
1170 				    struct fs_parameter *param)
1171 {
1172 	struct security_hook_list *hp;
1173 	int trc;
1174 	int rc = -ENOPARAM;
1175 
1176 	hlist_for_each_entry(hp, &security_hook_heads.fs_context_parse_param,
1177 			     list) {
1178 		trc = hp->hook.fs_context_parse_param(fc, param);
1179 		if (trc == 0)
1180 			rc = 0;
1181 		else if (trc != -ENOPARAM)
1182 			return trc;
1183 	}
1184 	return rc;
1185 }
1186 
1187 /**
1188  * security_sb_alloc() - Allocate a super_block LSM blob
1189  * @sb: filesystem superblock
1190  *
1191  * Allocate and attach a security structure to the sb->s_security field.  The
1192  * s_security field is initialized to NULL when the structure is allocated.
1193  * @sb contains the super_block structure to be modified.
1194  *
1195  * Return: Returns 0 if operation was successful.
1196  */
1197 int security_sb_alloc(struct super_block *sb)
1198 {
1199 	int rc = lsm_superblock_alloc(sb);
1200 
1201 	if (unlikely(rc))
1202 		return rc;
1203 	rc = call_int_hook(sb_alloc_security, 0, sb);
1204 	if (unlikely(rc))
1205 		security_sb_free(sb);
1206 	return rc;
1207 }
1208 
1209 /**
1210  * security_sb_delete() - Release super_block LSM associated objects
1211  * @sb: filesystem superblock
1212  *
1213  * Release objects tied to a superblock (e.g. inodes).  @sb contains the
1214  * super_block structure being released.
1215  */
1216 void security_sb_delete(struct super_block *sb)
1217 {
1218 	call_void_hook(sb_delete, sb);
1219 }
1220 
1221 /**
1222  * security_sb_free() - Free a super_block LSM blob
1223  * @sb: filesystem superblock
1224  *
1225  * Deallocate and clear the sb->s_security field.  @sb contains the super_block
1226  * structure to be modified.
1227  */
1228 void security_sb_free(struct super_block *sb)
1229 {
1230 	call_void_hook(sb_free_security, sb);
1231 	kfree(sb->s_security);
1232 	sb->s_security = NULL;
1233 }
1234 
1235 /**
1236  * security_free_mnt_opts() - Free memory associated with mount options
1237  * @mnt_opts: LSM processed mount options
1238  *
1239  * Free memory associated with @mnt_ops.
1240  */
1241 void security_free_mnt_opts(void **mnt_opts)
1242 {
1243 	if (!*mnt_opts)
1244 		return;
1245 	call_void_hook(sb_free_mnt_opts, *mnt_opts);
1246 	*mnt_opts = NULL;
1247 }
1248 EXPORT_SYMBOL(security_free_mnt_opts);
1249 
1250 /**
1251  * security_sb_eat_lsm_opts() - Consume LSM mount options
1252  * @options: mount options
1253  * @mnt_opts: LSM processed mount options
1254  *
1255  * Eat (scan @options) and save them in @mnt_opts.
1256  *
1257  * Return: Returns 0 on success, negative values on failure.
1258  */
1259 int security_sb_eat_lsm_opts(char *options, void **mnt_opts)
1260 {
1261 	return call_int_hook(sb_eat_lsm_opts, 0, options, mnt_opts);
1262 }
1263 EXPORT_SYMBOL(security_sb_eat_lsm_opts);
1264 
1265 /**
1266  * security_sb_mnt_opts_compat() - Check if new mount options are allowed
1267  * @sb: filesystem superblock
1268  * @mnt_opts: new mount options
1269  *
1270  * Determine if the new mount options in @mnt_opts are allowed given the
1271  * existing mounted filesystem at @sb.  @sb superblock being compared.
1272  *
1273  * Return: Returns 0 if options are compatible.
1274  */
1275 int security_sb_mnt_opts_compat(struct super_block *sb,
1276 				void *mnt_opts)
1277 {
1278 	return call_int_hook(sb_mnt_opts_compat, 0, sb, mnt_opts);
1279 }
1280 EXPORT_SYMBOL(security_sb_mnt_opts_compat);
1281 
1282 /**
1283  * security_sb_remount() - Verify no incompatible mount changes during remount
1284  * @sb: filesystem superblock
1285  * @mnt_opts: (re)mount options
1286  *
1287  * Extracts security system specific mount options and verifies no changes are
1288  * being made to those options.
1289  *
1290  * Return: Returns 0 if permission is granted.
1291  */
1292 int security_sb_remount(struct super_block *sb,
1293 			void *mnt_opts)
1294 {
1295 	return call_int_hook(sb_remount, 0, sb, mnt_opts);
1296 }
1297 EXPORT_SYMBOL(security_sb_remount);
1298 
1299 /**
1300  * security_sb_kern_mount() - Check if a kernel mount is allowed
1301  * @sb: filesystem superblock
1302  *
1303  * Mount this @sb if allowed by permissions.
1304  *
1305  * Return: Returns 0 if permission is granted.
1306  */
1307 int security_sb_kern_mount(struct super_block *sb)
1308 {
1309 	return call_int_hook(sb_kern_mount, 0, sb);
1310 }
1311 
1312 /**
1313  * security_sb_show_options() - Output the mount options for a superblock
1314  * @m: output file
1315  * @sb: filesystem superblock
1316  *
1317  * Show (print on @m) mount options for this @sb.
1318  *
1319  * Return: Returns 0 on success, negative values on failure.
1320  */
1321 int security_sb_show_options(struct seq_file *m, struct super_block *sb)
1322 {
1323 	return call_int_hook(sb_show_options, 0, m, sb);
1324 }
1325 
1326 /**
1327  * security_sb_statfs() - Check if accessing fs stats is allowed
1328  * @dentry: superblock handle
1329  *
1330  * Check permission before obtaining filesystem statistics for the @mnt
1331  * mountpoint.  @dentry is a handle on the superblock for the filesystem.
1332  *
1333  * Return: Returns 0 if permission is granted.
1334  */
1335 int security_sb_statfs(struct dentry *dentry)
1336 {
1337 	return call_int_hook(sb_statfs, 0, dentry);
1338 }
1339 
1340 /**
1341  * security_sb_mount() - Check permission for mounting a filesystem
1342  * @dev_name: filesystem backing device
1343  * @path: mount point
1344  * @type: filesystem type
1345  * @flags: mount flags
1346  * @data: filesystem specific data
1347  *
1348  * Check permission before an object specified by @dev_name is mounted on the
1349  * mount point named by @nd.  For an ordinary mount, @dev_name identifies a
1350  * device if the file system type requires a device.  For a remount
1351  * (@flags & MS_REMOUNT), @dev_name is irrelevant.  For a loopback/bind mount
1352  * (@flags & MS_BIND), @dev_name identifies the	pathname of the object being
1353  * mounted.
1354  *
1355  * Return: Returns 0 if permission is granted.
1356  */
1357 int security_sb_mount(const char *dev_name, const struct path *path,
1358 		      const char *type, unsigned long flags, void *data)
1359 {
1360 	return call_int_hook(sb_mount, 0, dev_name, path, type, flags, data);
1361 }
1362 
1363 /**
1364  * security_sb_umount() - Check permission for unmounting a filesystem
1365  * @mnt: mounted filesystem
1366  * @flags: unmount flags
1367  *
1368  * Check permission before the @mnt file system is unmounted.
1369  *
1370  * Return: Returns 0 if permission is granted.
1371  */
1372 int security_sb_umount(struct vfsmount *mnt, int flags)
1373 {
1374 	return call_int_hook(sb_umount, 0, mnt, flags);
1375 }
1376 
1377 /**
1378  * security_sb_pivotroot() - Check permissions for pivoting the rootfs
1379  * @old_path: new location for current rootfs
1380  * @new_path: location of the new rootfs
1381  *
1382  * Check permission before pivoting the root filesystem.
1383  *
1384  * Return: Returns 0 if permission is granted.
1385  */
1386 int security_sb_pivotroot(const struct path *old_path,
1387 			  const struct path *new_path)
1388 {
1389 	return call_int_hook(sb_pivotroot, 0, old_path, new_path);
1390 }
1391 
1392 /**
1393  * security_sb_set_mnt_opts() - Set the mount options for a filesystem
1394  * @sb: filesystem superblock
1395  * @mnt_opts: binary mount options
1396  * @kern_flags: kernel flags (in)
1397  * @set_kern_flags: kernel flags (out)
1398  *
1399  * Set the security relevant mount options used for a superblock.
1400  *
1401  * Return: Returns 0 on success, error on failure.
1402  */
1403 int security_sb_set_mnt_opts(struct super_block *sb,
1404 			     void *mnt_opts,
1405 			     unsigned long kern_flags,
1406 			     unsigned long *set_kern_flags)
1407 {
1408 	return call_int_hook(sb_set_mnt_opts,
1409 			     mnt_opts ? -EOPNOTSUPP : 0, sb,
1410 			     mnt_opts, kern_flags, set_kern_flags);
1411 }
1412 EXPORT_SYMBOL(security_sb_set_mnt_opts);
1413 
1414 /**
1415  * security_sb_clone_mnt_opts() - Duplicate superblock mount options
1416  * @oldsb: source superblock
1417  * @newsb: destination superblock
1418  * @kern_flags: kernel flags (in)
1419  * @set_kern_flags: kernel flags (out)
1420  *
1421  * Copy all security options from a given superblock to another.
1422  *
1423  * Return: Returns 0 on success, error on failure.
1424  */
1425 int security_sb_clone_mnt_opts(const struct super_block *oldsb,
1426 			       struct super_block *newsb,
1427 			       unsigned long kern_flags,
1428 			       unsigned long *set_kern_flags)
1429 {
1430 	return call_int_hook(sb_clone_mnt_opts, 0, oldsb, newsb,
1431 			     kern_flags, set_kern_flags);
1432 }
1433 EXPORT_SYMBOL(security_sb_clone_mnt_opts);
1434 
1435 /**
1436  * security_move_mount() - Check permissions for moving a mount
1437  * @from_path: source mount point
1438  * @to_path: destination mount point
1439  *
1440  * Check permission before a mount is moved.
1441  *
1442  * Return: Returns 0 if permission is granted.
1443  */
1444 int security_move_mount(const struct path *from_path,
1445 			const struct path *to_path)
1446 {
1447 	return call_int_hook(move_mount, 0, from_path, to_path);
1448 }
1449 
1450 /**
1451  * security_path_notify() - Check if setting a watch is allowed
1452  * @path: file path
1453  * @mask: event mask
1454  * @obj_type: file path type
1455  *
1456  * Check permissions before setting a watch on events as defined by @mask, on
1457  * an object at @path, whose type is defined by @obj_type.
1458  *
1459  * Return: Returns 0 if permission is granted.
1460  */
1461 int security_path_notify(const struct path *path, u64 mask,
1462 			 unsigned int obj_type)
1463 {
1464 	return call_int_hook(path_notify, 0, path, mask, obj_type);
1465 }
1466 
1467 /**
1468  * security_inode_alloc() - Allocate an inode LSM blob
1469  * @inode: the inode
1470  *
1471  * Allocate and attach a security structure to @inode->i_security.  The
1472  * i_security field is initialized to NULL when the inode structure is
1473  * allocated.
1474  *
1475  * Return: Return 0 if operation was successful.
1476  */
1477 int security_inode_alloc(struct inode *inode)
1478 {
1479 	int rc = lsm_inode_alloc(inode);
1480 
1481 	if (unlikely(rc))
1482 		return rc;
1483 	rc = call_int_hook(inode_alloc_security, 0, inode);
1484 	if (unlikely(rc))
1485 		security_inode_free(inode);
1486 	return rc;
1487 }
1488 
1489 static void inode_free_by_rcu(struct rcu_head *head)
1490 {
1491 	/*
1492 	 * The rcu head is at the start of the inode blob
1493 	 */
1494 	kmem_cache_free(lsm_inode_cache, head);
1495 }
1496 
1497 /**
1498  * security_inode_free() - Free an inode's LSM blob
1499  * @inode: the inode
1500  *
1501  * Deallocate the inode security structure and set @inode->i_security to NULL.
1502  */
1503 void security_inode_free(struct inode *inode)
1504 {
1505 	integrity_inode_free(inode);
1506 	call_void_hook(inode_free_security, inode);
1507 	/*
1508 	 * The inode may still be referenced in a path walk and
1509 	 * a call to security_inode_permission() can be made
1510 	 * after inode_free_security() is called. Ideally, the VFS
1511 	 * wouldn't do this, but fixing that is a much harder
1512 	 * job. For now, simply free the i_security via RCU, and
1513 	 * leave the current inode->i_security pointer intact.
1514 	 * The inode will be freed after the RCU grace period too.
1515 	 */
1516 	if (inode->i_security)
1517 		call_rcu((struct rcu_head *)inode->i_security,
1518 			 inode_free_by_rcu);
1519 }
1520 
1521 /**
1522  * security_dentry_init_security() - Perform dentry initialization
1523  * @dentry: the dentry to initialize
1524  * @mode: mode used to determine resource type
1525  * @name: name of the last path component
1526  * @xattr_name: name of the security/LSM xattr
1527  * @ctx: pointer to the resulting LSM context
1528  * @ctxlen: length of @ctx
1529  *
1530  * Compute a context for a dentry as the inode is not yet available since NFSv4
1531  * has no label backed by an EA anyway.  It is important to note that
1532  * @xattr_name does not need to be free'd by the caller, it is a static string.
1533  *
1534  * Return: Returns 0 on success, negative values on failure.
1535  */
1536 int security_dentry_init_security(struct dentry *dentry, int mode,
1537 				  const struct qstr *name,
1538 				  const char **xattr_name, void **ctx,
1539 				  u32 *ctxlen)
1540 {
1541 	struct security_hook_list *hp;
1542 	int rc;
1543 
1544 	/*
1545 	 * Only one module will provide a security context.
1546 	 */
1547 	hlist_for_each_entry(hp, &security_hook_heads.dentry_init_security,
1548 			     list) {
1549 		rc = hp->hook.dentry_init_security(dentry, mode, name,
1550 						   xattr_name, ctx, ctxlen);
1551 		if (rc != LSM_RET_DEFAULT(dentry_init_security))
1552 			return rc;
1553 	}
1554 	return LSM_RET_DEFAULT(dentry_init_security);
1555 }
1556 EXPORT_SYMBOL(security_dentry_init_security);
1557 
1558 /**
1559  * security_dentry_create_files_as() - Perform dentry initialization
1560  * @dentry: the dentry to initialize
1561  * @mode: mode used to determine resource type
1562  * @name: name of the last path component
1563  * @old: creds to use for LSM context calculations
1564  * @new: creds to modify
1565  *
1566  * Compute a context for a dentry as the inode is not yet available and set
1567  * that context in passed in creds so that new files are created using that
1568  * context. Context is calculated using the passed in creds and not the creds
1569  * of the caller.
1570  *
1571  * Return: Returns 0 on success, error on failure.
1572  */
1573 int security_dentry_create_files_as(struct dentry *dentry, int mode,
1574 				    struct qstr *name,
1575 				    const struct cred *old, struct cred *new)
1576 {
1577 	return call_int_hook(dentry_create_files_as, 0, dentry, mode,
1578 			     name, old, new);
1579 }
1580 EXPORT_SYMBOL(security_dentry_create_files_as);
1581 
1582 /**
1583  * security_inode_init_security() - Initialize an inode's LSM context
1584  * @inode: the inode
1585  * @dir: parent directory
1586  * @qstr: last component of the pathname
1587  * @initxattrs: callback function to write xattrs
1588  * @fs_data: filesystem specific data
1589  *
1590  * Obtain the security attribute name suffix and value to set on a newly
1591  * created inode and set up the incore security field for the new inode.  This
1592  * hook is called by the fs code as part of the inode creation transaction and
1593  * provides for atomic labeling of the inode, unlike the post_create/mkdir/...
1594  * hooks called by the VFS.  The hook function is expected to allocate the name
1595  * and value via kmalloc, with the caller being responsible for calling kfree
1596  * after using them.  If the security module does not use security attributes
1597  * or does not wish to put a security attribute on this particular inode, then
1598  * it should return -EOPNOTSUPP to skip this processing.
1599  *
1600  * Return: Returns 0 on success, -EOPNOTSUPP if no security attribute is
1601  * needed, or -ENOMEM on memory allocation failure.
1602  */
1603 int security_inode_init_security(struct inode *inode, struct inode *dir,
1604 				 const struct qstr *qstr,
1605 				 const initxattrs initxattrs, void *fs_data)
1606 {
1607 	struct xattr new_xattrs[MAX_LSM_EVM_XATTR + 1];
1608 	struct xattr *lsm_xattr, *evm_xattr, *xattr;
1609 	int ret;
1610 
1611 	if (unlikely(IS_PRIVATE(inode)))
1612 		return 0;
1613 
1614 	if (!initxattrs)
1615 		return call_int_hook(inode_init_security, -EOPNOTSUPP, inode,
1616 				     dir, qstr, NULL, NULL, NULL);
1617 	memset(new_xattrs, 0, sizeof(new_xattrs));
1618 	lsm_xattr = new_xattrs;
1619 	ret = call_int_hook(inode_init_security, -EOPNOTSUPP, inode, dir, qstr,
1620 			    &lsm_xattr->name,
1621 			    &lsm_xattr->value,
1622 			    &lsm_xattr->value_len);
1623 	if (ret)
1624 		goto out;
1625 
1626 	evm_xattr = lsm_xattr + 1;
1627 	ret = evm_inode_init_security(inode, lsm_xattr, evm_xattr);
1628 	if (ret)
1629 		goto out;
1630 	ret = initxattrs(inode, new_xattrs, fs_data);
1631 out:
1632 	for (xattr = new_xattrs; xattr->value != NULL; xattr++)
1633 		kfree(xattr->value);
1634 	return (ret == -EOPNOTSUPP) ? 0 : ret;
1635 }
1636 EXPORT_SYMBOL(security_inode_init_security);
1637 
1638 /**
1639  * security_inode_init_security_anon() - Initialize an anonymous inode
1640  * @inode: the inode
1641  * @name: the anonymous inode class
1642  * @context_inode: an optional related inode
1643  *
1644  * Set up the incore security field for the new anonymous inode and return
1645  * whether the inode creation is permitted by the security module or not.
1646  *
1647  * Return: Returns 0 on success, -EACCES if the security module denies the
1648  * creation of this inode, or another -errno upon other errors.
1649  */
1650 int security_inode_init_security_anon(struct inode *inode,
1651 				      const struct qstr *name,
1652 				      const struct inode *context_inode)
1653 {
1654 	return call_int_hook(inode_init_security_anon, 0, inode, name,
1655 			     context_inode);
1656 }
1657 
1658 #ifdef CONFIG_SECURITY_PATH
1659 /**
1660  * security_path_mknod() - Check if creating a special file is allowed
1661  * @dir: parent directory
1662  * @dentry: new file
1663  * @mode: new file mode
1664  * @dev: device number
1665  *
1666  * Check permissions when creating a file. Note that this hook is called even
1667  * if mknod operation is being done for a regular file.
1668  *
1669  * Return: Returns 0 if permission is granted.
1670  */
1671 int security_path_mknod(const struct path *dir, struct dentry *dentry,
1672 			umode_t mode, unsigned int dev)
1673 {
1674 	if (unlikely(IS_PRIVATE(d_backing_inode(dir->dentry))))
1675 		return 0;
1676 	return call_int_hook(path_mknod, 0, dir, dentry, mode, dev);
1677 }
1678 EXPORT_SYMBOL(security_path_mknod);
1679 
1680 /**
1681  * security_path_mkdir() - Check if creating a new directory is allowed
1682  * @dir: parent directory
1683  * @dentry: new directory
1684  * @mode: new directory mode
1685  *
1686  * Check permissions to create a new directory in the existing directory.
1687  *
1688  * Return: Returns 0 if permission is granted.
1689  */
1690 int security_path_mkdir(const struct path *dir, struct dentry *dentry,
1691 			umode_t mode)
1692 {
1693 	if (unlikely(IS_PRIVATE(d_backing_inode(dir->dentry))))
1694 		return 0;
1695 	return call_int_hook(path_mkdir, 0, dir, dentry, mode);
1696 }
1697 EXPORT_SYMBOL(security_path_mkdir);
1698 
1699 /**
1700  * security_path_rmdir() - Check if removing a directory is allowed
1701  * @dir: parent directory
1702  * @dentry: directory to remove
1703  *
1704  * Check the permission to remove a directory.
1705  *
1706  * Return: Returns 0 if permission is granted.
1707  */
1708 int security_path_rmdir(const struct path *dir, struct dentry *dentry)
1709 {
1710 	if (unlikely(IS_PRIVATE(d_backing_inode(dir->dentry))))
1711 		return 0;
1712 	return call_int_hook(path_rmdir, 0, dir, dentry);
1713 }
1714 
1715 /**
1716  * security_path_unlink() - Check if removing a hard link is allowed
1717  * @dir: parent directory
1718  * @dentry: file
1719  *
1720  * Check the permission to remove a hard link to a file.
1721  *
1722  * Return: Returns 0 if permission is granted.
1723  */
1724 int security_path_unlink(const struct path *dir, struct dentry *dentry)
1725 {
1726 	if (unlikely(IS_PRIVATE(d_backing_inode(dir->dentry))))
1727 		return 0;
1728 	return call_int_hook(path_unlink, 0, dir, dentry);
1729 }
1730 EXPORT_SYMBOL(security_path_unlink);
1731 
1732 /**
1733  * security_path_symlink() - Check if creating a symbolic link is allowed
1734  * @dir: parent directory
1735  * @dentry: symbolic link
1736  * @old_name: file pathname
1737  *
1738  * Check the permission to create a symbolic link to a file.
1739  *
1740  * Return: Returns 0 if permission is granted.
1741  */
1742 int security_path_symlink(const struct path *dir, struct dentry *dentry,
1743 			  const char *old_name)
1744 {
1745 	if (unlikely(IS_PRIVATE(d_backing_inode(dir->dentry))))
1746 		return 0;
1747 	return call_int_hook(path_symlink, 0, dir, dentry, old_name);
1748 }
1749 
1750 /**
1751  * security_path_link - Check if creating a hard link is allowed
1752  * @old_dentry: existing file
1753  * @new_dir: new parent directory
1754  * @new_dentry: new link
1755  *
1756  * Check permission before creating a new hard link to a file.
1757  *
1758  * Return: Returns 0 if permission is granted.
1759  */
1760 int security_path_link(struct dentry *old_dentry, const struct path *new_dir,
1761 		       struct dentry *new_dentry)
1762 {
1763 	if (unlikely(IS_PRIVATE(d_backing_inode(old_dentry))))
1764 		return 0;
1765 	return call_int_hook(path_link, 0, old_dentry, new_dir, new_dentry);
1766 }
1767 
1768 /**
1769  * security_path_rename() - Check if renaming a file is allowed
1770  * @old_dir: parent directory of the old file
1771  * @old_dentry: the old file
1772  * @new_dir: parent directory of the new file
1773  * @new_dentry: the new file
1774  * @flags: flags
1775  *
1776  * Check for permission to rename a file or directory.
1777  *
1778  * Return: Returns 0 if permission is granted.
1779  */
1780 int security_path_rename(const struct path *old_dir, struct dentry *old_dentry,
1781 			 const struct path *new_dir, struct dentry *new_dentry,
1782 			 unsigned int flags)
1783 {
1784 	if (unlikely(IS_PRIVATE(d_backing_inode(old_dentry)) ||
1785 		     (d_is_positive(new_dentry) &&
1786 		      IS_PRIVATE(d_backing_inode(new_dentry)))))
1787 		return 0;
1788 
1789 	return call_int_hook(path_rename, 0, old_dir, old_dentry, new_dir,
1790 			     new_dentry, flags);
1791 }
1792 EXPORT_SYMBOL(security_path_rename);
1793 
1794 /**
1795  * security_path_truncate() - Check if truncating a file is allowed
1796  * @path: file
1797  *
1798  * Check permission before truncating the file indicated by path.  Note that
1799  * truncation permissions may also be checked based on already opened files,
1800  * using the security_file_truncate() hook.
1801  *
1802  * Return: Returns 0 if permission is granted.
1803  */
1804 int security_path_truncate(const struct path *path)
1805 {
1806 	if (unlikely(IS_PRIVATE(d_backing_inode(path->dentry))))
1807 		return 0;
1808 	return call_int_hook(path_truncate, 0, path);
1809 }
1810 
1811 /**
1812  * security_path_chmod() - Check if changing the file's mode is allowed
1813  * @path: file
1814  * @mode: new mode
1815  *
1816  * Check for permission to change a mode of the file @path. The new mode is
1817  * specified in @mode which is a bitmask of constants from
1818  * <include/uapi/linux/stat.h>.
1819  *
1820  * Return: Returns 0 if permission is granted.
1821  */
1822 int security_path_chmod(const struct path *path, umode_t mode)
1823 {
1824 	if (unlikely(IS_PRIVATE(d_backing_inode(path->dentry))))
1825 		return 0;
1826 	return call_int_hook(path_chmod, 0, path, mode);
1827 }
1828 
1829 /**
1830  * security_path_chown() - Check if changing the file's owner/group is allowed
1831  * @path: file
1832  * @uid: file owner
1833  * @gid: file group
1834  *
1835  * Check for permission to change owner/group of a file or directory.
1836  *
1837  * Return: Returns 0 if permission is granted.
1838  */
1839 int security_path_chown(const struct path *path, kuid_t uid, kgid_t gid)
1840 {
1841 	if (unlikely(IS_PRIVATE(d_backing_inode(path->dentry))))
1842 		return 0;
1843 	return call_int_hook(path_chown, 0, path, uid, gid);
1844 }
1845 
1846 /**
1847  * security_path_chroot() - Check if changing the root directory is allowed
1848  * @path: directory
1849  *
1850  * Check for permission to change root directory.
1851  *
1852  * Return: Returns 0 if permission is granted.
1853  */
1854 int security_path_chroot(const struct path *path)
1855 {
1856 	return call_int_hook(path_chroot, 0, path);
1857 }
1858 #endif /* CONFIG_SECURITY_PATH */
1859 
1860 /**
1861  * security_inode_create() - Check if creating a file is allowed
1862  * @dir: the parent directory
1863  * @dentry: the file being created
1864  * @mode: requested file mode
1865  *
1866  * Check permission to create a regular file.
1867  *
1868  * Return: Returns 0 if permission is granted.
1869  */
1870 int security_inode_create(struct inode *dir, struct dentry *dentry,
1871 			  umode_t mode)
1872 {
1873 	if (unlikely(IS_PRIVATE(dir)))
1874 		return 0;
1875 	return call_int_hook(inode_create, 0, dir, dentry, mode);
1876 }
1877 EXPORT_SYMBOL_GPL(security_inode_create);
1878 
1879 /**
1880  * security_inode_link() - Check if creating a hard link is allowed
1881  * @old_dentry: existing file
1882  * @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_inode_link(struct dentry *old_dentry, struct inode *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(inode_link, 0, old_dentry, dir, new_dentry);
1895 }
1896 
1897 /**
1898  * security_inode_unlink() - Check if removing a hard link is allowed
1899  * @dir: parent directory
1900  * @dentry: file
1901  *
1902  * Check the permission to remove a hard link to a file.
1903  *
1904  * Return: Returns 0 if permission is granted.
1905  */
1906 int security_inode_unlink(struct inode *dir, struct dentry *dentry)
1907 {
1908 	if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
1909 		return 0;
1910 	return call_int_hook(inode_unlink, 0, dir, dentry);
1911 }
1912 
1913 /**
1914  * security_inode_symlink() - Check if creating a symbolic link is allowed
1915  * @dir: parent directory
1916  * @dentry: symbolic link
1917  * @old_name: existing filename
1918  *
1919  * Check the permission to create a symbolic link to a file.
1920  *
1921  * Return: Returns 0 if permission is granted.
1922  */
1923 int security_inode_symlink(struct inode *dir, struct dentry *dentry,
1924 			   const char *old_name)
1925 {
1926 	if (unlikely(IS_PRIVATE(dir)))
1927 		return 0;
1928 	return call_int_hook(inode_symlink, 0, dir, dentry, old_name);
1929 }
1930 
1931 /**
1932  * security_inode_mkdir() - Check if creation a new director is allowed
1933  * @dir: parent directory
1934  * @dentry: new directory
1935  * @mode: new directory mode
1936  *
1937  * Check permissions to create a new directory in the existing directory
1938  * associated with inode structure @dir.
1939  *
1940  * Return: Returns 0 if permission is granted.
1941  */
1942 int security_inode_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
1943 {
1944 	if (unlikely(IS_PRIVATE(dir)))
1945 		return 0;
1946 	return call_int_hook(inode_mkdir, 0, dir, dentry, mode);
1947 }
1948 EXPORT_SYMBOL_GPL(security_inode_mkdir);
1949 
1950 /**
1951  * security_inode_rmdir() - Check if removing a directory is allowed
1952  * @dir: parent directory
1953  * @dentry: directory to be removed
1954  *
1955  * Check the permission to remove a directory.
1956  *
1957  * Return: Returns 0 if permission is granted.
1958  */
1959 int security_inode_rmdir(struct inode *dir, struct dentry *dentry)
1960 {
1961 	if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
1962 		return 0;
1963 	return call_int_hook(inode_rmdir, 0, dir, dentry);
1964 }
1965 
1966 /**
1967  * security_inode_mknod() - Check if creating a special file is allowed
1968  * @dir: parent directory
1969  * @dentry: new file
1970  * @mode: new file mode
1971  * @dev: device number
1972  *
1973  * Check permissions when creating a special file (or a socket or a fifo file
1974  * created via the mknod system call).  Note that if mknod operation is being
1975  * done for a regular file, then the create hook will be called and not this
1976  * hook.
1977  *
1978  * Return: Returns 0 if permission is granted.
1979  */
1980 int security_inode_mknod(struct inode *dir, struct dentry *dentry,
1981 			 umode_t mode, dev_t dev)
1982 {
1983 	if (unlikely(IS_PRIVATE(dir)))
1984 		return 0;
1985 	return call_int_hook(inode_mknod, 0, dir, dentry, mode, dev);
1986 }
1987 
1988 /**
1989  * security_inode_rename() - Check if renaming a file is allowed
1990  * @old_dir: parent directory of the old file
1991  * @old_dentry: the old file
1992  * @new_dir: parent directory of the new file
1993  * @new_dentry: the new file
1994  * @flags: flags
1995  *
1996  * Check for permission to rename a file or directory.
1997  *
1998  * Return: Returns 0 if permission is granted.
1999  */
2000 int security_inode_rename(struct inode *old_dir, struct dentry *old_dentry,
2001 			  struct inode *new_dir, struct dentry *new_dentry,
2002 			  unsigned int flags)
2003 {
2004 	if (unlikely(IS_PRIVATE(d_backing_inode(old_dentry)) ||
2005 		     (d_is_positive(new_dentry) &&
2006 		      IS_PRIVATE(d_backing_inode(new_dentry)))))
2007 		return 0;
2008 
2009 	if (flags & RENAME_EXCHANGE) {
2010 		int err = call_int_hook(inode_rename, 0, new_dir, new_dentry,
2011 					old_dir, old_dentry);
2012 		if (err)
2013 			return err;
2014 	}
2015 
2016 	return call_int_hook(inode_rename, 0, old_dir, old_dentry,
2017 			     new_dir, new_dentry);
2018 }
2019 
2020 /**
2021  * security_inode_readlink() - Check if reading a symbolic link is allowed
2022  * @dentry: link
2023  *
2024  * Check the permission to read the symbolic link.
2025  *
2026  * Return: Returns 0 if permission is granted.
2027  */
2028 int security_inode_readlink(struct dentry *dentry)
2029 {
2030 	if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
2031 		return 0;
2032 	return call_int_hook(inode_readlink, 0, dentry);
2033 }
2034 
2035 /**
2036  * security_inode_follow_link() - Check if following a symbolic link is allowed
2037  * @dentry: link dentry
2038  * @inode: link inode
2039  * @rcu: true if in RCU-walk mode
2040  *
2041  * Check permission to follow a symbolic link when looking up a pathname.  If
2042  * @rcu is true, @inode is not stable.
2043  *
2044  * Return: Returns 0 if permission is granted.
2045  */
2046 int security_inode_follow_link(struct dentry *dentry, struct inode *inode,
2047 			       bool rcu)
2048 {
2049 	if (unlikely(IS_PRIVATE(inode)))
2050 		return 0;
2051 	return call_int_hook(inode_follow_link, 0, dentry, inode, rcu);
2052 }
2053 
2054 /**
2055  * security_inode_permission() - Check if accessing an inode is allowed
2056  * @inode: inode
2057  * @mask: access mask
2058  *
2059  * Check permission before accessing an inode.  This hook is called by the
2060  * existing Linux permission function, so a security module can use it to
2061  * provide additional checking for existing Linux permission checks.  Notice
2062  * that this hook is called when a file is opened (as well as many other
2063  * operations), whereas the file_security_ops permission hook is called when
2064  * the actual read/write operations are performed.
2065  *
2066  * Return: Returns 0 if permission is granted.
2067  */
2068 int security_inode_permission(struct inode *inode, int mask)
2069 {
2070 	if (unlikely(IS_PRIVATE(inode)))
2071 		return 0;
2072 	return call_int_hook(inode_permission, 0, inode, mask);
2073 }
2074 
2075 /**
2076  * security_inode_setattr() - Check if setting file attributes is allowed
2077  * @idmap: idmap of the mount
2078  * @dentry: file
2079  * @attr: new attributes
2080  *
2081  * Check permission before setting file attributes.  Note that the kernel call
2082  * to notify_change is performed from several locations, whenever file
2083  * attributes change (such as when a file is truncated, chown/chmod operations,
2084  * transferring disk quotas, etc).
2085  *
2086  * Return: Returns 0 if permission is granted.
2087  */
2088 int security_inode_setattr(struct mnt_idmap *idmap,
2089 			   struct dentry *dentry, struct iattr *attr)
2090 {
2091 	int ret;
2092 
2093 	if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
2094 		return 0;
2095 	ret = call_int_hook(inode_setattr, 0, dentry, attr);
2096 	if (ret)
2097 		return ret;
2098 	return evm_inode_setattr(idmap, dentry, attr);
2099 }
2100 EXPORT_SYMBOL_GPL(security_inode_setattr);
2101 
2102 /**
2103  * security_inode_getattr() - Check if getting file attributes is allowed
2104  * @path: file
2105  *
2106  * Check permission before obtaining file attributes.
2107  *
2108  * Return: Returns 0 if permission is granted.
2109  */
2110 int security_inode_getattr(const struct path *path)
2111 {
2112 	if (unlikely(IS_PRIVATE(d_backing_inode(path->dentry))))
2113 		return 0;
2114 	return call_int_hook(inode_getattr, 0, path);
2115 }
2116 
2117 /**
2118  * security_inode_setxattr() - Check if setting file xattrs is allowed
2119  * @idmap: idmap of the mount
2120  * @dentry: file
2121  * @name: xattr name
2122  * @value: xattr value
2123  * @size: size of xattr value
2124  * @flags: flags
2125  *
2126  * Check permission before setting the extended attributes.
2127  *
2128  * Return: Returns 0 if permission is granted.
2129  */
2130 int security_inode_setxattr(struct mnt_idmap *idmap,
2131 			    struct dentry *dentry, const char *name,
2132 			    const void *value, size_t size, int flags)
2133 {
2134 	int ret;
2135 
2136 	if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
2137 		return 0;
2138 	/*
2139 	 * SELinux and Smack integrate the cap call,
2140 	 * so assume that all LSMs supplying this call do so.
2141 	 */
2142 	ret = call_int_hook(inode_setxattr, 1, idmap, dentry, name, value,
2143 			    size, flags);
2144 
2145 	if (ret == 1)
2146 		ret = cap_inode_setxattr(dentry, name, value, size, flags);
2147 	if (ret)
2148 		return ret;
2149 	ret = ima_inode_setxattr(dentry, name, value, size);
2150 	if (ret)
2151 		return ret;
2152 	return evm_inode_setxattr(idmap, dentry, name, value, size);
2153 }
2154 
2155 /**
2156  * security_inode_set_acl() - Check if setting posix acls is allowed
2157  * @idmap: idmap of the mount
2158  * @dentry: file
2159  * @acl_name: acl name
2160  * @kacl: acl struct
2161  *
2162  * Check permission before setting posix acls, the posix acls in @kacl are
2163  * identified by @acl_name.
2164  *
2165  * Return: Returns 0 if permission is granted.
2166  */
2167 int security_inode_set_acl(struct mnt_idmap *idmap,
2168 			   struct dentry *dentry, const char *acl_name,
2169 			   struct posix_acl *kacl)
2170 {
2171 	int ret;
2172 
2173 	if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
2174 		return 0;
2175 	ret = call_int_hook(inode_set_acl, 0, idmap, dentry, acl_name,
2176 			    kacl);
2177 	if (ret)
2178 		return ret;
2179 	ret = ima_inode_set_acl(idmap, dentry, acl_name, kacl);
2180 	if (ret)
2181 		return ret;
2182 	return evm_inode_set_acl(idmap, dentry, acl_name, kacl);
2183 }
2184 
2185 /**
2186  * security_inode_get_acl() - Check if reading posix acls is allowed
2187  * @idmap: idmap of the mount
2188  * @dentry: file
2189  * @acl_name: acl name
2190  *
2191  * Check permission before getting osix acls, the posix acls are identified by
2192  * @acl_name.
2193  *
2194  * Return: Returns 0 if permission is granted.
2195  */
2196 int security_inode_get_acl(struct mnt_idmap *idmap,
2197 			   struct dentry *dentry, const char *acl_name)
2198 {
2199 	if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
2200 		return 0;
2201 	return call_int_hook(inode_get_acl, 0, idmap, dentry, acl_name);
2202 }
2203 
2204 /**
2205  * security_inode_remove_acl() - Check if removing a posix acl is allowed
2206  * @idmap: idmap of the mount
2207  * @dentry: file
2208  * @acl_name: acl name
2209  *
2210  * Check permission before removing posix acls, the posix acls are identified
2211  * by @acl_name.
2212  *
2213  * Return: Returns 0 if permission is granted.
2214  */
2215 int security_inode_remove_acl(struct mnt_idmap *idmap,
2216 			      struct dentry *dentry, const char *acl_name)
2217 {
2218 	int ret;
2219 
2220 	if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
2221 		return 0;
2222 	ret = call_int_hook(inode_remove_acl, 0, idmap, dentry, acl_name);
2223 	if (ret)
2224 		return ret;
2225 	ret = ima_inode_remove_acl(idmap, dentry, acl_name);
2226 	if (ret)
2227 		return ret;
2228 	return evm_inode_remove_acl(idmap, dentry, acl_name);
2229 }
2230 
2231 /**
2232  * security_inode_post_setxattr() - Update the inode after a setxattr operation
2233  * @dentry: file
2234  * @name: xattr name
2235  * @value: xattr value
2236  * @size: xattr value size
2237  * @flags: flags
2238  *
2239  * Update inode security field after successful setxattr operation.
2240  */
2241 void security_inode_post_setxattr(struct dentry *dentry, const char *name,
2242 				  const void *value, size_t size, int flags)
2243 {
2244 	if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
2245 		return;
2246 	call_void_hook(inode_post_setxattr, dentry, name, value, size, flags);
2247 	evm_inode_post_setxattr(dentry, name, value, size);
2248 }
2249 
2250 /**
2251  * security_inode_getxattr() - Check if xattr access is allowed
2252  * @dentry: file
2253  * @name: xattr name
2254  *
2255  * Check permission before obtaining the extended attributes identified by
2256  * @name for @dentry.
2257  *
2258  * Return: Returns 0 if permission is granted.
2259  */
2260 int security_inode_getxattr(struct dentry *dentry, const char *name)
2261 {
2262 	if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
2263 		return 0;
2264 	return call_int_hook(inode_getxattr, 0, dentry, name);
2265 }
2266 
2267 /**
2268  * security_inode_listxattr() - Check if listing xattrs is allowed
2269  * @dentry: file
2270  *
2271  * Check permission before obtaining the list of extended attribute names for
2272  * @dentry.
2273  *
2274  * Return: Returns 0 if permission is granted.
2275  */
2276 int security_inode_listxattr(struct dentry *dentry)
2277 {
2278 	if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
2279 		return 0;
2280 	return call_int_hook(inode_listxattr, 0, dentry);
2281 }
2282 
2283 /**
2284  * security_inode_removexattr() - Check if removing an xattr is allowed
2285  * @idmap: idmap of the mount
2286  * @dentry: file
2287  * @name: xattr name
2288  *
2289  * Check permission before removing the extended attribute identified by @name
2290  * for @dentry.
2291  *
2292  * Return: Returns 0 if permission is granted.
2293  */
2294 int security_inode_removexattr(struct mnt_idmap *idmap,
2295 			       struct dentry *dentry, const char *name)
2296 {
2297 	int ret;
2298 
2299 	if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
2300 		return 0;
2301 	/*
2302 	 * SELinux and Smack integrate the cap call,
2303 	 * so assume that all LSMs supplying this call do so.
2304 	 */
2305 	ret = call_int_hook(inode_removexattr, 1, idmap, dentry, name);
2306 	if (ret == 1)
2307 		ret = cap_inode_removexattr(idmap, dentry, name);
2308 	if (ret)
2309 		return ret;
2310 	ret = ima_inode_removexattr(dentry, name);
2311 	if (ret)
2312 		return ret;
2313 	return evm_inode_removexattr(idmap, dentry, name);
2314 }
2315 
2316 /**
2317  * security_inode_need_killpriv() - Check if security_inode_killpriv() required
2318  * @dentry: associated dentry
2319  *
2320  * Called when an inode has been changed to determine if
2321  * security_inode_killpriv() should be called.
2322  *
2323  * Return: Return <0 on error to abort the inode change operation, return 0 if
2324  *         security_inode_killpriv() does not need to be called, return >0 if
2325  *         security_inode_killpriv() does need to be called.
2326  */
2327 int security_inode_need_killpriv(struct dentry *dentry)
2328 {
2329 	return call_int_hook(inode_need_killpriv, 0, dentry);
2330 }
2331 
2332 /**
2333  * security_inode_killpriv() - The setuid bit is removed, update LSM state
2334  * @idmap: idmap of the mount
2335  * @dentry: associated dentry
2336  *
2337  * The @dentry's setuid bit is being removed.  Remove similar security labels.
2338  * Called with the dentry->d_inode->i_mutex held.
2339  *
2340  * Return: Return 0 on success.  If error is returned, then the operation
2341  *         causing setuid bit removal is failed.
2342  */
2343 int security_inode_killpriv(struct mnt_idmap *idmap,
2344 			    struct dentry *dentry)
2345 {
2346 	return call_int_hook(inode_killpriv, 0, idmap, dentry);
2347 }
2348 
2349 /**
2350  * security_inode_getsecurity() - Get the xattr security label of an inode
2351  * @idmap: idmap of the mount
2352  * @inode: inode
2353  * @name: xattr name
2354  * @buffer: security label buffer
2355  * @alloc: allocation flag
2356  *
2357  * Retrieve a copy of the extended attribute representation of the security
2358  * label associated with @name for @inode via @buffer.  Note that @name is the
2359  * remainder of the attribute name after the security prefix has been removed.
2360  * @alloc is used to specify if the call should return a value via the buffer
2361  * or just the value length.
2362  *
2363  * Return: Returns size of buffer on success.
2364  */
2365 int security_inode_getsecurity(struct mnt_idmap *idmap,
2366 			       struct inode *inode, const char *name,
2367 			       void **buffer, bool alloc)
2368 {
2369 	struct security_hook_list *hp;
2370 	int rc;
2371 
2372 	if (unlikely(IS_PRIVATE(inode)))
2373 		return LSM_RET_DEFAULT(inode_getsecurity);
2374 	/*
2375 	 * Only one module will provide an attribute with a given name.
2376 	 */
2377 	hlist_for_each_entry(hp, &security_hook_heads.inode_getsecurity, list) {
2378 		rc = hp->hook.inode_getsecurity(idmap, inode, name, buffer,
2379 						alloc);
2380 		if (rc != LSM_RET_DEFAULT(inode_getsecurity))
2381 			return rc;
2382 	}
2383 	return LSM_RET_DEFAULT(inode_getsecurity);
2384 }
2385 
2386 /**
2387  * security_inode_setsecurity() - Set the xattr security label of an inode
2388  * @inode: inode
2389  * @name: xattr name
2390  * @value: security label
2391  * @size: length of security label
2392  * @flags: flags
2393  *
2394  * Set the security label associated with @name for @inode from the extended
2395  * attribute value @value.  @size indicates the size of the @value in bytes.
2396  * @flags may be XATTR_CREATE, XATTR_REPLACE, or 0. Note that @name is the
2397  * remainder of the attribute name after the security. prefix has been removed.
2398  *
2399  * Return: Returns 0 on success.
2400  */
2401 int security_inode_setsecurity(struct inode *inode, const char *name,
2402 			       const void *value, size_t size, int flags)
2403 {
2404 	struct security_hook_list *hp;
2405 	int rc;
2406 
2407 	if (unlikely(IS_PRIVATE(inode)))
2408 		return LSM_RET_DEFAULT(inode_setsecurity);
2409 	/*
2410 	 * Only one module will provide an attribute with a given name.
2411 	 */
2412 	hlist_for_each_entry(hp, &security_hook_heads.inode_setsecurity, list) {
2413 		rc = hp->hook.inode_setsecurity(inode, name, value, size,
2414 						flags);
2415 		if (rc != LSM_RET_DEFAULT(inode_setsecurity))
2416 			return rc;
2417 	}
2418 	return LSM_RET_DEFAULT(inode_setsecurity);
2419 }
2420 
2421 /**
2422  * security_inode_listsecurity() - List the xattr security label names
2423  * @inode: inode
2424  * @buffer: buffer
2425  * @buffer_size: size of buffer
2426  *
2427  * Copy the extended attribute names for the security labels associated with
2428  * @inode into @buffer.  The maximum size of @buffer is specified by
2429  * @buffer_size.  @buffer may be NULL to request the size of the buffer
2430  * required.
2431  *
2432  * Return: Returns number of bytes used/required on success.
2433  */
2434 int security_inode_listsecurity(struct inode *inode,
2435 				char *buffer, size_t buffer_size)
2436 {
2437 	if (unlikely(IS_PRIVATE(inode)))
2438 		return 0;
2439 	return call_int_hook(inode_listsecurity, 0, inode, buffer, buffer_size);
2440 }
2441 EXPORT_SYMBOL(security_inode_listsecurity);
2442 
2443 /**
2444  * security_inode_getsecid() - Get an inode's secid
2445  * @inode: inode
2446  * @secid: secid to return
2447  *
2448  * Get the secid associated with the node.  In case of failure, @secid will be
2449  * set to zero.
2450  */
2451 void security_inode_getsecid(struct inode *inode, u32 *secid)
2452 {
2453 	call_void_hook(inode_getsecid, inode, secid);
2454 }
2455 
2456 /**
2457  * security_inode_copy_up() - Create new creds for an overlayfs copy-up op
2458  * @src: union dentry of copy-up file
2459  * @new: newly created creds
2460  *
2461  * A file is about to be copied up from lower layer to upper layer of overlay
2462  * filesystem. Security module can prepare a set of new creds and modify as
2463  * need be and return new creds. Caller will switch to new creds temporarily to
2464  * create new file and release newly allocated creds.
2465  *
2466  * Return: Returns 0 on success or a negative error code on error.
2467  */
2468 int security_inode_copy_up(struct dentry *src, struct cred **new)
2469 {
2470 	return call_int_hook(inode_copy_up, 0, src, new);
2471 }
2472 EXPORT_SYMBOL(security_inode_copy_up);
2473 
2474 /**
2475  * security_inode_copy_up_xattr() - Filter xattrs in an overlayfs copy-up op
2476  * @name: xattr name
2477  *
2478  * Filter the xattrs being copied up when a unioned file is copied up from a
2479  * lower layer to the union/overlay layer.   The caller is responsible for
2480  * reading and writing the xattrs, this hook is merely a filter.
2481  *
2482  * Return: Returns 0 to accept the xattr, 1 to discard the xattr, -EOPNOTSUPP
2483  *         if the security module does not know about attribute, or a negative
2484  *         error code to abort the copy up.
2485  */
2486 int security_inode_copy_up_xattr(const char *name)
2487 {
2488 	struct security_hook_list *hp;
2489 	int rc;
2490 
2491 	/*
2492 	 * The implementation can return 0 (accept the xattr), 1 (discard the
2493 	 * xattr), -EOPNOTSUPP if it does not know anything about the xattr or
2494 	 * any other error code in case of an error.
2495 	 */
2496 	hlist_for_each_entry(hp,
2497 			     &security_hook_heads.inode_copy_up_xattr, list) {
2498 		rc = hp->hook.inode_copy_up_xattr(name);
2499 		if (rc != LSM_RET_DEFAULT(inode_copy_up_xattr))
2500 			return rc;
2501 	}
2502 
2503 	return LSM_RET_DEFAULT(inode_copy_up_xattr);
2504 }
2505 EXPORT_SYMBOL(security_inode_copy_up_xattr);
2506 
2507 /**
2508  * security_kernfs_init_security() - Init LSM context for a kernfs node
2509  * @kn_dir: parent kernfs node
2510  * @kn: the kernfs node to initialize
2511  *
2512  * Initialize the security context of a newly created kernfs node based on its
2513  * own and its parent's attributes.
2514  *
2515  * Return: Returns 0 if permission is granted.
2516  */
2517 int security_kernfs_init_security(struct kernfs_node *kn_dir,
2518 				  struct kernfs_node *kn)
2519 {
2520 	return call_int_hook(kernfs_init_security, 0, kn_dir, kn);
2521 }
2522 
2523 /**
2524  * security_file_permission() - Check file permissions
2525  * @file: file
2526  * @mask: requested permissions
2527  *
2528  * Check file permissions before accessing an open file.  This hook is called
2529  * by various operations that read or write files.  A security module can use
2530  * this hook to perform additional checking on these operations, e.g. to
2531  * revalidate permissions on use to support privilege bracketing or policy
2532  * changes.  Notice that this hook is used when the actual read/write
2533  * operations are performed, whereas the inode_security_ops hook is called when
2534  * a file is opened (as well as many other operations).  Although this hook can
2535  * be used to revalidate permissions for various system call operations that
2536  * read or write files, it does not address the revalidation of permissions for
2537  * memory-mapped files.  Security modules must handle this separately if they
2538  * need such revalidation.
2539  *
2540  * Return: Returns 0 if permission is granted.
2541  */
2542 int security_file_permission(struct file *file, int mask)
2543 {
2544 	int ret;
2545 
2546 	ret = call_int_hook(file_permission, 0, file, mask);
2547 	if (ret)
2548 		return ret;
2549 
2550 	return fsnotify_perm(file, mask);
2551 }
2552 
2553 /**
2554  * security_file_alloc() - Allocate and init a file's LSM blob
2555  * @file: the file
2556  *
2557  * Allocate and attach a security structure to the file->f_security field.  The
2558  * security field is initialized to NULL when the structure is first created.
2559  *
2560  * Return: Return 0 if the hook is successful and permission is granted.
2561  */
2562 int security_file_alloc(struct file *file)
2563 {
2564 	int rc = lsm_file_alloc(file);
2565 
2566 	if (rc)
2567 		return rc;
2568 	rc = call_int_hook(file_alloc_security, 0, file);
2569 	if (unlikely(rc))
2570 		security_file_free(file);
2571 	return rc;
2572 }
2573 
2574 /**
2575  * security_file_free() - Free a file's LSM blob
2576  * @file: the file
2577  *
2578  * Deallocate and free any security structures stored in file->f_security.
2579  */
2580 void security_file_free(struct file *file)
2581 {
2582 	void *blob;
2583 
2584 	call_void_hook(file_free_security, file);
2585 
2586 	blob = file->f_security;
2587 	if (blob) {
2588 		file->f_security = NULL;
2589 		kmem_cache_free(lsm_file_cache, blob);
2590 	}
2591 }
2592 
2593 /**
2594  * security_file_ioctl() - Check if an ioctl is allowed
2595  * @file: associated file
2596  * @cmd: ioctl cmd
2597  * @arg: ioctl arguments
2598  *
2599  * Check permission for an ioctl operation on @file.  Note that @arg sometimes
2600  * represents a user space pointer; in other cases, it may be a simple integer
2601  * value.  When @arg represents a user space pointer, it should never be used
2602  * by the security module.
2603  *
2604  * Return: Returns 0 if permission is granted.
2605  */
2606 int security_file_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
2607 {
2608 	return call_int_hook(file_ioctl, 0, file, cmd, arg);
2609 }
2610 EXPORT_SYMBOL_GPL(security_file_ioctl);
2611 
2612 static inline unsigned long mmap_prot(struct file *file, unsigned long prot)
2613 {
2614 	/*
2615 	 * Does we have PROT_READ and does the application expect
2616 	 * it to imply PROT_EXEC?  If not, nothing to talk about...
2617 	 */
2618 	if ((prot & (PROT_READ | PROT_EXEC)) != PROT_READ)
2619 		return prot;
2620 	if (!(current->personality & READ_IMPLIES_EXEC))
2621 		return prot;
2622 	/*
2623 	 * if that's an anonymous mapping, let it.
2624 	 */
2625 	if (!file)
2626 		return prot | PROT_EXEC;
2627 	/*
2628 	 * ditto if it's not on noexec mount, except that on !MMU we need
2629 	 * NOMMU_MAP_EXEC (== VM_MAYEXEC) in this case
2630 	 */
2631 	if (!path_noexec(&file->f_path)) {
2632 #ifndef CONFIG_MMU
2633 		if (file->f_op->mmap_capabilities) {
2634 			unsigned caps = file->f_op->mmap_capabilities(file);
2635 			if (!(caps & NOMMU_MAP_EXEC))
2636 				return prot;
2637 		}
2638 #endif
2639 		return prot | PROT_EXEC;
2640 	}
2641 	/* anything on noexec mount won't get PROT_EXEC */
2642 	return prot;
2643 }
2644 
2645 /**
2646  * security_mmap_file() - Check if mmap'ing a file is allowed
2647  * @file: file
2648  * @prot: protection applied by the kernel
2649  * @flags: flags
2650  *
2651  * Check permissions for a mmap operation.  The @file may be NULL, e.g. if
2652  * mapping anonymous memory.
2653  *
2654  * Return: Returns 0 if permission is granted.
2655  */
2656 int security_mmap_file(struct file *file, unsigned long prot,
2657 		       unsigned long flags)
2658 {
2659 	unsigned long prot_adj = mmap_prot(file, prot);
2660 	int ret;
2661 
2662 	ret = call_int_hook(mmap_file, 0, file, prot, prot_adj, flags);
2663 	if (ret)
2664 		return ret;
2665 	return ima_file_mmap(file, prot, prot_adj, flags);
2666 }
2667 
2668 /**
2669  * security_mmap_addr() - Check if mmap'ing an address is allowed
2670  * @addr: address
2671  *
2672  * Check permissions for a mmap operation at @addr.
2673  *
2674  * Return: Returns 0 if permission is granted.
2675  */
2676 int security_mmap_addr(unsigned long addr)
2677 {
2678 	return call_int_hook(mmap_addr, 0, addr);
2679 }
2680 
2681 /**
2682  * security_file_mprotect() - Check if changing memory protections is allowed
2683  * @vma: memory region
2684  * @reqprot: application requested protection
2685  * @prot: protection applied by the kernel
2686  *
2687  * Check permissions before changing memory access permissions.
2688  *
2689  * Return: Returns 0 if permission is granted.
2690  */
2691 int security_file_mprotect(struct vm_area_struct *vma, unsigned long reqprot,
2692 			   unsigned long prot)
2693 {
2694 	int ret;
2695 
2696 	ret = call_int_hook(file_mprotect, 0, vma, reqprot, prot);
2697 	if (ret)
2698 		return ret;
2699 	return ima_file_mprotect(vma, prot);
2700 }
2701 
2702 /**
2703  * security_file_lock() - Check if a file lock is allowed
2704  * @file: file
2705  * @cmd: lock operation (e.g. F_RDLCK, F_WRLCK)
2706  *
2707  * Check permission before performing file locking operations.  Note the hook
2708  * mediates both flock and fcntl style locks.
2709  *
2710  * Return: Returns 0 if permission is granted.
2711  */
2712 int security_file_lock(struct file *file, unsigned int cmd)
2713 {
2714 	return call_int_hook(file_lock, 0, file, cmd);
2715 }
2716 
2717 /**
2718  * security_file_fcntl() - Check if fcntl() op is allowed
2719  * @file: file
2720  * @cmd: fnctl command
2721  * @arg: command argument
2722  *
2723  * Check permission before allowing the file operation specified by @cmd from
2724  * being performed on the file @file.  Note that @arg sometimes represents a
2725  * user space pointer; in other cases, it may be a simple integer value.  When
2726  * @arg represents a user space pointer, it should never be used by the
2727  * security module.
2728  *
2729  * Return: Returns 0 if permission is granted.
2730  */
2731 int security_file_fcntl(struct file *file, unsigned int cmd, unsigned long arg)
2732 {
2733 	return call_int_hook(file_fcntl, 0, file, cmd, arg);
2734 }
2735 
2736 /**
2737  * security_file_set_fowner() - Set the file owner info in the LSM blob
2738  * @file: the file
2739  *
2740  * Save owner security information (typically from current->security) in
2741  * file->f_security for later use by the send_sigiotask hook.
2742  *
2743  * Return: Returns 0 on success.
2744  */
2745 void security_file_set_fowner(struct file *file)
2746 {
2747 	call_void_hook(file_set_fowner, file);
2748 }
2749 
2750 /**
2751  * security_file_send_sigiotask() - Check if sending SIGIO/SIGURG is allowed
2752  * @tsk: target task
2753  * @fown: signal sender
2754  * @sig: signal to be sent, SIGIO is sent if 0
2755  *
2756  * Check permission for the file owner @fown to send SIGIO or SIGURG to the
2757  * process @tsk.  Note that this hook is sometimes called from interrupt.  Note
2758  * that the fown_struct, @fown, is never outside the context of a struct file,
2759  * so the file structure (and associated security information) can always be
2760  * obtained: container_of(fown, struct file, f_owner).
2761  *
2762  * Return: Returns 0 if permission is granted.
2763  */
2764 int security_file_send_sigiotask(struct task_struct *tsk,
2765 				 struct fown_struct *fown, int sig)
2766 {
2767 	return call_int_hook(file_send_sigiotask, 0, tsk, fown, sig);
2768 }
2769 
2770 /**
2771  * security_file_receive() - Check is receiving a file via IPC is allowed
2772  * @file: file being received
2773  *
2774  * This hook allows security modules to control the ability of a process to
2775  * receive an open file descriptor via socket IPC.
2776  *
2777  * Return: Returns 0 if permission is granted.
2778  */
2779 int security_file_receive(struct file *file)
2780 {
2781 	return call_int_hook(file_receive, 0, file);
2782 }
2783 
2784 /**
2785  * security_file_open() - Save open() time state for late use by the LSM
2786  * @file:
2787  *
2788  * Save open-time permission checking state for later use upon file_permission,
2789  * and recheck access if anything has changed since inode_permission.
2790  *
2791  * Return: Returns 0 if permission is granted.
2792  */
2793 int security_file_open(struct file *file)
2794 {
2795 	int ret;
2796 
2797 	ret = call_int_hook(file_open, 0, file);
2798 	if (ret)
2799 		return ret;
2800 
2801 	return fsnotify_perm(file, MAY_OPEN);
2802 }
2803 
2804 /**
2805  * security_file_truncate() - Check if truncating a file is allowed
2806  * @file: file
2807  *
2808  * Check permission before truncating a file, i.e. using ftruncate.  Note that
2809  * truncation permission may also be checked based on the path, using the
2810  * @path_truncate hook.
2811  *
2812  * Return: Returns 0 if permission is granted.
2813  */
2814 int security_file_truncate(struct file *file)
2815 {
2816 	return call_int_hook(file_truncate, 0, file);
2817 }
2818 
2819 /**
2820  * security_task_alloc() - Allocate a task's LSM blob
2821  * @task: the task
2822  * @clone_flags: flags indicating what is being shared
2823  *
2824  * Handle allocation of task-related resources.
2825  *
2826  * Return: Returns a zero on success, negative values on failure.
2827  */
2828 int security_task_alloc(struct task_struct *task, unsigned long clone_flags)
2829 {
2830 	int rc = lsm_task_alloc(task);
2831 
2832 	if (rc)
2833 		return rc;
2834 	rc = call_int_hook(task_alloc, 0, task, clone_flags);
2835 	if (unlikely(rc))
2836 		security_task_free(task);
2837 	return rc;
2838 }
2839 
2840 /**
2841  * security_task_free() - Free a task's LSM blob and related resources
2842  * @task: task
2843  *
2844  * Handle release of task-related resources.  Note that this can be called from
2845  * interrupt context.
2846  */
2847 void security_task_free(struct task_struct *task)
2848 {
2849 	call_void_hook(task_free, task);
2850 
2851 	kfree(task->security);
2852 	task->security = NULL;
2853 }
2854 
2855 /**
2856  * security_cred_alloc_blank() - Allocate the min memory to allow cred_transfer
2857  * @cred: credentials
2858  * @gfp: gfp flags
2859  *
2860  * Only allocate sufficient memory and attach to @cred such that
2861  * cred_transfer() will not get ENOMEM.
2862  *
2863  * Return: Returns 0 on success, negative values on failure.
2864  */
2865 int security_cred_alloc_blank(struct cred *cred, gfp_t gfp)
2866 {
2867 	int rc = lsm_cred_alloc(cred, gfp);
2868 
2869 	if (rc)
2870 		return rc;
2871 
2872 	rc = call_int_hook(cred_alloc_blank, 0, cred, gfp);
2873 	if (unlikely(rc))
2874 		security_cred_free(cred);
2875 	return rc;
2876 }
2877 
2878 /**
2879  * security_cred_free() - Free the cred's LSM blob and associated resources
2880  * @cred: credentials
2881  *
2882  * Deallocate and clear the cred->security field in a set of credentials.
2883  */
2884 void security_cred_free(struct cred *cred)
2885 {
2886 	/*
2887 	 * There is a failure case in prepare_creds() that
2888 	 * may result in a call here with ->security being NULL.
2889 	 */
2890 	if (unlikely(cred->security == NULL))
2891 		return;
2892 
2893 	call_void_hook(cred_free, cred);
2894 
2895 	kfree(cred->security);
2896 	cred->security = NULL;
2897 }
2898 
2899 /**
2900  * security_prepare_creds() - Prepare a new set of credentials
2901  * @new: new credentials
2902  * @old: original credentials
2903  * @gfp: gfp flags
2904  *
2905  * Prepare a new set of credentials by copying the data from the old set.
2906  *
2907  * Return: Returns 0 on success, negative values on failure.
2908  */
2909 int security_prepare_creds(struct cred *new, const struct cred *old, gfp_t gfp)
2910 {
2911 	int rc = lsm_cred_alloc(new, gfp);
2912 
2913 	if (rc)
2914 		return rc;
2915 
2916 	rc = call_int_hook(cred_prepare, 0, new, old, gfp);
2917 	if (unlikely(rc))
2918 		security_cred_free(new);
2919 	return rc;
2920 }
2921 
2922 /**
2923  * security_transfer_creds() - Transfer creds
2924  * @new: target credentials
2925  * @old: original credentials
2926  *
2927  * Transfer data from original creds to new creds.
2928  */
2929 void security_transfer_creds(struct cred *new, const struct cred *old)
2930 {
2931 	call_void_hook(cred_transfer, new, old);
2932 }
2933 
2934 /**
2935  * security_cred_getsecid() - Get the secid from a set of credentials
2936  * @c: credentials
2937  * @secid: secid value
2938  *
2939  * Retrieve the security identifier of the cred structure @c.  In case of
2940  * failure, @secid will be set to zero.
2941  */
2942 void security_cred_getsecid(const struct cred *c, u32 *secid)
2943 {
2944 	*secid = 0;
2945 	call_void_hook(cred_getsecid, c, secid);
2946 }
2947 EXPORT_SYMBOL(security_cred_getsecid);
2948 
2949 /**
2950  * security_kernel_act_as() - Set the kernel credentials to act as secid
2951  * @new: credentials
2952  * @secid: secid
2953  *
2954  * Set the credentials for a kernel service to act as (subjective context).
2955  * The current task must be the one that nominated @secid.
2956  *
2957  * Return: Returns 0 if successful.
2958  */
2959 int security_kernel_act_as(struct cred *new, u32 secid)
2960 {
2961 	return call_int_hook(kernel_act_as, 0, new, secid);
2962 }
2963 
2964 /**
2965  * security_kernel_create_files_as() - Set file creation context using an inode
2966  * @new: target credentials
2967  * @inode: reference inode
2968  *
2969  * Set the file creation context in a set of credentials to be the same as the
2970  * objective context of the specified inode.  The current task must be the one
2971  * that nominated @inode.
2972  *
2973  * Return: Returns 0 if successful.
2974  */
2975 int security_kernel_create_files_as(struct cred *new, struct inode *inode)
2976 {
2977 	return call_int_hook(kernel_create_files_as, 0, new, inode);
2978 }
2979 
2980 /**
2981  * security_kernel_module_request() - Check is loading a module is allowed
2982  * @kmod_name: module name
2983  *
2984  * Ability to trigger the kernel to automatically upcall to userspace for
2985  * userspace to load a kernel module with the given name.
2986  *
2987  * Return: Returns 0 if successful.
2988  */
2989 int security_kernel_module_request(char *kmod_name)
2990 {
2991 	int ret;
2992 
2993 	ret = call_int_hook(kernel_module_request, 0, kmod_name);
2994 	if (ret)
2995 		return ret;
2996 	return integrity_kernel_module_request(kmod_name);
2997 }
2998 
2999 /**
3000  * security_kernel_read_file() - Read a file specified by userspace
3001  * @file: file
3002  * @id: file identifier
3003  * @contents: trust if security_kernel_post_read_file() will be called
3004  *
3005  * Read a file specified by userspace.
3006  *
3007  * Return: Returns 0 if permission is granted.
3008  */
3009 int security_kernel_read_file(struct file *file, enum kernel_read_file_id id,
3010 			      bool contents)
3011 {
3012 	int ret;
3013 
3014 	ret = call_int_hook(kernel_read_file, 0, file, id, contents);
3015 	if (ret)
3016 		return ret;
3017 	return ima_read_file(file, id, contents);
3018 }
3019 EXPORT_SYMBOL_GPL(security_kernel_read_file);
3020 
3021 /**
3022  * security_kernel_post_read_file() - Read a file specified by userspace
3023  * @file: file
3024  * @buf: file contents
3025  * @size: size of file contents
3026  * @id: file identifier
3027  *
3028  * Read a file specified by userspace.  This must be paired with a prior call
3029  * to security_kernel_read_file() call that indicated this hook would also be
3030  * called, see security_kernel_read_file() for more information.
3031  *
3032  * Return: Returns 0 if permission is granted.
3033  */
3034 int security_kernel_post_read_file(struct file *file, char *buf, loff_t size,
3035 				   enum kernel_read_file_id id)
3036 {
3037 	int ret;
3038 
3039 	ret = call_int_hook(kernel_post_read_file, 0, file, buf, size, id);
3040 	if (ret)
3041 		return ret;
3042 	return ima_post_read_file(file, buf, size, id);
3043 }
3044 EXPORT_SYMBOL_GPL(security_kernel_post_read_file);
3045 
3046 /**
3047  * security_kernel_load_data() - Load data provided by userspace
3048  * @id: data identifier
3049  * @contents: true if security_kernel_post_load_data() will be called
3050  *
3051  * Load data provided by userspace.
3052  *
3053  * Return: Returns 0 if permission is granted.
3054  */
3055 int security_kernel_load_data(enum kernel_load_data_id id, bool contents)
3056 {
3057 	int ret;
3058 
3059 	ret = call_int_hook(kernel_load_data, 0, id, contents);
3060 	if (ret)
3061 		return ret;
3062 	return ima_load_data(id, contents);
3063 }
3064 EXPORT_SYMBOL_GPL(security_kernel_load_data);
3065 
3066 /**
3067  * security_kernel_post_load_data() - Load userspace data from a non-file source
3068  * @buf: data
3069  * @size: size of data
3070  * @id: data identifier
3071  * @description: text description of data, specific to the id value
3072  *
3073  * Load data provided by a non-file source (usually userspace buffer).  This
3074  * must be paired with a prior security_kernel_load_data() call that indicated
3075  * this hook would also be called, see security_kernel_load_data() for more
3076  * information.
3077  *
3078  * Return: Returns 0 if permission is granted.
3079  */
3080 int security_kernel_post_load_data(char *buf, loff_t size,
3081 				   enum kernel_load_data_id id,
3082 				   char *description)
3083 {
3084 	int ret;
3085 
3086 	ret = call_int_hook(kernel_post_load_data, 0, buf, size, id,
3087 			    description);
3088 	if (ret)
3089 		return ret;
3090 	return ima_post_load_data(buf, size, id, description);
3091 }
3092 EXPORT_SYMBOL_GPL(security_kernel_post_load_data);
3093 
3094 /**
3095  * security_task_fix_setuid() - Update LSM with new user id attributes
3096  * @new: updated credentials
3097  * @old: credentials being replaced
3098  * @flags: LSM_SETID_* flag values
3099  *
3100  * Update the module's state after setting one or more of the user identity
3101  * attributes of the current process.  The @flags parameter indicates which of
3102  * the set*uid system calls invoked this hook.  If @new is the set of
3103  * credentials that will be installed.  Modifications should be made to this
3104  * rather than to @current->cred.
3105  *
3106  * Return: Returns 0 on success.
3107  */
3108 int security_task_fix_setuid(struct cred *new, const struct cred *old,
3109 			     int flags)
3110 {
3111 	return call_int_hook(task_fix_setuid, 0, new, old, flags);
3112 }
3113 
3114 /**
3115  * security_task_fix_setgid() - Update LSM with new group id attributes
3116  * @new: updated credentials
3117  * @old: credentials being replaced
3118  * @flags: LSM_SETID_* flag value
3119  *
3120  * Update the module's state after setting one or more of the group identity
3121  * attributes of the current process.  The @flags parameter indicates which of
3122  * the set*gid system calls invoked this hook.  @new is the set of credentials
3123  * that will be installed.  Modifications should be made to this rather than to
3124  * @current->cred.
3125  *
3126  * Return: Returns 0 on success.
3127  */
3128 int security_task_fix_setgid(struct cred *new, const struct cred *old,
3129 			     int flags)
3130 {
3131 	return call_int_hook(task_fix_setgid, 0, new, old, flags);
3132 }
3133 
3134 /**
3135  * security_task_fix_setgroups() - Update LSM with new supplementary groups
3136  * @new: updated credentials
3137  * @old: credentials being replaced
3138  *
3139  * Update the module's state after setting the supplementary group identity
3140  * attributes of the current process.  @new is the set of credentials that will
3141  * be installed.  Modifications should be made to this rather than to
3142  * @current->cred.
3143  *
3144  * Return: Returns 0 on success.
3145  */
3146 int security_task_fix_setgroups(struct cred *new, const struct cred *old)
3147 {
3148 	return call_int_hook(task_fix_setgroups, 0, new, old);
3149 }
3150 
3151 /**
3152  * security_task_setpgid() - Check if setting the pgid is allowed
3153  * @p: task being modified
3154  * @pgid: new pgid
3155  *
3156  * Check permission before setting the process group identifier of the process
3157  * @p to @pgid.
3158  *
3159  * Return: Returns 0 if permission is granted.
3160  */
3161 int security_task_setpgid(struct task_struct *p, pid_t pgid)
3162 {
3163 	return call_int_hook(task_setpgid, 0, p, pgid);
3164 }
3165 
3166 /**
3167  * security_task_getpgid() - Check if getting the pgid is allowed
3168  * @p: task
3169  *
3170  * Check permission before getting the process group identifier of the process
3171  * @p.
3172  *
3173  * Return: Returns 0 if permission is granted.
3174  */
3175 int security_task_getpgid(struct task_struct *p)
3176 {
3177 	return call_int_hook(task_getpgid, 0, p);
3178 }
3179 
3180 /**
3181  * security_task_getsid() - Check if getting the session id is allowed
3182  * @p: task
3183  *
3184  * Check permission before getting the session identifier of the process @p.
3185  *
3186  * Return: Returns 0 if permission is granted.
3187  */
3188 int security_task_getsid(struct task_struct *p)
3189 {
3190 	return call_int_hook(task_getsid, 0, p);
3191 }
3192 
3193 /**
3194  * security_current_getsecid_subj() - Get the current task's subjective secid
3195  * @secid: secid value
3196  *
3197  * Retrieve the subjective security identifier of the current task and return
3198  * it in @secid.  In case of failure, @secid will be set to zero.
3199  */
3200 void security_current_getsecid_subj(u32 *secid)
3201 {
3202 	*secid = 0;
3203 	call_void_hook(current_getsecid_subj, secid);
3204 }
3205 EXPORT_SYMBOL(security_current_getsecid_subj);
3206 
3207 /**
3208  * security_task_getsecid_obj() - Get a task's objective secid
3209  * @p: target task
3210  * @secid: secid value
3211  *
3212  * Retrieve the objective security identifier of the task_struct in @p and
3213  * return it in @secid. In case of failure, @secid will be set to zero.
3214  */
3215 void security_task_getsecid_obj(struct task_struct *p, u32 *secid)
3216 {
3217 	*secid = 0;
3218 	call_void_hook(task_getsecid_obj, p, secid);
3219 }
3220 EXPORT_SYMBOL(security_task_getsecid_obj);
3221 
3222 /**
3223  * security_task_setnice() - Check if setting a task's nice value is allowed
3224  * @p: target task
3225  * @nice: nice value
3226  *
3227  * Check permission before setting the nice value of @p to @nice.
3228  *
3229  * Return: Returns 0 if permission is granted.
3230  */
3231 int security_task_setnice(struct task_struct *p, int nice)
3232 {
3233 	return call_int_hook(task_setnice, 0, p, nice);
3234 }
3235 
3236 /**
3237  * security_task_setioprio() - Check if setting a task's ioprio is allowed
3238  * @p: target task
3239  * @ioprio: ioprio value
3240  *
3241  * Check permission before setting the ioprio value of @p to @ioprio.
3242  *
3243  * Return: Returns 0 if permission is granted.
3244  */
3245 int security_task_setioprio(struct task_struct *p, int ioprio)
3246 {
3247 	return call_int_hook(task_setioprio, 0, p, ioprio);
3248 }
3249 
3250 /**
3251  * security_task_getioprio() - Check if getting a task's ioprio is allowed
3252  * @p: task
3253  *
3254  * Check permission before getting the ioprio value of @p.
3255  *
3256  * Return: Returns 0 if permission is granted.
3257  */
3258 int security_task_getioprio(struct task_struct *p)
3259 {
3260 	return call_int_hook(task_getioprio, 0, p);
3261 }
3262 
3263 /**
3264  * security_task_prlimit() - Check if get/setting resources limits is allowed
3265  * @cred: current task credentials
3266  * @tcred: target task credentials
3267  * @flags: LSM_PRLIMIT_* flag bits indicating a get/set/both
3268  *
3269  * Check permission before getting and/or setting the resource limits of
3270  * another task.
3271  *
3272  * Return: Returns 0 if permission is granted.
3273  */
3274 int security_task_prlimit(const struct cred *cred, const struct cred *tcred,
3275 			  unsigned int flags)
3276 {
3277 	return call_int_hook(task_prlimit, 0, cred, tcred, flags);
3278 }
3279 
3280 /**
3281  * security_task_setrlimit() - Check if setting a new rlimit value is allowed
3282  * @p: target task's group leader
3283  * @resource: resource whose limit is being set
3284  * @new_rlim: new resource limit
3285  *
3286  * Check permission before setting the resource limits of process @p for
3287  * @resource to @new_rlim.  The old resource limit values can be examined by
3288  * dereferencing (p->signal->rlim + resource).
3289  *
3290  * Return: Returns 0 if permission is granted.
3291  */
3292 int security_task_setrlimit(struct task_struct *p, unsigned int resource,
3293 			    struct rlimit *new_rlim)
3294 {
3295 	return call_int_hook(task_setrlimit, 0, p, resource, new_rlim);
3296 }
3297 
3298 /**
3299  * security_task_setscheduler() - Check if setting sched policy/param is allowed
3300  * @p: target task
3301  *
3302  * Check permission before setting scheduling policy and/or parameters of
3303  * process @p.
3304  *
3305  * Return: Returns 0 if permission is granted.
3306  */
3307 int security_task_setscheduler(struct task_struct *p)
3308 {
3309 	return call_int_hook(task_setscheduler, 0, p);
3310 }
3311 
3312 /**
3313  * security_task_getscheduler() - Check if getting scheduling info is allowed
3314  * @p: target task
3315  *
3316  * Check permission before obtaining scheduling information for process @p.
3317  *
3318  * Return: Returns 0 if permission is granted.
3319  */
3320 int security_task_getscheduler(struct task_struct *p)
3321 {
3322 	return call_int_hook(task_getscheduler, 0, p);
3323 }
3324 
3325 /**
3326  * security_task_movememory() - Check if moving memory is allowed
3327  * @p: task
3328  *
3329  * Check permission before moving memory owned by process @p.
3330  *
3331  * Return: Returns 0 if permission is granted.
3332  */
3333 int security_task_movememory(struct task_struct *p)
3334 {
3335 	return call_int_hook(task_movememory, 0, p);
3336 }
3337 
3338 /**
3339  * security_task_kill() - Check if sending a signal is allowed
3340  * @p: target process
3341  * @info: signal information
3342  * @sig: signal value
3343  * @cred: credentials of the signal sender, NULL if @current
3344  *
3345  * Check permission before sending signal @sig to @p.  @info can be NULL, the
3346  * constant 1, or a pointer to a kernel_siginfo structure.  If @info is 1 or
3347  * SI_FROMKERNEL(info) is true, then the signal should be viewed as coming from
3348  * the kernel and should typically be permitted.  SIGIO signals are handled
3349  * separately by the send_sigiotask hook in file_security_ops.
3350  *
3351  * Return: Returns 0 if permission is granted.
3352  */
3353 int security_task_kill(struct task_struct *p, struct kernel_siginfo *info,
3354 		       int sig, const struct cred *cred)
3355 {
3356 	return call_int_hook(task_kill, 0, p, info, sig, cred);
3357 }
3358 
3359 /**
3360  * security_task_prctl() - Check if a prctl op is allowed
3361  * @option: operation
3362  * @arg2: argument
3363  * @arg3: argument
3364  * @arg4: argument
3365  * @arg5: argument
3366  *
3367  * Check permission before performing a process control operation on the
3368  * current process.
3369  *
3370  * Return: Return -ENOSYS if no-one wanted to handle this op, any other value
3371  *         to cause prctl() to return immediately with that value.
3372  */
3373 int security_task_prctl(int option, unsigned long arg2, unsigned long arg3,
3374 			unsigned long arg4, unsigned long arg5)
3375 {
3376 	int thisrc;
3377 	int rc = LSM_RET_DEFAULT(task_prctl);
3378 	struct security_hook_list *hp;
3379 
3380 	hlist_for_each_entry(hp, &security_hook_heads.task_prctl, list) {
3381 		thisrc = hp->hook.task_prctl(option, arg2, arg3, arg4, arg5);
3382 		if (thisrc != LSM_RET_DEFAULT(task_prctl)) {
3383 			rc = thisrc;
3384 			if (thisrc != 0)
3385 				break;
3386 		}
3387 	}
3388 	return rc;
3389 }
3390 
3391 /**
3392  * security_task_to_inode() - Set the security attributes of a task's inode
3393  * @p: task
3394  * @inode: inode
3395  *
3396  * Set the security attributes for an inode based on an associated task's
3397  * security attributes, e.g. for /proc/pid inodes.
3398  */
3399 void security_task_to_inode(struct task_struct *p, struct inode *inode)
3400 {
3401 	call_void_hook(task_to_inode, p, inode);
3402 }
3403 
3404 /**
3405  * security_create_user_ns() - Check if creating a new userns is allowed
3406  * @cred: prepared creds
3407  *
3408  * Check permission prior to creating a new user namespace.
3409  *
3410  * Return: Returns 0 if successful, otherwise < 0 error code.
3411  */
3412 int security_create_user_ns(const struct cred *cred)
3413 {
3414 	return call_int_hook(userns_create, 0, cred);
3415 }
3416 
3417 /**
3418  * security_ipc_permission() - Check if sysv ipc access is allowed
3419  * @ipcp: ipc permission structure
3420  * @flag: requested permissions
3421  *
3422  * Check permissions for access to IPC.
3423  *
3424  * Return: Returns 0 if permission is granted.
3425  */
3426 int security_ipc_permission(struct kern_ipc_perm *ipcp, short flag)
3427 {
3428 	return call_int_hook(ipc_permission, 0, ipcp, flag);
3429 }
3430 
3431 /**
3432  * security_ipc_getsecid() - Get the sysv ipc object's secid
3433  * @ipcp: ipc permission structure
3434  * @secid: secid pointer
3435  *
3436  * Get the secid associated with the ipc object.  In case of failure, @secid
3437  * will be set to zero.
3438  */
3439 void security_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid)
3440 {
3441 	*secid = 0;
3442 	call_void_hook(ipc_getsecid, ipcp, secid);
3443 }
3444 
3445 /**
3446  * security_msg_msg_alloc() - Allocate a sysv ipc message LSM blob
3447  * @msg: message structure
3448  *
3449  * Allocate and attach a security structure to the msg->security field.  The
3450  * security field is initialized to NULL when the structure is first created.
3451  *
3452  * Return: Return 0 if operation was successful and permission is granted.
3453  */
3454 int security_msg_msg_alloc(struct msg_msg *msg)
3455 {
3456 	int rc = lsm_msg_msg_alloc(msg);
3457 
3458 	if (unlikely(rc))
3459 		return rc;
3460 	rc = call_int_hook(msg_msg_alloc_security, 0, msg);
3461 	if (unlikely(rc))
3462 		security_msg_msg_free(msg);
3463 	return rc;
3464 }
3465 
3466 /**
3467  * security_msg_msg_free() - Free a sysv ipc message LSM blob
3468  * @msg: message structure
3469  *
3470  * Deallocate the security structure for this message.
3471  */
3472 void security_msg_msg_free(struct msg_msg *msg)
3473 {
3474 	call_void_hook(msg_msg_free_security, msg);
3475 	kfree(msg->security);
3476 	msg->security = NULL;
3477 }
3478 
3479 /**
3480  * security_msg_queue_alloc() - Allocate a sysv ipc msg queue LSM blob
3481  * @msq: sysv ipc permission structure
3482  *
3483  * Allocate and attach a security structure to @msg. The security field is
3484  * initialized to NULL when the structure is first created.
3485  *
3486  * Return: Returns 0 if operation was successful and permission is granted.
3487  */
3488 int security_msg_queue_alloc(struct kern_ipc_perm *msq)
3489 {
3490 	int rc = lsm_ipc_alloc(msq);
3491 
3492 	if (unlikely(rc))
3493 		return rc;
3494 	rc = call_int_hook(msg_queue_alloc_security, 0, msq);
3495 	if (unlikely(rc))
3496 		security_msg_queue_free(msq);
3497 	return rc;
3498 }
3499 
3500 /**
3501  * security_msg_queue_free() - Free a sysv ipc msg queue LSM blob
3502  * @msq: sysv ipc permission structure
3503  *
3504  * Deallocate security field @perm->security for the message queue.
3505  */
3506 void security_msg_queue_free(struct kern_ipc_perm *msq)
3507 {
3508 	call_void_hook(msg_queue_free_security, msq);
3509 	kfree(msq->security);
3510 	msq->security = NULL;
3511 }
3512 
3513 /**
3514  * security_msg_queue_associate() - Check if a msg queue operation is allowed
3515  * @msq: sysv ipc permission structure
3516  * @msqflg: operation flags
3517  *
3518  * Check permission when a message queue is requested through the msgget system
3519  * call. This hook is only called when returning the message queue identifier
3520  * for an existing message queue, not when a new message queue is created.
3521  *
3522  * Return: Return 0 if permission is granted.
3523  */
3524 int security_msg_queue_associate(struct kern_ipc_perm *msq, int msqflg)
3525 {
3526 	return call_int_hook(msg_queue_associate, 0, msq, msqflg);
3527 }
3528 
3529 /**
3530  * security_msg_queue_msgctl() - Check if a msg queue operation is allowed
3531  * @msq: sysv ipc permission structure
3532  * @cmd: operation
3533  *
3534  * Check permission when a message control operation specified by @cmd is to be
3535  * performed on the message queue with permissions.
3536  *
3537  * Return: Returns 0 if permission is granted.
3538  */
3539 int security_msg_queue_msgctl(struct kern_ipc_perm *msq, int cmd)
3540 {
3541 	return call_int_hook(msg_queue_msgctl, 0, msq, cmd);
3542 }
3543 
3544 /**
3545  * security_msg_queue_msgsnd() - Check if sending a sysv ipc message is allowed
3546  * @msq: sysv ipc permission structure
3547  * @msg: message
3548  * @msqflg: operation flags
3549  *
3550  * Check permission before a message, @msg, is enqueued on the message queue
3551  * with permissions specified in @msq.
3552  *
3553  * Return: Returns 0 if permission is granted.
3554  */
3555 int security_msg_queue_msgsnd(struct kern_ipc_perm *msq,
3556 			      struct msg_msg *msg, int msqflg)
3557 {
3558 	return call_int_hook(msg_queue_msgsnd, 0, msq, msg, msqflg);
3559 }
3560 
3561 /**
3562  * security_msg_queue_msgrcv() - Check if receiving a sysv ipc msg is allowed
3563  * @msq: sysv ipc permission structure
3564  * @msg: message
3565  * @target: target task
3566  * @type: type of message requested
3567  * @mode: operation flags
3568  *
3569  * Check permission before a message, @msg, is removed from the message	queue.
3570  * The @target task structure contains a pointer to the process that will be
3571  * receiving the message (not equal to the current process when inline receives
3572  * are being performed).
3573  *
3574  * Return: Returns 0 if permission is granted.
3575  */
3576 int security_msg_queue_msgrcv(struct kern_ipc_perm *msq, struct msg_msg *msg,
3577 			      struct task_struct *target, long type, int mode)
3578 {
3579 	return call_int_hook(msg_queue_msgrcv, 0, msq, msg, target, type, mode);
3580 }
3581 
3582 /**
3583  * security_shm_alloc() - Allocate a sysv shm LSM blob
3584  * @shp: sysv ipc permission structure
3585  *
3586  * Allocate and attach a security structure to the @shp security field.  The
3587  * security field is initialized to NULL when the structure is first created.
3588  *
3589  * Return: Returns 0 if operation was successful and permission is granted.
3590  */
3591 int security_shm_alloc(struct kern_ipc_perm *shp)
3592 {
3593 	int rc = lsm_ipc_alloc(shp);
3594 
3595 	if (unlikely(rc))
3596 		return rc;
3597 	rc = call_int_hook(shm_alloc_security, 0, shp);
3598 	if (unlikely(rc))
3599 		security_shm_free(shp);
3600 	return rc;
3601 }
3602 
3603 /**
3604  * security_shm_free() - Free a sysv shm LSM blob
3605  * @shp: sysv ipc permission structure
3606  *
3607  * Deallocate the security structure @perm->security for the memory segment.
3608  */
3609 void security_shm_free(struct kern_ipc_perm *shp)
3610 {
3611 	call_void_hook(shm_free_security, shp);
3612 	kfree(shp->security);
3613 	shp->security = NULL;
3614 }
3615 
3616 /**
3617  * security_shm_associate() - Check if a sysv shm operation is allowed
3618  * @shp: sysv ipc permission structure
3619  * @shmflg: operation flags
3620  *
3621  * Check permission when a shared memory region is requested through the shmget
3622  * system call. This hook is only called when returning the shared memory
3623  * region identifier for an existing region, not when a new shared memory
3624  * region is created.
3625  *
3626  * Return: Returns 0 if permission is granted.
3627  */
3628 int security_shm_associate(struct kern_ipc_perm *shp, int shmflg)
3629 {
3630 	return call_int_hook(shm_associate, 0, shp, shmflg);
3631 }
3632 
3633 /**
3634  * security_shm_shmctl() - Check if a sysv shm operation is allowed
3635  * @shp: sysv ipc permission structure
3636  * @cmd: operation
3637  *
3638  * Check permission when a shared memory control operation specified by @cmd is
3639  * to be performed on the shared memory region with permissions in @shp.
3640  *
3641  * Return: Return 0 if permission is granted.
3642  */
3643 int security_shm_shmctl(struct kern_ipc_perm *shp, int cmd)
3644 {
3645 	return call_int_hook(shm_shmctl, 0, shp, cmd);
3646 }
3647 
3648 /**
3649  * security_shm_shmat() - Check if a sysv shm attach operation is allowed
3650  * @shp: sysv ipc permission structure
3651  * @shmaddr: address of memory region to attach
3652  * @shmflg: operation flags
3653  *
3654  * Check permissions prior to allowing the shmat system call to attach the
3655  * shared memory segment with permissions @shp to the data segment of the
3656  * calling process. The attaching address is specified by @shmaddr.
3657  *
3658  * Return: Returns 0 if permission is granted.
3659  */
3660 int security_shm_shmat(struct kern_ipc_perm *shp,
3661 		       char __user *shmaddr, int shmflg)
3662 {
3663 	return call_int_hook(shm_shmat, 0, shp, shmaddr, shmflg);
3664 }
3665 
3666 /**
3667  * security_sem_alloc() - Allocate a sysv semaphore LSM blob
3668  * @sma: sysv ipc permission structure
3669  *
3670  * Allocate and attach a security structure to the @sma security field. The
3671  * security field is initialized to NULL when the structure is first created.
3672  *
3673  * Return: Returns 0 if operation was successful and permission is granted.
3674  */
3675 int security_sem_alloc(struct kern_ipc_perm *sma)
3676 {
3677 	int rc = lsm_ipc_alloc(sma);
3678 
3679 	if (unlikely(rc))
3680 		return rc;
3681 	rc = call_int_hook(sem_alloc_security, 0, sma);
3682 	if (unlikely(rc))
3683 		security_sem_free(sma);
3684 	return rc;
3685 }
3686 
3687 /**
3688  * security_sem_free() - Free a sysv semaphore LSM blob
3689  * @sma: sysv ipc permission structure
3690  *
3691  * Deallocate security structure @sma->security for the semaphore.
3692  */
3693 void security_sem_free(struct kern_ipc_perm *sma)
3694 {
3695 	call_void_hook(sem_free_security, sma);
3696 	kfree(sma->security);
3697 	sma->security = NULL;
3698 }
3699 
3700 /**
3701  * security_sem_associate() - Check if a sysv semaphore operation is allowed
3702  * @sma: sysv ipc permission structure
3703  * @semflg: operation flags
3704  *
3705  * Check permission when a semaphore is requested through the semget system
3706  * call. This hook is only called when returning the semaphore identifier for
3707  * an existing semaphore, not when a new one must be created.
3708  *
3709  * Return: Returns 0 if permission is granted.
3710  */
3711 int security_sem_associate(struct kern_ipc_perm *sma, int semflg)
3712 {
3713 	return call_int_hook(sem_associate, 0, sma, semflg);
3714 }
3715 
3716 /**
3717  * security_sem_semctl() - Check if a sysv semaphore operation is allowed
3718  * @sma: sysv ipc permission structure
3719  * @cmd: operation
3720  *
3721  * Check permission when a semaphore operation specified by @cmd is to be
3722  * performed on the semaphore.
3723  *
3724  * Return: Returns 0 if permission is granted.
3725  */
3726 int security_sem_semctl(struct kern_ipc_perm *sma, int cmd)
3727 {
3728 	return call_int_hook(sem_semctl, 0, sma, cmd);
3729 }
3730 
3731 /**
3732  * security_sem_semop() - Check if a sysv semaphore operation is allowed
3733  * @sma: sysv ipc permission structure
3734  * @sops: operations to perform
3735  * @nsops: number of operations
3736  * @alter: flag indicating changes will be made
3737  *
3738  * Check permissions before performing operations on members of the semaphore
3739  * set. If the @alter flag is nonzero, the semaphore set may be modified.
3740  *
3741  * Return: Returns 0 if permission is granted.
3742  */
3743 int security_sem_semop(struct kern_ipc_perm *sma, struct sembuf *sops,
3744 		       unsigned nsops, int alter)
3745 {
3746 	return call_int_hook(sem_semop, 0, sma, sops, nsops, alter);
3747 }
3748 
3749 /**
3750  * security_d_instantiate() - Populate an inode's LSM state based on a dentry
3751  * @dentry: dentry
3752  * @inode: inode
3753  *
3754  * Fill in @inode security information for a @dentry if allowed.
3755  */
3756 void security_d_instantiate(struct dentry *dentry, struct inode *inode)
3757 {
3758 	if (unlikely(inode && IS_PRIVATE(inode)))
3759 		return;
3760 	call_void_hook(d_instantiate, dentry, inode);
3761 }
3762 EXPORT_SYMBOL(security_d_instantiate);
3763 
3764 /**
3765  * security_getprocattr() - Read an attribute for a task
3766  * @p: the task
3767  * @lsm: LSM name
3768  * @name: attribute name
3769  * @value: attribute value
3770  *
3771  * Read attribute @name for task @p and store it into @value if allowed.
3772  *
3773  * Return: Returns the length of @value on success, a negative value otherwise.
3774  */
3775 int security_getprocattr(struct task_struct *p, const char *lsm,
3776 			 const char *name, char **value)
3777 {
3778 	struct security_hook_list *hp;
3779 
3780 	hlist_for_each_entry(hp, &security_hook_heads.getprocattr, list) {
3781 		if (lsm != NULL && strcmp(lsm, hp->lsm))
3782 			continue;
3783 		return hp->hook.getprocattr(p, name, value);
3784 	}
3785 	return LSM_RET_DEFAULT(getprocattr);
3786 }
3787 
3788 /**
3789  * security_setprocattr() - Set an attribute for a task
3790  * @lsm: LSM name
3791  * @name: attribute name
3792  * @value: attribute value
3793  * @size: attribute value size
3794  *
3795  * Write (set) the current task's attribute @name to @value, size @size if
3796  * allowed.
3797  *
3798  * Return: Returns bytes written on success, a negative value otherwise.
3799  */
3800 int security_setprocattr(const char *lsm, const char *name, void *value,
3801 			 size_t size)
3802 {
3803 	struct security_hook_list *hp;
3804 
3805 	hlist_for_each_entry(hp, &security_hook_heads.setprocattr, list) {
3806 		if (lsm != NULL && strcmp(lsm, hp->lsm))
3807 			continue;
3808 		return hp->hook.setprocattr(name, value, size);
3809 	}
3810 	return LSM_RET_DEFAULT(setprocattr);
3811 }
3812 
3813 /**
3814  * security_netlink_send() - Save info and check if netlink sending is allowed
3815  * @sk: sending socket
3816  * @skb: netlink message
3817  *
3818  * Save security information for a netlink message so that permission checking
3819  * can be performed when the message is processed.  The security information
3820  * can be saved using the eff_cap field of the netlink_skb_parms structure.
3821  * Also may be used to provide fine grained control over message transmission.
3822  *
3823  * Return: Returns 0 if the information was successfully saved and message is
3824  *         allowed to be transmitted.
3825  */
3826 int security_netlink_send(struct sock *sk, struct sk_buff *skb)
3827 {
3828 	return call_int_hook(netlink_send, 0, sk, skb);
3829 }
3830 
3831 /**
3832  * security_ismaclabel() - Check is the named attribute is a MAC label
3833  * @name: full extended attribute name
3834  *
3835  * Check if the extended attribute specified by @name represents a MAC label.
3836  *
3837  * Return: Returns 1 if name is a MAC attribute otherwise returns 0.
3838  */
3839 int security_ismaclabel(const char *name)
3840 {
3841 	return call_int_hook(ismaclabel, 0, name);
3842 }
3843 EXPORT_SYMBOL(security_ismaclabel);
3844 
3845 /**
3846  * security_secid_to_secctx() - Convert a secid to a secctx
3847  * @secid: secid
3848  * @secdata: secctx
3849  * @seclen: secctx length
3850  *
3851  * Convert secid to security context.  If @secdata is NULL the length of the
3852  * result will be returned in @seclen, but no @secdata will be returned.  This
3853  * does mean that the length could change between calls to check the length and
3854  * the next call which actually allocates and returns the @secdata.
3855  *
3856  * Return: Return 0 on success, error on failure.
3857  */
3858 int security_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
3859 {
3860 	struct security_hook_list *hp;
3861 	int rc;
3862 
3863 	/*
3864 	 * Currently, only one LSM can implement secid_to_secctx (i.e this
3865 	 * LSM hook is not "stackable").
3866 	 */
3867 	hlist_for_each_entry(hp, &security_hook_heads.secid_to_secctx, list) {
3868 		rc = hp->hook.secid_to_secctx(secid, secdata, seclen);
3869 		if (rc != LSM_RET_DEFAULT(secid_to_secctx))
3870 			return rc;
3871 	}
3872 
3873 	return LSM_RET_DEFAULT(secid_to_secctx);
3874 }
3875 EXPORT_SYMBOL(security_secid_to_secctx);
3876 
3877 /**
3878  * security_secctx_to_secid() - Convert a secctx to a secid
3879  * @secdata: secctx
3880  * @seclen: length of secctx
3881  * @secid: secid
3882  *
3883  * Convert security context to secid.
3884  *
3885  * Return: Returns 0 on success, error on failure.
3886  */
3887 int security_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
3888 {
3889 	*secid = 0;
3890 	return call_int_hook(secctx_to_secid, 0, secdata, seclen, secid);
3891 }
3892 EXPORT_SYMBOL(security_secctx_to_secid);
3893 
3894 /**
3895  * security_release_secctx() - Free a secctx buffer
3896  * @secdata: secctx
3897  * @seclen: length of secctx
3898  *
3899  * Release the security context.
3900  */
3901 void security_release_secctx(char *secdata, u32 seclen)
3902 {
3903 	call_void_hook(release_secctx, secdata, seclen);
3904 }
3905 EXPORT_SYMBOL(security_release_secctx);
3906 
3907 /**
3908  * security_inode_invalidate_secctx() - Invalidate an inode's security label
3909  * @inode: inode
3910  *
3911  * Notify the security module that it must revalidate the security context of
3912  * an inode.
3913  */
3914 void security_inode_invalidate_secctx(struct inode *inode)
3915 {
3916 	call_void_hook(inode_invalidate_secctx, inode);
3917 }
3918 EXPORT_SYMBOL(security_inode_invalidate_secctx);
3919 
3920 /**
3921  * security_inode_notifysecctx() - Nofify the LSM of an inode's security label
3922  * @inode: inode
3923  * @ctx: secctx
3924  * @ctxlen: length of secctx
3925  *
3926  * Notify the security module of what the security context of an inode should
3927  * be.  Initializes the incore security context managed by the security module
3928  * for this inode.  Example usage: NFS client invokes this hook to initialize
3929  * the security context in its incore inode to the value provided by the server
3930  * for the file when the server returned the file's attributes to the client.
3931  * Must be called with inode->i_mutex locked.
3932  *
3933  * Return: Returns 0 on success, error on failure.
3934  */
3935 int security_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen)
3936 {
3937 	return call_int_hook(inode_notifysecctx, 0, inode, ctx, ctxlen);
3938 }
3939 EXPORT_SYMBOL(security_inode_notifysecctx);
3940 
3941 /**
3942  * security_inode_setsecctx() - Change the security label of an inode
3943  * @dentry: inode
3944  * @ctx: secctx
3945  * @ctxlen: length of secctx
3946  *
3947  * Change the security context of an inode.  Updates the incore security
3948  * context managed by the security module and invokes the fs code as needed
3949  * (via __vfs_setxattr_noperm) to update any backing xattrs that represent the
3950  * context.  Example usage: NFS server invokes this hook to change the security
3951  * context in its incore inode and on the backing filesystem to a value
3952  * provided by the client on a SETATTR operation.  Must be called with
3953  * inode->i_mutex locked.
3954  *
3955  * Return: Returns 0 on success, error on failure.
3956  */
3957 int security_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen)
3958 {
3959 	return call_int_hook(inode_setsecctx, 0, dentry, ctx, ctxlen);
3960 }
3961 EXPORT_SYMBOL(security_inode_setsecctx);
3962 
3963 /**
3964  * security_inode_getsecctx() - Get the security label of an inode
3965  * @inode: inode
3966  * @ctx: secctx
3967  * @ctxlen: length of secctx
3968  *
3969  * On success, returns 0 and fills out @ctx and @ctxlen with the security
3970  * context for the given @inode.
3971  *
3972  * Return: Returns 0 on success, error on failure.
3973  */
3974 int security_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen)
3975 {
3976 	return call_int_hook(inode_getsecctx, -EOPNOTSUPP, inode, ctx, ctxlen);
3977 }
3978 EXPORT_SYMBOL(security_inode_getsecctx);
3979 
3980 #ifdef CONFIG_WATCH_QUEUE
3981 /**
3982  * security_post_notification() - Check if a watch notification can be posted
3983  * @w_cred: credentials of the task that set the watch
3984  * @cred: credentials of the task which triggered the watch
3985  * @n: the notification
3986  *
3987  * Check to see if a watch notification can be posted to a particular queue.
3988  *
3989  * Return: Returns 0 if permission is granted.
3990  */
3991 int security_post_notification(const struct cred *w_cred,
3992 			       const struct cred *cred,
3993 			       struct watch_notification *n)
3994 {
3995 	return call_int_hook(post_notification, 0, w_cred, cred, n);
3996 }
3997 #endif /* CONFIG_WATCH_QUEUE */
3998 
3999 #ifdef CONFIG_KEY_NOTIFICATIONS
4000 /**
4001  * security_watch_key() - Check if a task is allowed to watch for key events
4002  * @key: the key to watch
4003  *
4004  * Check to see if a process is allowed to watch for event notifications from
4005  * a key or keyring.
4006  *
4007  * Return: Returns 0 if permission is granted.
4008  */
4009 int security_watch_key(struct key *key)
4010 {
4011 	return call_int_hook(watch_key, 0, key);
4012 }
4013 #endif /* CONFIG_KEY_NOTIFICATIONS */
4014 
4015 #ifdef CONFIG_SECURITY_NETWORK
4016 /**
4017  * security_unix_stream_connect() - Check if a AF_UNIX stream is allowed
4018  * @sock: originating sock
4019  * @other: peer sock
4020  * @newsk: new sock
4021  *
4022  * Check permissions before establishing a Unix domain stream connection
4023  * between @sock and @other.
4024  *
4025  * The @unix_stream_connect and @unix_may_send hooks were necessary because
4026  * Linux provides an alternative to the conventional file name space for Unix
4027  * domain sockets.  Whereas binding and connecting to sockets in the file name
4028  * space is mediated by the typical file permissions (and caught by the mknod
4029  * and permission hooks in inode_security_ops), binding and connecting to
4030  * sockets in the abstract name space is completely unmediated.  Sufficient
4031  * control of Unix domain sockets in the abstract name space isn't possible
4032  * using only the socket layer hooks, since we need to know the actual target
4033  * socket, which is not looked up until we are inside the af_unix code.
4034  *
4035  * Return: Returns 0 if permission is granted.
4036  */
4037 int security_unix_stream_connect(struct sock *sock, struct sock *other,
4038 				 struct sock *newsk)
4039 {
4040 	return call_int_hook(unix_stream_connect, 0, sock, other, newsk);
4041 }
4042 EXPORT_SYMBOL(security_unix_stream_connect);
4043 
4044 /**
4045  * security_unix_may_send() - Check if AF_UNIX socket can send datagrams
4046  * @sock: originating sock
4047  * @other: peer sock
4048  *
4049  * Check permissions before connecting or sending datagrams from @sock to
4050  * @other.
4051  *
4052  * The @unix_stream_connect and @unix_may_send hooks were necessary because
4053  * Linux provides an alternative to the conventional file name space for Unix
4054  * domain sockets.  Whereas binding and connecting to sockets in the file name
4055  * space is mediated by the typical file permissions (and caught by the mknod
4056  * and permission hooks in inode_security_ops), binding and connecting to
4057  * sockets in the abstract name space is completely unmediated.  Sufficient
4058  * control of Unix domain sockets in the abstract name space isn't possible
4059  * using only the socket layer hooks, since we need to know the actual target
4060  * socket, which is not looked up until we are inside the af_unix code.
4061  *
4062  * Return: Returns 0 if permission is granted.
4063  */
4064 int security_unix_may_send(struct socket *sock,  struct socket *other)
4065 {
4066 	return call_int_hook(unix_may_send, 0, sock, other);
4067 }
4068 EXPORT_SYMBOL(security_unix_may_send);
4069 
4070 /**
4071  * security_socket_create() - Check if creating a new socket is allowed
4072  * @family: protocol family
4073  * @type: communications type
4074  * @protocol: requested protocol
4075  * @kern: set to 1 if a kernel socket is requested
4076  *
4077  * Check permissions prior to creating a new socket.
4078  *
4079  * Return: Returns 0 if permission is granted.
4080  */
4081 int security_socket_create(int family, int type, int protocol, int kern)
4082 {
4083 	return call_int_hook(socket_create, 0, family, type, protocol, kern);
4084 }
4085 
4086 /**
4087  * security_socket_post_create() - Initialize a newly created socket
4088  * @sock: socket
4089  * @family: protocol family
4090  * @type: communications type
4091  * @protocol: requested protocol
4092  * @kern: set to 1 if a kernel socket is requested
4093  *
4094  * This hook allows a module to update or allocate a per-socket security
4095  * structure. Note that the security field was not added directly to the socket
4096  * structure, but rather, the socket security information is stored in the
4097  * associated inode.  Typically, the inode alloc_security hook will allocate
4098  * and attach security information to SOCK_INODE(sock)->i_security.  This hook
4099  * may be used to update the SOCK_INODE(sock)->i_security field with additional
4100  * information that wasn't available when the inode was allocated.
4101  *
4102  * Return: Returns 0 if permission is granted.
4103  */
4104 int security_socket_post_create(struct socket *sock, int family,
4105 				int type, int protocol, int kern)
4106 {
4107 	return call_int_hook(socket_post_create, 0, sock, family, type,
4108 			     protocol, kern);
4109 }
4110 
4111 /**
4112  * security_socket_socketpair() - Check if creating a socketpair is allowed
4113  * @socka: first socket
4114  * @sockb: second socket
4115  *
4116  * Check permissions before creating a fresh pair of sockets.
4117  *
4118  * Return: Returns 0 if permission is granted and the connection was
4119  *         established.
4120  */
4121 int security_socket_socketpair(struct socket *socka, struct socket *sockb)
4122 {
4123 	return call_int_hook(socket_socketpair, 0, socka, sockb);
4124 }
4125 EXPORT_SYMBOL(security_socket_socketpair);
4126 
4127 /**
4128  * security_socket_bind() - Check if a socket bind operation is allowed
4129  * @sock: socket
4130  * @address: requested bind address
4131  * @addrlen: length of address
4132  *
4133  * Check permission before socket protocol layer bind operation is performed
4134  * and the socket @sock is bound to the address specified in the @address
4135  * parameter.
4136  *
4137  * Return: Returns 0 if permission is granted.
4138  */
4139 int security_socket_bind(struct socket *sock,
4140 			 struct sockaddr *address, int addrlen)
4141 {
4142 	return call_int_hook(socket_bind, 0, sock, address, addrlen);
4143 }
4144 
4145 /**
4146  * security_socket_connect() - Check if a socket connect operation is allowed
4147  * @sock: socket
4148  * @address: address of remote connection point
4149  * @addrlen: length of address
4150  *
4151  * Check permission before socket protocol layer connect operation attempts to
4152  * connect socket @sock to a remote address, @address.
4153  *
4154  * Return: Returns 0 if permission is granted.
4155  */
4156 int security_socket_connect(struct socket *sock,
4157 			    struct sockaddr *address, int addrlen)
4158 {
4159 	return call_int_hook(socket_connect, 0, sock, address, addrlen);
4160 }
4161 
4162 /**
4163  * security_socket_listen() - Check if a socket is allowed to listen
4164  * @sock: socket
4165  * @backlog: connection queue size
4166  *
4167  * Check permission before socket protocol layer listen operation.
4168  *
4169  * Return: Returns 0 if permission is granted.
4170  */
4171 int security_socket_listen(struct socket *sock, int backlog)
4172 {
4173 	return call_int_hook(socket_listen, 0, sock, backlog);
4174 }
4175 
4176 /**
4177  * security_socket_accept() - Check if a socket is allowed to accept connections
4178  * @sock: listening socket
4179  * @newsock: newly creation connection socket
4180  *
4181  * Check permission before accepting a new connection.  Note that the new
4182  * socket, @newsock, has been created and some information copied to it, but
4183  * the accept operation has not actually been performed.
4184  *
4185  * Return: Returns 0 if permission is granted.
4186  */
4187 int security_socket_accept(struct socket *sock, struct socket *newsock)
4188 {
4189 	return call_int_hook(socket_accept, 0, sock, newsock);
4190 }
4191 
4192 /**
4193  * security_socket_sendmsg() - Check is sending a message is allowed
4194  * @sock: sending socket
4195  * @msg: message to send
4196  * @size: size of message
4197  *
4198  * Check permission before transmitting a message to another socket.
4199  *
4200  * Return: Returns 0 if permission is granted.
4201  */
4202 int security_socket_sendmsg(struct socket *sock, struct msghdr *msg, int size)
4203 {
4204 	return call_int_hook(socket_sendmsg, 0, sock, msg, size);
4205 }
4206 
4207 /**
4208  * security_socket_recvmsg() - Check if receiving a message is allowed
4209  * @sock: receiving socket
4210  * @msg: message to receive
4211  * @size: size of message
4212  * @flags: operational flags
4213  *
4214  * Check permission before receiving a message from a socket.
4215  *
4216  * Return: Returns 0 if permission is granted.
4217  */
4218 int security_socket_recvmsg(struct socket *sock, struct msghdr *msg,
4219 			    int size, int flags)
4220 {
4221 	return call_int_hook(socket_recvmsg, 0, sock, msg, size, flags);
4222 }
4223 
4224 /**
4225  * security_socket_getsockname() - Check if reading the socket addr is allowed
4226  * @sock: socket
4227  *
4228  * Check permission before reading the local address (name) of the socket
4229  * object.
4230  *
4231  * Return: Returns 0 if permission is granted.
4232  */
4233 int security_socket_getsockname(struct socket *sock)
4234 {
4235 	return call_int_hook(socket_getsockname, 0, sock);
4236 }
4237 
4238 /**
4239  * security_socket_getpeername() - Check if reading the peer's addr is allowed
4240  * @sock: socket
4241  *
4242  * Check permission before the remote address (name) of a socket object.
4243  *
4244  * Return: Returns 0 if permission is granted.
4245  */
4246 int security_socket_getpeername(struct socket *sock)
4247 {
4248 	return call_int_hook(socket_getpeername, 0, sock);
4249 }
4250 
4251 /**
4252  * security_socket_getsockopt() - Check if reading a socket option is allowed
4253  * @sock: socket
4254  * @level: option's protocol level
4255  * @optname: option name
4256  *
4257  * Check permissions before retrieving the options associated with socket
4258  * @sock.
4259  *
4260  * Return: Returns 0 if permission is granted.
4261  */
4262 int security_socket_getsockopt(struct socket *sock, int level, int optname)
4263 {
4264 	return call_int_hook(socket_getsockopt, 0, sock, level, optname);
4265 }
4266 
4267 /**
4268  * security_socket_setsockopt() - Check if setting a socket option is allowed
4269  * @sock: socket
4270  * @level: option's protocol level
4271  * @optname: option name
4272  *
4273  * Check permissions before setting the options associated with socket @sock.
4274  *
4275  * Return: Returns 0 if permission is granted.
4276  */
4277 int security_socket_setsockopt(struct socket *sock, int level, int optname)
4278 {
4279 	return call_int_hook(socket_setsockopt, 0, sock, level, optname);
4280 }
4281 
4282 /**
4283  * security_socket_shutdown() - Checks if shutting down the socket is allowed
4284  * @sock: socket
4285  * @how: flag indicating how sends and receives are handled
4286  *
4287  * Checks permission before all or part of a connection on the socket @sock is
4288  * shut down.
4289  *
4290  * Return: Returns 0 if permission is granted.
4291  */
4292 int security_socket_shutdown(struct socket *sock, int how)
4293 {
4294 	return call_int_hook(socket_shutdown, 0, sock, how);
4295 }
4296 
4297 /**
4298  * security_sock_rcv_skb() - Check if an incoming network packet is allowed
4299  * @sk: destination sock
4300  * @skb: incoming packet
4301  *
4302  * Check permissions on incoming network packets.  This hook is distinct from
4303  * Netfilter's IP input hooks since it is the first time that the incoming
4304  * sk_buff @skb has been associated with a particular socket, @sk.  Must not
4305  * sleep inside this hook because some callers hold spinlocks.
4306  *
4307  * Return: Returns 0 if permission is granted.
4308  */
4309 int security_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
4310 {
4311 	return call_int_hook(socket_sock_rcv_skb, 0, sk, skb);
4312 }
4313 EXPORT_SYMBOL(security_sock_rcv_skb);
4314 
4315 /**
4316  * security_socket_getpeersec_stream() - Get the remote peer label
4317  * @sock: socket
4318  * @optval: destination buffer
4319  * @optlen: size of peer label copied into the buffer
4320  * @len: maximum size of the destination buffer
4321  *
4322  * This hook allows the security module to provide peer socket security state
4323  * for unix or connected tcp sockets to userspace via getsockopt SO_GETPEERSEC.
4324  * For tcp sockets this can be meaningful if the socket is associated with an
4325  * ipsec SA.
4326  *
4327  * Return: Returns 0 if all is well, otherwise, typical getsockopt return
4328  *         values.
4329  */
4330 int security_socket_getpeersec_stream(struct socket *sock, sockptr_t optval,
4331 				      sockptr_t optlen, unsigned int len)
4332 {
4333 	return call_int_hook(socket_getpeersec_stream, -ENOPROTOOPT, sock,
4334 			     optval, optlen, len);
4335 }
4336 
4337 /**
4338  * security_socket_getpeersec_dgram() - Get the remote peer label
4339  * @sock: socket
4340  * @skb: datagram packet
4341  * @secid: remote peer label secid
4342  *
4343  * This hook allows the security module to provide peer socket security state
4344  * for udp sockets on a per-packet basis to userspace via getsockopt
4345  * SO_GETPEERSEC. The application must first have indicated the IP_PASSSEC
4346  * option via getsockopt. It can then retrieve the security state returned by
4347  * this hook for a packet via the SCM_SECURITY ancillary message type.
4348  *
4349  * Return: Returns 0 on success, error on failure.
4350  */
4351 int security_socket_getpeersec_dgram(struct socket *sock,
4352 				     struct sk_buff *skb, u32 *secid)
4353 {
4354 	return call_int_hook(socket_getpeersec_dgram, -ENOPROTOOPT, sock,
4355 			     skb, secid);
4356 }
4357 EXPORT_SYMBOL(security_socket_getpeersec_dgram);
4358 
4359 /**
4360  * security_sk_alloc() - Allocate and initialize a sock's LSM blob
4361  * @sk: sock
4362  * @family: protocol family
4363  * @priority: gfp flags
4364  *
4365  * Allocate and attach a security structure to the sk->sk_security field, which
4366  * is used to copy security attributes between local stream sockets.
4367  *
4368  * Return: Returns 0 on success, error on failure.
4369  */
4370 int security_sk_alloc(struct sock *sk, int family, gfp_t priority)
4371 {
4372 	return call_int_hook(sk_alloc_security, 0, sk, family, priority);
4373 }
4374 
4375 /**
4376  * security_sk_free() - Free the sock's LSM blob
4377  * @sk: sock
4378  *
4379  * Deallocate security structure.
4380  */
4381 void security_sk_free(struct sock *sk)
4382 {
4383 	call_void_hook(sk_free_security, sk);
4384 }
4385 
4386 /**
4387  * security_sk_clone() - Clone a sock's LSM state
4388  * @sk: original sock
4389  * @newsk: target sock
4390  *
4391  * Clone/copy security structure.
4392  */
4393 void security_sk_clone(const struct sock *sk, struct sock *newsk)
4394 {
4395 	call_void_hook(sk_clone_security, sk, newsk);
4396 }
4397 EXPORT_SYMBOL(security_sk_clone);
4398 
4399 void security_sk_classify_flow(struct sock *sk, struct flowi_common *flic)
4400 {
4401 	call_void_hook(sk_getsecid, sk, &flic->flowic_secid);
4402 }
4403 EXPORT_SYMBOL(security_sk_classify_flow);
4404 
4405 /**
4406  * security_req_classify_flow() - Set a flow's secid based on request_sock
4407  * @req: request_sock
4408  * @flic: target flow
4409  *
4410  * Sets @flic's secid to @req's secid.
4411  */
4412 void security_req_classify_flow(const struct request_sock *req,
4413 				struct flowi_common *flic)
4414 {
4415 	call_void_hook(req_classify_flow, req, flic);
4416 }
4417 EXPORT_SYMBOL(security_req_classify_flow);
4418 
4419 /**
4420  * security_sock_graft() - Reconcile LSM state when grafting a sock on a socket
4421  * @sk: sock being grafted
4422  * @parent: target parent socket
4423  *
4424  * Sets @parent's inode secid to @sk's secid and update @sk with any necessary
4425  * LSM state from @parent.
4426  */
4427 void security_sock_graft(struct sock *sk, struct socket *parent)
4428 {
4429 	call_void_hook(sock_graft, sk, parent);
4430 }
4431 EXPORT_SYMBOL(security_sock_graft);
4432 
4433 /**
4434  * security_inet_conn_request() - Set request_sock state using incoming connect
4435  * @sk: parent listening sock
4436  * @skb: incoming connection
4437  * @req: new request_sock
4438  *
4439  * Initialize the @req LSM state based on @sk and the incoming connect in @skb.
4440  *
4441  * Return: Returns 0 if permission is granted.
4442  */
4443 int security_inet_conn_request(const struct sock *sk,
4444 			       struct sk_buff *skb, struct request_sock *req)
4445 {
4446 	return call_int_hook(inet_conn_request, 0, sk, skb, req);
4447 }
4448 EXPORT_SYMBOL(security_inet_conn_request);
4449 
4450 /**
4451  * security_inet_csk_clone() - Set new sock LSM state based on request_sock
4452  * @newsk: new sock
4453  * @req: connection request_sock
4454  *
4455  * Set that LSM state of @sock using the LSM state from @req.
4456  */
4457 void security_inet_csk_clone(struct sock *newsk,
4458 			     const struct request_sock *req)
4459 {
4460 	call_void_hook(inet_csk_clone, newsk, req);
4461 }
4462 
4463 /**
4464  * security_inet_conn_established() - Update sock's LSM state with connection
4465  * @sk: sock
4466  * @skb: connection packet
4467  *
4468  * Update @sock's LSM state to represent a new connection from @skb.
4469  */
4470 void security_inet_conn_established(struct sock *sk,
4471 				    struct sk_buff *skb)
4472 {
4473 	call_void_hook(inet_conn_established, sk, skb);
4474 }
4475 EXPORT_SYMBOL(security_inet_conn_established);
4476 
4477 /**
4478  * security_secmark_relabel_packet() - Check if setting a secmark is allowed
4479  * @secid: new secmark value
4480  *
4481  * Check if the process should be allowed to relabel packets to @secid.
4482  *
4483  * Return: Returns 0 if permission is granted.
4484  */
4485 int security_secmark_relabel_packet(u32 secid)
4486 {
4487 	return call_int_hook(secmark_relabel_packet, 0, secid);
4488 }
4489 EXPORT_SYMBOL(security_secmark_relabel_packet);
4490 
4491 /**
4492  * security_secmark_refcount_inc() - Increment the secmark labeling rule count
4493  *
4494  * Tells the LSM to increment the number of secmark labeling rules loaded.
4495  */
4496 void security_secmark_refcount_inc(void)
4497 {
4498 	call_void_hook(secmark_refcount_inc);
4499 }
4500 EXPORT_SYMBOL(security_secmark_refcount_inc);
4501 
4502 /**
4503  * security_secmark_refcount_dec() - Decrement the secmark labeling rule count
4504  *
4505  * Tells the LSM to decrement the number of secmark labeling rules loaded.
4506  */
4507 void security_secmark_refcount_dec(void)
4508 {
4509 	call_void_hook(secmark_refcount_dec);
4510 }
4511 EXPORT_SYMBOL(security_secmark_refcount_dec);
4512 
4513 /**
4514  * security_tun_dev_alloc_security() - Allocate a LSM blob for a TUN device
4515  * @security: pointer to the LSM blob
4516  *
4517  * This hook allows a module to allocate a security structure for a TUN	device,
4518  * returning the pointer in @security.
4519  *
4520  * Return: Returns a zero on success, negative values on failure.
4521  */
4522 int security_tun_dev_alloc_security(void **security)
4523 {
4524 	return call_int_hook(tun_dev_alloc_security, 0, security);
4525 }
4526 EXPORT_SYMBOL(security_tun_dev_alloc_security);
4527 
4528 /**
4529  * security_tun_dev_free_security() - Free a TUN device LSM blob
4530  * @security: LSM blob
4531  *
4532  * This hook allows a module to free the security structure for a TUN device.
4533  */
4534 void security_tun_dev_free_security(void *security)
4535 {
4536 	call_void_hook(tun_dev_free_security, security);
4537 }
4538 EXPORT_SYMBOL(security_tun_dev_free_security);
4539 
4540 /**
4541  * security_tun_dev_create() - Check if creating a TUN device is allowed
4542  *
4543  * Check permissions prior to creating a new TUN device.
4544  *
4545  * Return: Returns 0 if permission is granted.
4546  */
4547 int security_tun_dev_create(void)
4548 {
4549 	return call_int_hook(tun_dev_create, 0);
4550 }
4551 EXPORT_SYMBOL(security_tun_dev_create);
4552 
4553 /**
4554  * security_tun_dev_attach_queue() - Check if attaching a TUN queue is allowed
4555  * @security: TUN device LSM blob
4556  *
4557  * Check permissions prior to attaching to a TUN device queue.
4558  *
4559  * Return: Returns 0 if permission is granted.
4560  */
4561 int security_tun_dev_attach_queue(void *security)
4562 {
4563 	return call_int_hook(tun_dev_attach_queue, 0, security);
4564 }
4565 EXPORT_SYMBOL(security_tun_dev_attach_queue);
4566 
4567 /**
4568  * security_tun_dev_attach() - Update TUN device LSM state on attach
4569  * @sk: associated sock
4570  * @security: TUN device LSM blob
4571  *
4572  * This hook can be used by the module to update any security state associated
4573  * with the TUN device's sock structure.
4574  *
4575  * Return: Returns 0 if permission is granted.
4576  */
4577 int security_tun_dev_attach(struct sock *sk, void *security)
4578 {
4579 	return call_int_hook(tun_dev_attach, 0, sk, security);
4580 }
4581 EXPORT_SYMBOL(security_tun_dev_attach);
4582 
4583 /**
4584  * security_tun_dev_open() - Update TUN device LSM state on open
4585  * @security: TUN device LSM blob
4586  *
4587  * This hook can be used by the module to update any security state associated
4588  * with the TUN device's security structure.
4589  *
4590  * Return: Returns 0 if permission is granted.
4591  */
4592 int security_tun_dev_open(void *security)
4593 {
4594 	return call_int_hook(tun_dev_open, 0, security);
4595 }
4596 EXPORT_SYMBOL(security_tun_dev_open);
4597 
4598 /**
4599  * security_sctp_assoc_request() - Update the LSM on a SCTP association req
4600  * @asoc: SCTP association
4601  * @skb: packet requesting the association
4602  *
4603  * Passes the @asoc and @chunk->skb of the association INIT packet to the LSM.
4604  *
4605  * Return: Returns 0 on success, error on failure.
4606  */
4607 int security_sctp_assoc_request(struct sctp_association *asoc,
4608 				struct sk_buff *skb)
4609 {
4610 	return call_int_hook(sctp_assoc_request, 0, asoc, skb);
4611 }
4612 EXPORT_SYMBOL(security_sctp_assoc_request);
4613 
4614 /**
4615  * security_sctp_bind_connect() - Validate a list of addrs for a SCTP option
4616  * @sk: socket
4617  * @optname: SCTP option to validate
4618  * @address: list of IP addresses to validate
4619  * @addrlen: length of the address list
4620  *
4621  * Validiate permissions required for each address associated with sock	@sk.
4622  * Depending on @optname, the addresses will be treated as either a connect or
4623  * bind service. The @addrlen is calculated on each IPv4 and IPv6 address using
4624  * sizeof(struct sockaddr_in) or sizeof(struct sockaddr_in6).
4625  *
4626  * Return: Returns 0 on success, error on failure.
4627  */
4628 int security_sctp_bind_connect(struct sock *sk, int optname,
4629 			       struct sockaddr *address, int addrlen)
4630 {
4631 	return call_int_hook(sctp_bind_connect, 0, sk, optname,
4632 			     address, addrlen);
4633 }
4634 EXPORT_SYMBOL(security_sctp_bind_connect);
4635 
4636 /**
4637  * security_sctp_sk_clone() - Clone a SCTP sock's LSM state
4638  * @asoc: SCTP association
4639  * @sk: original sock
4640  * @newsk: target sock
4641  *
4642  * Called whenever a new socket is created by accept(2) (i.e. a TCP style
4643  * socket) or when a socket is 'peeled off' e.g userspace calls
4644  * sctp_peeloff(3).
4645  */
4646 void security_sctp_sk_clone(struct sctp_association *asoc, struct sock *sk,
4647 			    struct sock *newsk)
4648 {
4649 	call_void_hook(sctp_sk_clone, asoc, sk, newsk);
4650 }
4651 EXPORT_SYMBOL(security_sctp_sk_clone);
4652 
4653 /**
4654  * security_sctp_assoc_established() - Update LSM state when assoc established
4655  * @asoc: SCTP association
4656  * @skb: packet establishing the association
4657  *
4658  * Passes the @asoc and @chunk->skb of the association COOKIE_ACK packet to the
4659  * security module.
4660  *
4661  * Return: Returns 0 if permission is granted.
4662  */
4663 int security_sctp_assoc_established(struct sctp_association *asoc,
4664 				    struct sk_buff *skb)
4665 {
4666 	return call_int_hook(sctp_assoc_established, 0, asoc, skb);
4667 }
4668 EXPORT_SYMBOL(security_sctp_assoc_established);
4669 
4670 /**
4671  * security_mptcp_add_subflow() - Inherit the LSM label from the MPTCP socket
4672  * @sk: the owning MPTCP socket
4673  * @ssk: the new subflow
4674  *
4675  * Update the labeling for the given MPTCP subflow, to match the one of the
4676  * owning MPTCP socket. This hook has to be called after the socket creation and
4677  * initialization via the security_socket_create() and
4678  * security_socket_post_create() LSM hooks.
4679  *
4680  * Return: Returns 0 on success or a negative error code on failure.
4681  */
4682 int security_mptcp_add_subflow(struct sock *sk, struct sock *ssk)
4683 {
4684 	return call_int_hook(mptcp_add_subflow, 0, sk, ssk);
4685 }
4686 
4687 #endif	/* CONFIG_SECURITY_NETWORK */
4688 
4689 #ifdef CONFIG_SECURITY_INFINIBAND
4690 /**
4691  * security_ib_pkey_access() - Check if access to an IB pkey is allowed
4692  * @sec: LSM blob
4693  * @subnet_prefix: subnet prefix of the port
4694  * @pkey: IB pkey
4695  *
4696  * Check permission to access a pkey when modifying a QP.
4697  *
4698  * Return: Returns 0 if permission is granted.
4699  */
4700 int security_ib_pkey_access(void *sec, u64 subnet_prefix, u16 pkey)
4701 {
4702 	return call_int_hook(ib_pkey_access, 0, sec, subnet_prefix, pkey);
4703 }
4704 EXPORT_SYMBOL(security_ib_pkey_access);
4705 
4706 /**
4707  * security_ib_endport_manage_subnet() - Check if SMPs traffic is allowed
4708  * @sec: LSM blob
4709  * @dev_name: IB device name
4710  * @port_num: port number
4711  *
4712  * Check permissions to send and receive SMPs on a end port.
4713  *
4714  * Return: Returns 0 if permission is granted.
4715  */
4716 int security_ib_endport_manage_subnet(void *sec,
4717 				      const char *dev_name, u8 port_num)
4718 {
4719 	return call_int_hook(ib_endport_manage_subnet, 0, sec,
4720 			     dev_name, port_num);
4721 }
4722 EXPORT_SYMBOL(security_ib_endport_manage_subnet);
4723 
4724 /**
4725  * security_ib_alloc_security() - Allocate an Infiniband LSM blob
4726  * @sec: LSM blob
4727  *
4728  * Allocate a security structure for Infiniband objects.
4729  *
4730  * Return: Returns 0 on success, non-zero on failure.
4731  */
4732 int security_ib_alloc_security(void **sec)
4733 {
4734 	return call_int_hook(ib_alloc_security, 0, sec);
4735 }
4736 EXPORT_SYMBOL(security_ib_alloc_security);
4737 
4738 /**
4739  * security_ib_free_security() - Free an Infiniband LSM blob
4740  * @sec: LSM blob
4741  *
4742  * Deallocate an Infiniband security structure.
4743  */
4744 void security_ib_free_security(void *sec)
4745 {
4746 	call_void_hook(ib_free_security, sec);
4747 }
4748 EXPORT_SYMBOL(security_ib_free_security);
4749 #endif	/* CONFIG_SECURITY_INFINIBAND */
4750 
4751 #ifdef CONFIG_SECURITY_NETWORK_XFRM
4752 /**
4753  * security_xfrm_policy_alloc() - Allocate a xfrm policy LSM blob
4754  * @ctxp: xfrm security context being added to the SPD
4755  * @sec_ctx: security label provided by userspace
4756  * @gfp: gfp flags
4757  *
4758  * Allocate a security structure to the xp->security field; the security field
4759  * is initialized to NULL when the xfrm_policy is allocated.
4760  *
4761  * Return:  Return 0 if operation was successful.
4762  */
4763 int security_xfrm_policy_alloc(struct xfrm_sec_ctx **ctxp,
4764 			       struct xfrm_user_sec_ctx *sec_ctx,
4765 			       gfp_t gfp)
4766 {
4767 	return call_int_hook(xfrm_policy_alloc_security, 0, ctxp, sec_ctx, gfp);
4768 }
4769 EXPORT_SYMBOL(security_xfrm_policy_alloc);
4770 
4771 /**
4772  * security_xfrm_policy_clone() - Clone xfrm policy LSM state
4773  * @old_ctx: xfrm security context
4774  * @new_ctxp: target xfrm security context
4775  *
4776  * Allocate a security structure in new_ctxp that contains the information from
4777  * the old_ctx structure.
4778  *
4779  * Return: Return 0 if operation was successful.
4780  */
4781 int security_xfrm_policy_clone(struct xfrm_sec_ctx *old_ctx,
4782 			       struct xfrm_sec_ctx **new_ctxp)
4783 {
4784 	return call_int_hook(xfrm_policy_clone_security, 0, old_ctx, new_ctxp);
4785 }
4786 
4787 /**
4788  * security_xfrm_policy_free() - Free a xfrm security context
4789  * @ctx: xfrm security context
4790  *
4791  * Free LSM resources associated with @ctx.
4792  */
4793 void security_xfrm_policy_free(struct xfrm_sec_ctx *ctx)
4794 {
4795 	call_void_hook(xfrm_policy_free_security, ctx);
4796 }
4797 EXPORT_SYMBOL(security_xfrm_policy_free);
4798 
4799 /**
4800  * security_xfrm_policy_delete() - Check if deleting a xfrm policy is allowed
4801  * @ctx: xfrm security context
4802  *
4803  * Authorize deletion of a SPD entry.
4804  *
4805  * Return: Returns 0 if permission is granted.
4806  */
4807 int security_xfrm_policy_delete(struct xfrm_sec_ctx *ctx)
4808 {
4809 	return call_int_hook(xfrm_policy_delete_security, 0, ctx);
4810 }
4811 
4812 /**
4813  * security_xfrm_state_alloc() - Allocate a xfrm state LSM blob
4814  * @x: xfrm state being added to the SAD
4815  * @sec_ctx: security label provided by userspace
4816  *
4817  * Allocate a security structure to the @x->security field; the security field
4818  * is initialized to NULL when the xfrm_state is allocated. Set the context to
4819  * correspond to @sec_ctx.
4820  *
4821  * Return: Return 0 if operation was successful.
4822  */
4823 int security_xfrm_state_alloc(struct xfrm_state *x,
4824 			      struct xfrm_user_sec_ctx *sec_ctx)
4825 {
4826 	return call_int_hook(xfrm_state_alloc, 0, x, sec_ctx);
4827 }
4828 EXPORT_SYMBOL(security_xfrm_state_alloc);
4829 
4830 /**
4831  * security_xfrm_state_alloc_acquire() - Allocate a xfrm state LSM blob
4832  * @x: xfrm state being added to the SAD
4833  * @polsec: associated policy's security context
4834  * @secid: secid from the flow
4835  *
4836  * Allocate a security structure to the x->security field; the security field
4837  * is initialized to NULL when the xfrm_state is allocated.  Set the context to
4838  * correspond to secid.
4839  *
4840  * Return: Returns 0 if operation was successful.
4841  */
4842 int security_xfrm_state_alloc_acquire(struct xfrm_state *x,
4843 				      struct xfrm_sec_ctx *polsec, u32 secid)
4844 {
4845 	return call_int_hook(xfrm_state_alloc_acquire, 0, x, polsec, secid);
4846 }
4847 
4848 /**
4849  * security_xfrm_state_delete() - Check if deleting a xfrm state is allowed
4850  * @x: xfrm state
4851  *
4852  * Authorize deletion of x->security.
4853  *
4854  * Return: Returns 0 if permission is granted.
4855  */
4856 int security_xfrm_state_delete(struct xfrm_state *x)
4857 {
4858 	return call_int_hook(xfrm_state_delete_security, 0, x);
4859 }
4860 EXPORT_SYMBOL(security_xfrm_state_delete);
4861 
4862 /**
4863  * security_xfrm_state_free() - Free a xfrm state
4864  * @x: xfrm state
4865  *
4866  * Deallocate x->security.
4867  */
4868 void security_xfrm_state_free(struct xfrm_state *x)
4869 {
4870 	call_void_hook(xfrm_state_free_security, x);
4871 }
4872 
4873 /**
4874  * security_xfrm_policy_lookup() - Check if using a xfrm policy is allowed
4875  * @ctx: target xfrm security context
4876  * @fl_secid: flow secid used to authorize access
4877  *
4878  * Check permission when a flow selects a xfrm_policy for processing XFRMs on a
4879  * packet.  The hook is called when selecting either a per-socket policy or a
4880  * generic xfrm policy.
4881  *
4882  * Return: Return 0 if permission is granted, -ESRCH otherwise, or -errno on
4883  *         other errors.
4884  */
4885 int security_xfrm_policy_lookup(struct xfrm_sec_ctx *ctx, u32 fl_secid)
4886 {
4887 	return call_int_hook(xfrm_policy_lookup, 0, ctx, fl_secid);
4888 }
4889 
4890 /**
4891  * security_xfrm_state_pol_flow_match() - Check for a xfrm match
4892  * @x: xfrm state to match
4893  * @xp: xfrm policy to check for a match
4894  * @flic: flow to check for a match.
4895  *
4896  * Check @xp and @flic for a match with @x.
4897  *
4898  * Return: Returns 1 if there is a match.
4899  */
4900 int security_xfrm_state_pol_flow_match(struct xfrm_state *x,
4901 				       struct xfrm_policy *xp,
4902 				       const struct flowi_common *flic)
4903 {
4904 	struct security_hook_list *hp;
4905 	int rc = LSM_RET_DEFAULT(xfrm_state_pol_flow_match);
4906 
4907 	/*
4908 	 * Since this function is expected to return 0 or 1, the judgment
4909 	 * becomes difficult if multiple LSMs supply this call. Fortunately,
4910 	 * we can use the first LSM's judgment because currently only SELinux
4911 	 * supplies this call.
4912 	 *
4913 	 * For speed optimization, we explicitly break the loop rather than
4914 	 * using the macro
4915 	 */
4916 	hlist_for_each_entry(hp, &security_hook_heads.xfrm_state_pol_flow_match,
4917 			     list) {
4918 		rc = hp->hook.xfrm_state_pol_flow_match(x, xp, flic);
4919 		break;
4920 	}
4921 	return rc;
4922 }
4923 
4924 /**
4925  * security_xfrm_decode_session() - Determine the xfrm secid for a packet
4926  * @skb: xfrm packet
4927  * @secid: secid
4928  *
4929  * Decode the packet in @skb and return the security label in @secid.
4930  *
4931  * Return: Return 0 if all xfrms used have the same secid.
4932  */
4933 int security_xfrm_decode_session(struct sk_buff *skb, u32 *secid)
4934 {
4935 	return call_int_hook(xfrm_decode_session, 0, skb, secid, 1);
4936 }
4937 
4938 void security_skb_classify_flow(struct sk_buff *skb, struct flowi_common *flic)
4939 {
4940 	int rc = call_int_hook(xfrm_decode_session, 0, skb, &flic->flowic_secid,
4941 			       0);
4942 
4943 	BUG_ON(rc);
4944 }
4945 EXPORT_SYMBOL(security_skb_classify_flow);
4946 #endif	/* CONFIG_SECURITY_NETWORK_XFRM */
4947 
4948 #ifdef CONFIG_KEYS
4949 /**
4950  * security_key_alloc() - Allocate and initialize a kernel key LSM blob
4951  * @key: key
4952  * @cred: credentials
4953  * @flags: allocation flags
4954  *
4955  * Permit allocation of a key and assign security data. Note that key does not
4956  * have a serial number assigned at this point.
4957  *
4958  * Return: Return 0 if permission is granted, -ve error otherwise.
4959  */
4960 int security_key_alloc(struct key *key, const struct cred *cred,
4961 		       unsigned long flags)
4962 {
4963 	return call_int_hook(key_alloc, 0, key, cred, flags);
4964 }
4965 
4966 /**
4967  * security_key_free() - Free a kernel key LSM blob
4968  * @key: key
4969  *
4970  * Notification of destruction; free security data.
4971  */
4972 void security_key_free(struct key *key)
4973 {
4974 	call_void_hook(key_free, key);
4975 }
4976 
4977 /**
4978  * security_key_permission() - Check if a kernel key operation is allowed
4979  * @key_ref: key reference
4980  * @cred: credentials of actor requesting access
4981  * @need_perm: requested permissions
4982  *
4983  * See whether a specific operational right is granted to a process on a key.
4984  *
4985  * Return: Return 0 if permission is granted, -ve error otherwise.
4986  */
4987 int security_key_permission(key_ref_t key_ref, const struct cred *cred,
4988 			    enum key_need_perm need_perm)
4989 {
4990 	return call_int_hook(key_permission, 0, key_ref, cred, need_perm);
4991 }
4992 
4993 /**
4994  * security_key_getsecurity() - Get the key's security label
4995  * @key: key
4996  * @buffer: security label buffer
4997  *
4998  * Get a textual representation of the security context attached to a key for
4999  * the purposes of honouring KEYCTL_GETSECURITY.  This function allocates the
5000  * storage for the NUL-terminated string and the caller should free it.
5001  *
5002  * Return: Returns the length of @buffer (including terminating NUL) or -ve if
5003  *         an error occurs.  May also return 0 (and a NULL buffer pointer) if
5004  *         there is no security label assigned to the key.
5005  */
5006 int security_key_getsecurity(struct key *key, char **buffer)
5007 {
5008 	*buffer = NULL;
5009 	return call_int_hook(key_getsecurity, 0, key, buffer);
5010 }
5011 #endif	/* CONFIG_KEYS */
5012 
5013 #ifdef CONFIG_AUDIT
5014 /**
5015  * security_audit_rule_init() - Allocate and init an LSM audit rule struct
5016  * @field: audit action
5017  * @op: rule operator
5018  * @rulestr: rule context
5019  * @lsmrule: receive buffer for audit rule struct
5020  *
5021  * Allocate and initialize an LSM audit rule structure.
5022  *
5023  * Return: Return 0 if @lsmrule has been successfully set, -EINVAL in case of
5024  *         an invalid rule.
5025  */
5026 int security_audit_rule_init(u32 field, u32 op, char *rulestr, void **lsmrule)
5027 {
5028 	return call_int_hook(audit_rule_init, 0, field, op, rulestr, lsmrule);
5029 }
5030 
5031 /**
5032  * security_audit_rule_known() - Check if an audit rule contains LSM fields
5033  * @krule: audit rule
5034  *
5035  * Specifies whether given @krule contains any fields related to the current
5036  * LSM.
5037  *
5038  * Return: Returns 1 in case of relation found, 0 otherwise.
5039  */
5040 int security_audit_rule_known(struct audit_krule *krule)
5041 {
5042 	return call_int_hook(audit_rule_known, 0, krule);
5043 }
5044 
5045 /**
5046  * security_audit_rule_free() - Free an LSM audit rule struct
5047  * @lsmrule: audit rule struct
5048  *
5049  * Deallocate the LSM audit rule structure previously allocated by
5050  * audit_rule_init().
5051  */
5052 void security_audit_rule_free(void *lsmrule)
5053 {
5054 	call_void_hook(audit_rule_free, lsmrule);
5055 }
5056 
5057 /**
5058  * security_audit_rule_match() - Check if a label matches an audit rule
5059  * @secid: security label
5060  * @field: LSM audit field
5061  * @op: matching operator
5062  * @lsmrule: audit rule
5063  *
5064  * Determine if given @secid matches a rule previously approved by
5065  * security_audit_rule_known().
5066  *
5067  * Return: Returns 1 if secid matches the rule, 0 if it does not, -ERRNO on
5068  *         failure.
5069  */
5070 int security_audit_rule_match(u32 secid, u32 field, u32 op, void *lsmrule)
5071 {
5072 	return call_int_hook(audit_rule_match, 0, secid, field, op, lsmrule);
5073 }
5074 #endif /* CONFIG_AUDIT */
5075 
5076 #ifdef CONFIG_BPF_SYSCALL
5077 /**
5078  * security_bpf() - Check if the bpf syscall operation is allowed
5079  * @cmd: command
5080  * @attr: bpf attribute
5081  * @size: size
5082  *
5083  * Do a initial check for all bpf syscalls after the attribute is copied into
5084  * the kernel. The actual security module can implement their own rules to
5085  * check the specific cmd they need.
5086  *
5087  * Return: Returns 0 if permission is granted.
5088  */
5089 int security_bpf(int cmd, union bpf_attr *attr, unsigned int size)
5090 {
5091 	return call_int_hook(bpf, 0, cmd, attr, size);
5092 }
5093 
5094 /**
5095  * security_bpf_map() - Check if access to a bpf map is allowed
5096  * @map: bpf map
5097  * @fmode: mode
5098  *
5099  * Do a check when the kernel generates and returns a file descriptor for eBPF
5100  * maps.
5101  *
5102  * Return: Returns 0 if permission is granted.
5103  */
5104 int security_bpf_map(struct bpf_map *map, fmode_t fmode)
5105 {
5106 	return call_int_hook(bpf_map, 0, map, fmode);
5107 }
5108 
5109 /**
5110  * security_bpf_prog() - Check if access to a bpf program is allowed
5111  * @prog: bpf program
5112  *
5113  * Do a check when the kernel generates and returns a file descriptor for eBPF
5114  * programs.
5115  *
5116  * Return: Returns 0 if permission is granted.
5117  */
5118 int security_bpf_prog(struct bpf_prog *prog)
5119 {
5120 	return call_int_hook(bpf_prog, 0, prog);
5121 }
5122 
5123 /**
5124  * security_bpf_map_alloc() - Allocate a bpf map LSM blob
5125  * @map: bpf map
5126  *
5127  * Initialize the security field inside bpf map.
5128  *
5129  * Return: Returns 0 on success, error on failure.
5130  */
5131 int security_bpf_map_alloc(struct bpf_map *map)
5132 {
5133 	return call_int_hook(bpf_map_alloc_security, 0, map);
5134 }
5135 
5136 /**
5137  * security_bpf_prog_alloc() - Allocate a bpf program LSM blob
5138  * @aux: bpf program aux info struct
5139  *
5140  * Initialize the security field inside bpf program.
5141  *
5142  * Return: Returns 0 on success, error on failure.
5143  */
5144 int security_bpf_prog_alloc(struct bpf_prog_aux *aux)
5145 {
5146 	return call_int_hook(bpf_prog_alloc_security, 0, aux);
5147 }
5148 
5149 /**
5150  * security_bpf_map_free() - Free a bpf map's LSM blob
5151  * @map: bpf map
5152  *
5153  * Clean up the security information stored inside bpf map.
5154  */
5155 void security_bpf_map_free(struct bpf_map *map)
5156 {
5157 	call_void_hook(bpf_map_free_security, map);
5158 }
5159 
5160 /**
5161  * security_bpf_prog_free() - Free a bpf program's LSM blob
5162  * @aux: bpf program aux info struct
5163  *
5164  * Clean up the security information stored inside bpf prog.
5165  */
5166 void security_bpf_prog_free(struct bpf_prog_aux *aux)
5167 {
5168 	call_void_hook(bpf_prog_free_security, aux);
5169 }
5170 #endif /* CONFIG_BPF_SYSCALL */
5171 
5172 /**
5173  * security_locked_down() - Check if a kernel feature is allowed
5174  * @what: requested kernel feature
5175  *
5176  * Determine whether a kernel feature that potentially enables arbitrary code
5177  * execution in kernel space should be permitted.
5178  *
5179  * Return: Returns 0 if permission is granted.
5180  */
5181 int security_locked_down(enum lockdown_reason what)
5182 {
5183 	return call_int_hook(locked_down, 0, what);
5184 }
5185 EXPORT_SYMBOL(security_locked_down);
5186 
5187 #ifdef CONFIG_PERF_EVENTS
5188 /**
5189  * security_perf_event_open() - Check if a perf event open is allowed
5190  * @attr: perf event attribute
5191  * @type: type of event
5192  *
5193  * Check whether the @type of perf_event_open syscall is allowed.
5194  *
5195  * Return: Returns 0 if permission is granted.
5196  */
5197 int security_perf_event_open(struct perf_event_attr *attr, int type)
5198 {
5199 	return call_int_hook(perf_event_open, 0, attr, type);
5200 }
5201 
5202 /**
5203  * security_perf_event_alloc() - Allocate a perf event LSM blob
5204  * @event: perf event
5205  *
5206  * Allocate and save perf_event security info.
5207  *
5208  * Return: Returns 0 on success, error on failure.
5209  */
5210 int security_perf_event_alloc(struct perf_event *event)
5211 {
5212 	return call_int_hook(perf_event_alloc, 0, event);
5213 }
5214 
5215 /**
5216  * security_perf_event_free() - Free a perf event LSM blob
5217  * @event: perf event
5218  *
5219  * Release (free) perf_event security info.
5220  */
5221 void security_perf_event_free(struct perf_event *event)
5222 {
5223 	call_void_hook(perf_event_free, event);
5224 }
5225 
5226 /**
5227  * security_perf_event_read() - Check if reading a perf event label is allowed
5228  * @event: perf event
5229  *
5230  * Read perf_event security info if allowed.
5231  *
5232  * Return: Returns 0 if permission is granted.
5233  */
5234 int security_perf_event_read(struct perf_event *event)
5235 {
5236 	return call_int_hook(perf_event_read, 0, event);
5237 }
5238 
5239 /**
5240  * security_perf_event_write() - Check if writing a perf event label is allowed
5241  * @event: perf event
5242  *
5243  * Write perf_event security info if allowed.
5244  *
5245  * Return: Returns 0 if permission is granted.
5246  */
5247 int security_perf_event_write(struct perf_event *event)
5248 {
5249 	return call_int_hook(perf_event_write, 0, event);
5250 }
5251 #endif /* CONFIG_PERF_EVENTS */
5252 
5253 #ifdef CONFIG_IO_URING
5254 /**
5255  * security_uring_override_creds() - Check if overriding creds is allowed
5256  * @new: new credentials
5257  *
5258  * Check if the current task, executing an io_uring operation, is allowed to
5259  * override it's credentials with @new.
5260  *
5261  * Return: Returns 0 if permission is granted.
5262  */
5263 int security_uring_override_creds(const struct cred *new)
5264 {
5265 	return call_int_hook(uring_override_creds, 0, new);
5266 }
5267 
5268 /**
5269  * security_uring_sqpoll() - Check if IORING_SETUP_SQPOLL is allowed
5270  *
5271  * Check whether the current task is allowed to spawn a io_uring polling thread
5272  * (IORING_SETUP_SQPOLL).
5273  *
5274  * Return: Returns 0 if permission is granted.
5275  */
5276 int security_uring_sqpoll(void)
5277 {
5278 	return call_int_hook(uring_sqpoll, 0);
5279 }
5280 
5281 /**
5282  * security_uring_cmd() - Check if a io_uring passthrough command is allowed
5283  * @ioucmd: command
5284  *
5285  * Check whether the file_operations uring_cmd is allowed to run.
5286  *
5287  * Return: Returns 0 if permission is granted.
5288  */
5289 int security_uring_cmd(struct io_uring_cmd *ioucmd)
5290 {
5291 	return call_int_hook(uring_cmd, 0, ioucmd);
5292 }
5293 #endif /* CONFIG_IO_URING */
5294