1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Security plug functions
4  *
5  * Copyright (C) 2001 WireX Communications, Inc <chris@wirex.com>
6  * Copyright (C) 2001-2002 Greg Kroah-Hartman <greg@kroah.com>
7  * Copyright (C) 2001 Networks Associates Technology, Inc <ssmalley@nai.com>
8  * Copyright (C) 2016 Mellanox Technologies
9  * Copyright (C) 2023 Microsoft Corporation <paul@paul-moore.com>
10  */
11 
12 #define pr_fmt(fmt) "LSM: " fmt
13 
14 #include <linux/bpf.h>
15 #include <linux/capability.h>
16 #include <linux/dcache.h>
17 #include <linux/export.h>
18 #include <linux/init.h>
19 #include <linux/kernel.h>
20 #include <linux/kernel_read_file.h>
21 #include <linux/lsm_hooks.h>
22 #include <linux/fsnotify.h>
23 #include <linux/mman.h>
24 #include <linux/mount.h>
25 #include <linux/personality.h>
26 #include <linux/backing-dev.h>
27 #include <linux/string.h>
28 #include <linux/xattr.h>
29 #include <linux/msg.h>
30 #include <linux/overflow.h>
31 #include <linux/perf_event.h>
32 #include <linux/fs.h>
33 #include <net/flow.h>
34 #include <net/sock.h>
35 
36 #define SECURITY_HOOK_ACTIVE_KEY(HOOK, IDX) security_hook_active_##HOOK##_##IDX
37 
38 /*
39  * Identifier for the LSM static calls.
40  * HOOK is an LSM hook as defined in linux/lsm_hookdefs.h
41  * IDX is the index of the static call. 0 <= NUM < MAX_LSM_COUNT
42  */
43 #define LSM_STATIC_CALL(HOOK, IDX) lsm_static_call_##HOOK##_##IDX
44 
45 /*
46  * Call the macro M for each LSM hook MAX_LSM_COUNT times.
47  */
48 #define LSM_LOOP_UNROLL(M, ...) 		\
49 do {						\
50 	UNROLL(MAX_LSM_COUNT, M, __VA_ARGS__)	\
51 } while (0)
52 
53 #define LSM_DEFINE_UNROLL(M, ...) UNROLL(MAX_LSM_COUNT, M, __VA_ARGS__)
54 
55 /*
56  * These are descriptions of the reasons that can be passed to the
57  * security_locked_down() LSM hook. Placing this array here allows
58  * all security modules to use the same descriptions for auditing
59  * purposes.
60  */
61 const char *const lockdown_reasons[LOCKDOWN_CONFIDENTIALITY_MAX + 1] = {
62 	[LOCKDOWN_NONE] = "none",
63 	[LOCKDOWN_MODULE_SIGNATURE] = "unsigned module loading",
64 	[LOCKDOWN_DEV_MEM] = "/dev/mem,kmem,port",
65 	[LOCKDOWN_EFI_TEST] = "/dev/efi_test access",
66 	[LOCKDOWN_KEXEC] = "kexec of unsigned images",
67 	[LOCKDOWN_HIBERNATION] = "hibernation",
68 	[LOCKDOWN_PCI_ACCESS] = "direct PCI access",
69 	[LOCKDOWN_IOPORT] = "raw io port access",
70 	[LOCKDOWN_MSR] = "raw MSR access",
71 	[LOCKDOWN_ACPI_TABLES] = "modifying ACPI tables",
72 	[LOCKDOWN_DEVICE_TREE] = "modifying device tree contents",
73 	[LOCKDOWN_PCMCIA_CIS] = "direct PCMCIA CIS storage",
74 	[LOCKDOWN_TIOCSSERIAL] = "reconfiguration of serial port IO",
75 	[LOCKDOWN_MODULE_PARAMETERS] = "unsafe module parameters",
76 	[LOCKDOWN_MMIOTRACE] = "unsafe mmio",
77 	[LOCKDOWN_DEBUGFS] = "debugfs access",
78 	[LOCKDOWN_XMON_WR] = "xmon write access",
79 	[LOCKDOWN_BPF_WRITE_USER] = "use of bpf to write user RAM",
80 	[LOCKDOWN_DBG_WRITE_KERNEL] = "use of kgdb/kdb to write kernel RAM",
81 	[LOCKDOWN_RTAS_ERROR_INJECTION] = "RTAS error injection",
82 	[LOCKDOWN_INTEGRITY_MAX] = "integrity",
83 	[LOCKDOWN_KCORE] = "/proc/kcore access",
84 	[LOCKDOWN_KPROBES] = "use of kprobes",
85 	[LOCKDOWN_BPF_READ_KERNEL] = "use of bpf to read kernel RAM",
86 	[LOCKDOWN_DBG_READ_KERNEL] = "use of kgdb/kdb to read kernel RAM",
87 	[LOCKDOWN_PERF] = "unsafe use of perf",
88 	[LOCKDOWN_TRACEFS] = "use of tracefs",
89 	[LOCKDOWN_XMON_RW] = "xmon read and write access",
90 	[LOCKDOWN_XFRM_SECRET] = "xfrm SA secret",
91 	[LOCKDOWN_CONFIDENTIALITY_MAX] = "confidentiality",
92 };
93 
94 static BLOCKING_NOTIFIER_HEAD(blocking_lsm_notifier_chain);
95 
96 static struct kmem_cache *lsm_file_cache;
97 static struct kmem_cache *lsm_inode_cache;
98 
99 char *lsm_names;
100 static struct lsm_blob_sizes blob_sizes __ro_after_init;
101 
102 /* Boot-time LSM user choice */
103 static __initdata const char *chosen_lsm_order;
104 static __initdata const char *chosen_major_lsm;
105 
106 static __initconst const char *const builtin_lsm_order = CONFIG_LSM;
107 
108 /* Ordered list of LSMs to initialize. */
109 static __initdata struct lsm_info *ordered_lsms[MAX_LSM_COUNT + 1];
110 static __initdata struct lsm_info *exclusive;
111 
112 #ifdef CONFIG_HAVE_STATIC_CALL
113 #define LSM_HOOK_TRAMP(NAME, NUM) \
114 	&STATIC_CALL_TRAMP(LSM_STATIC_CALL(NAME, NUM))
115 #else
116 #define LSM_HOOK_TRAMP(NAME, NUM) NULL
117 #endif
118 
119 /*
120  * Define static calls and static keys for each LSM hook.
121  */
122 #define DEFINE_LSM_STATIC_CALL(NUM, NAME, RET, ...)			\
123 	DEFINE_STATIC_CALL_NULL(LSM_STATIC_CALL(NAME, NUM),		\
124 				*((RET(*)(__VA_ARGS__))NULL));		\
125 	DEFINE_STATIC_KEY_FALSE(SECURITY_HOOK_ACTIVE_KEY(NAME, NUM));
126 
127 #define LSM_HOOK(RET, DEFAULT, NAME, ...)				\
128 	LSM_DEFINE_UNROLL(DEFINE_LSM_STATIC_CALL, NAME, RET, __VA_ARGS__)
129 #include <linux/lsm_hook_defs.h>
130 #undef LSM_HOOK
131 #undef DEFINE_LSM_STATIC_CALL
132 
133 /*
134  * Initialise a table of static calls for each LSM hook.
135  * DEFINE_STATIC_CALL_NULL invocation above generates a key (STATIC_CALL_KEY)
136  * and a trampoline (STATIC_CALL_TRAMP) which are used to call
137  * __static_call_update when updating the static call.
138  *
139  * The static calls table is used by early LSMs, some architectures can fault on
140  * unaligned accesses and the fault handling code may not be ready by then.
141  * Thus, the static calls table should be aligned to avoid any unhandled faults
142  * in early init.
143  */
144 struct lsm_static_calls_table
145 	static_calls_table __ro_after_init __aligned(sizeof(u64)) = {
146 #define INIT_LSM_STATIC_CALL(NUM, NAME)					\
147 	(struct lsm_static_call) {					\
148 		.key = &STATIC_CALL_KEY(LSM_STATIC_CALL(NAME, NUM)),	\
149 		.trampoline = LSM_HOOK_TRAMP(NAME, NUM),		\
150 		.active = &SECURITY_HOOK_ACTIVE_KEY(NAME, NUM),		\
151 	},
152 #define LSM_HOOK(RET, DEFAULT, NAME, ...)				\
153 	.NAME = {							\
154 		LSM_DEFINE_UNROLL(INIT_LSM_STATIC_CALL, NAME)		\
155 	},
156 #include <linux/lsm_hook_defs.h>
157 #undef LSM_HOOK
158 #undef INIT_LSM_STATIC_CALL
159 	};
160 
161 static __initdata bool debug;
162 #define init_debug(...)						\
163 	do {							\
164 		if (debug)					\
165 			pr_info(__VA_ARGS__);			\
166 	} while (0)
167 
is_enabled(struct lsm_info * lsm)168 static bool __init is_enabled(struct lsm_info *lsm)
169 {
170 	if (!lsm->enabled)
171 		return false;
172 
173 	return *lsm->enabled;
174 }
175 
176 /* Mark an LSM's enabled flag. */
177 static int lsm_enabled_true __initdata = 1;
178 static int lsm_enabled_false __initdata = 0;
set_enabled(struct lsm_info * lsm,bool enabled)179 static void __init set_enabled(struct lsm_info *lsm, bool enabled)
180 {
181 	/*
182 	 * When an LSM hasn't configured an enable variable, we can use
183 	 * a hard-coded location for storing the default enabled state.
184 	 */
185 	if (!lsm->enabled) {
186 		if (enabled)
187 			lsm->enabled = &lsm_enabled_true;
188 		else
189 			lsm->enabled = &lsm_enabled_false;
190 	} else if (lsm->enabled == &lsm_enabled_true) {
191 		if (!enabled)
192 			lsm->enabled = &lsm_enabled_false;
193 	} else if (lsm->enabled == &lsm_enabled_false) {
194 		if (enabled)
195 			lsm->enabled = &lsm_enabled_true;
196 	} else {
197 		*lsm->enabled = enabled;
198 	}
199 }
200 
201 /* Is an LSM already listed in the ordered LSMs list? */
exists_ordered_lsm(struct lsm_info * lsm)202 static bool __init exists_ordered_lsm(struct lsm_info *lsm)
203 {
204 	struct lsm_info **check;
205 
206 	for (check = ordered_lsms; *check; check++)
207 		if (*check == lsm)
208 			return true;
209 
210 	return false;
211 }
212 
213 /* Append an LSM to the list of ordered LSMs to initialize. */
214 static int last_lsm __initdata;
append_ordered_lsm(struct lsm_info * lsm,const char * from)215 static void __init append_ordered_lsm(struct lsm_info *lsm, const char *from)
216 {
217 	/* Ignore duplicate selections. */
218 	if (exists_ordered_lsm(lsm))
219 		return;
220 
221 	if (WARN(last_lsm == MAX_LSM_COUNT, "%s: out of LSM static calls!?\n", from))
222 		return;
223 
224 	/* Enable this LSM, if it is not already set. */
225 	if (!lsm->enabled)
226 		lsm->enabled = &lsm_enabled_true;
227 	ordered_lsms[last_lsm++] = lsm;
228 
229 	init_debug("%s ordered: %s (%s)\n", from, lsm->name,
230 		   is_enabled(lsm) ? "enabled" : "disabled");
231 }
232 
233 /* Is an LSM allowed to be initialized? */
lsm_allowed(struct lsm_info * lsm)234 static bool __init lsm_allowed(struct lsm_info *lsm)
235 {
236 	/* Skip if the LSM is disabled. */
237 	if (!is_enabled(lsm))
238 		return false;
239 
240 	/* Not allowed if another exclusive LSM already initialized. */
241 	if ((lsm->flags & LSM_FLAG_EXCLUSIVE) && exclusive) {
242 		init_debug("exclusive disabled: %s\n", lsm->name);
243 		return false;
244 	}
245 
246 	return true;
247 }
248 
lsm_set_blob_size(int * need,int * lbs)249 static void __init lsm_set_blob_size(int *need, int *lbs)
250 {
251 	int offset;
252 
253 	if (*need <= 0)
254 		return;
255 
256 	offset = ALIGN(*lbs, sizeof(void *));
257 	*lbs = offset + *need;
258 	*need = offset;
259 }
260 
lsm_set_blob_sizes(struct lsm_blob_sizes * needed)261 static void __init lsm_set_blob_sizes(struct lsm_blob_sizes *needed)
262 {
263 	if (!needed)
264 		return;
265 
266 	lsm_set_blob_size(&needed->lbs_cred, &blob_sizes.lbs_cred);
267 	lsm_set_blob_size(&needed->lbs_file, &blob_sizes.lbs_file);
268 	lsm_set_blob_size(&needed->lbs_ib, &blob_sizes.lbs_ib);
269 	/*
270 	 * The inode blob gets an rcu_head in addition to
271 	 * what the modules might need.
272 	 */
273 	if (needed->lbs_inode && blob_sizes.lbs_inode == 0)
274 		blob_sizes.lbs_inode = sizeof(struct rcu_head);
275 	lsm_set_blob_size(&needed->lbs_inode, &blob_sizes.lbs_inode);
276 	lsm_set_blob_size(&needed->lbs_ipc, &blob_sizes.lbs_ipc);
277 	lsm_set_blob_size(&needed->lbs_key, &blob_sizes.lbs_key);
278 	lsm_set_blob_size(&needed->lbs_msg_msg, &blob_sizes.lbs_msg_msg);
279 	lsm_set_blob_size(&needed->lbs_perf_event, &blob_sizes.lbs_perf_event);
280 	lsm_set_blob_size(&needed->lbs_sock, &blob_sizes.lbs_sock);
281 	lsm_set_blob_size(&needed->lbs_superblock, &blob_sizes.lbs_superblock);
282 	lsm_set_blob_size(&needed->lbs_task, &blob_sizes.lbs_task);
283 	lsm_set_blob_size(&needed->lbs_tun_dev, &blob_sizes.lbs_tun_dev);
284 	lsm_set_blob_size(&needed->lbs_xattr_count,
285 			  &blob_sizes.lbs_xattr_count);
286 	lsm_set_blob_size(&needed->lbs_bdev, &blob_sizes.lbs_bdev);
287 }
288 
289 /* Prepare LSM for initialization. */
prepare_lsm(struct lsm_info * lsm)290 static void __init prepare_lsm(struct lsm_info *lsm)
291 {
292 	int enabled = lsm_allowed(lsm);
293 
294 	/* Record enablement (to handle any following exclusive LSMs). */
295 	set_enabled(lsm, enabled);
296 
297 	/* If enabled, do pre-initialization work. */
298 	if (enabled) {
299 		if ((lsm->flags & LSM_FLAG_EXCLUSIVE) && !exclusive) {
300 			exclusive = lsm;
301 			init_debug("exclusive chosen:   %s\n", lsm->name);
302 		}
303 
304 		lsm_set_blob_sizes(lsm->blobs);
305 	}
306 }
307 
308 /* Initialize a given LSM, if it is enabled. */
initialize_lsm(struct lsm_info * lsm)309 static void __init initialize_lsm(struct lsm_info *lsm)
310 {
311 	if (is_enabled(lsm)) {
312 		int ret;
313 
314 		init_debug("initializing %s\n", lsm->name);
315 		ret = lsm->init();
316 		WARN(ret, "%s failed to initialize: %d\n", lsm->name, ret);
317 	}
318 }
319 
320 /*
321  * Current index to use while initializing the lsm id list.
322  */
323 u32 lsm_active_cnt __ro_after_init;
324 const struct lsm_id *lsm_idlist[MAX_LSM_COUNT];
325 
326 /* Populate ordered LSMs list from comma-separated LSM name list. */
ordered_lsm_parse(const char * order,const char * origin)327 static void __init ordered_lsm_parse(const char *order, const char *origin)
328 {
329 	struct lsm_info *lsm;
330 	char *sep, *name, *next;
331 
332 	/* LSM_ORDER_FIRST is always first. */
333 	for (lsm = __start_lsm_info; lsm < __end_lsm_info; lsm++) {
334 		if (lsm->order == LSM_ORDER_FIRST)
335 			append_ordered_lsm(lsm, "  first");
336 	}
337 
338 	/* Process "security=", if given. */
339 	if (chosen_major_lsm) {
340 		struct lsm_info *major;
341 
342 		/*
343 		 * To match the original "security=" behavior, this
344 		 * explicitly does NOT fallback to another Legacy Major
345 		 * if the selected one was separately disabled: disable
346 		 * all non-matching Legacy Major LSMs.
347 		 */
348 		for (major = __start_lsm_info; major < __end_lsm_info;
349 		     major++) {
350 			if ((major->flags & LSM_FLAG_LEGACY_MAJOR) &&
351 			    strcmp(major->name, chosen_major_lsm) != 0) {
352 				set_enabled(major, false);
353 				init_debug("security=%s disabled: %s (only one legacy major LSM)\n",
354 					   chosen_major_lsm, major->name);
355 			}
356 		}
357 	}
358 
359 	sep = kstrdup(order, GFP_KERNEL);
360 	next = sep;
361 	/* Walk the list, looking for matching LSMs. */
362 	while ((name = strsep(&next, ",")) != NULL) {
363 		bool found = false;
364 
365 		for (lsm = __start_lsm_info; lsm < __end_lsm_info; lsm++) {
366 			if (strcmp(lsm->name, name) == 0) {
367 				if (lsm->order == LSM_ORDER_MUTABLE)
368 					append_ordered_lsm(lsm, origin);
369 				found = true;
370 			}
371 		}
372 
373 		if (!found)
374 			init_debug("%s ignored: %s (not built into kernel)\n",
375 				   origin, name);
376 	}
377 
378 	/* Process "security=", if given. */
379 	if (chosen_major_lsm) {
380 		for (lsm = __start_lsm_info; lsm < __end_lsm_info; lsm++) {
381 			if (exists_ordered_lsm(lsm))
382 				continue;
383 			if (strcmp(lsm->name, chosen_major_lsm) == 0)
384 				append_ordered_lsm(lsm, "security=");
385 		}
386 	}
387 
388 	/* LSM_ORDER_LAST is always last. */
389 	for (lsm = __start_lsm_info; lsm < __end_lsm_info; lsm++) {
390 		if (lsm->order == LSM_ORDER_LAST)
391 			append_ordered_lsm(lsm, "   last");
392 	}
393 
394 	/* Disable all LSMs not in the ordered list. */
395 	for (lsm = __start_lsm_info; lsm < __end_lsm_info; lsm++) {
396 		if (exists_ordered_lsm(lsm))
397 			continue;
398 		set_enabled(lsm, false);
399 		init_debug("%s skipped: %s (not in requested order)\n",
400 			   origin, lsm->name);
401 	}
402 
403 	kfree(sep);
404 }
405 
lsm_static_call_init(struct security_hook_list * hl)406 static void __init lsm_static_call_init(struct security_hook_list *hl)
407 {
408 	struct lsm_static_call *scall = hl->scalls;
409 	int i;
410 
411 	for (i = 0; i < MAX_LSM_COUNT; i++) {
412 		/* Update the first static call that is not used yet */
413 		if (!scall->hl) {
414 			__static_call_update(scall->key, scall->trampoline,
415 					     hl->hook.lsm_func_addr);
416 			scall->hl = hl;
417 			static_branch_enable(scall->active);
418 			return;
419 		}
420 		scall++;
421 	}
422 	panic("%s - Ran out of static slots.\n", __func__);
423 }
424 
425 static void __init lsm_early_cred(struct cred *cred);
426 static void __init lsm_early_task(struct task_struct *task);
427 
428 static int lsm_append(const char *new, char **result);
429 
report_lsm_order(void)430 static void __init report_lsm_order(void)
431 {
432 	struct lsm_info **lsm, *early;
433 	int first = 0;
434 
435 	pr_info("initializing lsm=");
436 
437 	/* Report each enabled LSM name, comma separated. */
438 	for (early = __start_early_lsm_info;
439 	     early < __end_early_lsm_info; early++)
440 		if (is_enabled(early))
441 			pr_cont("%s%s", first++ == 0 ? "" : ",", early->name);
442 	for (lsm = ordered_lsms; *lsm; lsm++)
443 		if (is_enabled(*lsm))
444 			pr_cont("%s%s", first++ == 0 ? "" : ",", (*lsm)->name);
445 
446 	pr_cont("\n");
447 }
448 
ordered_lsm_init(void)449 static void __init ordered_lsm_init(void)
450 {
451 	struct lsm_info **lsm;
452 
453 	if (chosen_lsm_order) {
454 		if (chosen_major_lsm) {
455 			pr_warn("security=%s is ignored because it is superseded by lsm=%s\n",
456 				chosen_major_lsm, chosen_lsm_order);
457 			chosen_major_lsm = NULL;
458 		}
459 		ordered_lsm_parse(chosen_lsm_order, "cmdline");
460 	} else
461 		ordered_lsm_parse(builtin_lsm_order, "builtin");
462 
463 	for (lsm = ordered_lsms; *lsm; lsm++)
464 		prepare_lsm(*lsm);
465 
466 	report_lsm_order();
467 
468 	init_debug("cred blob size       = %d\n", blob_sizes.lbs_cred);
469 	init_debug("file blob size       = %d\n", blob_sizes.lbs_file);
470 	init_debug("ib blob size         = %d\n", blob_sizes.lbs_ib);
471 	init_debug("inode blob size      = %d\n", blob_sizes.lbs_inode);
472 	init_debug("ipc blob size        = %d\n", blob_sizes.lbs_ipc);
473 #ifdef CONFIG_KEYS
474 	init_debug("key blob size        = %d\n", blob_sizes.lbs_key);
475 #endif /* CONFIG_KEYS */
476 	init_debug("msg_msg blob size    = %d\n", blob_sizes.lbs_msg_msg);
477 	init_debug("sock blob size       = %d\n", blob_sizes.lbs_sock);
478 	init_debug("superblock blob size = %d\n", blob_sizes.lbs_superblock);
479 	init_debug("perf event blob size = %d\n", blob_sizes.lbs_perf_event);
480 	init_debug("task blob size       = %d\n", blob_sizes.lbs_task);
481 	init_debug("tun device blob size = %d\n", blob_sizes.lbs_tun_dev);
482 	init_debug("xattr slots          = %d\n", blob_sizes.lbs_xattr_count);
483 	init_debug("bdev blob size       = %d\n", blob_sizes.lbs_bdev);
484 
485 	/*
486 	 * Create any kmem_caches needed for blobs
487 	 */
488 	if (blob_sizes.lbs_file)
489 		lsm_file_cache = kmem_cache_create("lsm_file_cache",
490 						   blob_sizes.lbs_file, 0,
491 						   SLAB_PANIC, NULL);
492 	if (blob_sizes.lbs_inode)
493 		lsm_inode_cache = kmem_cache_create("lsm_inode_cache",
494 						    blob_sizes.lbs_inode, 0,
495 						    SLAB_PANIC, NULL);
496 
497 	lsm_early_cred((struct cred *) current->cred);
498 	lsm_early_task(current);
499 	for (lsm = ordered_lsms; *lsm; lsm++)
500 		initialize_lsm(*lsm);
501 }
502 
early_security_init(void)503 int __init early_security_init(void)
504 {
505 	struct lsm_info *lsm;
506 
507 	for (lsm = __start_early_lsm_info; lsm < __end_early_lsm_info; lsm++) {
508 		if (!lsm->enabled)
509 			lsm->enabled = &lsm_enabled_true;
510 		prepare_lsm(lsm);
511 		initialize_lsm(lsm);
512 	}
513 
514 	return 0;
515 }
516 
517 /**
518  * security_init - initializes the security framework
519  *
520  * This should be called early in the kernel initialization sequence.
521  */
security_init(void)522 int __init security_init(void)
523 {
524 	struct lsm_info *lsm;
525 
526 	init_debug("legacy security=%s\n", chosen_major_lsm ? : " *unspecified*");
527 	init_debug("  CONFIG_LSM=%s\n", builtin_lsm_order);
528 	init_debug("boot arg lsm=%s\n", chosen_lsm_order ? : " *unspecified*");
529 
530 	/*
531 	 * Append the names of the early LSM modules now that kmalloc() is
532 	 * available
533 	 */
534 	for (lsm = __start_early_lsm_info; lsm < __end_early_lsm_info; lsm++) {
535 		init_debug("  early started: %s (%s)\n", lsm->name,
536 			   is_enabled(lsm) ? "enabled" : "disabled");
537 		if (lsm->enabled)
538 			lsm_append(lsm->name, &lsm_names);
539 	}
540 
541 	/* Load LSMs in specified order. */
542 	ordered_lsm_init();
543 
544 	return 0;
545 }
546 
547 /* Save user chosen LSM */
choose_major_lsm(char * str)548 static int __init choose_major_lsm(char *str)
549 {
550 	chosen_major_lsm = str;
551 	return 1;
552 }
553 __setup("security=", choose_major_lsm);
554 
555 /* Explicitly choose LSM initialization order. */
choose_lsm_order(char * str)556 static int __init choose_lsm_order(char *str)
557 {
558 	chosen_lsm_order = str;
559 	return 1;
560 }
561 __setup("lsm=", choose_lsm_order);
562 
563 /* Enable LSM order debugging. */
enable_debug(char * str)564 static int __init enable_debug(char *str)
565 {
566 	debug = true;
567 	return 1;
568 }
569 __setup("lsm.debug", enable_debug);
570 
match_last_lsm(const char * list,const char * lsm)571 static bool match_last_lsm(const char *list, const char *lsm)
572 {
573 	const char *last;
574 
575 	if (WARN_ON(!list || !lsm))
576 		return false;
577 	last = strrchr(list, ',');
578 	if (last)
579 		/* Pass the comma, strcmp() will check for '\0' */
580 		last++;
581 	else
582 		last = list;
583 	return !strcmp(last, lsm);
584 }
585 
lsm_append(const char * new,char ** result)586 static int lsm_append(const char *new, char **result)
587 {
588 	char *cp;
589 
590 	if (*result == NULL) {
591 		*result = kstrdup(new, GFP_KERNEL);
592 		if (*result == NULL)
593 			return -ENOMEM;
594 	} else {
595 		/* Check if it is the last registered name */
596 		if (match_last_lsm(*result, new))
597 			return 0;
598 		cp = kasprintf(GFP_KERNEL, "%s,%s", *result, new);
599 		if (cp == NULL)
600 			return -ENOMEM;
601 		kfree(*result);
602 		*result = cp;
603 	}
604 	return 0;
605 }
606 
607 /**
608  * security_add_hooks - Add a modules hooks to the hook lists.
609  * @hooks: the hooks to add
610  * @count: the number of hooks to add
611  * @lsmid: the identification information for the security module
612  *
613  * Each LSM has to register its hooks with the infrastructure.
614  */
security_add_hooks(struct security_hook_list * hooks,int count,const struct lsm_id * lsmid)615 void __init security_add_hooks(struct security_hook_list *hooks, int count,
616 			       const struct lsm_id *lsmid)
617 {
618 	int i;
619 
620 	/*
621 	 * A security module may call security_add_hooks() more
622 	 * than once during initialization, and LSM initialization
623 	 * is serialized. Landlock is one such case.
624 	 * Look at the previous entry, if there is one, for duplication.
625 	 */
626 	if (lsm_active_cnt == 0 || lsm_idlist[lsm_active_cnt - 1] != lsmid) {
627 		if (lsm_active_cnt >= MAX_LSM_COUNT)
628 			panic("%s Too many LSMs registered.\n", __func__);
629 		lsm_idlist[lsm_active_cnt++] = lsmid;
630 	}
631 
632 	for (i = 0; i < count; i++) {
633 		hooks[i].lsmid = lsmid;
634 		lsm_static_call_init(&hooks[i]);
635 	}
636 
637 	/*
638 	 * Don't try to append during early_security_init(), we'll come back
639 	 * and fix this up afterwards.
640 	 */
641 	if (slab_is_available()) {
642 		if (lsm_append(lsmid->name, &lsm_names) < 0)
643 			panic("%s - Cannot get early memory.\n", __func__);
644 	}
645 }
646 
call_blocking_lsm_notifier(enum lsm_event event,void * data)647 int call_blocking_lsm_notifier(enum lsm_event event, void *data)
648 {
649 	return blocking_notifier_call_chain(&blocking_lsm_notifier_chain,
650 					    event, data);
651 }
652 EXPORT_SYMBOL(call_blocking_lsm_notifier);
653 
register_blocking_lsm_notifier(struct notifier_block * nb)654 int register_blocking_lsm_notifier(struct notifier_block *nb)
655 {
656 	return blocking_notifier_chain_register(&blocking_lsm_notifier_chain,
657 						nb);
658 }
659 EXPORT_SYMBOL(register_blocking_lsm_notifier);
660 
unregister_blocking_lsm_notifier(struct notifier_block * nb)661 int unregister_blocking_lsm_notifier(struct notifier_block *nb)
662 {
663 	return blocking_notifier_chain_unregister(&blocking_lsm_notifier_chain,
664 						  nb);
665 }
666 EXPORT_SYMBOL(unregister_blocking_lsm_notifier);
667 
668 /**
669  * lsm_blob_alloc - allocate a composite blob
670  * @dest: the destination for the blob
671  * @size: the size of the blob
672  * @gfp: allocation type
673  *
674  * Allocate a blob for all the modules
675  *
676  * Returns 0, or -ENOMEM if memory can't be allocated.
677  */
lsm_blob_alloc(void ** dest,size_t size,gfp_t gfp)678 static int lsm_blob_alloc(void **dest, size_t size, gfp_t gfp)
679 {
680 	if (size == 0) {
681 		*dest = NULL;
682 		return 0;
683 	}
684 
685 	*dest = kzalloc(size, gfp);
686 	if (*dest == NULL)
687 		return -ENOMEM;
688 	return 0;
689 }
690 
691 /**
692  * lsm_cred_alloc - allocate a composite cred blob
693  * @cred: the cred that needs a blob
694  * @gfp: allocation type
695  *
696  * Allocate the cred blob for all the modules
697  *
698  * Returns 0, or -ENOMEM if memory can't be allocated.
699  */
lsm_cred_alloc(struct cred * cred,gfp_t gfp)700 static int lsm_cred_alloc(struct cred *cred, gfp_t gfp)
701 {
702 	return lsm_blob_alloc(&cred->security, blob_sizes.lbs_cred, gfp);
703 }
704 
705 /**
706  * lsm_early_cred - during initialization allocate a composite cred blob
707  * @cred: the cred that needs a blob
708  *
709  * Allocate the cred blob for all the modules
710  */
lsm_early_cred(struct cred * cred)711 static void __init lsm_early_cred(struct cred *cred)
712 {
713 	int rc = lsm_cred_alloc(cred, GFP_KERNEL);
714 
715 	if (rc)
716 		panic("%s: Early cred alloc failed.\n", __func__);
717 }
718 
719 /**
720  * lsm_file_alloc - allocate a composite file blob
721  * @file: the file that needs a blob
722  *
723  * Allocate the file blob for all the modules
724  *
725  * Returns 0, or -ENOMEM if memory can't be allocated.
726  */
lsm_file_alloc(struct file * file)727 static int lsm_file_alloc(struct file *file)
728 {
729 	if (!lsm_file_cache) {
730 		file->f_security = NULL;
731 		return 0;
732 	}
733 
734 	file->f_security = kmem_cache_zalloc(lsm_file_cache, GFP_KERNEL);
735 	if (file->f_security == NULL)
736 		return -ENOMEM;
737 	return 0;
738 }
739 
740 /**
741  * lsm_inode_alloc - allocate a composite inode blob
742  * @inode: the inode that needs a blob
743  * @gfp: allocation flags
744  *
745  * Allocate the inode blob for all the modules
746  *
747  * Returns 0, or -ENOMEM if memory can't be allocated.
748  */
lsm_inode_alloc(struct inode * inode,gfp_t gfp)749 static int lsm_inode_alloc(struct inode *inode, gfp_t gfp)
750 {
751 	if (!lsm_inode_cache) {
752 		inode->i_security = NULL;
753 		return 0;
754 	}
755 
756 	inode->i_security = kmem_cache_zalloc(lsm_inode_cache, gfp);
757 	if (inode->i_security == NULL)
758 		return -ENOMEM;
759 	return 0;
760 }
761 
762 /**
763  * lsm_task_alloc - allocate a composite task blob
764  * @task: the task that needs a blob
765  *
766  * Allocate the task blob for all the modules
767  *
768  * Returns 0, or -ENOMEM if memory can't be allocated.
769  */
lsm_task_alloc(struct task_struct * task)770 static int lsm_task_alloc(struct task_struct *task)
771 {
772 	return lsm_blob_alloc(&task->security, blob_sizes.lbs_task, GFP_KERNEL);
773 }
774 
775 /**
776  * lsm_ipc_alloc - allocate a composite ipc blob
777  * @kip: the ipc that needs a blob
778  *
779  * Allocate the ipc blob for all the modules
780  *
781  * Returns 0, or -ENOMEM if memory can't be allocated.
782  */
lsm_ipc_alloc(struct kern_ipc_perm * kip)783 static int lsm_ipc_alloc(struct kern_ipc_perm *kip)
784 {
785 	return lsm_blob_alloc(&kip->security, blob_sizes.lbs_ipc, GFP_KERNEL);
786 }
787 
788 #ifdef CONFIG_KEYS
789 /**
790  * lsm_key_alloc - allocate a composite key blob
791  * @key: the key that needs a blob
792  *
793  * Allocate the key blob for all the modules
794  *
795  * Returns 0, or -ENOMEM if memory can't be allocated.
796  */
lsm_key_alloc(struct key * key)797 static int lsm_key_alloc(struct key *key)
798 {
799 	return lsm_blob_alloc(&key->security, blob_sizes.lbs_key, GFP_KERNEL);
800 }
801 #endif /* CONFIG_KEYS */
802 
803 /**
804  * lsm_msg_msg_alloc - allocate a composite msg_msg blob
805  * @mp: the msg_msg that needs a blob
806  *
807  * Allocate the ipc blob for all the modules
808  *
809  * Returns 0, or -ENOMEM if memory can't be allocated.
810  */
lsm_msg_msg_alloc(struct msg_msg * mp)811 static int lsm_msg_msg_alloc(struct msg_msg *mp)
812 {
813 	return lsm_blob_alloc(&mp->security, blob_sizes.lbs_msg_msg,
814 			      GFP_KERNEL);
815 }
816 
817 /**
818  * lsm_bdev_alloc - allocate a composite block_device blob
819  * @bdev: the block_device that needs a blob
820  *
821  * Allocate the block_device blob for all the modules
822  *
823  * Returns 0, or -ENOMEM if memory can't be allocated.
824  */
lsm_bdev_alloc(struct block_device * bdev)825 static int lsm_bdev_alloc(struct block_device *bdev)
826 {
827 	if (blob_sizes.lbs_bdev == 0) {
828 		bdev->bd_security = NULL;
829 		return 0;
830 	}
831 
832 	bdev->bd_security = kzalloc(blob_sizes.lbs_bdev, GFP_KERNEL);
833 	if (!bdev->bd_security)
834 		return -ENOMEM;
835 
836 	return 0;
837 }
838 
839 /**
840  * lsm_early_task - during initialization allocate a composite task blob
841  * @task: the task that needs a blob
842  *
843  * Allocate the task blob for all the modules
844  */
lsm_early_task(struct task_struct * task)845 static void __init lsm_early_task(struct task_struct *task)
846 {
847 	int rc = lsm_task_alloc(task);
848 
849 	if (rc)
850 		panic("%s: Early task alloc failed.\n", __func__);
851 }
852 
853 /**
854  * lsm_superblock_alloc - allocate a composite superblock blob
855  * @sb: the superblock that needs a blob
856  *
857  * Allocate the superblock blob for all the modules
858  *
859  * Returns 0, or -ENOMEM if memory can't be allocated.
860  */
lsm_superblock_alloc(struct super_block * sb)861 static int lsm_superblock_alloc(struct super_block *sb)
862 {
863 	return lsm_blob_alloc(&sb->s_security, blob_sizes.lbs_superblock,
864 			      GFP_KERNEL);
865 }
866 
867 /**
868  * lsm_fill_user_ctx - Fill a user space lsm_ctx structure
869  * @uctx: a userspace LSM context to be filled
870  * @uctx_len: available uctx size (input), used uctx size (output)
871  * @val: the new LSM context value
872  * @val_len: the size of the new LSM context value
873  * @id: LSM id
874  * @flags: LSM defined flags
875  *
876  * Fill all of the fields in a userspace lsm_ctx structure.  If @uctx is NULL
877  * simply calculate the required size to output via @utc_len and return
878  * success.
879  *
880  * Returns 0 on success, -E2BIG if userspace buffer is not large enough,
881  * -EFAULT on a copyout error, -ENOMEM if memory can't be allocated.
882  */
lsm_fill_user_ctx(struct lsm_ctx __user * uctx,u32 * uctx_len,void * val,size_t val_len,u64 id,u64 flags)883 int lsm_fill_user_ctx(struct lsm_ctx __user *uctx, u32 *uctx_len,
884 		      void *val, size_t val_len,
885 		      u64 id, u64 flags)
886 {
887 	struct lsm_ctx *nctx = NULL;
888 	size_t nctx_len;
889 	int rc = 0;
890 
891 	nctx_len = ALIGN(struct_size(nctx, ctx, val_len), sizeof(void *));
892 	if (nctx_len > *uctx_len) {
893 		rc = -E2BIG;
894 		goto out;
895 	}
896 
897 	/* no buffer - return success/0 and set @uctx_len to the req size */
898 	if (!uctx)
899 		goto out;
900 
901 	nctx = kzalloc(nctx_len, GFP_KERNEL);
902 	if (nctx == NULL) {
903 		rc = -ENOMEM;
904 		goto out;
905 	}
906 	nctx->id = id;
907 	nctx->flags = flags;
908 	nctx->len = nctx_len;
909 	nctx->ctx_len = val_len;
910 	memcpy(nctx->ctx, val, val_len);
911 
912 	if (copy_to_user(uctx, nctx, nctx_len))
913 		rc = -EFAULT;
914 
915 out:
916 	kfree(nctx);
917 	*uctx_len = nctx_len;
918 	return rc;
919 }
920 
921 /*
922  * The default value of the LSM hook is defined in linux/lsm_hook_defs.h and
923  * can be accessed with:
924  *
925  *	LSM_RET_DEFAULT(<hook_name>)
926  *
927  * The macros below define static constants for the default value of each
928  * LSM hook.
929  */
930 #define LSM_RET_DEFAULT(NAME) (NAME##_default)
931 #define DECLARE_LSM_RET_DEFAULT_void(DEFAULT, NAME)
932 #define DECLARE_LSM_RET_DEFAULT_int(DEFAULT, NAME) \
933 	static const int __maybe_unused LSM_RET_DEFAULT(NAME) = (DEFAULT);
934 #define LSM_HOOK(RET, DEFAULT, NAME, ...) \
935 	DECLARE_LSM_RET_DEFAULT_##RET(DEFAULT, NAME)
936 
937 #include <linux/lsm_hook_defs.h>
938 #undef LSM_HOOK
939 
940 /*
941  * Hook list operation macros.
942  *
943  * call_void_hook:
944  *	This is a hook that does not return a value.
945  *
946  * call_int_hook:
947  *	This is a hook that returns a value.
948  */
949 #define __CALL_STATIC_VOID(NUM, HOOK, ...)				     \
950 do {									     \
951 	if (static_branch_unlikely(&SECURITY_HOOK_ACTIVE_KEY(HOOK, NUM))) {    \
952 		static_call(LSM_STATIC_CALL(HOOK, NUM))(__VA_ARGS__);	     \
953 	}								     \
954 } while (0);
955 
956 #define call_void_hook(HOOK, ...)                                 \
957 	do {                                                      \
958 		LSM_LOOP_UNROLL(__CALL_STATIC_VOID, HOOK, __VA_ARGS__); \
959 	} while (0)
960 
961 
962 #define __CALL_STATIC_INT(NUM, R, HOOK, LABEL, ...)			     \
963 do {									     \
964 	if (static_branch_unlikely(&SECURITY_HOOK_ACTIVE_KEY(HOOK, NUM))) {  \
965 		R = static_call(LSM_STATIC_CALL(HOOK, NUM))(__VA_ARGS__);    \
966 		if (R != LSM_RET_DEFAULT(HOOK))				     \
967 			goto LABEL;					     \
968 	}								     \
969 } while (0);
970 
971 #define call_int_hook(HOOK, ...)					\
972 ({									\
973 	__label__ OUT;							\
974 	int RC = LSM_RET_DEFAULT(HOOK);					\
975 									\
976 	LSM_LOOP_UNROLL(__CALL_STATIC_INT, RC, HOOK, OUT, __VA_ARGS__);	\
977 OUT:									\
978 	RC;								\
979 })
980 
981 #define lsm_for_each_hook(scall, NAME)					\
982 	for (scall = static_calls_table.NAME;				\
983 	     scall - static_calls_table.NAME < MAX_LSM_COUNT; scall++)  \
984 		if (static_key_enabled(&scall->active->key))
985 
986 /* Security operations */
987 
988 /**
989  * security_binder_set_context_mgr() - Check if becoming binder ctx mgr is ok
990  * @mgr: task credentials of current binder process
991  *
992  * Check whether @mgr is allowed to be the binder context manager.
993  *
994  * Return: Return 0 if permission is granted.
995  */
security_binder_set_context_mgr(const struct cred * mgr)996 int security_binder_set_context_mgr(const struct cred *mgr)
997 {
998 	return call_int_hook(binder_set_context_mgr, mgr);
999 }
1000 
1001 /**
1002  * security_binder_transaction() - Check if a binder transaction is allowed
1003  * @from: sending process
1004  * @to: receiving process
1005  *
1006  * Check whether @from is allowed to invoke a binder transaction call to @to.
1007  *
1008  * Return: Returns 0 if permission is granted.
1009  */
security_binder_transaction(const struct cred * from,const struct cred * to)1010 int security_binder_transaction(const struct cred *from,
1011 				const struct cred *to)
1012 {
1013 	return call_int_hook(binder_transaction, from, to);
1014 }
1015 
1016 /**
1017  * security_binder_transfer_binder() - Check if a binder transfer is allowed
1018  * @from: sending process
1019  * @to: receiving process
1020  *
1021  * Check whether @from is allowed to transfer a binder reference to @to.
1022  *
1023  * Return: Returns 0 if permission is granted.
1024  */
security_binder_transfer_binder(const struct cred * from,const struct cred * to)1025 int security_binder_transfer_binder(const struct cred *from,
1026 				    const struct cred *to)
1027 {
1028 	return call_int_hook(binder_transfer_binder, from, to);
1029 }
1030 
1031 /**
1032  * security_binder_transfer_file() - Check if a binder file xfer is allowed
1033  * @from: sending process
1034  * @to: receiving process
1035  * @file: file being transferred
1036  *
1037  * Check whether @from is allowed to transfer @file to @to.
1038  *
1039  * Return: Returns 0 if permission is granted.
1040  */
security_binder_transfer_file(const struct cred * from,const struct cred * to,const struct file * file)1041 int security_binder_transfer_file(const struct cred *from,
1042 				  const struct cred *to, const struct file *file)
1043 {
1044 	return call_int_hook(binder_transfer_file, from, to, file);
1045 }
1046 
1047 /**
1048  * security_ptrace_access_check() - Check if tracing is allowed
1049  * @child: target process
1050  * @mode: PTRACE_MODE flags
1051  *
1052  * Check permission before allowing the current process to trace the @child
1053  * process.  Security modules may also want to perform a process tracing check
1054  * during an execve in the set_security or apply_creds hooks of tracing check
1055  * during an execve in the bprm_set_creds hook of binprm_security_ops if the
1056  * process is being traced and its security attributes would be changed by the
1057  * execve.
1058  *
1059  * Return: Returns 0 if permission is granted.
1060  */
security_ptrace_access_check(struct task_struct * child,unsigned int mode)1061 int security_ptrace_access_check(struct task_struct *child, unsigned int mode)
1062 {
1063 	return call_int_hook(ptrace_access_check, child, mode);
1064 }
1065 
1066 /**
1067  * security_ptrace_traceme() - Check if tracing is allowed
1068  * @parent: tracing process
1069  *
1070  * Check that the @parent process has sufficient permission to trace the
1071  * current process before allowing the current process to present itself to the
1072  * @parent process for tracing.
1073  *
1074  * Return: Returns 0 if permission is granted.
1075  */
security_ptrace_traceme(struct task_struct * parent)1076 int security_ptrace_traceme(struct task_struct *parent)
1077 {
1078 	return call_int_hook(ptrace_traceme, parent);
1079 }
1080 
1081 /**
1082  * security_capget() - Get the capability sets for a process
1083  * @target: target process
1084  * @effective: effective capability set
1085  * @inheritable: inheritable capability set
1086  * @permitted: permitted capability set
1087  *
1088  * Get the @effective, @inheritable, and @permitted capability sets for the
1089  * @target process.  The hook may also perform permission checking to determine
1090  * if the current process is allowed to see the capability sets of the @target
1091  * process.
1092  *
1093  * Return: Returns 0 if the capability sets were successfully obtained.
1094  */
security_capget(const struct task_struct * target,kernel_cap_t * effective,kernel_cap_t * inheritable,kernel_cap_t * permitted)1095 int security_capget(const struct task_struct *target,
1096 		    kernel_cap_t *effective,
1097 		    kernel_cap_t *inheritable,
1098 		    kernel_cap_t *permitted)
1099 {
1100 	return call_int_hook(capget, target, effective, inheritable, permitted);
1101 }
1102 
1103 /**
1104  * security_capset() - Set the capability sets for a process
1105  * @new: new credentials for the target process
1106  * @old: current credentials of the target process
1107  * @effective: effective capability set
1108  * @inheritable: inheritable capability set
1109  * @permitted: permitted capability set
1110  *
1111  * Set the @effective, @inheritable, and @permitted capability sets for the
1112  * current process.
1113  *
1114  * Return: Returns 0 and update @new if permission is granted.
1115  */
security_capset(struct cred * new,const struct cred * old,const kernel_cap_t * effective,const kernel_cap_t * inheritable,const kernel_cap_t * permitted)1116 int security_capset(struct cred *new, const struct cred *old,
1117 		    const kernel_cap_t *effective,
1118 		    const kernel_cap_t *inheritable,
1119 		    const kernel_cap_t *permitted)
1120 {
1121 	return call_int_hook(capset, new, old, effective, inheritable,
1122 			     permitted);
1123 }
1124 
1125 /**
1126  * security_capable() - Check if a process has the necessary capability
1127  * @cred: credentials to examine
1128  * @ns: user namespace
1129  * @cap: capability requested
1130  * @opts: capability check options
1131  *
1132  * Check whether the @tsk process has the @cap capability in the indicated
1133  * credentials.  @cap contains the capability <include/linux/capability.h>.
1134  * @opts contains options for the capable check <include/linux/security.h>.
1135  *
1136  * Return: Returns 0 if the capability is granted.
1137  */
security_capable(const struct cred * cred,struct user_namespace * ns,int cap,unsigned int opts)1138 int security_capable(const struct cred *cred,
1139 		     struct user_namespace *ns,
1140 		     int cap,
1141 		     unsigned int opts)
1142 {
1143 	return call_int_hook(capable, cred, ns, cap, opts);
1144 }
1145 
1146 /**
1147  * security_quotactl() - Check if a quotactl() syscall is allowed for this fs
1148  * @cmds: commands
1149  * @type: type
1150  * @id: id
1151  * @sb: filesystem
1152  *
1153  * Check whether the quotactl syscall is allowed for this @sb.
1154  *
1155  * Return: Returns 0 if permission is granted.
1156  */
security_quotactl(int cmds,int type,int id,const struct super_block * sb)1157 int security_quotactl(int cmds, int type, int id, const struct super_block *sb)
1158 {
1159 	return call_int_hook(quotactl, cmds, type, id, sb);
1160 }
1161 
1162 /**
1163  * security_quota_on() - Check if QUOTAON is allowed for a dentry
1164  * @dentry: dentry
1165  *
1166  * Check whether QUOTAON is allowed for @dentry.
1167  *
1168  * Return: Returns 0 if permission is granted.
1169  */
security_quota_on(struct dentry * dentry)1170 int security_quota_on(struct dentry *dentry)
1171 {
1172 	return call_int_hook(quota_on, dentry);
1173 }
1174 
1175 /**
1176  * security_syslog() - Check if accessing the kernel message ring is allowed
1177  * @type: SYSLOG_ACTION_* type
1178  *
1179  * Check permission before accessing the kernel message ring or changing
1180  * logging to the console.  See the syslog(2) manual page for an explanation of
1181  * the @type values.
1182  *
1183  * Return: Return 0 if permission is granted.
1184  */
security_syslog(int type)1185 int security_syslog(int type)
1186 {
1187 	return call_int_hook(syslog, type);
1188 }
1189 
1190 /**
1191  * security_settime64() - Check if changing the system time is allowed
1192  * @ts: new time
1193  * @tz: timezone
1194  *
1195  * Check permission to change the system time, struct timespec64 is defined in
1196  * <include/linux/time64.h> and timezone is defined in <include/linux/time.h>.
1197  *
1198  * Return: Returns 0 if permission is granted.
1199  */
security_settime64(const struct timespec64 * ts,const struct timezone * tz)1200 int security_settime64(const struct timespec64 *ts, const struct timezone *tz)
1201 {
1202 	return call_int_hook(settime, ts, tz);
1203 }
1204 
1205 /**
1206  * security_vm_enough_memory_mm() - Check if allocating a new mem map is allowed
1207  * @mm: mm struct
1208  * @pages: number of pages
1209  *
1210  * Check permissions for allocating a new virtual mapping.  If all LSMs return
1211  * a positive value, __vm_enough_memory() will be called with cap_sys_admin
1212  * set. If at least one LSM returns 0 or negative, __vm_enough_memory() will be
1213  * called with cap_sys_admin cleared.
1214  *
1215  * Return: Returns 0 if permission is granted by the LSM infrastructure to the
1216  *         caller.
1217  */
security_vm_enough_memory_mm(struct mm_struct * mm,long pages)1218 int security_vm_enough_memory_mm(struct mm_struct *mm, long pages)
1219 {
1220 	struct lsm_static_call *scall;
1221 	int cap_sys_admin = 1;
1222 	int rc;
1223 
1224 	/*
1225 	 * The module will respond with 0 if it thinks the __vm_enough_memory()
1226 	 * call should be made with the cap_sys_admin set. If all of the modules
1227 	 * agree that it should be set it will. If any module thinks it should
1228 	 * not be set it won't.
1229 	 */
1230 	lsm_for_each_hook(scall, vm_enough_memory) {
1231 		rc = scall->hl->hook.vm_enough_memory(mm, pages);
1232 		if (rc < 0) {
1233 			cap_sys_admin = 0;
1234 			break;
1235 		}
1236 	}
1237 	return __vm_enough_memory(mm, pages, cap_sys_admin);
1238 }
1239 
1240 /**
1241  * security_bprm_creds_for_exec() - Prepare the credentials for exec()
1242  * @bprm: binary program information
1243  *
1244  * If the setup in prepare_exec_creds did not setup @bprm->cred->security
1245  * properly for executing @bprm->file, update the LSM's portion of
1246  * @bprm->cred->security to be what commit_creds needs to install for the new
1247  * program.  This hook may also optionally check permissions (e.g. for
1248  * transitions between security domains).  The hook must set @bprm->secureexec
1249  * to 1 if AT_SECURE should be set to request libc enable secure mode.  @bprm
1250  * contains the linux_binprm structure.
1251  *
1252  * Return: Returns 0 if the hook is successful and permission is granted.
1253  */
security_bprm_creds_for_exec(struct linux_binprm * bprm)1254 int security_bprm_creds_for_exec(struct linux_binprm *bprm)
1255 {
1256 	return call_int_hook(bprm_creds_for_exec, bprm);
1257 }
1258 
1259 /**
1260  * security_bprm_creds_from_file() - Update linux_binprm creds based on file
1261  * @bprm: binary program information
1262  * @file: associated file
1263  *
1264  * If @file is setpcap, suid, sgid or otherwise marked to change privilege upon
1265  * exec, update @bprm->cred to reflect that change. This is called after
1266  * finding the binary that will be executed without an interpreter.  This
1267  * ensures that the credentials will not be derived from a script that the
1268  * binary will need to reopen, which when reopend may end up being a completely
1269  * different file.  This hook may also optionally check permissions (e.g. for
1270  * transitions between security domains).  The hook must set @bprm->secureexec
1271  * to 1 if AT_SECURE should be set to request libc enable secure mode.  The
1272  * hook must add to @bprm->per_clear any personality flags that should be
1273  * cleared from current->personality.  @bprm contains the linux_binprm
1274  * structure.
1275  *
1276  * Return: Returns 0 if the hook is successful and permission is granted.
1277  */
security_bprm_creds_from_file(struct linux_binprm * bprm,const struct file * file)1278 int security_bprm_creds_from_file(struct linux_binprm *bprm, const struct file *file)
1279 {
1280 	return call_int_hook(bprm_creds_from_file, bprm, file);
1281 }
1282 
1283 /**
1284  * security_bprm_check() - Mediate binary handler search
1285  * @bprm: binary program information
1286  *
1287  * This hook mediates the point when a search for a binary handler will begin.
1288  * It allows a check against the @bprm->cred->security value which was set in
1289  * the preceding creds_for_exec call.  The argv list and envp list are reliably
1290  * available in @bprm.  This hook may be called multiple times during a single
1291  * execve.  @bprm contains the linux_binprm structure.
1292  *
1293  * Return: Returns 0 if the hook is successful and permission is granted.
1294  */
security_bprm_check(struct linux_binprm * bprm)1295 int security_bprm_check(struct linux_binprm *bprm)
1296 {
1297 	return call_int_hook(bprm_check_security, bprm);
1298 }
1299 
1300 /**
1301  * security_bprm_committing_creds() - Install creds for a process during exec()
1302  * @bprm: binary program information
1303  *
1304  * Prepare to install the new security attributes of a process being
1305  * transformed by an execve operation, based on the old credentials pointed to
1306  * by @current->cred and the information set in @bprm->cred by the
1307  * bprm_creds_for_exec hook.  @bprm points to the linux_binprm structure.  This
1308  * hook is a good place to perform state changes on the process such as closing
1309  * open file descriptors to which access will no longer be granted when the
1310  * attributes are changed.  This is called immediately before commit_creds().
1311  */
security_bprm_committing_creds(const struct linux_binprm * bprm)1312 void security_bprm_committing_creds(const struct linux_binprm *bprm)
1313 {
1314 	call_void_hook(bprm_committing_creds, bprm);
1315 }
1316 
1317 /**
1318  * security_bprm_committed_creds() - Tidy up after cred install during exec()
1319  * @bprm: binary program information
1320  *
1321  * Tidy up after the installation of the new security attributes of a process
1322  * being transformed by an execve operation.  The new credentials have, by this
1323  * point, been set to @current->cred.  @bprm points to the linux_binprm
1324  * structure.  This hook is a good place to perform state changes on the
1325  * process such as clearing out non-inheritable signal state.  This is called
1326  * immediately after commit_creds().
1327  */
security_bprm_committed_creds(const struct linux_binprm * bprm)1328 void security_bprm_committed_creds(const struct linux_binprm *bprm)
1329 {
1330 	call_void_hook(bprm_committed_creds, bprm);
1331 }
1332 
1333 /**
1334  * security_fs_context_submount() - Initialise fc->security
1335  * @fc: new filesystem context
1336  * @reference: dentry reference for submount/remount
1337  *
1338  * Fill out the ->security field for a new fs_context.
1339  *
1340  * Return: Returns 0 on success or negative error code on failure.
1341  */
security_fs_context_submount(struct fs_context * fc,struct super_block * reference)1342 int security_fs_context_submount(struct fs_context *fc, struct super_block *reference)
1343 {
1344 	return call_int_hook(fs_context_submount, fc, reference);
1345 }
1346 
1347 /**
1348  * security_fs_context_dup() - Duplicate a fs_context LSM blob
1349  * @fc: destination filesystem context
1350  * @src_fc: source filesystem context
1351  *
1352  * Allocate and attach a security structure to sc->security.  This pointer is
1353  * initialised to NULL by the caller.  @fc indicates the new filesystem context.
1354  * @src_fc indicates the original filesystem context.
1355  *
1356  * Return: Returns 0 on success or a negative error code on failure.
1357  */
security_fs_context_dup(struct fs_context * fc,struct fs_context * src_fc)1358 int security_fs_context_dup(struct fs_context *fc, struct fs_context *src_fc)
1359 {
1360 	return call_int_hook(fs_context_dup, fc, src_fc);
1361 }
1362 
1363 /**
1364  * security_fs_context_parse_param() - Configure a filesystem context
1365  * @fc: filesystem context
1366  * @param: filesystem parameter
1367  *
1368  * Userspace provided a parameter to configure a superblock.  The LSM can
1369  * consume the parameter or return it to the caller for use elsewhere.
1370  *
1371  * Return: If the parameter is used by the LSM it should return 0, if it is
1372  *         returned to the caller -ENOPARAM is returned, otherwise a negative
1373  *         error code is returned.
1374  */
security_fs_context_parse_param(struct fs_context * fc,struct fs_parameter * param)1375 int security_fs_context_parse_param(struct fs_context *fc,
1376 				    struct fs_parameter *param)
1377 {
1378 	struct lsm_static_call *scall;
1379 	int trc;
1380 	int rc = -ENOPARAM;
1381 
1382 	lsm_for_each_hook(scall, fs_context_parse_param) {
1383 		trc = scall->hl->hook.fs_context_parse_param(fc, param);
1384 		if (trc == 0)
1385 			rc = 0;
1386 		else if (trc != -ENOPARAM)
1387 			return trc;
1388 	}
1389 	return rc;
1390 }
1391 
1392 /**
1393  * security_sb_alloc() - Allocate a super_block LSM blob
1394  * @sb: filesystem superblock
1395  *
1396  * Allocate and attach a security structure to the sb->s_security field.  The
1397  * s_security field is initialized to NULL when the structure is allocated.
1398  * @sb contains the super_block structure to be modified.
1399  *
1400  * Return: Returns 0 if operation was successful.
1401  */
security_sb_alloc(struct super_block * sb)1402 int security_sb_alloc(struct super_block *sb)
1403 {
1404 	int rc = lsm_superblock_alloc(sb);
1405 
1406 	if (unlikely(rc))
1407 		return rc;
1408 	rc = call_int_hook(sb_alloc_security, sb);
1409 	if (unlikely(rc))
1410 		security_sb_free(sb);
1411 	return rc;
1412 }
1413 
1414 /**
1415  * security_sb_delete() - Release super_block LSM associated objects
1416  * @sb: filesystem superblock
1417  *
1418  * Release objects tied to a superblock (e.g. inodes).  @sb contains the
1419  * super_block structure being released.
1420  */
security_sb_delete(struct super_block * sb)1421 void security_sb_delete(struct super_block *sb)
1422 {
1423 	call_void_hook(sb_delete, sb);
1424 }
1425 
1426 /**
1427  * security_sb_free() - Free a super_block LSM blob
1428  * @sb: filesystem superblock
1429  *
1430  * Deallocate and clear the sb->s_security field.  @sb contains the super_block
1431  * structure to be modified.
1432  */
security_sb_free(struct super_block * sb)1433 void security_sb_free(struct super_block *sb)
1434 {
1435 	call_void_hook(sb_free_security, sb);
1436 	kfree(sb->s_security);
1437 	sb->s_security = NULL;
1438 }
1439 
1440 /**
1441  * security_free_mnt_opts() - Free memory associated with mount options
1442  * @mnt_opts: LSM processed mount options
1443  *
1444  * Free memory associated with @mnt_ops.
1445  */
security_free_mnt_opts(void ** mnt_opts)1446 void security_free_mnt_opts(void **mnt_opts)
1447 {
1448 	if (!*mnt_opts)
1449 		return;
1450 	call_void_hook(sb_free_mnt_opts, *mnt_opts);
1451 	*mnt_opts = NULL;
1452 }
1453 EXPORT_SYMBOL(security_free_mnt_opts);
1454 
1455 /**
1456  * security_sb_eat_lsm_opts() - Consume LSM mount options
1457  * @options: mount options
1458  * @mnt_opts: LSM processed mount options
1459  *
1460  * Eat (scan @options) and save them in @mnt_opts.
1461  *
1462  * Return: Returns 0 on success, negative values on failure.
1463  */
security_sb_eat_lsm_opts(char * options,void ** mnt_opts)1464 int security_sb_eat_lsm_opts(char *options, void **mnt_opts)
1465 {
1466 	return call_int_hook(sb_eat_lsm_opts, options, mnt_opts);
1467 }
1468 EXPORT_SYMBOL(security_sb_eat_lsm_opts);
1469 
1470 /**
1471  * security_sb_mnt_opts_compat() - Check if new mount options are allowed
1472  * @sb: filesystem superblock
1473  * @mnt_opts: new mount options
1474  *
1475  * Determine if the new mount options in @mnt_opts are allowed given the
1476  * existing mounted filesystem at @sb.  @sb superblock being compared.
1477  *
1478  * Return: Returns 0 if options are compatible.
1479  */
security_sb_mnt_opts_compat(struct super_block * sb,void * mnt_opts)1480 int security_sb_mnt_opts_compat(struct super_block *sb,
1481 				void *mnt_opts)
1482 {
1483 	return call_int_hook(sb_mnt_opts_compat, sb, mnt_opts);
1484 }
1485 EXPORT_SYMBOL(security_sb_mnt_opts_compat);
1486 
1487 /**
1488  * security_sb_remount() - Verify no incompatible mount changes during remount
1489  * @sb: filesystem superblock
1490  * @mnt_opts: (re)mount options
1491  *
1492  * Extracts security system specific mount options and verifies no changes are
1493  * being made to those options.
1494  *
1495  * Return: Returns 0 if permission is granted.
1496  */
security_sb_remount(struct super_block * sb,void * mnt_opts)1497 int security_sb_remount(struct super_block *sb,
1498 			void *mnt_opts)
1499 {
1500 	return call_int_hook(sb_remount, sb, mnt_opts);
1501 }
1502 EXPORT_SYMBOL(security_sb_remount);
1503 
1504 /**
1505  * security_sb_kern_mount() - Check if a kernel mount is allowed
1506  * @sb: filesystem superblock
1507  *
1508  * Mount this @sb if allowed by permissions.
1509  *
1510  * Return: Returns 0 if permission is granted.
1511  */
security_sb_kern_mount(const struct super_block * sb)1512 int security_sb_kern_mount(const struct super_block *sb)
1513 {
1514 	return call_int_hook(sb_kern_mount, sb);
1515 }
1516 
1517 /**
1518  * security_sb_show_options() - Output the mount options for a superblock
1519  * @m: output file
1520  * @sb: filesystem superblock
1521  *
1522  * Show (print on @m) mount options for this @sb.
1523  *
1524  * Return: Returns 0 on success, negative values on failure.
1525  */
security_sb_show_options(struct seq_file * m,struct super_block * sb)1526 int security_sb_show_options(struct seq_file *m, struct super_block *sb)
1527 {
1528 	return call_int_hook(sb_show_options, m, sb);
1529 }
1530 
1531 /**
1532  * security_sb_statfs() - Check if accessing fs stats is allowed
1533  * @dentry: superblock handle
1534  *
1535  * Check permission before obtaining filesystem statistics for the @mnt
1536  * mountpoint.  @dentry is a handle on the superblock for the filesystem.
1537  *
1538  * Return: Returns 0 if permission is granted.
1539  */
security_sb_statfs(struct dentry * dentry)1540 int security_sb_statfs(struct dentry *dentry)
1541 {
1542 	return call_int_hook(sb_statfs, dentry);
1543 }
1544 
1545 /**
1546  * security_sb_mount() - Check permission for mounting a filesystem
1547  * @dev_name: filesystem backing device
1548  * @path: mount point
1549  * @type: filesystem type
1550  * @flags: mount flags
1551  * @data: filesystem specific data
1552  *
1553  * Check permission before an object specified by @dev_name is mounted on the
1554  * mount point named by @nd.  For an ordinary mount, @dev_name identifies a
1555  * device if the file system type requires a device.  For a remount
1556  * (@flags & MS_REMOUNT), @dev_name is irrelevant.  For a loopback/bind mount
1557  * (@flags & MS_BIND), @dev_name identifies the	pathname of the object being
1558  * mounted.
1559  *
1560  * Return: Returns 0 if permission is granted.
1561  */
security_sb_mount(const char * dev_name,const struct path * path,const char * type,unsigned long flags,void * data)1562 int security_sb_mount(const char *dev_name, const struct path *path,
1563 		      const char *type, unsigned long flags, void *data)
1564 {
1565 	return call_int_hook(sb_mount, dev_name, path, type, flags, data);
1566 }
1567 
1568 /**
1569  * security_sb_umount() - Check permission for unmounting a filesystem
1570  * @mnt: mounted filesystem
1571  * @flags: unmount flags
1572  *
1573  * Check permission before the @mnt file system is unmounted.
1574  *
1575  * Return: Returns 0 if permission is granted.
1576  */
security_sb_umount(struct vfsmount * mnt,int flags)1577 int security_sb_umount(struct vfsmount *mnt, int flags)
1578 {
1579 	return call_int_hook(sb_umount, mnt, flags);
1580 }
1581 
1582 /**
1583  * security_sb_pivotroot() - Check permissions for pivoting the rootfs
1584  * @old_path: new location for current rootfs
1585  * @new_path: location of the new rootfs
1586  *
1587  * Check permission before pivoting the root filesystem.
1588  *
1589  * Return: Returns 0 if permission is granted.
1590  */
security_sb_pivotroot(const struct path * old_path,const struct path * new_path)1591 int security_sb_pivotroot(const struct path *old_path,
1592 			  const struct path *new_path)
1593 {
1594 	return call_int_hook(sb_pivotroot, old_path, new_path);
1595 }
1596 
1597 /**
1598  * security_sb_set_mnt_opts() - Set the mount options for a filesystem
1599  * @sb: filesystem superblock
1600  * @mnt_opts: binary mount options
1601  * @kern_flags: kernel flags (in)
1602  * @set_kern_flags: kernel flags (out)
1603  *
1604  * Set the security relevant mount options used for a superblock.
1605  *
1606  * Return: Returns 0 on success, error on failure.
1607  */
security_sb_set_mnt_opts(struct super_block * sb,void * mnt_opts,unsigned long kern_flags,unsigned long * set_kern_flags)1608 int security_sb_set_mnt_opts(struct super_block *sb,
1609 			     void *mnt_opts,
1610 			     unsigned long kern_flags,
1611 			     unsigned long *set_kern_flags)
1612 {
1613 	struct lsm_static_call *scall;
1614 	int rc = mnt_opts ? -EOPNOTSUPP : LSM_RET_DEFAULT(sb_set_mnt_opts);
1615 
1616 	lsm_for_each_hook(scall, sb_set_mnt_opts) {
1617 		rc = scall->hl->hook.sb_set_mnt_opts(sb, mnt_opts, kern_flags,
1618 					      set_kern_flags);
1619 		if (rc != LSM_RET_DEFAULT(sb_set_mnt_opts))
1620 			break;
1621 	}
1622 	return rc;
1623 }
1624 EXPORT_SYMBOL(security_sb_set_mnt_opts);
1625 
1626 /**
1627  * security_sb_clone_mnt_opts() - Duplicate superblock mount options
1628  * @oldsb: source superblock
1629  * @newsb: destination superblock
1630  * @kern_flags: kernel flags (in)
1631  * @set_kern_flags: kernel flags (out)
1632  *
1633  * Copy all security options from a given superblock to another.
1634  *
1635  * Return: Returns 0 on success, error on failure.
1636  */
security_sb_clone_mnt_opts(const struct super_block * oldsb,struct super_block * newsb,unsigned long kern_flags,unsigned long * set_kern_flags)1637 int security_sb_clone_mnt_opts(const struct super_block *oldsb,
1638 			       struct super_block *newsb,
1639 			       unsigned long kern_flags,
1640 			       unsigned long *set_kern_flags)
1641 {
1642 	return call_int_hook(sb_clone_mnt_opts, oldsb, newsb,
1643 			     kern_flags, set_kern_flags);
1644 }
1645 EXPORT_SYMBOL(security_sb_clone_mnt_opts);
1646 
1647 /**
1648  * security_move_mount() - Check permissions for moving a mount
1649  * @from_path: source mount point
1650  * @to_path: destination mount point
1651  *
1652  * Check permission before a mount is moved.
1653  *
1654  * Return: Returns 0 if permission is granted.
1655  */
security_move_mount(const struct path * from_path,const struct path * to_path)1656 int security_move_mount(const struct path *from_path,
1657 			const struct path *to_path)
1658 {
1659 	return call_int_hook(move_mount, from_path, to_path);
1660 }
1661 
1662 /**
1663  * security_path_notify() - Check if setting a watch is allowed
1664  * @path: file path
1665  * @mask: event mask
1666  * @obj_type: file path type
1667  *
1668  * Check permissions before setting a watch on events as defined by @mask, on
1669  * an object at @path, whose type is defined by @obj_type.
1670  *
1671  * Return: Returns 0 if permission is granted.
1672  */
security_path_notify(const struct path * path,u64 mask,unsigned int obj_type)1673 int security_path_notify(const struct path *path, u64 mask,
1674 			 unsigned int obj_type)
1675 {
1676 	return call_int_hook(path_notify, path, mask, obj_type);
1677 }
1678 
1679 /**
1680  * security_inode_alloc() - Allocate an inode LSM blob
1681  * @inode: the inode
1682  * @gfp: allocation flags
1683  *
1684  * Allocate and attach a security structure to @inode->i_security.  The
1685  * i_security field is initialized to NULL when the inode structure is
1686  * allocated.
1687  *
1688  * Return: Return 0 if operation was successful.
1689  */
security_inode_alloc(struct inode * inode,gfp_t gfp)1690 int security_inode_alloc(struct inode *inode, gfp_t gfp)
1691 {
1692 	int rc = lsm_inode_alloc(inode, gfp);
1693 
1694 	if (unlikely(rc))
1695 		return rc;
1696 	rc = call_int_hook(inode_alloc_security, inode);
1697 	if (unlikely(rc))
1698 		security_inode_free(inode);
1699 	return rc;
1700 }
1701 
inode_free_by_rcu(struct rcu_head * head)1702 static void inode_free_by_rcu(struct rcu_head *head)
1703 {
1704 	/* The rcu head is at the start of the inode blob */
1705 	call_void_hook(inode_free_security_rcu, head);
1706 	kmem_cache_free(lsm_inode_cache, head);
1707 }
1708 
1709 /**
1710  * security_inode_free() - Free an inode's LSM blob
1711  * @inode: the inode
1712  *
1713  * Release any LSM resources associated with @inode, although due to the
1714  * inode's RCU protections it is possible that the resources will not be
1715  * fully released until after the current RCU grace period has elapsed.
1716  *
1717  * It is important for LSMs to note that despite being present in a call to
1718  * security_inode_free(), @inode may still be referenced in a VFS path walk
1719  * and calls to security_inode_permission() may be made during, or after,
1720  * a call to security_inode_free().  For this reason the inode->i_security
1721  * field is released via a call_rcu() callback and any LSMs which need to
1722  * retain inode state for use in security_inode_permission() should only
1723  * release that state in the inode_free_security_rcu() LSM hook callback.
1724  */
security_inode_free(struct inode * inode)1725 void security_inode_free(struct inode *inode)
1726 {
1727 	call_void_hook(inode_free_security, inode);
1728 	if (!inode->i_security)
1729 		return;
1730 	call_rcu((struct rcu_head *)inode->i_security, inode_free_by_rcu);
1731 }
1732 
1733 /**
1734  * security_dentry_init_security() - Perform dentry initialization
1735  * @dentry: the dentry to initialize
1736  * @mode: mode used to determine resource type
1737  * @name: name of the last path component
1738  * @xattr_name: name of the security/LSM xattr
1739  * @ctx: pointer to the resulting LSM context
1740  * @ctxlen: length of @ctx
1741  *
1742  * Compute a context for a dentry as the inode is not yet available since NFSv4
1743  * has no label backed by an EA anyway.  It is important to note that
1744  * @xattr_name does not need to be free'd by the caller, it is a static string.
1745  *
1746  * Return: Returns 0 on success, negative values on failure.
1747  */
security_dentry_init_security(struct dentry * dentry,int mode,const struct qstr * name,const char ** xattr_name,void ** ctx,u32 * ctxlen)1748 int security_dentry_init_security(struct dentry *dentry, int mode,
1749 				  const struct qstr *name,
1750 				  const char **xattr_name, void **ctx,
1751 				  u32 *ctxlen)
1752 {
1753 	return call_int_hook(dentry_init_security, dentry, mode, name,
1754 			     xattr_name, ctx, ctxlen);
1755 }
1756 EXPORT_SYMBOL(security_dentry_init_security);
1757 
1758 /**
1759  * security_dentry_create_files_as() - Perform dentry initialization
1760  * @dentry: the dentry to initialize
1761  * @mode: mode used to determine resource type
1762  * @name: name of the last path component
1763  * @old: creds to use for LSM context calculations
1764  * @new: creds to modify
1765  *
1766  * Compute a context for a dentry as the inode is not yet available and set
1767  * that context in passed in creds so that new files are created using that
1768  * context. Context is calculated using the passed in creds and not the creds
1769  * of the caller.
1770  *
1771  * Return: Returns 0 on success, error on failure.
1772  */
security_dentry_create_files_as(struct dentry * dentry,int mode,struct qstr * name,const struct cred * old,struct cred * new)1773 int security_dentry_create_files_as(struct dentry *dentry, int mode,
1774 				    struct qstr *name,
1775 				    const struct cred *old, struct cred *new)
1776 {
1777 	return call_int_hook(dentry_create_files_as, dentry, mode,
1778 			     name, old, new);
1779 }
1780 EXPORT_SYMBOL(security_dentry_create_files_as);
1781 
1782 /**
1783  * security_inode_init_security() - Initialize an inode's LSM context
1784  * @inode: the inode
1785  * @dir: parent directory
1786  * @qstr: last component of the pathname
1787  * @initxattrs: callback function to write xattrs
1788  * @fs_data: filesystem specific data
1789  *
1790  * Obtain the security attribute name suffix and value to set on a newly
1791  * created inode and set up the incore security field for the new inode.  This
1792  * hook is called by the fs code as part of the inode creation transaction and
1793  * provides for atomic labeling of the inode, unlike the post_create/mkdir/...
1794  * hooks called by the VFS.
1795  *
1796  * The hook function is expected to populate the xattrs array, by calling
1797  * lsm_get_xattr_slot() to retrieve the slots reserved by the security module
1798  * with the lbs_xattr_count field of the lsm_blob_sizes structure.  For each
1799  * slot, the hook function should set ->name to the attribute name suffix
1800  * (e.g. selinux), to allocate ->value (will be freed by the caller) and set it
1801  * to the attribute value, to set ->value_len to the length of the value.  If
1802  * the security module does not use security attributes or does not wish to put
1803  * a security attribute on this particular inode, then it should return
1804  * -EOPNOTSUPP to skip this processing.
1805  *
1806  * Return: Returns 0 if the LSM successfully initialized all of the inode
1807  *         security attributes that are required, negative values otherwise.
1808  */
security_inode_init_security(struct inode * inode,struct inode * dir,const struct qstr * qstr,const initxattrs initxattrs,void * fs_data)1809 int security_inode_init_security(struct inode *inode, struct inode *dir,
1810 				 const struct qstr *qstr,
1811 				 const initxattrs initxattrs, void *fs_data)
1812 {
1813 	struct lsm_static_call *scall;
1814 	struct xattr *new_xattrs = NULL;
1815 	int ret = -EOPNOTSUPP, xattr_count = 0;
1816 
1817 	if (unlikely(IS_PRIVATE(inode)))
1818 		return 0;
1819 
1820 	if (!blob_sizes.lbs_xattr_count)
1821 		return 0;
1822 
1823 	if (initxattrs) {
1824 		/* Allocate +1 as terminator. */
1825 		new_xattrs = kcalloc(blob_sizes.lbs_xattr_count + 1,
1826 				     sizeof(*new_xattrs), GFP_NOFS);
1827 		if (!new_xattrs)
1828 			return -ENOMEM;
1829 	}
1830 
1831 	lsm_for_each_hook(scall, inode_init_security) {
1832 		ret = scall->hl->hook.inode_init_security(inode, dir, qstr, new_xattrs,
1833 						  &xattr_count);
1834 		if (ret && ret != -EOPNOTSUPP)
1835 			goto out;
1836 		/*
1837 		 * As documented in lsm_hooks.h, -EOPNOTSUPP in this context
1838 		 * means that the LSM is not willing to provide an xattr, not
1839 		 * that it wants to signal an error. Thus, continue to invoke
1840 		 * the remaining LSMs.
1841 		 */
1842 	}
1843 
1844 	/* If initxattrs() is NULL, xattr_count is zero, skip the call. */
1845 	if (!xattr_count)
1846 		goto out;
1847 
1848 	ret = initxattrs(inode, new_xattrs, fs_data);
1849 out:
1850 	for (; xattr_count > 0; xattr_count--)
1851 		kfree(new_xattrs[xattr_count - 1].value);
1852 	kfree(new_xattrs);
1853 	return (ret == -EOPNOTSUPP) ? 0 : ret;
1854 }
1855 EXPORT_SYMBOL(security_inode_init_security);
1856 
1857 /**
1858  * security_inode_init_security_anon() - Initialize an anonymous inode
1859  * @inode: the inode
1860  * @name: the anonymous inode class
1861  * @context_inode: an optional related inode
1862  *
1863  * Set up the incore security field for the new anonymous inode and return
1864  * whether the inode creation is permitted by the security module or not.
1865  *
1866  * Return: Returns 0 on success, -EACCES if the security module denies the
1867  * creation of this inode, or another -errno upon other errors.
1868  */
security_inode_init_security_anon(struct inode * inode,const struct qstr * name,const struct inode * context_inode)1869 int security_inode_init_security_anon(struct inode *inode,
1870 				      const struct qstr *name,
1871 				      const struct inode *context_inode)
1872 {
1873 	return call_int_hook(inode_init_security_anon, inode, name,
1874 			     context_inode);
1875 }
1876 
1877 #ifdef CONFIG_SECURITY_PATH
1878 /**
1879  * security_path_mknod() - Check if creating a special file is allowed
1880  * @dir: parent directory
1881  * @dentry: new file
1882  * @mode: new file mode
1883  * @dev: device number
1884  *
1885  * Check permissions when creating a file. Note that this hook is called even
1886  * if mknod operation is being done for a regular file.
1887  *
1888  * Return: Returns 0 if permission is granted.
1889  */
security_path_mknod(const struct path * dir,struct dentry * dentry,umode_t mode,unsigned int dev)1890 int security_path_mknod(const struct path *dir, struct dentry *dentry,
1891 			umode_t mode, unsigned int dev)
1892 {
1893 	if (unlikely(IS_PRIVATE(d_backing_inode(dir->dentry))))
1894 		return 0;
1895 	return call_int_hook(path_mknod, dir, dentry, mode, dev);
1896 }
1897 EXPORT_SYMBOL(security_path_mknod);
1898 
1899 /**
1900  * security_path_post_mknod() - Update inode security after reg file creation
1901  * @idmap: idmap of the mount
1902  * @dentry: new file
1903  *
1904  * Update inode security field after a regular file has been created.
1905  */
security_path_post_mknod(struct mnt_idmap * idmap,struct dentry * dentry)1906 void security_path_post_mknod(struct mnt_idmap *idmap, struct dentry *dentry)
1907 {
1908 	if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
1909 		return;
1910 	call_void_hook(path_post_mknod, idmap, dentry);
1911 }
1912 
1913 /**
1914  * security_path_mkdir() - Check if creating a new directory is allowed
1915  * @dir: parent directory
1916  * @dentry: new directory
1917  * @mode: new directory mode
1918  *
1919  * Check permissions to create a new directory in the existing directory.
1920  *
1921  * Return: Returns 0 if permission is granted.
1922  */
security_path_mkdir(const struct path * dir,struct dentry * dentry,umode_t mode)1923 int security_path_mkdir(const struct path *dir, struct dentry *dentry,
1924 			umode_t mode)
1925 {
1926 	if (unlikely(IS_PRIVATE(d_backing_inode(dir->dentry))))
1927 		return 0;
1928 	return call_int_hook(path_mkdir, dir, dentry, mode);
1929 }
1930 EXPORT_SYMBOL(security_path_mkdir);
1931 
1932 /**
1933  * security_path_rmdir() - Check if removing a directory is allowed
1934  * @dir: parent directory
1935  * @dentry: directory to remove
1936  *
1937  * Check the permission to remove a directory.
1938  *
1939  * Return: Returns 0 if permission is granted.
1940  */
security_path_rmdir(const struct path * dir,struct dentry * dentry)1941 int security_path_rmdir(const struct path *dir, struct dentry *dentry)
1942 {
1943 	if (unlikely(IS_PRIVATE(d_backing_inode(dir->dentry))))
1944 		return 0;
1945 	return call_int_hook(path_rmdir, dir, dentry);
1946 }
1947 
1948 /**
1949  * security_path_unlink() - Check if removing a hard link is allowed
1950  * @dir: parent directory
1951  * @dentry: file
1952  *
1953  * Check the permission to remove a hard link to a file.
1954  *
1955  * Return: Returns 0 if permission is granted.
1956  */
security_path_unlink(const struct path * dir,struct dentry * dentry)1957 int security_path_unlink(const struct path *dir, struct dentry *dentry)
1958 {
1959 	if (unlikely(IS_PRIVATE(d_backing_inode(dir->dentry))))
1960 		return 0;
1961 	return call_int_hook(path_unlink, dir, dentry);
1962 }
1963 EXPORT_SYMBOL(security_path_unlink);
1964 
1965 /**
1966  * security_path_symlink() - Check if creating a symbolic link is allowed
1967  * @dir: parent directory
1968  * @dentry: symbolic link
1969  * @old_name: file pathname
1970  *
1971  * Check the permission to create a symbolic link to a file.
1972  *
1973  * Return: Returns 0 if permission is granted.
1974  */
security_path_symlink(const struct path * dir,struct dentry * dentry,const char * old_name)1975 int security_path_symlink(const struct path *dir, struct dentry *dentry,
1976 			  const char *old_name)
1977 {
1978 	if (unlikely(IS_PRIVATE(d_backing_inode(dir->dentry))))
1979 		return 0;
1980 	return call_int_hook(path_symlink, dir, dentry, old_name);
1981 }
1982 
1983 /**
1984  * security_path_link - Check if creating a hard link is allowed
1985  * @old_dentry: existing file
1986  * @new_dir: new parent directory
1987  * @new_dentry: new link
1988  *
1989  * Check permission before creating a new hard link to a file.
1990  *
1991  * Return: Returns 0 if permission is granted.
1992  */
security_path_link(struct dentry * old_dentry,const struct path * new_dir,struct dentry * new_dentry)1993 int security_path_link(struct dentry *old_dentry, const struct path *new_dir,
1994 		       struct dentry *new_dentry)
1995 {
1996 	if (unlikely(IS_PRIVATE(d_backing_inode(old_dentry))))
1997 		return 0;
1998 	return call_int_hook(path_link, old_dentry, new_dir, new_dentry);
1999 }
2000 
2001 /**
2002  * security_path_rename() - Check if renaming a file is allowed
2003  * @old_dir: parent directory of the old file
2004  * @old_dentry: the old file
2005  * @new_dir: parent directory of the new file
2006  * @new_dentry: the new file
2007  * @flags: flags
2008  *
2009  * Check for permission to rename a file or directory.
2010  *
2011  * Return: Returns 0 if permission is granted.
2012  */
security_path_rename(const struct path * old_dir,struct dentry * old_dentry,const struct path * new_dir,struct dentry * new_dentry,unsigned int flags)2013 int security_path_rename(const struct path *old_dir, struct dentry *old_dentry,
2014 			 const struct path *new_dir, struct dentry *new_dentry,
2015 			 unsigned int flags)
2016 {
2017 	if (unlikely(IS_PRIVATE(d_backing_inode(old_dentry)) ||
2018 		     (d_is_positive(new_dentry) &&
2019 		      IS_PRIVATE(d_backing_inode(new_dentry)))))
2020 		return 0;
2021 
2022 	return call_int_hook(path_rename, old_dir, old_dentry, new_dir,
2023 			     new_dentry, flags);
2024 }
2025 EXPORT_SYMBOL(security_path_rename);
2026 
2027 /**
2028  * security_path_truncate() - Check if truncating a file is allowed
2029  * @path: file
2030  *
2031  * Check permission before truncating the file indicated by path.  Note that
2032  * truncation permissions may also be checked based on already opened files,
2033  * using the security_file_truncate() hook.
2034  *
2035  * Return: Returns 0 if permission is granted.
2036  */
security_path_truncate(const struct path * path)2037 int security_path_truncate(const struct path *path)
2038 {
2039 	if (unlikely(IS_PRIVATE(d_backing_inode(path->dentry))))
2040 		return 0;
2041 	return call_int_hook(path_truncate, path);
2042 }
2043 
2044 /**
2045  * security_path_chmod() - Check if changing the file's mode is allowed
2046  * @path: file
2047  * @mode: new mode
2048  *
2049  * Check for permission to change a mode of the file @path. The new mode is
2050  * specified in @mode which is a bitmask of constants from
2051  * <include/uapi/linux/stat.h>.
2052  *
2053  * Return: Returns 0 if permission is granted.
2054  */
security_path_chmod(const struct path * path,umode_t mode)2055 int security_path_chmod(const struct path *path, umode_t mode)
2056 {
2057 	if (unlikely(IS_PRIVATE(d_backing_inode(path->dentry))))
2058 		return 0;
2059 	return call_int_hook(path_chmod, path, mode);
2060 }
2061 
2062 /**
2063  * security_path_chown() - Check if changing the file's owner/group is allowed
2064  * @path: file
2065  * @uid: file owner
2066  * @gid: file group
2067  *
2068  * Check for permission to change owner/group of a file or directory.
2069  *
2070  * Return: Returns 0 if permission is granted.
2071  */
security_path_chown(const struct path * path,kuid_t uid,kgid_t gid)2072 int security_path_chown(const struct path *path, kuid_t uid, kgid_t gid)
2073 {
2074 	if (unlikely(IS_PRIVATE(d_backing_inode(path->dentry))))
2075 		return 0;
2076 	return call_int_hook(path_chown, path, uid, gid);
2077 }
2078 
2079 /**
2080  * security_path_chroot() - Check if changing the root directory is allowed
2081  * @path: directory
2082  *
2083  * Check for permission to change root directory.
2084  *
2085  * Return: Returns 0 if permission is granted.
2086  */
security_path_chroot(const struct path * path)2087 int security_path_chroot(const struct path *path)
2088 {
2089 	return call_int_hook(path_chroot, path);
2090 }
2091 #endif /* CONFIG_SECURITY_PATH */
2092 
2093 /**
2094  * security_inode_create() - Check if creating a file is allowed
2095  * @dir: the parent directory
2096  * @dentry: the file being created
2097  * @mode: requested file mode
2098  *
2099  * Check permission to create a regular file.
2100  *
2101  * Return: Returns 0 if permission is granted.
2102  */
security_inode_create(struct inode * dir,struct dentry * dentry,umode_t mode)2103 int security_inode_create(struct inode *dir, struct dentry *dentry,
2104 			  umode_t mode)
2105 {
2106 	if (unlikely(IS_PRIVATE(dir)))
2107 		return 0;
2108 	return call_int_hook(inode_create, dir, dentry, mode);
2109 }
2110 EXPORT_SYMBOL_GPL(security_inode_create);
2111 
2112 /**
2113  * security_inode_post_create_tmpfile() - Update inode security of new tmpfile
2114  * @idmap: idmap of the mount
2115  * @inode: inode of the new tmpfile
2116  *
2117  * Update inode security data after a tmpfile has been created.
2118  */
security_inode_post_create_tmpfile(struct mnt_idmap * idmap,struct inode * inode)2119 void security_inode_post_create_tmpfile(struct mnt_idmap *idmap,
2120 					struct inode *inode)
2121 {
2122 	if (unlikely(IS_PRIVATE(inode)))
2123 		return;
2124 	call_void_hook(inode_post_create_tmpfile, idmap, inode);
2125 }
2126 
2127 /**
2128  * security_inode_link() - Check if creating a hard link is allowed
2129  * @old_dentry: existing file
2130  * @dir: new parent directory
2131  * @new_dentry: new link
2132  *
2133  * Check permission before creating a new hard link to a file.
2134  *
2135  * Return: Returns 0 if permission is granted.
2136  */
security_inode_link(struct dentry * old_dentry,struct inode * dir,struct dentry * new_dentry)2137 int security_inode_link(struct dentry *old_dentry, struct inode *dir,
2138 			struct dentry *new_dentry)
2139 {
2140 	if (unlikely(IS_PRIVATE(d_backing_inode(old_dentry))))
2141 		return 0;
2142 	return call_int_hook(inode_link, old_dentry, dir, new_dentry);
2143 }
2144 
2145 /**
2146  * security_inode_unlink() - Check if removing a hard link is allowed
2147  * @dir: parent directory
2148  * @dentry: file
2149  *
2150  * Check the permission to remove a hard link to a file.
2151  *
2152  * Return: Returns 0 if permission is granted.
2153  */
security_inode_unlink(struct inode * dir,struct dentry * dentry)2154 int security_inode_unlink(struct inode *dir, struct dentry *dentry)
2155 {
2156 	if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
2157 		return 0;
2158 	return call_int_hook(inode_unlink, dir, dentry);
2159 }
2160 
2161 /**
2162  * security_inode_symlink() - Check if creating a symbolic link is allowed
2163  * @dir: parent directory
2164  * @dentry: symbolic link
2165  * @old_name: existing filename
2166  *
2167  * Check the permission to create a symbolic link to a file.
2168  *
2169  * Return: Returns 0 if permission is granted.
2170  */
security_inode_symlink(struct inode * dir,struct dentry * dentry,const char * old_name)2171 int security_inode_symlink(struct inode *dir, struct dentry *dentry,
2172 			   const char *old_name)
2173 {
2174 	if (unlikely(IS_PRIVATE(dir)))
2175 		return 0;
2176 	return call_int_hook(inode_symlink, dir, dentry, old_name);
2177 }
2178 
2179 /**
2180  * security_inode_mkdir() - Check if creation a new director is allowed
2181  * @dir: parent directory
2182  * @dentry: new directory
2183  * @mode: new directory mode
2184  *
2185  * Check permissions to create a new directory in the existing directory
2186  * associated with inode structure @dir.
2187  *
2188  * Return: Returns 0 if permission is granted.
2189  */
security_inode_mkdir(struct inode * dir,struct dentry * dentry,umode_t mode)2190 int security_inode_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
2191 {
2192 	if (unlikely(IS_PRIVATE(dir)))
2193 		return 0;
2194 	return call_int_hook(inode_mkdir, dir, dentry, mode);
2195 }
2196 EXPORT_SYMBOL_GPL(security_inode_mkdir);
2197 
2198 /**
2199  * security_inode_rmdir() - Check if removing a directory is allowed
2200  * @dir: parent directory
2201  * @dentry: directory to be removed
2202  *
2203  * Check the permission to remove a directory.
2204  *
2205  * Return: Returns 0 if permission is granted.
2206  */
security_inode_rmdir(struct inode * dir,struct dentry * dentry)2207 int security_inode_rmdir(struct inode *dir, struct dentry *dentry)
2208 {
2209 	if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
2210 		return 0;
2211 	return call_int_hook(inode_rmdir, dir, dentry);
2212 }
2213 
2214 /**
2215  * security_inode_mknod() - Check if creating a special file is allowed
2216  * @dir: parent directory
2217  * @dentry: new file
2218  * @mode: new file mode
2219  * @dev: device number
2220  *
2221  * Check permissions when creating a special file (or a socket or a fifo file
2222  * created via the mknod system call).  Note that if mknod operation is being
2223  * done for a regular file, then the create hook will be called and not this
2224  * hook.
2225  *
2226  * Return: Returns 0 if permission is granted.
2227  */
security_inode_mknod(struct inode * dir,struct dentry * dentry,umode_t mode,dev_t dev)2228 int security_inode_mknod(struct inode *dir, struct dentry *dentry,
2229 			 umode_t mode, dev_t dev)
2230 {
2231 	if (unlikely(IS_PRIVATE(dir)))
2232 		return 0;
2233 	return call_int_hook(inode_mknod, dir, dentry, mode, dev);
2234 }
2235 
2236 /**
2237  * security_inode_rename() - Check if renaming a file is allowed
2238  * @old_dir: parent directory of the old file
2239  * @old_dentry: the old file
2240  * @new_dir: parent directory of the new file
2241  * @new_dentry: the new file
2242  * @flags: flags
2243  *
2244  * Check for permission to rename a file or directory.
2245  *
2246  * Return: Returns 0 if permission is granted.
2247  */
security_inode_rename(struct inode * old_dir,struct dentry * old_dentry,struct inode * new_dir,struct dentry * new_dentry,unsigned int flags)2248 int security_inode_rename(struct inode *old_dir, struct dentry *old_dentry,
2249 			  struct inode *new_dir, struct dentry *new_dentry,
2250 			  unsigned int flags)
2251 {
2252 	if (unlikely(IS_PRIVATE(d_backing_inode(old_dentry)) ||
2253 		     (d_is_positive(new_dentry) &&
2254 		      IS_PRIVATE(d_backing_inode(new_dentry)))))
2255 		return 0;
2256 
2257 	if (flags & RENAME_EXCHANGE) {
2258 		int err = call_int_hook(inode_rename, new_dir, new_dentry,
2259 					old_dir, old_dentry);
2260 		if (err)
2261 			return err;
2262 	}
2263 
2264 	return call_int_hook(inode_rename, old_dir, old_dentry,
2265 			     new_dir, new_dentry);
2266 }
2267 
2268 /**
2269  * security_inode_readlink() - Check if reading a symbolic link is allowed
2270  * @dentry: link
2271  *
2272  * Check the permission to read the symbolic link.
2273  *
2274  * Return: Returns 0 if permission is granted.
2275  */
security_inode_readlink(struct dentry * dentry)2276 int security_inode_readlink(struct dentry *dentry)
2277 {
2278 	if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
2279 		return 0;
2280 	return call_int_hook(inode_readlink, dentry);
2281 }
2282 
2283 /**
2284  * security_inode_follow_link() - Check if following a symbolic link is allowed
2285  * @dentry: link dentry
2286  * @inode: link inode
2287  * @rcu: true if in RCU-walk mode
2288  *
2289  * Check permission to follow a symbolic link when looking up a pathname.  If
2290  * @rcu is true, @inode is not stable.
2291  *
2292  * Return: Returns 0 if permission is granted.
2293  */
security_inode_follow_link(struct dentry * dentry,struct inode * inode,bool rcu)2294 int security_inode_follow_link(struct dentry *dentry, struct inode *inode,
2295 			       bool rcu)
2296 {
2297 	if (unlikely(IS_PRIVATE(inode)))
2298 		return 0;
2299 	return call_int_hook(inode_follow_link, dentry, inode, rcu);
2300 }
2301 
2302 /**
2303  * security_inode_permission() - Check if accessing an inode is allowed
2304  * @inode: inode
2305  * @mask: access mask
2306  *
2307  * Check permission before accessing an inode.  This hook is called by the
2308  * existing Linux permission function, so a security module can use it to
2309  * provide additional checking for existing Linux permission checks.  Notice
2310  * that this hook is called when a file is opened (as well as many other
2311  * operations), whereas the file_security_ops permission hook is called when
2312  * the actual read/write operations are performed.
2313  *
2314  * Return: Returns 0 if permission is granted.
2315  */
security_inode_permission(struct inode * inode,int mask)2316 int security_inode_permission(struct inode *inode, int mask)
2317 {
2318 	if (unlikely(IS_PRIVATE(inode)))
2319 		return 0;
2320 	return call_int_hook(inode_permission, inode, mask);
2321 }
2322 
2323 /**
2324  * security_inode_setattr() - Check if setting file attributes is allowed
2325  * @idmap: idmap of the mount
2326  * @dentry: file
2327  * @attr: new attributes
2328  *
2329  * Check permission before setting file attributes.  Note that the kernel call
2330  * to notify_change is performed from several locations, whenever file
2331  * attributes change (such as when a file is truncated, chown/chmod operations,
2332  * transferring disk quotas, etc).
2333  *
2334  * Return: Returns 0 if permission is granted.
2335  */
security_inode_setattr(struct mnt_idmap * idmap,struct dentry * dentry,struct iattr * attr)2336 int security_inode_setattr(struct mnt_idmap *idmap,
2337 			   struct dentry *dentry, struct iattr *attr)
2338 {
2339 	if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
2340 		return 0;
2341 	return call_int_hook(inode_setattr, idmap, dentry, attr);
2342 }
2343 EXPORT_SYMBOL_GPL(security_inode_setattr);
2344 
2345 /**
2346  * security_inode_post_setattr() - Update the inode after a setattr operation
2347  * @idmap: idmap of the mount
2348  * @dentry: file
2349  * @ia_valid: file attributes set
2350  *
2351  * Update inode security field after successful setting file attributes.
2352  */
security_inode_post_setattr(struct mnt_idmap * idmap,struct dentry * dentry,int ia_valid)2353 void security_inode_post_setattr(struct mnt_idmap *idmap, struct dentry *dentry,
2354 				 int ia_valid)
2355 {
2356 	if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
2357 		return;
2358 	call_void_hook(inode_post_setattr, idmap, dentry, ia_valid);
2359 }
2360 
2361 /**
2362  * security_inode_getattr() - Check if getting file attributes is allowed
2363  * @path: file
2364  *
2365  * Check permission before obtaining file attributes.
2366  *
2367  * Return: Returns 0 if permission is granted.
2368  */
security_inode_getattr(const struct path * path)2369 int security_inode_getattr(const struct path *path)
2370 {
2371 	if (unlikely(IS_PRIVATE(d_backing_inode(path->dentry))))
2372 		return 0;
2373 	return call_int_hook(inode_getattr, path);
2374 }
2375 
2376 /**
2377  * security_inode_setxattr() - Check if setting file xattrs is allowed
2378  * @idmap: idmap of the mount
2379  * @dentry: file
2380  * @name: xattr name
2381  * @value: xattr value
2382  * @size: size of xattr value
2383  * @flags: flags
2384  *
2385  * This hook performs the desired permission checks before setting the extended
2386  * attributes (xattrs) on @dentry.  It is important to note that we have some
2387  * additional logic before the main LSM implementation calls to detect if we
2388  * need to perform an additional capability check at the LSM layer.
2389  *
2390  * Normally we enforce a capability check prior to executing the various LSM
2391  * hook implementations, but if a LSM wants to avoid this capability check,
2392  * it can register a 'inode_xattr_skipcap' hook and return a value of 1 for
2393  * xattrs that it wants to avoid the capability check, leaving the LSM fully
2394  * responsible for enforcing the access control for the specific xattr.  If all
2395  * of the enabled LSMs refrain from registering a 'inode_xattr_skipcap' hook,
2396  * or return a 0 (the default return value), the capability check is still
2397  * performed.  If no 'inode_xattr_skipcap' hooks are registered the capability
2398  * check is performed.
2399  *
2400  * Return: Returns 0 if permission is granted.
2401  */
security_inode_setxattr(struct mnt_idmap * idmap,struct dentry * dentry,const char * name,const void * value,size_t size,int flags)2402 int security_inode_setxattr(struct mnt_idmap *idmap,
2403 			    struct dentry *dentry, const char *name,
2404 			    const void *value, size_t size, int flags)
2405 {
2406 	int rc;
2407 
2408 	if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
2409 		return 0;
2410 
2411 	/* enforce the capability checks at the lsm layer, if needed */
2412 	if (!call_int_hook(inode_xattr_skipcap, name)) {
2413 		rc = cap_inode_setxattr(dentry, name, value, size, flags);
2414 		if (rc)
2415 			return rc;
2416 	}
2417 
2418 	return call_int_hook(inode_setxattr, idmap, dentry, name, value, size,
2419 			     flags);
2420 }
2421 
2422 /**
2423  * security_inode_set_acl() - Check if setting posix acls is allowed
2424  * @idmap: idmap of the mount
2425  * @dentry: file
2426  * @acl_name: acl name
2427  * @kacl: acl struct
2428  *
2429  * Check permission before setting posix acls, the posix acls in @kacl are
2430  * identified by @acl_name.
2431  *
2432  * Return: Returns 0 if permission is granted.
2433  */
security_inode_set_acl(struct mnt_idmap * idmap,struct dentry * dentry,const char * acl_name,struct posix_acl * kacl)2434 int security_inode_set_acl(struct mnt_idmap *idmap,
2435 			   struct dentry *dentry, const char *acl_name,
2436 			   struct posix_acl *kacl)
2437 {
2438 	if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
2439 		return 0;
2440 	return call_int_hook(inode_set_acl, idmap, dentry, acl_name, kacl);
2441 }
2442 
2443 /**
2444  * security_inode_post_set_acl() - Update inode security from posix acls set
2445  * @dentry: file
2446  * @acl_name: acl name
2447  * @kacl: acl struct
2448  *
2449  * Update inode security data after successfully setting posix acls on @dentry.
2450  * The posix acls in @kacl are identified by @acl_name.
2451  */
security_inode_post_set_acl(struct dentry * dentry,const char * acl_name,struct posix_acl * kacl)2452 void security_inode_post_set_acl(struct dentry *dentry, const char *acl_name,
2453 				 struct posix_acl *kacl)
2454 {
2455 	if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
2456 		return;
2457 	call_void_hook(inode_post_set_acl, dentry, acl_name, kacl);
2458 }
2459 
2460 /**
2461  * security_inode_get_acl() - Check if reading posix acls is allowed
2462  * @idmap: idmap of the mount
2463  * @dentry: file
2464  * @acl_name: acl name
2465  *
2466  * Check permission before getting osix acls, the posix acls are identified by
2467  * @acl_name.
2468  *
2469  * Return: Returns 0 if permission is granted.
2470  */
security_inode_get_acl(struct mnt_idmap * idmap,struct dentry * dentry,const char * acl_name)2471 int security_inode_get_acl(struct mnt_idmap *idmap,
2472 			   struct dentry *dentry, const char *acl_name)
2473 {
2474 	if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
2475 		return 0;
2476 	return call_int_hook(inode_get_acl, idmap, dentry, acl_name);
2477 }
2478 
2479 /**
2480  * security_inode_remove_acl() - Check if removing a posix acl is allowed
2481  * @idmap: idmap of the mount
2482  * @dentry: file
2483  * @acl_name: acl name
2484  *
2485  * Check permission before removing posix acls, the posix acls are identified
2486  * by @acl_name.
2487  *
2488  * Return: Returns 0 if permission is granted.
2489  */
security_inode_remove_acl(struct mnt_idmap * idmap,struct dentry * dentry,const char * acl_name)2490 int security_inode_remove_acl(struct mnt_idmap *idmap,
2491 			      struct dentry *dentry, const char *acl_name)
2492 {
2493 	if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
2494 		return 0;
2495 	return call_int_hook(inode_remove_acl, idmap, dentry, acl_name);
2496 }
2497 
2498 /**
2499  * security_inode_post_remove_acl() - Update inode security after rm posix acls
2500  * @idmap: idmap of the mount
2501  * @dentry: file
2502  * @acl_name: acl name
2503  *
2504  * Update inode security data after successfully removing posix acls on
2505  * @dentry in @idmap. The posix acls are identified by @acl_name.
2506  */
security_inode_post_remove_acl(struct mnt_idmap * idmap,struct dentry * dentry,const char * acl_name)2507 void security_inode_post_remove_acl(struct mnt_idmap *idmap,
2508 				    struct dentry *dentry, const char *acl_name)
2509 {
2510 	if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
2511 		return;
2512 	call_void_hook(inode_post_remove_acl, idmap, dentry, acl_name);
2513 }
2514 
2515 /**
2516  * security_inode_post_setxattr() - Update the inode after a setxattr operation
2517  * @dentry: file
2518  * @name: xattr name
2519  * @value: xattr value
2520  * @size: xattr value size
2521  * @flags: flags
2522  *
2523  * Update inode security field after successful setxattr operation.
2524  */
security_inode_post_setxattr(struct dentry * dentry,const char * name,const void * value,size_t size,int flags)2525 void security_inode_post_setxattr(struct dentry *dentry, const char *name,
2526 				  const void *value, size_t size, int flags)
2527 {
2528 	if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
2529 		return;
2530 	call_void_hook(inode_post_setxattr, dentry, name, value, size, flags);
2531 }
2532 
2533 /**
2534  * security_inode_getxattr() - Check if xattr access is allowed
2535  * @dentry: file
2536  * @name: xattr name
2537  *
2538  * Check permission before obtaining the extended attributes identified by
2539  * @name for @dentry.
2540  *
2541  * Return: Returns 0 if permission is granted.
2542  */
security_inode_getxattr(struct dentry * dentry,const char * name)2543 int security_inode_getxattr(struct dentry *dentry, const char *name)
2544 {
2545 	if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
2546 		return 0;
2547 	return call_int_hook(inode_getxattr, dentry, name);
2548 }
2549 
2550 /**
2551  * security_inode_listxattr() - Check if listing xattrs is allowed
2552  * @dentry: file
2553  *
2554  * Check permission before obtaining the list of extended attribute names for
2555  * @dentry.
2556  *
2557  * Return: Returns 0 if permission is granted.
2558  */
security_inode_listxattr(struct dentry * dentry)2559 int security_inode_listxattr(struct dentry *dentry)
2560 {
2561 	if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
2562 		return 0;
2563 	return call_int_hook(inode_listxattr, dentry);
2564 }
2565 
2566 /**
2567  * security_inode_removexattr() - Check if removing an xattr is allowed
2568  * @idmap: idmap of the mount
2569  * @dentry: file
2570  * @name: xattr name
2571  *
2572  * This hook performs the desired permission checks before setting the extended
2573  * attributes (xattrs) on @dentry.  It is important to note that we have some
2574  * additional logic before the main LSM implementation calls to detect if we
2575  * need to perform an additional capability check at the LSM layer.
2576  *
2577  * Normally we enforce a capability check prior to executing the various LSM
2578  * hook implementations, but if a LSM wants to avoid this capability check,
2579  * it can register a 'inode_xattr_skipcap' hook and return a value of 1 for
2580  * xattrs that it wants to avoid the capability check, leaving the LSM fully
2581  * responsible for enforcing the access control for the specific xattr.  If all
2582  * of the enabled LSMs refrain from registering a 'inode_xattr_skipcap' hook,
2583  * or return a 0 (the default return value), the capability check is still
2584  * performed.  If no 'inode_xattr_skipcap' hooks are registered the capability
2585  * check is performed.
2586  *
2587  * Return: Returns 0 if permission is granted.
2588  */
security_inode_removexattr(struct mnt_idmap * idmap,struct dentry * dentry,const char * name)2589 int security_inode_removexattr(struct mnt_idmap *idmap,
2590 			       struct dentry *dentry, const char *name)
2591 {
2592 	int rc;
2593 
2594 	if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
2595 		return 0;
2596 
2597 	/* enforce the capability checks at the lsm layer, if needed */
2598 	if (!call_int_hook(inode_xattr_skipcap, name)) {
2599 		rc = cap_inode_removexattr(idmap, dentry, name);
2600 		if (rc)
2601 			return rc;
2602 	}
2603 
2604 	return call_int_hook(inode_removexattr, idmap, dentry, name);
2605 }
2606 
2607 /**
2608  * security_inode_post_removexattr() - Update the inode after a removexattr op
2609  * @dentry: file
2610  * @name: xattr name
2611  *
2612  * Update the inode after a successful removexattr operation.
2613  */
security_inode_post_removexattr(struct dentry * dentry,const char * name)2614 void security_inode_post_removexattr(struct dentry *dentry, const char *name)
2615 {
2616 	if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
2617 		return;
2618 	call_void_hook(inode_post_removexattr, dentry, name);
2619 }
2620 
2621 /**
2622  * security_inode_need_killpriv() - Check if security_inode_killpriv() required
2623  * @dentry: associated dentry
2624  *
2625  * Called when an inode has been changed to determine if
2626  * security_inode_killpriv() should be called.
2627  *
2628  * Return: Return <0 on error to abort the inode change operation, return 0 if
2629  *         security_inode_killpriv() does not need to be called, return >0 if
2630  *         security_inode_killpriv() does need to be called.
2631  */
security_inode_need_killpriv(struct dentry * dentry)2632 int security_inode_need_killpriv(struct dentry *dentry)
2633 {
2634 	return call_int_hook(inode_need_killpriv, dentry);
2635 }
2636 
2637 /**
2638  * security_inode_killpriv() - The setuid bit is removed, update LSM state
2639  * @idmap: idmap of the mount
2640  * @dentry: associated dentry
2641  *
2642  * The @dentry's setuid bit is being removed.  Remove similar security labels.
2643  * Called with the dentry->d_inode->i_mutex held.
2644  *
2645  * Return: Return 0 on success.  If error is returned, then the operation
2646  *         causing setuid bit removal is failed.
2647  */
security_inode_killpriv(struct mnt_idmap * idmap,struct dentry * dentry)2648 int security_inode_killpriv(struct mnt_idmap *idmap,
2649 			    struct dentry *dentry)
2650 {
2651 	return call_int_hook(inode_killpriv, idmap, dentry);
2652 }
2653 
2654 /**
2655  * security_inode_getsecurity() - Get the xattr security label of an inode
2656  * @idmap: idmap of the mount
2657  * @inode: inode
2658  * @name: xattr name
2659  * @buffer: security label buffer
2660  * @alloc: allocation flag
2661  *
2662  * Retrieve a copy of the extended attribute representation of the security
2663  * label associated with @name for @inode via @buffer.  Note that @name is the
2664  * remainder of the attribute name after the security prefix has been removed.
2665  * @alloc is used to specify if the call should return a value via the buffer
2666  * or just the value length.
2667  *
2668  * Return: Returns size of buffer on success.
2669  */
security_inode_getsecurity(struct mnt_idmap * idmap,struct inode * inode,const char * name,void ** buffer,bool alloc)2670 int security_inode_getsecurity(struct mnt_idmap *idmap,
2671 			       struct inode *inode, const char *name,
2672 			       void **buffer, bool alloc)
2673 {
2674 	if (unlikely(IS_PRIVATE(inode)))
2675 		return LSM_RET_DEFAULT(inode_getsecurity);
2676 
2677 	return call_int_hook(inode_getsecurity, idmap, inode, name, buffer,
2678 			     alloc);
2679 }
2680 
2681 /**
2682  * security_inode_setsecurity() - Set the xattr security label of an inode
2683  * @inode: inode
2684  * @name: xattr name
2685  * @value: security label
2686  * @size: length of security label
2687  * @flags: flags
2688  *
2689  * Set the security label associated with @name for @inode from the extended
2690  * attribute value @value.  @size indicates the size of the @value in bytes.
2691  * @flags may be XATTR_CREATE, XATTR_REPLACE, or 0. Note that @name is the
2692  * remainder of the attribute name after the security. prefix has been removed.
2693  *
2694  * Return: Returns 0 on success.
2695  */
security_inode_setsecurity(struct inode * inode,const char * name,const void * value,size_t size,int flags)2696 int security_inode_setsecurity(struct inode *inode, const char *name,
2697 			       const void *value, size_t size, int flags)
2698 {
2699 	if (unlikely(IS_PRIVATE(inode)))
2700 		return LSM_RET_DEFAULT(inode_setsecurity);
2701 
2702 	return call_int_hook(inode_setsecurity, inode, name, value, size,
2703 			     flags);
2704 }
2705 
2706 /**
2707  * security_inode_listsecurity() - List the xattr security label names
2708  * @inode: inode
2709  * @buffer: buffer
2710  * @buffer_size: size of buffer
2711  *
2712  * Copy the extended attribute names for the security labels associated with
2713  * @inode into @buffer.  The maximum size of @buffer is specified by
2714  * @buffer_size.  @buffer may be NULL to request the size of the buffer
2715  * required.
2716  *
2717  * Return: Returns number of bytes used/required on success.
2718  */
security_inode_listsecurity(struct inode * inode,char * buffer,size_t buffer_size)2719 int security_inode_listsecurity(struct inode *inode,
2720 				char *buffer, size_t buffer_size)
2721 {
2722 	if (unlikely(IS_PRIVATE(inode)))
2723 		return 0;
2724 	return call_int_hook(inode_listsecurity, inode, buffer, buffer_size);
2725 }
2726 EXPORT_SYMBOL(security_inode_listsecurity);
2727 
2728 /**
2729  * security_inode_getsecid() - Get an inode's secid
2730  * @inode: inode
2731  * @secid: secid to return
2732  *
2733  * Get the secid associated with the node.  In case of failure, @secid will be
2734  * set to zero.
2735  */
security_inode_getsecid(struct inode * inode,u32 * secid)2736 void security_inode_getsecid(struct inode *inode, u32 *secid)
2737 {
2738 	call_void_hook(inode_getsecid, inode, secid);
2739 }
2740 
2741 /**
2742  * security_inode_copy_up() - Create new creds for an overlayfs copy-up op
2743  * @src: union dentry of copy-up file
2744  * @new: newly created creds
2745  *
2746  * A file is about to be copied up from lower layer to upper layer of overlay
2747  * filesystem. Security module can prepare a set of new creds and modify as
2748  * need be and return new creds. Caller will switch to new creds temporarily to
2749  * create new file and release newly allocated creds.
2750  *
2751  * Return: Returns 0 on success or a negative error code on error.
2752  */
security_inode_copy_up(struct dentry * src,struct cred ** new)2753 int security_inode_copy_up(struct dentry *src, struct cred **new)
2754 {
2755 	return call_int_hook(inode_copy_up, src, new);
2756 }
2757 EXPORT_SYMBOL(security_inode_copy_up);
2758 
2759 /**
2760  * security_inode_copy_up_xattr() - Filter xattrs in an overlayfs copy-up op
2761  * @src: union dentry of copy-up file
2762  * @name: xattr name
2763  *
2764  * Filter the xattrs being copied up when a unioned file is copied up from a
2765  * lower layer to the union/overlay layer.   The caller is responsible for
2766  * reading and writing the xattrs, this hook is merely a filter.
2767  *
2768  * Return: Returns 0 to accept the xattr, -ECANCELED to discard the xattr,
2769  *         -EOPNOTSUPP if the security module does not know about attribute,
2770  *         or a negative error code to abort the copy up.
2771  */
security_inode_copy_up_xattr(struct dentry * src,const char * name)2772 int security_inode_copy_up_xattr(struct dentry *src, const char *name)
2773 {
2774 	int rc;
2775 
2776 	rc = call_int_hook(inode_copy_up_xattr, src, name);
2777 	if (rc != LSM_RET_DEFAULT(inode_copy_up_xattr))
2778 		return rc;
2779 
2780 	return LSM_RET_DEFAULT(inode_copy_up_xattr);
2781 }
2782 EXPORT_SYMBOL(security_inode_copy_up_xattr);
2783 
2784 /**
2785  * security_inode_setintegrity() - Set the inode's integrity data
2786  * @inode: inode
2787  * @type: type of integrity, e.g. hash digest, signature, etc
2788  * @value: the integrity value
2789  * @size: size of the integrity value
2790  *
2791  * Register a verified integrity measurement of a inode with LSMs.
2792  * LSMs should free the previously saved data if @value is NULL.
2793  *
2794  * Return: Returns 0 on success, negative values on failure.
2795  */
security_inode_setintegrity(const struct inode * inode,enum lsm_integrity_type type,const void * value,size_t size)2796 int security_inode_setintegrity(const struct inode *inode,
2797 				enum lsm_integrity_type type, const void *value,
2798 				size_t size)
2799 {
2800 	return call_int_hook(inode_setintegrity, inode, type, value, size);
2801 }
2802 EXPORT_SYMBOL(security_inode_setintegrity);
2803 
2804 /**
2805  * security_kernfs_init_security() - Init LSM context for a kernfs node
2806  * @kn_dir: parent kernfs node
2807  * @kn: the kernfs node to initialize
2808  *
2809  * Initialize the security context of a newly created kernfs node based on its
2810  * own and its parent's attributes.
2811  *
2812  * Return: Returns 0 if permission is granted.
2813  */
security_kernfs_init_security(struct kernfs_node * kn_dir,struct kernfs_node * kn)2814 int security_kernfs_init_security(struct kernfs_node *kn_dir,
2815 				  struct kernfs_node *kn)
2816 {
2817 	return call_int_hook(kernfs_init_security, kn_dir, kn);
2818 }
2819 
2820 /**
2821  * security_file_permission() - Check file permissions
2822  * @file: file
2823  * @mask: requested permissions
2824  *
2825  * Check file permissions before accessing an open file.  This hook is called
2826  * by various operations that read or write files.  A security module can use
2827  * this hook to perform additional checking on these operations, e.g. to
2828  * revalidate permissions on use to support privilege bracketing or policy
2829  * changes.  Notice that this hook is used when the actual read/write
2830  * operations are performed, whereas the inode_security_ops hook is called when
2831  * a file is opened (as well as many other operations).  Although this hook can
2832  * be used to revalidate permissions for various system call operations that
2833  * read or write files, it does not address the revalidation of permissions for
2834  * memory-mapped files.  Security modules must handle this separately if they
2835  * need such revalidation.
2836  *
2837  * Return: Returns 0 if permission is granted.
2838  */
security_file_permission(struct file * file,int mask)2839 int security_file_permission(struct file *file, int mask)
2840 {
2841 	return call_int_hook(file_permission, file, mask);
2842 }
2843 
2844 /**
2845  * security_file_alloc() - Allocate and init a file's LSM blob
2846  * @file: the file
2847  *
2848  * Allocate and attach a security structure to the file->f_security field.  The
2849  * security field is initialized to NULL when the structure is first created.
2850  *
2851  * Return: Return 0 if the hook is successful and permission is granted.
2852  */
security_file_alloc(struct file * file)2853 int security_file_alloc(struct file *file)
2854 {
2855 	int rc = lsm_file_alloc(file);
2856 
2857 	if (rc)
2858 		return rc;
2859 	rc = call_int_hook(file_alloc_security, file);
2860 	if (unlikely(rc))
2861 		security_file_free(file);
2862 	return rc;
2863 }
2864 
2865 /**
2866  * security_file_release() - Perform actions before releasing the file ref
2867  * @file: the file
2868  *
2869  * Perform actions before releasing the last reference to a file.
2870  */
security_file_release(struct file * file)2871 void security_file_release(struct file *file)
2872 {
2873 	call_void_hook(file_release, file);
2874 }
2875 
2876 /**
2877  * security_file_free() - Free a file's LSM blob
2878  * @file: the file
2879  *
2880  * Deallocate and free any security structures stored in file->f_security.
2881  */
security_file_free(struct file * file)2882 void security_file_free(struct file *file)
2883 {
2884 	void *blob;
2885 
2886 	call_void_hook(file_free_security, file);
2887 
2888 	blob = file->f_security;
2889 	if (blob) {
2890 		file->f_security = NULL;
2891 		kmem_cache_free(lsm_file_cache, blob);
2892 	}
2893 }
2894 
2895 /**
2896  * security_file_ioctl() - Check if an ioctl is allowed
2897  * @file: associated file
2898  * @cmd: ioctl cmd
2899  * @arg: ioctl arguments
2900  *
2901  * Check permission for an ioctl operation on @file.  Note that @arg sometimes
2902  * represents a user space pointer; in other cases, it may be a simple integer
2903  * value.  When @arg represents a user space pointer, it should never be used
2904  * by the security module.
2905  *
2906  * Return: Returns 0 if permission is granted.
2907  */
security_file_ioctl(struct file * file,unsigned int cmd,unsigned long arg)2908 int security_file_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
2909 {
2910 	return call_int_hook(file_ioctl, file, cmd, arg);
2911 }
2912 EXPORT_SYMBOL_GPL(security_file_ioctl);
2913 
2914 /**
2915  * security_file_ioctl_compat() - Check if an ioctl is allowed in compat mode
2916  * @file: associated file
2917  * @cmd: ioctl cmd
2918  * @arg: ioctl arguments
2919  *
2920  * Compat version of security_file_ioctl() that correctly handles 32-bit
2921  * processes running on 64-bit kernels.
2922  *
2923  * Return: Returns 0 if permission is granted.
2924  */
security_file_ioctl_compat(struct file * file,unsigned int cmd,unsigned long arg)2925 int security_file_ioctl_compat(struct file *file, unsigned int cmd,
2926 			       unsigned long arg)
2927 {
2928 	return call_int_hook(file_ioctl_compat, file, cmd, arg);
2929 }
2930 EXPORT_SYMBOL_GPL(security_file_ioctl_compat);
2931 
mmap_prot(struct file * file,unsigned long prot)2932 static inline unsigned long mmap_prot(struct file *file, unsigned long prot)
2933 {
2934 	/*
2935 	 * Does we have PROT_READ and does the application expect
2936 	 * it to imply PROT_EXEC?  If not, nothing to talk about...
2937 	 */
2938 	if ((prot & (PROT_READ | PROT_EXEC)) != PROT_READ)
2939 		return prot;
2940 	if (!(current->personality & READ_IMPLIES_EXEC))
2941 		return prot;
2942 	/*
2943 	 * if that's an anonymous mapping, let it.
2944 	 */
2945 	if (!file)
2946 		return prot | PROT_EXEC;
2947 	/*
2948 	 * ditto if it's not on noexec mount, except that on !MMU we need
2949 	 * NOMMU_MAP_EXEC (== VM_MAYEXEC) in this case
2950 	 */
2951 	if (!path_noexec(&file->f_path)) {
2952 #ifndef CONFIG_MMU
2953 		if (file->f_op->mmap_capabilities) {
2954 			unsigned caps = file->f_op->mmap_capabilities(file);
2955 			if (!(caps & NOMMU_MAP_EXEC))
2956 				return prot;
2957 		}
2958 #endif
2959 		return prot | PROT_EXEC;
2960 	}
2961 	/* anything on noexec mount won't get PROT_EXEC */
2962 	return prot;
2963 }
2964 
2965 /**
2966  * security_mmap_file() - Check if mmap'ing a file is allowed
2967  * @file: file
2968  * @prot: protection applied by the kernel
2969  * @flags: flags
2970  *
2971  * Check permissions for a mmap operation.  The @file may be NULL, e.g. if
2972  * mapping anonymous memory.
2973  *
2974  * Return: Returns 0 if permission is granted.
2975  */
security_mmap_file(struct file * file,unsigned long prot,unsigned long flags)2976 int security_mmap_file(struct file *file, unsigned long prot,
2977 		       unsigned long flags)
2978 {
2979 	return call_int_hook(mmap_file, file, prot, mmap_prot(file, prot),
2980 			     flags);
2981 }
2982 
2983 /**
2984  * security_mmap_addr() - Check if mmap'ing an address is allowed
2985  * @addr: address
2986  *
2987  * Check permissions for a mmap operation at @addr.
2988  *
2989  * Return: Returns 0 if permission is granted.
2990  */
security_mmap_addr(unsigned long addr)2991 int security_mmap_addr(unsigned long addr)
2992 {
2993 	return call_int_hook(mmap_addr, addr);
2994 }
2995 
2996 /**
2997  * security_file_mprotect() - Check if changing memory protections is allowed
2998  * @vma: memory region
2999  * @reqprot: application requested protection
3000  * @prot: protection applied by the kernel
3001  *
3002  * Check permissions before changing memory access permissions.
3003  *
3004  * Return: Returns 0 if permission is granted.
3005  */
security_file_mprotect(struct vm_area_struct * vma,unsigned long reqprot,unsigned long prot)3006 int security_file_mprotect(struct vm_area_struct *vma, unsigned long reqprot,
3007 			   unsigned long prot)
3008 {
3009 	return call_int_hook(file_mprotect, vma, reqprot, prot);
3010 }
3011 
3012 /**
3013  * security_file_lock() - Check if a file lock is allowed
3014  * @file: file
3015  * @cmd: lock operation (e.g. F_RDLCK, F_WRLCK)
3016  *
3017  * Check permission before performing file locking operations.  Note the hook
3018  * mediates both flock and fcntl style locks.
3019  *
3020  * Return: Returns 0 if permission is granted.
3021  */
security_file_lock(struct file * file,unsigned int cmd)3022 int security_file_lock(struct file *file, unsigned int cmd)
3023 {
3024 	return call_int_hook(file_lock, file, cmd);
3025 }
3026 
3027 /**
3028  * security_file_fcntl() - Check if fcntl() op is allowed
3029  * @file: file
3030  * @cmd: fcntl command
3031  * @arg: command argument
3032  *
3033  * Check permission before allowing the file operation specified by @cmd from
3034  * being performed on the file @file.  Note that @arg sometimes represents a
3035  * user space pointer; in other cases, it may be a simple integer value.  When
3036  * @arg represents a user space pointer, it should never be used by the
3037  * security module.
3038  *
3039  * Return: Returns 0 if permission is granted.
3040  */
security_file_fcntl(struct file * file,unsigned int cmd,unsigned long arg)3041 int security_file_fcntl(struct file *file, unsigned int cmd, unsigned long arg)
3042 {
3043 	return call_int_hook(file_fcntl, file, cmd, arg);
3044 }
3045 
3046 /**
3047  * security_file_set_fowner() - Set the file owner info in the LSM blob
3048  * @file: the file
3049  *
3050  * Save owner security information (typically from current->security) in
3051  * file->f_security for later use by the send_sigiotask hook.
3052  *
3053  * This hook is called with file->f_owner.lock held.
3054  *
3055  * Return: Returns 0 on success.
3056  */
security_file_set_fowner(struct file * file)3057 void security_file_set_fowner(struct file *file)
3058 {
3059 	call_void_hook(file_set_fowner, file);
3060 }
3061 
3062 /**
3063  * security_file_send_sigiotask() - Check if sending SIGIO/SIGURG is allowed
3064  * @tsk: target task
3065  * @fown: signal sender
3066  * @sig: signal to be sent, SIGIO is sent if 0
3067  *
3068  * Check permission for the file owner @fown to send SIGIO or SIGURG to the
3069  * process @tsk.  Note that this hook is sometimes called from interrupt.  Note
3070  * that the fown_struct, @fown, is never outside the context of a struct file,
3071  * so the file structure (and associated security information) can always be
3072  * obtained: container_of(fown, struct file, f_owner).
3073  *
3074  * Return: Returns 0 if permission is granted.
3075  */
security_file_send_sigiotask(struct task_struct * tsk,struct fown_struct * fown,int sig)3076 int security_file_send_sigiotask(struct task_struct *tsk,
3077 				 struct fown_struct *fown, int sig)
3078 {
3079 	return call_int_hook(file_send_sigiotask, tsk, fown, sig);
3080 }
3081 
3082 /**
3083  * security_file_receive() - Check if receiving a file via IPC is allowed
3084  * @file: file being received
3085  *
3086  * This hook allows security modules to control the ability of a process to
3087  * receive an open file descriptor via socket IPC.
3088  *
3089  * Return: Returns 0 if permission is granted.
3090  */
security_file_receive(struct file * file)3091 int security_file_receive(struct file *file)
3092 {
3093 	return call_int_hook(file_receive, file);
3094 }
3095 
3096 /**
3097  * security_file_open() - Save open() time state for late use by the LSM
3098  * @file:
3099  *
3100  * Save open-time permission checking state for later use upon file_permission,
3101  * and recheck access if anything has changed since inode_permission.
3102  *
3103  * Return: Returns 0 if permission is granted.
3104  */
security_file_open(struct file * file)3105 int security_file_open(struct file *file)
3106 {
3107 	int ret;
3108 
3109 	ret = call_int_hook(file_open, file);
3110 	if (ret)
3111 		return ret;
3112 
3113 	return fsnotify_open_perm(file);
3114 }
3115 
3116 /**
3117  * security_file_post_open() - Evaluate a file after it has been opened
3118  * @file: the file
3119  * @mask: access mask
3120  *
3121  * Evaluate an opened file and the access mask requested with open(). The hook
3122  * is useful for LSMs that require the file content to be available in order to
3123  * make decisions.
3124  *
3125  * Return: Returns 0 if permission is granted.
3126  */
security_file_post_open(struct file * file,int mask)3127 int security_file_post_open(struct file *file, int mask)
3128 {
3129 	return call_int_hook(file_post_open, file, mask);
3130 }
3131 EXPORT_SYMBOL_GPL(security_file_post_open);
3132 
3133 /**
3134  * security_file_truncate() - Check if truncating a file is allowed
3135  * @file: file
3136  *
3137  * Check permission before truncating a file, i.e. using ftruncate.  Note that
3138  * truncation permission may also be checked based on the path, using the
3139  * @path_truncate hook.
3140  *
3141  * Return: Returns 0 if permission is granted.
3142  */
security_file_truncate(struct file * file)3143 int security_file_truncate(struct file *file)
3144 {
3145 	return call_int_hook(file_truncate, file);
3146 }
3147 
3148 /**
3149  * security_task_alloc() - Allocate a task's LSM blob
3150  * @task: the task
3151  * @clone_flags: flags indicating what is being shared
3152  *
3153  * Handle allocation of task-related resources.
3154  *
3155  * Return: Returns a zero on success, negative values on failure.
3156  */
security_task_alloc(struct task_struct * task,unsigned long clone_flags)3157 int security_task_alloc(struct task_struct *task, unsigned long clone_flags)
3158 {
3159 	int rc = lsm_task_alloc(task);
3160 
3161 	if (rc)
3162 		return rc;
3163 	rc = call_int_hook(task_alloc, task, clone_flags);
3164 	if (unlikely(rc))
3165 		security_task_free(task);
3166 	return rc;
3167 }
3168 
3169 /**
3170  * security_task_free() - Free a task's LSM blob and related resources
3171  * @task: task
3172  *
3173  * Handle release of task-related resources.  Note that this can be called from
3174  * interrupt context.
3175  */
security_task_free(struct task_struct * task)3176 void security_task_free(struct task_struct *task)
3177 {
3178 	call_void_hook(task_free, task);
3179 
3180 	kfree(task->security);
3181 	task->security = NULL;
3182 }
3183 
3184 /**
3185  * security_cred_alloc_blank() - Allocate the min memory to allow cred_transfer
3186  * @cred: credentials
3187  * @gfp: gfp flags
3188  *
3189  * Only allocate sufficient memory and attach to @cred such that
3190  * cred_transfer() will not get ENOMEM.
3191  *
3192  * Return: Returns 0 on success, negative values on failure.
3193  */
security_cred_alloc_blank(struct cred * cred,gfp_t gfp)3194 int security_cred_alloc_blank(struct cred *cred, gfp_t gfp)
3195 {
3196 	int rc = lsm_cred_alloc(cred, gfp);
3197 
3198 	if (rc)
3199 		return rc;
3200 
3201 	rc = call_int_hook(cred_alloc_blank, cred, gfp);
3202 	if (unlikely(rc))
3203 		security_cred_free(cred);
3204 	return rc;
3205 }
3206 
3207 /**
3208  * security_cred_free() - Free the cred's LSM blob and associated resources
3209  * @cred: credentials
3210  *
3211  * Deallocate and clear the cred->security field in a set of credentials.
3212  */
security_cred_free(struct cred * cred)3213 void security_cred_free(struct cred *cred)
3214 {
3215 	/*
3216 	 * There is a failure case in prepare_creds() that
3217 	 * may result in a call here with ->security being NULL.
3218 	 */
3219 	if (unlikely(cred->security == NULL))
3220 		return;
3221 
3222 	call_void_hook(cred_free, cred);
3223 
3224 	kfree(cred->security);
3225 	cred->security = NULL;
3226 }
3227 
3228 /**
3229  * security_prepare_creds() - Prepare a new set of credentials
3230  * @new: new credentials
3231  * @old: original credentials
3232  * @gfp: gfp flags
3233  *
3234  * Prepare a new set of credentials by copying the data from the old set.
3235  *
3236  * Return: Returns 0 on success, negative values on failure.
3237  */
security_prepare_creds(struct cred * new,const struct cred * old,gfp_t gfp)3238 int security_prepare_creds(struct cred *new, const struct cred *old, gfp_t gfp)
3239 {
3240 	int rc = lsm_cred_alloc(new, gfp);
3241 
3242 	if (rc)
3243 		return rc;
3244 
3245 	rc = call_int_hook(cred_prepare, new, old, gfp);
3246 	if (unlikely(rc))
3247 		security_cred_free(new);
3248 	return rc;
3249 }
3250 
3251 /**
3252  * security_transfer_creds() - Transfer creds
3253  * @new: target credentials
3254  * @old: original credentials
3255  *
3256  * Transfer data from original creds to new creds.
3257  */
security_transfer_creds(struct cred * new,const struct cred * old)3258 void security_transfer_creds(struct cred *new, const struct cred *old)
3259 {
3260 	call_void_hook(cred_transfer, new, old);
3261 }
3262 
3263 /**
3264  * security_cred_getsecid() - Get the secid from a set of credentials
3265  * @c: credentials
3266  * @secid: secid value
3267  *
3268  * Retrieve the security identifier of the cred structure @c.  In case of
3269  * failure, @secid will be set to zero.
3270  */
security_cred_getsecid(const struct cred * c,u32 * secid)3271 void security_cred_getsecid(const struct cred *c, u32 *secid)
3272 {
3273 	*secid = 0;
3274 	call_void_hook(cred_getsecid, c, secid);
3275 }
3276 EXPORT_SYMBOL(security_cred_getsecid);
3277 
3278 /**
3279  * security_kernel_act_as() - Set the kernel credentials to act as secid
3280  * @new: credentials
3281  * @secid: secid
3282  *
3283  * Set the credentials for a kernel service to act as (subjective context).
3284  * The current task must be the one that nominated @secid.
3285  *
3286  * Return: Returns 0 if successful.
3287  */
security_kernel_act_as(struct cred * new,u32 secid)3288 int security_kernel_act_as(struct cred *new, u32 secid)
3289 {
3290 	return call_int_hook(kernel_act_as, new, secid);
3291 }
3292 
3293 /**
3294  * security_kernel_create_files_as() - Set file creation context using an inode
3295  * @new: target credentials
3296  * @inode: reference inode
3297  *
3298  * Set the file creation context in a set of credentials to be the same as the
3299  * objective context of the specified inode.  The current task must be the one
3300  * that nominated @inode.
3301  *
3302  * Return: Returns 0 if successful.
3303  */
security_kernel_create_files_as(struct cred * new,struct inode * inode)3304 int security_kernel_create_files_as(struct cred *new, struct inode *inode)
3305 {
3306 	return call_int_hook(kernel_create_files_as, new, inode);
3307 }
3308 
3309 /**
3310  * security_kernel_module_request() - Check if loading a module is allowed
3311  * @kmod_name: module name
3312  *
3313  * Ability to trigger the kernel to automatically upcall to userspace for
3314  * userspace to load a kernel module with the given name.
3315  *
3316  * Return: Returns 0 if successful.
3317  */
security_kernel_module_request(char * kmod_name)3318 int security_kernel_module_request(char *kmod_name)
3319 {
3320 	return call_int_hook(kernel_module_request, kmod_name);
3321 }
3322 
3323 /**
3324  * security_kernel_read_file() - Read a file specified by userspace
3325  * @file: file
3326  * @id: file identifier
3327  * @contents: trust if security_kernel_post_read_file() will be called
3328  *
3329  * Read a file specified by userspace.
3330  *
3331  * Return: Returns 0 if permission is granted.
3332  */
security_kernel_read_file(struct file * file,enum kernel_read_file_id id,bool contents)3333 int security_kernel_read_file(struct file *file, enum kernel_read_file_id id,
3334 			      bool contents)
3335 {
3336 	return call_int_hook(kernel_read_file, file, id, contents);
3337 }
3338 EXPORT_SYMBOL_GPL(security_kernel_read_file);
3339 
3340 /**
3341  * security_kernel_post_read_file() - Read a file specified by userspace
3342  * @file: file
3343  * @buf: file contents
3344  * @size: size of file contents
3345  * @id: file identifier
3346  *
3347  * Read a file specified by userspace.  This must be paired with a prior call
3348  * to security_kernel_read_file() call that indicated this hook would also be
3349  * called, see security_kernel_read_file() for more information.
3350  *
3351  * Return: Returns 0 if permission is granted.
3352  */
security_kernel_post_read_file(struct file * file,char * buf,loff_t size,enum kernel_read_file_id id)3353 int security_kernel_post_read_file(struct file *file, char *buf, loff_t size,
3354 				   enum kernel_read_file_id id)
3355 {
3356 	return call_int_hook(kernel_post_read_file, file, buf, size, id);
3357 }
3358 EXPORT_SYMBOL_GPL(security_kernel_post_read_file);
3359 
3360 /**
3361  * security_kernel_load_data() - Load data provided by userspace
3362  * @id: data identifier
3363  * @contents: true if security_kernel_post_load_data() will be called
3364  *
3365  * Load data provided by userspace.
3366  *
3367  * Return: Returns 0 if permission is granted.
3368  */
security_kernel_load_data(enum kernel_load_data_id id,bool contents)3369 int security_kernel_load_data(enum kernel_load_data_id id, bool contents)
3370 {
3371 	return call_int_hook(kernel_load_data, id, contents);
3372 }
3373 EXPORT_SYMBOL_GPL(security_kernel_load_data);
3374 
3375 /**
3376  * security_kernel_post_load_data() - Load userspace data from a non-file source
3377  * @buf: data
3378  * @size: size of data
3379  * @id: data identifier
3380  * @description: text description of data, specific to the id value
3381  *
3382  * Load data provided by a non-file source (usually userspace buffer).  This
3383  * must be paired with a prior security_kernel_load_data() call that indicated
3384  * this hook would also be called, see security_kernel_load_data() for more
3385  * information.
3386  *
3387  * Return: Returns 0 if permission is granted.
3388  */
security_kernel_post_load_data(char * buf,loff_t size,enum kernel_load_data_id id,char * description)3389 int security_kernel_post_load_data(char *buf, loff_t size,
3390 				   enum kernel_load_data_id id,
3391 				   char *description)
3392 {
3393 	return call_int_hook(kernel_post_load_data, buf, size, id, description);
3394 }
3395 EXPORT_SYMBOL_GPL(security_kernel_post_load_data);
3396 
3397 /**
3398  * security_task_fix_setuid() - Update LSM with new user id attributes
3399  * @new: updated credentials
3400  * @old: credentials being replaced
3401  * @flags: LSM_SETID_* flag values
3402  *
3403  * Update the module's state after setting one or more of the user identity
3404  * attributes of the current process.  The @flags parameter indicates which of
3405  * the set*uid system calls invoked this hook.  If @new is the set of
3406  * credentials that will be installed.  Modifications should be made to this
3407  * rather than to @current->cred.
3408  *
3409  * Return: Returns 0 on success.
3410  */
security_task_fix_setuid(struct cred * new,const struct cred * old,int flags)3411 int security_task_fix_setuid(struct cred *new, const struct cred *old,
3412 			     int flags)
3413 {
3414 	return call_int_hook(task_fix_setuid, new, old, flags);
3415 }
3416 
3417 /**
3418  * security_task_fix_setgid() - Update LSM with new group id attributes
3419  * @new: updated credentials
3420  * @old: credentials being replaced
3421  * @flags: LSM_SETID_* flag value
3422  *
3423  * Update the module's state after setting one or more of the group identity
3424  * attributes of the current process.  The @flags parameter indicates which of
3425  * the set*gid system calls invoked this hook.  @new is the set of credentials
3426  * that will be installed.  Modifications should be made to this rather than to
3427  * @current->cred.
3428  *
3429  * Return: Returns 0 on success.
3430  */
security_task_fix_setgid(struct cred * new,const struct cred * old,int flags)3431 int security_task_fix_setgid(struct cred *new, const struct cred *old,
3432 			     int flags)
3433 {
3434 	return call_int_hook(task_fix_setgid, new, old, flags);
3435 }
3436 
3437 /**
3438  * security_task_fix_setgroups() - Update LSM with new supplementary groups
3439  * @new: updated credentials
3440  * @old: credentials being replaced
3441  *
3442  * Update the module's state after setting the supplementary group identity
3443  * attributes of the current process.  @new is the set of credentials that will
3444  * be installed.  Modifications should be made to this rather than to
3445  * @current->cred.
3446  *
3447  * Return: Returns 0 on success.
3448  */
security_task_fix_setgroups(struct cred * new,const struct cred * old)3449 int security_task_fix_setgroups(struct cred *new, const struct cred *old)
3450 {
3451 	return call_int_hook(task_fix_setgroups, new, old);
3452 }
3453 
3454 /**
3455  * security_task_setpgid() - Check if setting the pgid is allowed
3456  * @p: task being modified
3457  * @pgid: new pgid
3458  *
3459  * Check permission before setting the process group identifier of the process
3460  * @p to @pgid.
3461  *
3462  * Return: Returns 0 if permission is granted.
3463  */
security_task_setpgid(struct task_struct * p,pid_t pgid)3464 int security_task_setpgid(struct task_struct *p, pid_t pgid)
3465 {
3466 	return call_int_hook(task_setpgid, p, pgid);
3467 }
3468 
3469 /**
3470  * security_task_getpgid() - Check if getting the pgid is allowed
3471  * @p: task
3472  *
3473  * Check permission before getting the process group identifier of the process
3474  * @p.
3475  *
3476  * Return: Returns 0 if permission is granted.
3477  */
security_task_getpgid(struct task_struct * p)3478 int security_task_getpgid(struct task_struct *p)
3479 {
3480 	return call_int_hook(task_getpgid, p);
3481 }
3482 
3483 /**
3484  * security_task_getsid() - Check if getting the session id is allowed
3485  * @p: task
3486  *
3487  * Check permission before getting the session identifier of the process @p.
3488  *
3489  * Return: Returns 0 if permission is granted.
3490  */
security_task_getsid(struct task_struct * p)3491 int security_task_getsid(struct task_struct *p)
3492 {
3493 	return call_int_hook(task_getsid, p);
3494 }
3495 
3496 /**
3497  * security_current_getsecid_subj() - Get the current task's subjective secid
3498  * @secid: secid value
3499  *
3500  * Retrieve the subjective security identifier of the current task and return
3501  * it in @secid.  In case of failure, @secid will be set to zero.
3502  */
security_current_getsecid_subj(u32 * secid)3503 void security_current_getsecid_subj(u32 *secid)
3504 {
3505 	*secid = 0;
3506 	call_void_hook(current_getsecid_subj, secid);
3507 }
3508 EXPORT_SYMBOL(security_current_getsecid_subj);
3509 
3510 /**
3511  * security_task_getsecid_obj() - Get a task's objective secid
3512  * @p: target task
3513  * @secid: secid value
3514  *
3515  * Retrieve the objective security identifier of the task_struct in @p and
3516  * return it in @secid. In case of failure, @secid will be set to zero.
3517  */
security_task_getsecid_obj(struct task_struct * p,u32 * secid)3518 void security_task_getsecid_obj(struct task_struct *p, u32 *secid)
3519 {
3520 	*secid = 0;
3521 	call_void_hook(task_getsecid_obj, p, secid);
3522 }
3523 EXPORT_SYMBOL(security_task_getsecid_obj);
3524 
3525 /**
3526  * security_task_setnice() - Check if setting a task's nice value is allowed
3527  * @p: target task
3528  * @nice: nice value
3529  *
3530  * Check permission before setting the nice value of @p to @nice.
3531  *
3532  * Return: Returns 0 if permission is granted.
3533  */
security_task_setnice(struct task_struct * p,int nice)3534 int security_task_setnice(struct task_struct *p, int nice)
3535 {
3536 	return call_int_hook(task_setnice, p, nice);
3537 }
3538 
3539 /**
3540  * security_task_setioprio() - Check if setting a task's ioprio is allowed
3541  * @p: target task
3542  * @ioprio: ioprio value
3543  *
3544  * Check permission before setting the ioprio value of @p to @ioprio.
3545  *
3546  * Return: Returns 0 if permission is granted.
3547  */
security_task_setioprio(struct task_struct * p,int ioprio)3548 int security_task_setioprio(struct task_struct *p, int ioprio)
3549 {
3550 	return call_int_hook(task_setioprio, p, ioprio);
3551 }
3552 
3553 /**
3554  * security_task_getioprio() - Check if getting a task's ioprio is allowed
3555  * @p: task
3556  *
3557  * Check permission before getting the ioprio value of @p.
3558  *
3559  * Return: Returns 0 if permission is granted.
3560  */
security_task_getioprio(struct task_struct * p)3561 int security_task_getioprio(struct task_struct *p)
3562 {
3563 	return call_int_hook(task_getioprio, p);
3564 }
3565 
3566 /**
3567  * security_task_prlimit() - Check if get/setting resources limits is allowed
3568  * @cred: current task credentials
3569  * @tcred: target task credentials
3570  * @flags: LSM_PRLIMIT_* flag bits indicating a get/set/both
3571  *
3572  * Check permission before getting and/or setting the resource limits of
3573  * another task.
3574  *
3575  * Return: Returns 0 if permission is granted.
3576  */
security_task_prlimit(const struct cred * cred,const struct cred * tcred,unsigned int flags)3577 int security_task_prlimit(const struct cred *cred, const struct cred *tcred,
3578 			  unsigned int flags)
3579 {
3580 	return call_int_hook(task_prlimit, cred, tcred, flags);
3581 }
3582 
3583 /**
3584  * security_task_setrlimit() - Check if setting a new rlimit value is allowed
3585  * @p: target task's group leader
3586  * @resource: resource whose limit is being set
3587  * @new_rlim: new resource limit
3588  *
3589  * Check permission before setting the resource limits of process @p for
3590  * @resource to @new_rlim.  The old resource limit values can be examined by
3591  * dereferencing (p->signal->rlim + resource).
3592  *
3593  * Return: Returns 0 if permission is granted.
3594  */
security_task_setrlimit(struct task_struct * p,unsigned int resource,struct rlimit * new_rlim)3595 int security_task_setrlimit(struct task_struct *p, unsigned int resource,
3596 			    struct rlimit *new_rlim)
3597 {
3598 	return call_int_hook(task_setrlimit, p, resource, new_rlim);
3599 }
3600 
3601 /**
3602  * security_task_setscheduler() - Check if setting sched policy/param is allowed
3603  * @p: target task
3604  *
3605  * Check permission before setting scheduling policy and/or parameters of
3606  * process @p.
3607  *
3608  * Return: Returns 0 if permission is granted.
3609  */
security_task_setscheduler(struct task_struct * p)3610 int security_task_setscheduler(struct task_struct *p)
3611 {
3612 	return call_int_hook(task_setscheduler, p);
3613 }
3614 
3615 /**
3616  * security_task_getscheduler() - Check if getting scheduling info is allowed
3617  * @p: target task
3618  *
3619  * Check permission before obtaining scheduling information for process @p.
3620  *
3621  * Return: Returns 0 if permission is granted.
3622  */
security_task_getscheduler(struct task_struct * p)3623 int security_task_getscheduler(struct task_struct *p)
3624 {
3625 	return call_int_hook(task_getscheduler, p);
3626 }
3627 
3628 /**
3629  * security_task_movememory() - Check if moving memory is allowed
3630  * @p: task
3631  *
3632  * Check permission before moving memory owned by process @p.
3633  *
3634  * Return: Returns 0 if permission is granted.
3635  */
security_task_movememory(struct task_struct * p)3636 int security_task_movememory(struct task_struct *p)
3637 {
3638 	return call_int_hook(task_movememory, p);
3639 }
3640 
3641 /**
3642  * security_task_kill() - Check if sending a signal is allowed
3643  * @p: target process
3644  * @info: signal information
3645  * @sig: signal value
3646  * @cred: credentials of the signal sender, NULL if @current
3647  *
3648  * Check permission before sending signal @sig to @p.  @info can be NULL, the
3649  * constant 1, or a pointer to a kernel_siginfo structure.  If @info is 1 or
3650  * SI_FROMKERNEL(info) is true, then the signal should be viewed as coming from
3651  * the kernel and should typically be permitted.  SIGIO signals are handled
3652  * separately by the send_sigiotask hook in file_security_ops.
3653  *
3654  * Return: Returns 0 if permission is granted.
3655  */
security_task_kill(struct task_struct * p,struct kernel_siginfo * info,int sig,const struct cred * cred)3656 int security_task_kill(struct task_struct *p, struct kernel_siginfo *info,
3657 		       int sig, const struct cred *cred)
3658 {
3659 	return call_int_hook(task_kill, p, info, sig, cred);
3660 }
3661 
3662 /**
3663  * security_task_prctl() - Check if a prctl op is allowed
3664  * @option: operation
3665  * @arg2: argument
3666  * @arg3: argument
3667  * @arg4: argument
3668  * @arg5: argument
3669  *
3670  * Check permission before performing a process control operation on the
3671  * current process.
3672  *
3673  * Return: Return -ENOSYS if no-one wanted to handle this op, any other value
3674  *         to cause prctl() to return immediately with that value.
3675  */
security_task_prctl(int option,unsigned long arg2,unsigned long arg3,unsigned long arg4,unsigned long arg5)3676 int security_task_prctl(int option, unsigned long arg2, unsigned long arg3,
3677 			unsigned long arg4, unsigned long arg5)
3678 {
3679 	int thisrc;
3680 	int rc = LSM_RET_DEFAULT(task_prctl);
3681 	struct lsm_static_call *scall;
3682 
3683 	lsm_for_each_hook(scall, task_prctl) {
3684 		thisrc = scall->hl->hook.task_prctl(option, arg2, arg3, arg4, arg5);
3685 		if (thisrc != LSM_RET_DEFAULT(task_prctl)) {
3686 			rc = thisrc;
3687 			if (thisrc != 0)
3688 				break;
3689 		}
3690 	}
3691 	return rc;
3692 }
3693 
3694 /**
3695  * security_task_to_inode() - Set the security attributes of a task's inode
3696  * @p: task
3697  * @inode: inode
3698  *
3699  * Set the security attributes for an inode based on an associated task's
3700  * security attributes, e.g. for /proc/pid inodes.
3701  */
security_task_to_inode(struct task_struct * p,struct inode * inode)3702 void security_task_to_inode(struct task_struct *p, struct inode *inode)
3703 {
3704 	call_void_hook(task_to_inode, p, inode);
3705 }
3706 
3707 /**
3708  * security_create_user_ns() - Check if creating a new userns is allowed
3709  * @cred: prepared creds
3710  *
3711  * Check permission prior to creating a new user namespace.
3712  *
3713  * Return: Returns 0 if successful, otherwise < 0 error code.
3714  */
security_create_user_ns(const struct cred * cred)3715 int security_create_user_ns(const struct cred *cred)
3716 {
3717 	return call_int_hook(userns_create, cred);
3718 }
3719 
3720 /**
3721  * security_ipc_permission() - Check if sysv ipc access is allowed
3722  * @ipcp: ipc permission structure
3723  * @flag: requested permissions
3724  *
3725  * Check permissions for access to IPC.
3726  *
3727  * Return: Returns 0 if permission is granted.
3728  */
security_ipc_permission(struct kern_ipc_perm * ipcp,short flag)3729 int security_ipc_permission(struct kern_ipc_perm *ipcp, short flag)
3730 {
3731 	return call_int_hook(ipc_permission, ipcp, flag);
3732 }
3733 
3734 /**
3735  * security_ipc_getsecid() - Get the sysv ipc object's secid
3736  * @ipcp: ipc permission structure
3737  * @secid: secid pointer
3738  *
3739  * Get the secid associated with the ipc object.  In case of failure, @secid
3740  * will be set to zero.
3741  */
security_ipc_getsecid(struct kern_ipc_perm * ipcp,u32 * secid)3742 void security_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid)
3743 {
3744 	*secid = 0;
3745 	call_void_hook(ipc_getsecid, ipcp, secid);
3746 }
3747 
3748 /**
3749  * security_msg_msg_alloc() - Allocate a sysv ipc message LSM blob
3750  * @msg: message structure
3751  *
3752  * Allocate and attach a security structure to the msg->security field.  The
3753  * security field is initialized to NULL when the structure is first created.
3754  *
3755  * Return: Return 0 if operation was successful and permission is granted.
3756  */
security_msg_msg_alloc(struct msg_msg * msg)3757 int security_msg_msg_alloc(struct msg_msg *msg)
3758 {
3759 	int rc = lsm_msg_msg_alloc(msg);
3760 
3761 	if (unlikely(rc))
3762 		return rc;
3763 	rc = call_int_hook(msg_msg_alloc_security, msg);
3764 	if (unlikely(rc))
3765 		security_msg_msg_free(msg);
3766 	return rc;
3767 }
3768 
3769 /**
3770  * security_msg_msg_free() - Free a sysv ipc message LSM blob
3771  * @msg: message structure
3772  *
3773  * Deallocate the security structure for this message.
3774  */
security_msg_msg_free(struct msg_msg * msg)3775 void security_msg_msg_free(struct msg_msg *msg)
3776 {
3777 	call_void_hook(msg_msg_free_security, msg);
3778 	kfree(msg->security);
3779 	msg->security = NULL;
3780 }
3781 
3782 /**
3783  * security_msg_queue_alloc() - Allocate a sysv ipc msg queue LSM blob
3784  * @msq: sysv ipc permission structure
3785  *
3786  * Allocate and attach a security structure to @msg. The security field is
3787  * initialized to NULL when the structure is first created.
3788  *
3789  * Return: Returns 0 if operation was successful and permission is granted.
3790  */
security_msg_queue_alloc(struct kern_ipc_perm * msq)3791 int security_msg_queue_alloc(struct kern_ipc_perm *msq)
3792 {
3793 	int rc = lsm_ipc_alloc(msq);
3794 
3795 	if (unlikely(rc))
3796 		return rc;
3797 	rc = call_int_hook(msg_queue_alloc_security, msq);
3798 	if (unlikely(rc))
3799 		security_msg_queue_free(msq);
3800 	return rc;
3801 }
3802 
3803 /**
3804  * security_msg_queue_free() - Free a sysv ipc msg queue LSM blob
3805  * @msq: sysv ipc permission structure
3806  *
3807  * Deallocate security field @perm->security for the message queue.
3808  */
security_msg_queue_free(struct kern_ipc_perm * msq)3809 void security_msg_queue_free(struct kern_ipc_perm *msq)
3810 {
3811 	call_void_hook(msg_queue_free_security, msq);
3812 	kfree(msq->security);
3813 	msq->security = NULL;
3814 }
3815 
3816 /**
3817  * security_msg_queue_associate() - Check if a msg queue operation is allowed
3818  * @msq: sysv ipc permission structure
3819  * @msqflg: operation flags
3820  *
3821  * Check permission when a message queue is requested through the msgget system
3822  * call. This hook is only called when returning the message queue identifier
3823  * for an existing message queue, not when a new message queue is created.
3824  *
3825  * Return: Return 0 if permission is granted.
3826  */
security_msg_queue_associate(struct kern_ipc_perm * msq,int msqflg)3827 int security_msg_queue_associate(struct kern_ipc_perm *msq, int msqflg)
3828 {
3829 	return call_int_hook(msg_queue_associate, msq, msqflg);
3830 }
3831 
3832 /**
3833  * security_msg_queue_msgctl() - Check if a msg queue operation is allowed
3834  * @msq: sysv ipc permission structure
3835  * @cmd: operation
3836  *
3837  * Check permission when a message control operation specified by @cmd is to be
3838  * performed on the message queue with permissions.
3839  *
3840  * Return: Returns 0 if permission is granted.
3841  */
security_msg_queue_msgctl(struct kern_ipc_perm * msq,int cmd)3842 int security_msg_queue_msgctl(struct kern_ipc_perm *msq, int cmd)
3843 {
3844 	return call_int_hook(msg_queue_msgctl, msq, cmd);
3845 }
3846 
3847 /**
3848  * security_msg_queue_msgsnd() - Check if sending a sysv ipc message is allowed
3849  * @msq: sysv ipc permission structure
3850  * @msg: message
3851  * @msqflg: operation flags
3852  *
3853  * Check permission before a message, @msg, is enqueued on the message queue
3854  * with permissions specified in @msq.
3855  *
3856  * Return: Returns 0 if permission is granted.
3857  */
security_msg_queue_msgsnd(struct kern_ipc_perm * msq,struct msg_msg * msg,int msqflg)3858 int security_msg_queue_msgsnd(struct kern_ipc_perm *msq,
3859 			      struct msg_msg *msg, int msqflg)
3860 {
3861 	return call_int_hook(msg_queue_msgsnd, msq, msg, msqflg);
3862 }
3863 
3864 /**
3865  * security_msg_queue_msgrcv() - Check if receiving a sysv ipc msg is allowed
3866  * @msq: sysv ipc permission structure
3867  * @msg: message
3868  * @target: target task
3869  * @type: type of message requested
3870  * @mode: operation flags
3871  *
3872  * Check permission before a message, @msg, is removed from the message	queue.
3873  * The @target task structure contains a pointer to the process that will be
3874  * receiving the message (not equal to the current process when inline receives
3875  * are being performed).
3876  *
3877  * Return: Returns 0 if permission is granted.
3878  */
security_msg_queue_msgrcv(struct kern_ipc_perm * msq,struct msg_msg * msg,struct task_struct * target,long type,int mode)3879 int security_msg_queue_msgrcv(struct kern_ipc_perm *msq, struct msg_msg *msg,
3880 			      struct task_struct *target, long type, int mode)
3881 {
3882 	return call_int_hook(msg_queue_msgrcv, msq, msg, target, type, mode);
3883 }
3884 
3885 /**
3886  * security_shm_alloc() - Allocate a sysv shm LSM blob
3887  * @shp: sysv ipc permission structure
3888  *
3889  * Allocate and attach a security structure to the @shp security field.  The
3890  * security field is initialized to NULL when the structure is first created.
3891  *
3892  * Return: Returns 0 if operation was successful and permission is granted.
3893  */
security_shm_alloc(struct kern_ipc_perm * shp)3894 int security_shm_alloc(struct kern_ipc_perm *shp)
3895 {
3896 	int rc = lsm_ipc_alloc(shp);
3897 
3898 	if (unlikely(rc))
3899 		return rc;
3900 	rc = call_int_hook(shm_alloc_security, shp);
3901 	if (unlikely(rc))
3902 		security_shm_free(shp);
3903 	return rc;
3904 }
3905 
3906 /**
3907  * security_shm_free() - Free a sysv shm LSM blob
3908  * @shp: sysv ipc permission structure
3909  *
3910  * Deallocate the security structure @perm->security for the memory segment.
3911  */
security_shm_free(struct kern_ipc_perm * shp)3912 void security_shm_free(struct kern_ipc_perm *shp)
3913 {
3914 	call_void_hook(shm_free_security, shp);
3915 	kfree(shp->security);
3916 	shp->security = NULL;
3917 }
3918 
3919 /**
3920  * security_shm_associate() - Check if a sysv shm operation is allowed
3921  * @shp: sysv ipc permission structure
3922  * @shmflg: operation flags
3923  *
3924  * Check permission when a shared memory region is requested through the shmget
3925  * system call. This hook is only called when returning the shared memory
3926  * region identifier for an existing region, not when a new shared memory
3927  * region is created.
3928  *
3929  * Return: Returns 0 if permission is granted.
3930  */
security_shm_associate(struct kern_ipc_perm * shp,int shmflg)3931 int security_shm_associate(struct kern_ipc_perm *shp, int shmflg)
3932 {
3933 	return call_int_hook(shm_associate, shp, shmflg);
3934 }
3935 
3936 /**
3937  * security_shm_shmctl() - Check if a sysv shm operation is allowed
3938  * @shp: sysv ipc permission structure
3939  * @cmd: operation
3940  *
3941  * Check permission when a shared memory control operation specified by @cmd is
3942  * to be performed on the shared memory region with permissions in @shp.
3943  *
3944  * Return: Return 0 if permission is granted.
3945  */
security_shm_shmctl(struct kern_ipc_perm * shp,int cmd)3946 int security_shm_shmctl(struct kern_ipc_perm *shp, int cmd)
3947 {
3948 	return call_int_hook(shm_shmctl, shp, cmd);
3949 }
3950 
3951 /**
3952  * security_shm_shmat() - Check if a sysv shm attach operation is allowed
3953  * @shp: sysv ipc permission structure
3954  * @shmaddr: address of memory region to attach
3955  * @shmflg: operation flags
3956  *
3957  * Check permissions prior to allowing the shmat system call to attach the
3958  * shared memory segment with permissions @shp to the data segment of the
3959  * calling process. The attaching address is specified by @shmaddr.
3960  *
3961  * Return: Returns 0 if permission is granted.
3962  */
security_shm_shmat(struct kern_ipc_perm * shp,char __user * shmaddr,int shmflg)3963 int security_shm_shmat(struct kern_ipc_perm *shp,
3964 		       char __user *shmaddr, int shmflg)
3965 {
3966 	return call_int_hook(shm_shmat, shp, shmaddr, shmflg);
3967 }
3968 
3969 /**
3970  * security_sem_alloc() - Allocate a sysv semaphore LSM blob
3971  * @sma: sysv ipc permission structure
3972  *
3973  * Allocate and attach a security structure to the @sma security field. The
3974  * security field is initialized to NULL when the structure is first created.
3975  *
3976  * Return: Returns 0 if operation was successful and permission is granted.
3977  */
security_sem_alloc(struct kern_ipc_perm * sma)3978 int security_sem_alloc(struct kern_ipc_perm *sma)
3979 {
3980 	int rc = lsm_ipc_alloc(sma);
3981 
3982 	if (unlikely(rc))
3983 		return rc;
3984 	rc = call_int_hook(sem_alloc_security, sma);
3985 	if (unlikely(rc))
3986 		security_sem_free(sma);
3987 	return rc;
3988 }
3989 
3990 /**
3991  * security_sem_free() - Free a sysv semaphore LSM blob
3992  * @sma: sysv ipc permission structure
3993  *
3994  * Deallocate security structure @sma->security for the semaphore.
3995  */
security_sem_free(struct kern_ipc_perm * sma)3996 void security_sem_free(struct kern_ipc_perm *sma)
3997 {
3998 	call_void_hook(sem_free_security, sma);
3999 	kfree(sma->security);
4000 	sma->security = NULL;
4001 }
4002 
4003 /**
4004  * security_sem_associate() - Check if a sysv semaphore operation is allowed
4005  * @sma: sysv ipc permission structure
4006  * @semflg: operation flags
4007  *
4008  * Check permission when a semaphore is requested through the semget system
4009  * call. This hook is only called when returning the semaphore identifier for
4010  * an existing semaphore, not when a new one must be created.
4011  *
4012  * Return: Returns 0 if permission is granted.
4013  */
security_sem_associate(struct kern_ipc_perm * sma,int semflg)4014 int security_sem_associate(struct kern_ipc_perm *sma, int semflg)
4015 {
4016 	return call_int_hook(sem_associate, sma, semflg);
4017 }
4018 
4019 /**
4020  * security_sem_semctl() - Check if a sysv semaphore operation is allowed
4021  * @sma: sysv ipc permission structure
4022  * @cmd: operation
4023  *
4024  * Check permission when a semaphore operation specified by @cmd is to be
4025  * performed on the semaphore.
4026  *
4027  * Return: Returns 0 if permission is granted.
4028  */
security_sem_semctl(struct kern_ipc_perm * sma,int cmd)4029 int security_sem_semctl(struct kern_ipc_perm *sma, int cmd)
4030 {
4031 	return call_int_hook(sem_semctl, sma, cmd);
4032 }
4033 
4034 /**
4035  * security_sem_semop() - Check if a sysv semaphore operation is allowed
4036  * @sma: sysv ipc permission structure
4037  * @sops: operations to perform
4038  * @nsops: number of operations
4039  * @alter: flag indicating changes will be made
4040  *
4041  * Check permissions before performing operations on members of the semaphore
4042  * set. If the @alter flag is nonzero, the semaphore set may be modified.
4043  *
4044  * Return: Returns 0 if permission is granted.
4045  */
security_sem_semop(struct kern_ipc_perm * sma,struct sembuf * sops,unsigned nsops,int alter)4046 int security_sem_semop(struct kern_ipc_perm *sma, struct sembuf *sops,
4047 		       unsigned nsops, int alter)
4048 {
4049 	return call_int_hook(sem_semop, sma, sops, nsops, alter);
4050 }
4051 
4052 /**
4053  * security_d_instantiate() - Populate an inode's LSM state based on a dentry
4054  * @dentry: dentry
4055  * @inode: inode
4056  *
4057  * Fill in @inode security information for a @dentry if allowed.
4058  */
security_d_instantiate(struct dentry * dentry,struct inode * inode)4059 void security_d_instantiate(struct dentry *dentry, struct inode *inode)
4060 {
4061 	if (unlikely(inode && IS_PRIVATE(inode)))
4062 		return;
4063 	call_void_hook(d_instantiate, dentry, inode);
4064 }
4065 EXPORT_SYMBOL(security_d_instantiate);
4066 
4067 /*
4068  * Please keep this in sync with it's counterpart in security/lsm_syscalls.c
4069  */
4070 
4071 /**
4072  * security_getselfattr - Read an LSM attribute of the current process.
4073  * @attr: which attribute to return
4074  * @uctx: the user-space destination for the information, or NULL
4075  * @size: pointer to the size of space available to receive the data
4076  * @flags: special handling options. LSM_FLAG_SINGLE indicates that only
4077  * attributes associated with the LSM identified in the passed @ctx be
4078  * reported.
4079  *
4080  * A NULL value for @uctx can be used to get both the number of attributes
4081  * and the size of the data.
4082  *
4083  * Returns the number of attributes found on success, negative value
4084  * on error. @size is reset to the total size of the data.
4085  * If @size is insufficient to contain the data -E2BIG is returned.
4086  */
security_getselfattr(unsigned int attr,struct lsm_ctx __user * uctx,u32 __user * size,u32 flags)4087 int security_getselfattr(unsigned int attr, struct lsm_ctx __user *uctx,
4088 			 u32 __user *size, u32 flags)
4089 {
4090 	struct lsm_static_call *scall;
4091 	struct lsm_ctx lctx = { .id = LSM_ID_UNDEF, };
4092 	u8 __user *base = (u8 __user *)uctx;
4093 	u32 entrysize;
4094 	u32 total = 0;
4095 	u32 left;
4096 	bool toobig = false;
4097 	bool single = false;
4098 	int count = 0;
4099 	int rc;
4100 
4101 	if (attr == LSM_ATTR_UNDEF)
4102 		return -EINVAL;
4103 	if (size == NULL)
4104 		return -EINVAL;
4105 	if (get_user(left, size))
4106 		return -EFAULT;
4107 
4108 	if (flags) {
4109 		/*
4110 		 * Only flag supported is LSM_FLAG_SINGLE
4111 		 */
4112 		if (flags != LSM_FLAG_SINGLE || !uctx)
4113 			return -EINVAL;
4114 		if (copy_from_user(&lctx, uctx, sizeof(lctx)))
4115 			return -EFAULT;
4116 		/*
4117 		 * If the LSM ID isn't specified it is an error.
4118 		 */
4119 		if (lctx.id == LSM_ID_UNDEF)
4120 			return -EINVAL;
4121 		single = true;
4122 	}
4123 
4124 	/*
4125 	 * In the usual case gather all the data from the LSMs.
4126 	 * In the single case only get the data from the LSM specified.
4127 	 */
4128 	lsm_for_each_hook(scall, getselfattr) {
4129 		if (single && lctx.id != scall->hl->lsmid->id)
4130 			continue;
4131 		entrysize = left;
4132 		if (base)
4133 			uctx = (struct lsm_ctx __user *)(base + total);
4134 		rc = scall->hl->hook.getselfattr(attr, uctx, &entrysize, flags);
4135 		if (rc == -EOPNOTSUPP) {
4136 			rc = 0;
4137 			continue;
4138 		}
4139 		if (rc == -E2BIG) {
4140 			rc = 0;
4141 			left = 0;
4142 			toobig = true;
4143 		} else if (rc < 0)
4144 			return rc;
4145 		else
4146 			left -= entrysize;
4147 
4148 		total += entrysize;
4149 		count += rc;
4150 		if (single)
4151 			break;
4152 	}
4153 	if (put_user(total, size))
4154 		return -EFAULT;
4155 	if (toobig)
4156 		return -E2BIG;
4157 	if (count == 0)
4158 		return LSM_RET_DEFAULT(getselfattr);
4159 	return count;
4160 }
4161 
4162 /*
4163  * Please keep this in sync with it's counterpart in security/lsm_syscalls.c
4164  */
4165 
4166 /**
4167  * security_setselfattr - Set an LSM attribute on the current process.
4168  * @attr: which attribute to set
4169  * @uctx: the user-space source for the information
4170  * @size: the size of the data
4171  * @flags: reserved for future use, must be 0
4172  *
4173  * Set an LSM attribute for the current process. The LSM, attribute
4174  * and new value are included in @uctx.
4175  *
4176  * Returns 0 on success, -EINVAL if the input is inconsistent, -EFAULT
4177  * if the user buffer is inaccessible, E2BIG if size is too big, or an
4178  * LSM specific failure.
4179  */
security_setselfattr(unsigned int attr,struct lsm_ctx __user * uctx,u32 size,u32 flags)4180 int security_setselfattr(unsigned int attr, struct lsm_ctx __user *uctx,
4181 			 u32 size, u32 flags)
4182 {
4183 	struct lsm_static_call *scall;
4184 	struct lsm_ctx *lctx;
4185 	int rc = LSM_RET_DEFAULT(setselfattr);
4186 	u64 required_len;
4187 
4188 	if (flags)
4189 		return -EINVAL;
4190 	if (size < sizeof(*lctx))
4191 		return -EINVAL;
4192 	if (size > PAGE_SIZE)
4193 		return -E2BIG;
4194 
4195 	lctx = memdup_user(uctx, size);
4196 	if (IS_ERR(lctx))
4197 		return PTR_ERR(lctx);
4198 
4199 	if (size < lctx->len ||
4200 	    check_add_overflow(sizeof(*lctx), lctx->ctx_len, &required_len) ||
4201 	    lctx->len < required_len) {
4202 		rc = -EINVAL;
4203 		goto free_out;
4204 	}
4205 
4206 	lsm_for_each_hook(scall, setselfattr)
4207 		if ((scall->hl->lsmid->id) == lctx->id) {
4208 			rc = scall->hl->hook.setselfattr(attr, lctx, size, flags);
4209 			break;
4210 		}
4211 
4212 free_out:
4213 	kfree(lctx);
4214 	return rc;
4215 }
4216 
4217 /**
4218  * security_getprocattr() - Read an attribute for a task
4219  * @p: the task
4220  * @lsmid: LSM identification
4221  * @name: attribute name
4222  * @value: attribute value
4223  *
4224  * Read attribute @name for task @p and store it into @value if allowed.
4225  *
4226  * Return: Returns the length of @value on success, a negative value otherwise.
4227  */
security_getprocattr(struct task_struct * p,int lsmid,const char * name,char ** value)4228 int security_getprocattr(struct task_struct *p, int lsmid, const char *name,
4229 			 char **value)
4230 {
4231 	struct lsm_static_call *scall;
4232 
4233 	lsm_for_each_hook(scall, getprocattr) {
4234 		if (lsmid != 0 && lsmid != scall->hl->lsmid->id)
4235 			continue;
4236 		return scall->hl->hook.getprocattr(p, name, value);
4237 	}
4238 	return LSM_RET_DEFAULT(getprocattr);
4239 }
4240 
4241 /**
4242  * security_setprocattr() - Set an attribute for a task
4243  * @lsmid: LSM identification
4244  * @name: attribute name
4245  * @value: attribute value
4246  * @size: attribute value size
4247  *
4248  * Write (set) the current task's attribute @name to @value, size @size if
4249  * allowed.
4250  *
4251  * Return: Returns bytes written on success, a negative value otherwise.
4252  */
security_setprocattr(int lsmid,const char * name,void * value,size_t size)4253 int security_setprocattr(int lsmid, const char *name, void *value, size_t size)
4254 {
4255 	struct lsm_static_call *scall;
4256 
4257 	lsm_for_each_hook(scall, setprocattr) {
4258 		if (lsmid != 0 && lsmid != scall->hl->lsmid->id)
4259 			continue;
4260 		return scall->hl->hook.setprocattr(name, value, size);
4261 	}
4262 	return LSM_RET_DEFAULT(setprocattr);
4263 }
4264 
4265 /**
4266  * security_netlink_send() - Save info and check if netlink sending is allowed
4267  * @sk: sending socket
4268  * @skb: netlink message
4269  *
4270  * Save security information for a netlink message so that permission checking
4271  * can be performed when the message is processed.  The security information
4272  * can be saved using the eff_cap field of the netlink_skb_parms structure.
4273  * Also may be used to provide fine grained control over message transmission.
4274  *
4275  * Return: Returns 0 if the information was successfully saved and message is
4276  *         allowed to be transmitted.
4277  */
security_netlink_send(struct sock * sk,struct sk_buff * skb)4278 int security_netlink_send(struct sock *sk, struct sk_buff *skb)
4279 {
4280 	return call_int_hook(netlink_send, sk, skb);
4281 }
4282 
4283 /**
4284  * security_ismaclabel() - Check if the named attribute is a MAC label
4285  * @name: full extended attribute name
4286  *
4287  * Check if the extended attribute specified by @name represents a MAC label.
4288  *
4289  * Return: Returns 1 if name is a MAC attribute otherwise returns 0.
4290  */
security_ismaclabel(const char * name)4291 int security_ismaclabel(const char *name)
4292 {
4293 	return call_int_hook(ismaclabel, name);
4294 }
4295 EXPORT_SYMBOL(security_ismaclabel);
4296 
4297 /**
4298  * security_secid_to_secctx() - Convert a secid to a secctx
4299  * @secid: secid
4300  * @secdata: secctx
4301  * @seclen: secctx length
4302  *
4303  * Convert secid to security context.  If @secdata is NULL the length of the
4304  * result will be returned in @seclen, but no @secdata will be returned.  This
4305  * does mean that the length could change between calls to check the length and
4306  * the next call which actually allocates and returns the @secdata.
4307  *
4308  * Return: Return 0 on success, error on failure.
4309  */
security_secid_to_secctx(u32 secid,char ** secdata,u32 * seclen)4310 int security_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
4311 {
4312 	return call_int_hook(secid_to_secctx, secid, secdata, seclen);
4313 }
4314 EXPORT_SYMBOL(security_secid_to_secctx);
4315 
4316 /**
4317  * security_secctx_to_secid() - Convert a secctx to a secid
4318  * @secdata: secctx
4319  * @seclen: length of secctx
4320  * @secid: secid
4321  *
4322  * Convert security context to secid.
4323  *
4324  * Return: Returns 0 on success, error on failure.
4325  */
security_secctx_to_secid(const char * secdata,u32 seclen,u32 * secid)4326 int security_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
4327 {
4328 	*secid = 0;
4329 	return call_int_hook(secctx_to_secid, secdata, seclen, secid);
4330 }
4331 EXPORT_SYMBOL(security_secctx_to_secid);
4332 
4333 /**
4334  * security_release_secctx() - Free a secctx buffer
4335  * @secdata: secctx
4336  * @seclen: length of secctx
4337  *
4338  * Release the security context.
4339  */
security_release_secctx(char * secdata,u32 seclen)4340 void security_release_secctx(char *secdata, u32 seclen)
4341 {
4342 	call_void_hook(release_secctx, secdata, seclen);
4343 }
4344 EXPORT_SYMBOL(security_release_secctx);
4345 
4346 /**
4347  * security_inode_invalidate_secctx() - Invalidate an inode's security label
4348  * @inode: inode
4349  *
4350  * Notify the security module that it must revalidate the security context of
4351  * an inode.
4352  */
security_inode_invalidate_secctx(struct inode * inode)4353 void security_inode_invalidate_secctx(struct inode *inode)
4354 {
4355 	call_void_hook(inode_invalidate_secctx, inode);
4356 }
4357 EXPORT_SYMBOL(security_inode_invalidate_secctx);
4358 
4359 /**
4360  * security_inode_notifysecctx() - Notify the LSM of an inode's security label
4361  * @inode: inode
4362  * @ctx: secctx
4363  * @ctxlen: length of secctx
4364  *
4365  * Notify the security module of what the security context of an inode should
4366  * be.  Initializes the incore security context managed by the security module
4367  * for this inode.  Example usage: NFS client invokes this hook to initialize
4368  * the security context in its incore inode to the value provided by the server
4369  * for the file when the server returned the file's attributes to the client.
4370  * Must be called with inode->i_mutex locked.
4371  *
4372  * Return: Returns 0 on success, error on failure.
4373  */
security_inode_notifysecctx(struct inode * inode,void * ctx,u32 ctxlen)4374 int security_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen)
4375 {
4376 	return call_int_hook(inode_notifysecctx, inode, ctx, ctxlen);
4377 }
4378 EXPORT_SYMBOL(security_inode_notifysecctx);
4379 
4380 /**
4381  * security_inode_setsecctx() - Change the security label of an inode
4382  * @dentry: inode
4383  * @ctx: secctx
4384  * @ctxlen: length of secctx
4385  *
4386  * Change the security context of an inode.  Updates the incore security
4387  * context managed by the security module and invokes the fs code as needed
4388  * (via __vfs_setxattr_noperm) to update any backing xattrs that represent the
4389  * context.  Example usage: NFS server invokes this hook to change the security
4390  * context in its incore inode and on the backing filesystem to a value
4391  * provided by the client on a SETATTR operation.  Must be called with
4392  * inode->i_mutex locked.
4393  *
4394  * Return: Returns 0 on success, error on failure.
4395  */
security_inode_setsecctx(struct dentry * dentry,void * ctx,u32 ctxlen)4396 int security_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen)
4397 {
4398 	return call_int_hook(inode_setsecctx, dentry, ctx, ctxlen);
4399 }
4400 EXPORT_SYMBOL(security_inode_setsecctx);
4401 
4402 /**
4403  * security_inode_getsecctx() - Get the security label of an inode
4404  * @inode: inode
4405  * @ctx: secctx
4406  * @ctxlen: length of secctx
4407  *
4408  * On success, returns 0 and fills out @ctx and @ctxlen with the security
4409  * context for the given @inode.
4410  *
4411  * Return: Returns 0 on success, error on failure.
4412  */
security_inode_getsecctx(struct inode * inode,void ** ctx,u32 * ctxlen)4413 int security_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen)
4414 {
4415 	return call_int_hook(inode_getsecctx, inode, ctx, ctxlen);
4416 }
4417 EXPORT_SYMBOL(security_inode_getsecctx);
4418 
4419 #ifdef CONFIG_WATCH_QUEUE
4420 /**
4421  * security_post_notification() - Check if a watch notification can be posted
4422  * @w_cred: credentials of the task that set the watch
4423  * @cred: credentials of the task which triggered the watch
4424  * @n: the notification
4425  *
4426  * Check to see if a watch notification can be posted to a particular queue.
4427  *
4428  * Return: Returns 0 if permission is granted.
4429  */
security_post_notification(const struct cred * w_cred,const struct cred * cred,struct watch_notification * n)4430 int security_post_notification(const struct cred *w_cred,
4431 			       const struct cred *cred,
4432 			       struct watch_notification *n)
4433 {
4434 	return call_int_hook(post_notification, w_cred, cred, n);
4435 }
4436 #endif /* CONFIG_WATCH_QUEUE */
4437 
4438 #ifdef CONFIG_KEY_NOTIFICATIONS
4439 /**
4440  * security_watch_key() - Check if a task is allowed to watch for key events
4441  * @key: the key to watch
4442  *
4443  * Check to see if a process is allowed to watch for event notifications from
4444  * a key or keyring.
4445  *
4446  * Return: Returns 0 if permission is granted.
4447  */
security_watch_key(struct key * key)4448 int security_watch_key(struct key *key)
4449 {
4450 	return call_int_hook(watch_key, key);
4451 }
4452 #endif /* CONFIG_KEY_NOTIFICATIONS */
4453 
4454 #ifdef CONFIG_SECURITY_NETWORK
4455 /**
4456  * security_unix_stream_connect() - Check if a AF_UNIX stream is allowed
4457  * @sock: originating sock
4458  * @other: peer sock
4459  * @newsk: new sock
4460  *
4461  * Check permissions before establishing a Unix domain stream connection
4462  * between @sock and @other.
4463  *
4464  * The @unix_stream_connect and @unix_may_send hooks were necessary because
4465  * Linux provides an alternative to the conventional file name space for Unix
4466  * domain sockets.  Whereas binding and connecting to sockets in the file name
4467  * space is mediated by the typical file permissions (and caught by the mknod
4468  * and permission hooks in inode_security_ops), binding and connecting to
4469  * sockets in the abstract name space is completely unmediated.  Sufficient
4470  * control of Unix domain sockets in the abstract name space isn't possible
4471  * using only the socket layer hooks, since we need to know the actual target
4472  * socket, which is not looked up until we are inside the af_unix code.
4473  *
4474  * Return: Returns 0 if permission is granted.
4475  */
security_unix_stream_connect(struct sock * sock,struct sock * other,struct sock * newsk)4476 int security_unix_stream_connect(struct sock *sock, struct sock *other,
4477 				 struct sock *newsk)
4478 {
4479 	return call_int_hook(unix_stream_connect, sock, other, newsk);
4480 }
4481 EXPORT_SYMBOL(security_unix_stream_connect);
4482 
4483 /**
4484  * security_unix_may_send() - Check if AF_UNIX socket can send datagrams
4485  * @sock: originating sock
4486  * @other: peer sock
4487  *
4488  * Check permissions before connecting or sending datagrams from @sock to
4489  * @other.
4490  *
4491  * The @unix_stream_connect and @unix_may_send hooks were necessary because
4492  * Linux provides an alternative to the conventional file name space for Unix
4493  * domain sockets.  Whereas binding and connecting to sockets in the file name
4494  * space is mediated by the typical file permissions (and caught by the mknod
4495  * and permission hooks in inode_security_ops), binding and connecting to
4496  * sockets in the abstract name space is completely unmediated.  Sufficient
4497  * control of Unix domain sockets in the abstract name space isn't possible
4498  * using only the socket layer hooks, since we need to know the actual target
4499  * socket, which is not looked up until we are inside the af_unix code.
4500  *
4501  * Return: Returns 0 if permission is granted.
4502  */
security_unix_may_send(struct socket * sock,struct socket * other)4503 int security_unix_may_send(struct socket *sock,  struct socket *other)
4504 {
4505 	return call_int_hook(unix_may_send, sock, other);
4506 }
4507 EXPORT_SYMBOL(security_unix_may_send);
4508 
4509 /**
4510  * security_socket_create() - Check if creating a new socket is allowed
4511  * @family: protocol family
4512  * @type: communications type
4513  * @protocol: requested protocol
4514  * @kern: set to 1 if a kernel socket is requested
4515  *
4516  * Check permissions prior to creating a new socket.
4517  *
4518  * Return: Returns 0 if permission is granted.
4519  */
security_socket_create(int family,int type,int protocol,int kern)4520 int security_socket_create(int family, int type, int protocol, int kern)
4521 {
4522 	return call_int_hook(socket_create, family, type, protocol, kern);
4523 }
4524 
4525 /**
4526  * security_socket_post_create() - Initialize a newly created socket
4527  * @sock: socket
4528  * @family: protocol family
4529  * @type: communications type
4530  * @protocol: requested protocol
4531  * @kern: set to 1 if a kernel socket is requested
4532  *
4533  * This hook allows a module to update or allocate a per-socket security
4534  * structure. Note that the security field was not added directly to the socket
4535  * structure, but rather, the socket security information is stored in the
4536  * associated inode.  Typically, the inode alloc_security hook will allocate
4537  * and attach security information to SOCK_INODE(sock)->i_security.  This hook
4538  * may be used to update the SOCK_INODE(sock)->i_security field with additional
4539  * information that wasn't available when the inode was allocated.
4540  *
4541  * Return: Returns 0 if permission is granted.
4542  */
security_socket_post_create(struct socket * sock,int family,int type,int protocol,int kern)4543 int security_socket_post_create(struct socket *sock, int family,
4544 				int type, int protocol, int kern)
4545 {
4546 	return call_int_hook(socket_post_create, sock, family, type,
4547 			     protocol, kern);
4548 }
4549 
4550 /**
4551  * security_socket_socketpair() - Check if creating a socketpair is allowed
4552  * @socka: first socket
4553  * @sockb: second socket
4554  *
4555  * Check permissions before creating a fresh pair of sockets.
4556  *
4557  * Return: Returns 0 if permission is granted and the connection was
4558  *         established.
4559  */
security_socket_socketpair(struct socket * socka,struct socket * sockb)4560 int security_socket_socketpair(struct socket *socka, struct socket *sockb)
4561 {
4562 	return call_int_hook(socket_socketpair, socka, sockb);
4563 }
4564 EXPORT_SYMBOL(security_socket_socketpair);
4565 
4566 /**
4567  * security_socket_bind() - Check if a socket bind operation is allowed
4568  * @sock: socket
4569  * @address: requested bind address
4570  * @addrlen: length of address
4571  *
4572  * Check permission before socket protocol layer bind operation is performed
4573  * and the socket @sock is bound to the address specified in the @address
4574  * parameter.
4575  *
4576  * Return: Returns 0 if permission is granted.
4577  */
security_socket_bind(struct socket * sock,struct sockaddr * address,int addrlen)4578 int security_socket_bind(struct socket *sock,
4579 			 struct sockaddr *address, int addrlen)
4580 {
4581 	return call_int_hook(socket_bind, sock, address, addrlen);
4582 }
4583 
4584 /**
4585  * security_socket_connect() - Check if a socket connect operation is allowed
4586  * @sock: socket
4587  * @address: address of remote connection point
4588  * @addrlen: length of address
4589  *
4590  * Check permission before socket protocol layer connect operation attempts to
4591  * connect socket @sock to a remote address, @address.
4592  *
4593  * Return: Returns 0 if permission is granted.
4594  */
security_socket_connect(struct socket * sock,struct sockaddr * address,int addrlen)4595 int security_socket_connect(struct socket *sock,
4596 			    struct sockaddr *address, int addrlen)
4597 {
4598 	return call_int_hook(socket_connect, sock, address, addrlen);
4599 }
4600 
4601 /**
4602  * security_socket_listen() - Check if a socket is allowed to listen
4603  * @sock: socket
4604  * @backlog: connection queue size
4605  *
4606  * Check permission before socket protocol layer listen operation.
4607  *
4608  * Return: Returns 0 if permission is granted.
4609  */
security_socket_listen(struct socket * sock,int backlog)4610 int security_socket_listen(struct socket *sock, int backlog)
4611 {
4612 	return call_int_hook(socket_listen, sock, backlog);
4613 }
4614 
4615 /**
4616  * security_socket_accept() - Check if a socket is allowed to accept connections
4617  * @sock: listening socket
4618  * @newsock: newly creation connection socket
4619  *
4620  * Check permission before accepting a new connection.  Note that the new
4621  * socket, @newsock, has been created and some information copied to it, but
4622  * the accept operation has not actually been performed.
4623  *
4624  * Return: Returns 0 if permission is granted.
4625  */
security_socket_accept(struct socket * sock,struct socket * newsock)4626 int security_socket_accept(struct socket *sock, struct socket *newsock)
4627 {
4628 	return call_int_hook(socket_accept, sock, newsock);
4629 }
4630 
4631 /**
4632  * security_socket_sendmsg() - Check if sending a message is allowed
4633  * @sock: sending socket
4634  * @msg: message to send
4635  * @size: size of message
4636  *
4637  * Check permission before transmitting a message to another socket.
4638  *
4639  * Return: Returns 0 if permission is granted.
4640  */
security_socket_sendmsg(struct socket * sock,struct msghdr * msg,int size)4641 int security_socket_sendmsg(struct socket *sock, struct msghdr *msg, int size)
4642 {
4643 	return call_int_hook(socket_sendmsg, sock, msg, size);
4644 }
4645 
4646 /**
4647  * security_socket_recvmsg() - Check if receiving a message is allowed
4648  * @sock: receiving socket
4649  * @msg: message to receive
4650  * @size: size of message
4651  * @flags: operational flags
4652  *
4653  * Check permission before receiving a message from a socket.
4654  *
4655  * Return: Returns 0 if permission is granted.
4656  */
security_socket_recvmsg(struct socket * sock,struct msghdr * msg,int size,int flags)4657 int security_socket_recvmsg(struct socket *sock, struct msghdr *msg,
4658 			    int size, int flags)
4659 {
4660 	return call_int_hook(socket_recvmsg, sock, msg, size, flags);
4661 }
4662 
4663 /**
4664  * security_socket_getsockname() - Check if reading the socket addr is allowed
4665  * @sock: socket
4666  *
4667  * Check permission before reading the local address (name) of the socket
4668  * object.
4669  *
4670  * Return: Returns 0 if permission is granted.
4671  */
security_socket_getsockname(struct socket * sock)4672 int security_socket_getsockname(struct socket *sock)
4673 {
4674 	return call_int_hook(socket_getsockname, sock);
4675 }
4676 
4677 /**
4678  * security_socket_getpeername() - Check if reading the peer's addr is allowed
4679  * @sock: socket
4680  *
4681  * Check permission before the remote address (name) of a socket object.
4682  *
4683  * Return: Returns 0 if permission is granted.
4684  */
security_socket_getpeername(struct socket * sock)4685 int security_socket_getpeername(struct socket *sock)
4686 {
4687 	return call_int_hook(socket_getpeername, sock);
4688 }
4689 
4690 /**
4691  * security_socket_getsockopt() - Check if reading a socket option is allowed
4692  * @sock: socket
4693  * @level: option's protocol level
4694  * @optname: option name
4695  *
4696  * Check permissions before retrieving the options associated with socket
4697  * @sock.
4698  *
4699  * Return: Returns 0 if permission is granted.
4700  */
security_socket_getsockopt(struct socket * sock,int level,int optname)4701 int security_socket_getsockopt(struct socket *sock, int level, int optname)
4702 {
4703 	return call_int_hook(socket_getsockopt, sock, level, optname);
4704 }
4705 
4706 /**
4707  * security_socket_setsockopt() - Check if setting a socket option is allowed
4708  * @sock: socket
4709  * @level: option's protocol level
4710  * @optname: option name
4711  *
4712  * Check permissions before setting the options associated with socket @sock.
4713  *
4714  * Return: Returns 0 if permission is granted.
4715  */
security_socket_setsockopt(struct socket * sock,int level,int optname)4716 int security_socket_setsockopt(struct socket *sock, int level, int optname)
4717 {
4718 	return call_int_hook(socket_setsockopt, sock, level, optname);
4719 }
4720 
4721 /**
4722  * security_socket_shutdown() - Checks if shutting down the socket is allowed
4723  * @sock: socket
4724  * @how: flag indicating how sends and receives are handled
4725  *
4726  * Checks permission before all or part of a connection on the socket @sock is
4727  * shut down.
4728  *
4729  * Return: Returns 0 if permission is granted.
4730  */
security_socket_shutdown(struct socket * sock,int how)4731 int security_socket_shutdown(struct socket *sock, int how)
4732 {
4733 	return call_int_hook(socket_shutdown, sock, how);
4734 }
4735 
4736 /**
4737  * security_sock_rcv_skb() - Check if an incoming network packet is allowed
4738  * @sk: destination sock
4739  * @skb: incoming packet
4740  *
4741  * Check permissions on incoming network packets.  This hook is distinct from
4742  * Netfilter's IP input hooks since it is the first time that the incoming
4743  * sk_buff @skb has been associated with a particular socket, @sk.  Must not
4744  * sleep inside this hook because some callers hold spinlocks.
4745  *
4746  * Return: Returns 0 if permission is granted.
4747  */
security_sock_rcv_skb(struct sock * sk,struct sk_buff * skb)4748 int security_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
4749 {
4750 	return call_int_hook(socket_sock_rcv_skb, sk, skb);
4751 }
4752 EXPORT_SYMBOL(security_sock_rcv_skb);
4753 
4754 /**
4755  * security_socket_getpeersec_stream() - Get the remote peer label
4756  * @sock: socket
4757  * @optval: destination buffer
4758  * @optlen: size of peer label copied into the buffer
4759  * @len: maximum size of the destination buffer
4760  *
4761  * This hook allows the security module to provide peer socket security state
4762  * for unix or connected tcp sockets to userspace via getsockopt SO_GETPEERSEC.
4763  * For tcp sockets this can be meaningful if the socket is associated with an
4764  * ipsec SA.
4765  *
4766  * Return: Returns 0 if all is well, otherwise, typical getsockopt return
4767  *         values.
4768  */
security_socket_getpeersec_stream(struct socket * sock,sockptr_t optval,sockptr_t optlen,unsigned int len)4769 int security_socket_getpeersec_stream(struct socket *sock, sockptr_t optval,
4770 				      sockptr_t optlen, unsigned int len)
4771 {
4772 	return call_int_hook(socket_getpeersec_stream, sock, optval, optlen,
4773 			     len);
4774 }
4775 
4776 /**
4777  * security_socket_getpeersec_dgram() - Get the remote peer label
4778  * @sock: socket
4779  * @skb: datagram packet
4780  * @secid: remote peer label secid
4781  *
4782  * This hook allows the security module to provide peer socket security state
4783  * for udp sockets on a per-packet basis to userspace via getsockopt
4784  * SO_GETPEERSEC. The application must first have indicated the IP_PASSSEC
4785  * option via getsockopt. It can then retrieve the security state returned by
4786  * this hook for a packet via the SCM_SECURITY ancillary message type.
4787  *
4788  * Return: Returns 0 on success, error on failure.
4789  */
security_socket_getpeersec_dgram(struct socket * sock,struct sk_buff * skb,u32 * secid)4790 int security_socket_getpeersec_dgram(struct socket *sock,
4791 				     struct sk_buff *skb, u32 *secid)
4792 {
4793 	return call_int_hook(socket_getpeersec_dgram, sock, skb, secid);
4794 }
4795 EXPORT_SYMBOL(security_socket_getpeersec_dgram);
4796 
4797 /**
4798  * lsm_sock_alloc - allocate a composite sock blob
4799  * @sock: the sock that needs a blob
4800  * @gfp: allocation mode
4801  *
4802  * Allocate the sock blob for all the modules
4803  *
4804  * Returns 0, or -ENOMEM if memory can't be allocated.
4805  */
lsm_sock_alloc(struct sock * sock,gfp_t gfp)4806 static int lsm_sock_alloc(struct sock *sock, gfp_t gfp)
4807 {
4808 	return lsm_blob_alloc(&sock->sk_security, blob_sizes.lbs_sock, gfp);
4809 }
4810 
4811 /**
4812  * security_sk_alloc() - Allocate and initialize a sock's LSM blob
4813  * @sk: sock
4814  * @family: protocol family
4815  * @priority: gfp flags
4816  *
4817  * Allocate and attach a security structure to the sk->sk_security field, which
4818  * is used to copy security attributes between local stream sockets.
4819  *
4820  * Return: Returns 0 on success, error on failure.
4821  */
security_sk_alloc(struct sock * sk,int family,gfp_t priority)4822 int security_sk_alloc(struct sock *sk, int family, gfp_t priority)
4823 {
4824 	int rc = lsm_sock_alloc(sk, priority);
4825 
4826 	if (unlikely(rc))
4827 		return rc;
4828 	rc = call_int_hook(sk_alloc_security, sk, family, priority);
4829 	if (unlikely(rc))
4830 		security_sk_free(sk);
4831 	return rc;
4832 }
4833 
4834 /**
4835  * security_sk_free() - Free the sock's LSM blob
4836  * @sk: sock
4837  *
4838  * Deallocate security structure.
4839  */
security_sk_free(struct sock * sk)4840 void security_sk_free(struct sock *sk)
4841 {
4842 	call_void_hook(sk_free_security, sk);
4843 	kfree(sk->sk_security);
4844 	sk->sk_security = NULL;
4845 }
4846 
4847 /**
4848  * security_sk_clone() - Clone a sock's LSM state
4849  * @sk: original sock
4850  * @newsk: target sock
4851  *
4852  * Clone/copy security structure.
4853  */
security_sk_clone(const struct sock * sk,struct sock * newsk)4854 void security_sk_clone(const struct sock *sk, struct sock *newsk)
4855 {
4856 	call_void_hook(sk_clone_security, sk, newsk);
4857 }
4858 EXPORT_SYMBOL(security_sk_clone);
4859 
4860 /**
4861  * security_sk_classify_flow() - Set a flow's secid based on socket
4862  * @sk: original socket
4863  * @flic: target flow
4864  *
4865  * Set the target flow's secid to socket's secid.
4866  */
security_sk_classify_flow(const struct sock * sk,struct flowi_common * flic)4867 void security_sk_classify_flow(const struct sock *sk, struct flowi_common *flic)
4868 {
4869 	call_void_hook(sk_getsecid, sk, &flic->flowic_secid);
4870 }
4871 EXPORT_SYMBOL(security_sk_classify_flow);
4872 
4873 /**
4874  * security_req_classify_flow() - Set a flow's secid based on request_sock
4875  * @req: request_sock
4876  * @flic: target flow
4877  *
4878  * Sets @flic's secid to @req's secid.
4879  */
security_req_classify_flow(const struct request_sock * req,struct flowi_common * flic)4880 void security_req_classify_flow(const struct request_sock *req,
4881 				struct flowi_common *flic)
4882 {
4883 	call_void_hook(req_classify_flow, req, flic);
4884 }
4885 EXPORT_SYMBOL(security_req_classify_flow);
4886 
4887 /**
4888  * security_sock_graft() - Reconcile LSM state when grafting a sock on a socket
4889  * @sk: sock being grafted
4890  * @parent: target parent socket
4891  *
4892  * Sets @parent's inode secid to @sk's secid and update @sk with any necessary
4893  * LSM state from @parent.
4894  */
security_sock_graft(struct sock * sk,struct socket * parent)4895 void security_sock_graft(struct sock *sk, struct socket *parent)
4896 {
4897 	call_void_hook(sock_graft, sk, parent);
4898 }
4899 EXPORT_SYMBOL(security_sock_graft);
4900 
4901 /**
4902  * security_inet_conn_request() - Set request_sock state using incoming connect
4903  * @sk: parent listening sock
4904  * @skb: incoming connection
4905  * @req: new request_sock
4906  *
4907  * Initialize the @req LSM state based on @sk and the incoming connect in @skb.
4908  *
4909  * Return: Returns 0 if permission is granted.
4910  */
security_inet_conn_request(const struct sock * sk,struct sk_buff * skb,struct request_sock * req)4911 int security_inet_conn_request(const struct sock *sk,
4912 			       struct sk_buff *skb, struct request_sock *req)
4913 {
4914 	return call_int_hook(inet_conn_request, sk, skb, req);
4915 }
4916 EXPORT_SYMBOL(security_inet_conn_request);
4917 
4918 /**
4919  * security_inet_csk_clone() - Set new sock LSM state based on request_sock
4920  * @newsk: new sock
4921  * @req: connection request_sock
4922  *
4923  * Set that LSM state of @sock using the LSM state from @req.
4924  */
security_inet_csk_clone(struct sock * newsk,const struct request_sock * req)4925 void security_inet_csk_clone(struct sock *newsk,
4926 			     const struct request_sock *req)
4927 {
4928 	call_void_hook(inet_csk_clone, newsk, req);
4929 }
4930 
4931 /**
4932  * security_inet_conn_established() - Update sock's LSM state with connection
4933  * @sk: sock
4934  * @skb: connection packet
4935  *
4936  * Update @sock's LSM state to represent a new connection from @skb.
4937  */
security_inet_conn_established(struct sock * sk,struct sk_buff * skb)4938 void security_inet_conn_established(struct sock *sk,
4939 				    struct sk_buff *skb)
4940 {
4941 	call_void_hook(inet_conn_established, sk, skb);
4942 }
4943 EXPORT_SYMBOL(security_inet_conn_established);
4944 
4945 /**
4946  * security_secmark_relabel_packet() - Check if setting a secmark is allowed
4947  * @secid: new secmark value
4948  *
4949  * Check if the process should be allowed to relabel packets to @secid.
4950  *
4951  * Return: Returns 0 if permission is granted.
4952  */
security_secmark_relabel_packet(u32 secid)4953 int security_secmark_relabel_packet(u32 secid)
4954 {
4955 	return call_int_hook(secmark_relabel_packet, secid);
4956 }
4957 EXPORT_SYMBOL(security_secmark_relabel_packet);
4958 
4959 /**
4960  * security_secmark_refcount_inc() - Increment the secmark labeling rule count
4961  *
4962  * Tells the LSM to increment the number of secmark labeling rules loaded.
4963  */
security_secmark_refcount_inc(void)4964 void security_secmark_refcount_inc(void)
4965 {
4966 	call_void_hook(secmark_refcount_inc);
4967 }
4968 EXPORT_SYMBOL(security_secmark_refcount_inc);
4969 
4970 /**
4971  * security_secmark_refcount_dec() - Decrement the secmark labeling rule count
4972  *
4973  * Tells the LSM to decrement the number of secmark labeling rules loaded.
4974  */
security_secmark_refcount_dec(void)4975 void security_secmark_refcount_dec(void)
4976 {
4977 	call_void_hook(secmark_refcount_dec);
4978 }
4979 EXPORT_SYMBOL(security_secmark_refcount_dec);
4980 
4981 /**
4982  * security_tun_dev_alloc_security() - Allocate a LSM blob for a TUN device
4983  * @security: pointer to the LSM blob
4984  *
4985  * This hook allows a module to allocate a security structure for a TUN	device,
4986  * returning the pointer in @security.
4987  *
4988  * Return: Returns a zero on success, negative values on failure.
4989  */
security_tun_dev_alloc_security(void ** security)4990 int security_tun_dev_alloc_security(void **security)
4991 {
4992 	int rc;
4993 
4994 	rc = lsm_blob_alloc(security, blob_sizes.lbs_tun_dev, GFP_KERNEL);
4995 	if (rc)
4996 		return rc;
4997 
4998 	rc = call_int_hook(tun_dev_alloc_security, *security);
4999 	if (rc) {
5000 		kfree(*security);
5001 		*security = NULL;
5002 	}
5003 	return rc;
5004 }
5005 EXPORT_SYMBOL(security_tun_dev_alloc_security);
5006 
5007 /**
5008  * security_tun_dev_free_security() - Free a TUN device LSM blob
5009  * @security: LSM blob
5010  *
5011  * This hook allows a module to free the security structure for a TUN device.
5012  */
security_tun_dev_free_security(void * security)5013 void security_tun_dev_free_security(void *security)
5014 {
5015 	kfree(security);
5016 }
5017 EXPORT_SYMBOL(security_tun_dev_free_security);
5018 
5019 /**
5020  * security_tun_dev_create() - Check if creating a TUN device is allowed
5021  *
5022  * Check permissions prior to creating a new TUN device.
5023  *
5024  * Return: Returns 0 if permission is granted.
5025  */
security_tun_dev_create(void)5026 int security_tun_dev_create(void)
5027 {
5028 	return call_int_hook(tun_dev_create);
5029 }
5030 EXPORT_SYMBOL(security_tun_dev_create);
5031 
5032 /**
5033  * security_tun_dev_attach_queue() - Check if attaching a TUN queue is allowed
5034  * @security: TUN device LSM blob
5035  *
5036  * Check permissions prior to attaching to a TUN device queue.
5037  *
5038  * Return: Returns 0 if permission is granted.
5039  */
security_tun_dev_attach_queue(void * security)5040 int security_tun_dev_attach_queue(void *security)
5041 {
5042 	return call_int_hook(tun_dev_attach_queue, security);
5043 }
5044 EXPORT_SYMBOL(security_tun_dev_attach_queue);
5045 
5046 /**
5047  * security_tun_dev_attach() - Update TUN device LSM state on attach
5048  * @sk: associated sock
5049  * @security: TUN device LSM blob
5050  *
5051  * This hook can be used by the module to update any security state associated
5052  * with the TUN device's sock structure.
5053  *
5054  * Return: Returns 0 if permission is granted.
5055  */
security_tun_dev_attach(struct sock * sk,void * security)5056 int security_tun_dev_attach(struct sock *sk, void *security)
5057 {
5058 	return call_int_hook(tun_dev_attach, sk, security);
5059 }
5060 EXPORT_SYMBOL(security_tun_dev_attach);
5061 
5062 /**
5063  * security_tun_dev_open() - Update TUN device LSM state on open
5064  * @security: TUN device LSM blob
5065  *
5066  * This hook can be used by the module to update any security state associated
5067  * with the TUN device's security structure.
5068  *
5069  * Return: Returns 0 if permission is granted.
5070  */
security_tun_dev_open(void * security)5071 int security_tun_dev_open(void *security)
5072 {
5073 	return call_int_hook(tun_dev_open, security);
5074 }
5075 EXPORT_SYMBOL(security_tun_dev_open);
5076 
5077 /**
5078  * security_sctp_assoc_request() - Update the LSM on a SCTP association req
5079  * @asoc: SCTP association
5080  * @skb: packet requesting the association
5081  *
5082  * Passes the @asoc and @chunk->skb of the association INIT packet to the LSM.
5083  *
5084  * Return: Returns 0 on success, error on failure.
5085  */
security_sctp_assoc_request(struct sctp_association * asoc,struct sk_buff * skb)5086 int security_sctp_assoc_request(struct sctp_association *asoc,
5087 				struct sk_buff *skb)
5088 {
5089 	return call_int_hook(sctp_assoc_request, asoc, skb);
5090 }
5091 EXPORT_SYMBOL(security_sctp_assoc_request);
5092 
5093 /**
5094  * security_sctp_bind_connect() - Validate a list of addrs for a SCTP option
5095  * @sk: socket
5096  * @optname: SCTP option to validate
5097  * @address: list of IP addresses to validate
5098  * @addrlen: length of the address list
5099  *
5100  * Validiate permissions required for each address associated with sock	@sk.
5101  * Depending on @optname, the addresses will be treated as either a connect or
5102  * bind service. The @addrlen is calculated on each IPv4 and IPv6 address using
5103  * sizeof(struct sockaddr_in) or sizeof(struct sockaddr_in6).
5104  *
5105  * Return: Returns 0 on success, error on failure.
5106  */
security_sctp_bind_connect(struct sock * sk,int optname,struct sockaddr * address,int addrlen)5107 int security_sctp_bind_connect(struct sock *sk, int optname,
5108 			       struct sockaddr *address, int addrlen)
5109 {
5110 	return call_int_hook(sctp_bind_connect, sk, optname, address, addrlen);
5111 }
5112 EXPORT_SYMBOL(security_sctp_bind_connect);
5113 
5114 /**
5115  * security_sctp_sk_clone() - Clone a SCTP sock's LSM state
5116  * @asoc: SCTP association
5117  * @sk: original sock
5118  * @newsk: target sock
5119  *
5120  * Called whenever a new socket is created by accept(2) (i.e. a TCP style
5121  * socket) or when a socket is 'peeled off' e.g userspace calls
5122  * sctp_peeloff(3).
5123  */
security_sctp_sk_clone(struct sctp_association * asoc,struct sock * sk,struct sock * newsk)5124 void security_sctp_sk_clone(struct sctp_association *asoc, struct sock *sk,
5125 			    struct sock *newsk)
5126 {
5127 	call_void_hook(sctp_sk_clone, asoc, sk, newsk);
5128 }
5129 EXPORT_SYMBOL(security_sctp_sk_clone);
5130 
5131 /**
5132  * security_sctp_assoc_established() - Update LSM state when assoc established
5133  * @asoc: SCTP association
5134  * @skb: packet establishing the association
5135  *
5136  * Passes the @asoc and @chunk->skb of the association COOKIE_ACK packet to the
5137  * security module.
5138  *
5139  * Return: Returns 0 if permission is granted.
5140  */
security_sctp_assoc_established(struct sctp_association * asoc,struct sk_buff * skb)5141 int security_sctp_assoc_established(struct sctp_association *asoc,
5142 				    struct sk_buff *skb)
5143 {
5144 	return call_int_hook(sctp_assoc_established, asoc, skb);
5145 }
5146 EXPORT_SYMBOL(security_sctp_assoc_established);
5147 
5148 /**
5149  * security_mptcp_add_subflow() - Inherit the LSM label from the MPTCP socket
5150  * @sk: the owning MPTCP socket
5151  * @ssk: the new subflow
5152  *
5153  * Update the labeling for the given MPTCP subflow, to match the one of the
5154  * owning MPTCP socket. This hook has to be called after the socket creation and
5155  * initialization via the security_socket_create() and
5156  * security_socket_post_create() LSM hooks.
5157  *
5158  * Return: Returns 0 on success or a negative error code on failure.
5159  */
security_mptcp_add_subflow(struct sock * sk,struct sock * ssk)5160 int security_mptcp_add_subflow(struct sock *sk, struct sock *ssk)
5161 {
5162 	return call_int_hook(mptcp_add_subflow, sk, ssk);
5163 }
5164 
5165 #endif	/* CONFIG_SECURITY_NETWORK */
5166 
5167 #ifdef CONFIG_SECURITY_INFINIBAND
5168 /**
5169  * security_ib_pkey_access() - Check if access to an IB pkey is allowed
5170  * @sec: LSM blob
5171  * @subnet_prefix: subnet prefix of the port
5172  * @pkey: IB pkey
5173  *
5174  * Check permission to access a pkey when modifying a QP.
5175  *
5176  * Return: Returns 0 if permission is granted.
5177  */
security_ib_pkey_access(void * sec,u64 subnet_prefix,u16 pkey)5178 int security_ib_pkey_access(void *sec, u64 subnet_prefix, u16 pkey)
5179 {
5180 	return call_int_hook(ib_pkey_access, sec, subnet_prefix, pkey);
5181 }
5182 EXPORT_SYMBOL(security_ib_pkey_access);
5183 
5184 /**
5185  * security_ib_endport_manage_subnet() - Check if SMPs traffic is allowed
5186  * @sec: LSM blob
5187  * @dev_name: IB device name
5188  * @port_num: port number
5189  *
5190  * Check permissions to send and receive SMPs on a end port.
5191  *
5192  * Return: Returns 0 if permission is granted.
5193  */
security_ib_endport_manage_subnet(void * sec,const char * dev_name,u8 port_num)5194 int security_ib_endport_manage_subnet(void *sec,
5195 				      const char *dev_name, u8 port_num)
5196 {
5197 	return call_int_hook(ib_endport_manage_subnet, sec, dev_name, port_num);
5198 }
5199 EXPORT_SYMBOL(security_ib_endport_manage_subnet);
5200 
5201 /**
5202  * security_ib_alloc_security() - Allocate an Infiniband LSM blob
5203  * @sec: LSM blob
5204  *
5205  * Allocate a security structure for Infiniband objects.
5206  *
5207  * Return: Returns 0 on success, non-zero on failure.
5208  */
security_ib_alloc_security(void ** sec)5209 int security_ib_alloc_security(void **sec)
5210 {
5211 	int rc;
5212 
5213 	rc = lsm_blob_alloc(sec, blob_sizes.lbs_ib, GFP_KERNEL);
5214 	if (rc)
5215 		return rc;
5216 
5217 	rc = call_int_hook(ib_alloc_security, *sec);
5218 	if (rc) {
5219 		kfree(*sec);
5220 		*sec = NULL;
5221 	}
5222 	return rc;
5223 }
5224 EXPORT_SYMBOL(security_ib_alloc_security);
5225 
5226 /**
5227  * security_ib_free_security() - Free an Infiniband LSM blob
5228  * @sec: LSM blob
5229  *
5230  * Deallocate an Infiniband security structure.
5231  */
security_ib_free_security(void * sec)5232 void security_ib_free_security(void *sec)
5233 {
5234 	kfree(sec);
5235 }
5236 EXPORT_SYMBOL(security_ib_free_security);
5237 #endif	/* CONFIG_SECURITY_INFINIBAND */
5238 
5239 #ifdef CONFIG_SECURITY_NETWORK_XFRM
5240 /**
5241  * security_xfrm_policy_alloc() - Allocate a xfrm policy LSM blob
5242  * @ctxp: xfrm security context being added to the SPD
5243  * @sec_ctx: security label provided by userspace
5244  * @gfp: gfp flags
5245  *
5246  * Allocate a security structure to the xp->security field; the security field
5247  * is initialized to NULL when the xfrm_policy is allocated.
5248  *
5249  * Return:  Return 0 if operation was successful.
5250  */
security_xfrm_policy_alloc(struct xfrm_sec_ctx ** ctxp,struct xfrm_user_sec_ctx * sec_ctx,gfp_t gfp)5251 int security_xfrm_policy_alloc(struct xfrm_sec_ctx **ctxp,
5252 			       struct xfrm_user_sec_ctx *sec_ctx,
5253 			       gfp_t gfp)
5254 {
5255 	return call_int_hook(xfrm_policy_alloc_security, ctxp, sec_ctx, gfp);
5256 }
5257 EXPORT_SYMBOL(security_xfrm_policy_alloc);
5258 
5259 /**
5260  * security_xfrm_policy_clone() - Clone xfrm policy LSM state
5261  * @old_ctx: xfrm security context
5262  * @new_ctxp: target xfrm security context
5263  *
5264  * Allocate a security structure in new_ctxp that contains the information from
5265  * the old_ctx structure.
5266  *
5267  * Return: Return 0 if operation was successful.
5268  */
security_xfrm_policy_clone(struct xfrm_sec_ctx * old_ctx,struct xfrm_sec_ctx ** new_ctxp)5269 int security_xfrm_policy_clone(struct xfrm_sec_ctx *old_ctx,
5270 			       struct xfrm_sec_ctx **new_ctxp)
5271 {
5272 	return call_int_hook(xfrm_policy_clone_security, old_ctx, new_ctxp);
5273 }
5274 
5275 /**
5276  * security_xfrm_policy_free() - Free a xfrm security context
5277  * @ctx: xfrm security context
5278  *
5279  * Free LSM resources associated with @ctx.
5280  */
security_xfrm_policy_free(struct xfrm_sec_ctx * ctx)5281 void security_xfrm_policy_free(struct xfrm_sec_ctx *ctx)
5282 {
5283 	call_void_hook(xfrm_policy_free_security, ctx);
5284 }
5285 EXPORT_SYMBOL(security_xfrm_policy_free);
5286 
5287 /**
5288  * security_xfrm_policy_delete() - Check if deleting a xfrm policy is allowed
5289  * @ctx: xfrm security context
5290  *
5291  * Authorize deletion of a SPD entry.
5292  *
5293  * Return: Returns 0 if permission is granted.
5294  */
security_xfrm_policy_delete(struct xfrm_sec_ctx * ctx)5295 int security_xfrm_policy_delete(struct xfrm_sec_ctx *ctx)
5296 {
5297 	return call_int_hook(xfrm_policy_delete_security, ctx);
5298 }
5299 
5300 /**
5301  * security_xfrm_state_alloc() - Allocate a xfrm state LSM blob
5302  * @x: xfrm state being added to the SAD
5303  * @sec_ctx: security label provided by userspace
5304  *
5305  * Allocate a security structure to the @x->security field; the security field
5306  * is initialized to NULL when the xfrm_state is allocated. Set the context to
5307  * correspond to @sec_ctx.
5308  *
5309  * Return: Return 0 if operation was successful.
5310  */
security_xfrm_state_alloc(struct xfrm_state * x,struct xfrm_user_sec_ctx * sec_ctx)5311 int security_xfrm_state_alloc(struct xfrm_state *x,
5312 			      struct xfrm_user_sec_ctx *sec_ctx)
5313 {
5314 	return call_int_hook(xfrm_state_alloc, x, sec_ctx);
5315 }
5316 EXPORT_SYMBOL(security_xfrm_state_alloc);
5317 
5318 /**
5319  * security_xfrm_state_alloc_acquire() - Allocate a xfrm state LSM blob
5320  * @x: xfrm state being added to the SAD
5321  * @polsec: associated policy's security context
5322  * @secid: secid from the flow
5323  *
5324  * Allocate a security structure to the x->security field; the security field
5325  * is initialized to NULL when the xfrm_state is allocated.  Set the context to
5326  * correspond to secid.
5327  *
5328  * Return: Returns 0 if operation was successful.
5329  */
security_xfrm_state_alloc_acquire(struct xfrm_state * x,struct xfrm_sec_ctx * polsec,u32 secid)5330 int security_xfrm_state_alloc_acquire(struct xfrm_state *x,
5331 				      struct xfrm_sec_ctx *polsec, u32 secid)
5332 {
5333 	return call_int_hook(xfrm_state_alloc_acquire, x, polsec, secid);
5334 }
5335 
5336 /**
5337  * security_xfrm_state_delete() - Check if deleting a xfrm state is allowed
5338  * @x: xfrm state
5339  *
5340  * Authorize deletion of x->security.
5341  *
5342  * Return: Returns 0 if permission is granted.
5343  */
security_xfrm_state_delete(struct xfrm_state * x)5344 int security_xfrm_state_delete(struct xfrm_state *x)
5345 {
5346 	return call_int_hook(xfrm_state_delete_security, x);
5347 }
5348 EXPORT_SYMBOL(security_xfrm_state_delete);
5349 
5350 /**
5351  * security_xfrm_state_free() - Free a xfrm state
5352  * @x: xfrm state
5353  *
5354  * Deallocate x->security.
5355  */
security_xfrm_state_free(struct xfrm_state * x)5356 void security_xfrm_state_free(struct xfrm_state *x)
5357 {
5358 	call_void_hook(xfrm_state_free_security, x);
5359 }
5360 
5361 /**
5362  * security_xfrm_policy_lookup() - Check if using a xfrm policy is allowed
5363  * @ctx: target xfrm security context
5364  * @fl_secid: flow secid used to authorize access
5365  *
5366  * Check permission when a flow selects a xfrm_policy for processing XFRMs on a
5367  * packet.  The hook is called when selecting either a per-socket policy or a
5368  * generic xfrm policy.
5369  *
5370  * Return: Return 0 if permission is granted, -ESRCH otherwise, or -errno on
5371  *         other errors.
5372  */
security_xfrm_policy_lookup(struct xfrm_sec_ctx * ctx,u32 fl_secid)5373 int security_xfrm_policy_lookup(struct xfrm_sec_ctx *ctx, u32 fl_secid)
5374 {
5375 	return call_int_hook(xfrm_policy_lookup, ctx, fl_secid);
5376 }
5377 
5378 /**
5379  * security_xfrm_state_pol_flow_match() - Check for a xfrm match
5380  * @x: xfrm state to match
5381  * @xp: xfrm policy to check for a match
5382  * @flic: flow to check for a match.
5383  *
5384  * Check @xp and @flic for a match with @x.
5385  *
5386  * Return: Returns 1 if there is a match.
5387  */
security_xfrm_state_pol_flow_match(struct xfrm_state * x,struct xfrm_policy * xp,const struct flowi_common * flic)5388 int security_xfrm_state_pol_flow_match(struct xfrm_state *x,
5389 				       struct xfrm_policy *xp,
5390 				       const struct flowi_common *flic)
5391 {
5392 	struct lsm_static_call *scall;
5393 	int rc = LSM_RET_DEFAULT(xfrm_state_pol_flow_match);
5394 
5395 	/*
5396 	 * Since this function is expected to return 0 or 1, the judgment
5397 	 * becomes difficult if multiple LSMs supply this call. Fortunately,
5398 	 * we can use the first LSM's judgment because currently only SELinux
5399 	 * supplies this call.
5400 	 *
5401 	 * For speed optimization, we explicitly break the loop rather than
5402 	 * using the macro
5403 	 */
5404 	lsm_for_each_hook(scall, xfrm_state_pol_flow_match) {
5405 		rc = scall->hl->hook.xfrm_state_pol_flow_match(x, xp, flic);
5406 		break;
5407 	}
5408 	return rc;
5409 }
5410 
5411 /**
5412  * security_xfrm_decode_session() - Determine the xfrm secid for a packet
5413  * @skb: xfrm packet
5414  * @secid: secid
5415  *
5416  * Decode the packet in @skb and return the security label in @secid.
5417  *
5418  * Return: Return 0 if all xfrms used have the same secid.
5419  */
security_xfrm_decode_session(struct sk_buff * skb,u32 * secid)5420 int security_xfrm_decode_session(struct sk_buff *skb, u32 *secid)
5421 {
5422 	return call_int_hook(xfrm_decode_session, skb, secid, 1);
5423 }
5424 
security_skb_classify_flow(struct sk_buff * skb,struct flowi_common * flic)5425 void security_skb_classify_flow(struct sk_buff *skb, struct flowi_common *flic)
5426 {
5427 	int rc = call_int_hook(xfrm_decode_session, skb, &flic->flowic_secid,
5428 			       0);
5429 
5430 	BUG_ON(rc);
5431 }
5432 EXPORT_SYMBOL(security_skb_classify_flow);
5433 #endif	/* CONFIG_SECURITY_NETWORK_XFRM */
5434 
5435 #ifdef CONFIG_KEYS
5436 /**
5437  * security_key_alloc() - Allocate and initialize a kernel key LSM blob
5438  * @key: key
5439  * @cred: credentials
5440  * @flags: allocation flags
5441  *
5442  * Permit allocation of a key and assign security data. Note that key does not
5443  * have a serial number assigned at this point.
5444  *
5445  * Return: Return 0 if permission is granted, -ve error otherwise.
5446  */
security_key_alloc(struct key * key,const struct cred * cred,unsigned long flags)5447 int security_key_alloc(struct key *key, const struct cred *cred,
5448 		       unsigned long flags)
5449 {
5450 	int rc = lsm_key_alloc(key);
5451 
5452 	if (unlikely(rc))
5453 		return rc;
5454 	rc = call_int_hook(key_alloc, key, cred, flags);
5455 	if (unlikely(rc))
5456 		security_key_free(key);
5457 	return rc;
5458 }
5459 
5460 /**
5461  * security_key_free() - Free a kernel key LSM blob
5462  * @key: key
5463  *
5464  * Notification of destruction; free security data.
5465  */
security_key_free(struct key * key)5466 void security_key_free(struct key *key)
5467 {
5468 	kfree(key->security);
5469 	key->security = NULL;
5470 }
5471 
5472 /**
5473  * security_key_permission() - Check if a kernel key operation is allowed
5474  * @key_ref: key reference
5475  * @cred: credentials of actor requesting access
5476  * @need_perm: requested permissions
5477  *
5478  * See whether a specific operational right is granted to a process on a key.
5479  *
5480  * Return: Return 0 if permission is granted, -ve error otherwise.
5481  */
security_key_permission(key_ref_t key_ref,const struct cred * cred,enum key_need_perm need_perm)5482 int security_key_permission(key_ref_t key_ref, const struct cred *cred,
5483 			    enum key_need_perm need_perm)
5484 {
5485 	return call_int_hook(key_permission, key_ref, cred, need_perm);
5486 }
5487 
5488 /**
5489  * security_key_getsecurity() - Get the key's security label
5490  * @key: key
5491  * @buffer: security label buffer
5492  *
5493  * Get a textual representation of the security context attached to a key for
5494  * the purposes of honouring KEYCTL_GETSECURITY.  This function allocates the
5495  * storage for the NUL-terminated string and the caller should free it.
5496  *
5497  * Return: Returns the length of @buffer (including terminating NUL) or -ve if
5498  *         an error occurs.  May also return 0 (and a NULL buffer pointer) if
5499  *         there is no security label assigned to the key.
5500  */
security_key_getsecurity(struct key * key,char ** buffer)5501 int security_key_getsecurity(struct key *key, char **buffer)
5502 {
5503 	*buffer = NULL;
5504 	return call_int_hook(key_getsecurity, key, buffer);
5505 }
5506 
5507 /**
5508  * security_key_post_create_or_update() - Notification of key create or update
5509  * @keyring: keyring to which the key is linked to
5510  * @key: created or updated key
5511  * @payload: data used to instantiate or update the key
5512  * @payload_len: length of payload
5513  * @flags: key flags
5514  * @create: flag indicating whether the key was created or updated
5515  *
5516  * Notify the caller of a key creation or update.
5517  */
security_key_post_create_or_update(struct key * keyring,struct key * key,const void * payload,size_t payload_len,unsigned long flags,bool create)5518 void security_key_post_create_or_update(struct key *keyring, struct key *key,
5519 					const void *payload, size_t payload_len,
5520 					unsigned long flags, bool create)
5521 {
5522 	call_void_hook(key_post_create_or_update, keyring, key, payload,
5523 		       payload_len, flags, create);
5524 }
5525 #endif	/* CONFIG_KEYS */
5526 
5527 #ifdef CONFIG_AUDIT
5528 /**
5529  * security_audit_rule_init() - Allocate and init an LSM audit rule struct
5530  * @field: audit action
5531  * @op: rule operator
5532  * @rulestr: rule context
5533  * @lsmrule: receive buffer for audit rule struct
5534  * @gfp: GFP flag used for kmalloc
5535  *
5536  * Allocate and initialize an LSM audit rule structure.
5537  *
5538  * Return: Return 0 if @lsmrule has been successfully set, -EINVAL in case of
5539  *         an invalid rule.
5540  */
security_audit_rule_init(u32 field,u32 op,char * rulestr,void ** lsmrule,gfp_t gfp)5541 int security_audit_rule_init(u32 field, u32 op, char *rulestr, void **lsmrule,
5542 			     gfp_t gfp)
5543 {
5544 	return call_int_hook(audit_rule_init, field, op, rulestr, lsmrule, gfp);
5545 }
5546 
5547 /**
5548  * security_audit_rule_known() - Check if an audit rule contains LSM fields
5549  * @krule: audit rule
5550  *
5551  * Specifies whether given @krule contains any fields related to the current
5552  * LSM.
5553  *
5554  * Return: Returns 1 in case of relation found, 0 otherwise.
5555  */
security_audit_rule_known(struct audit_krule * krule)5556 int security_audit_rule_known(struct audit_krule *krule)
5557 {
5558 	return call_int_hook(audit_rule_known, krule);
5559 }
5560 
5561 /**
5562  * security_audit_rule_free() - Free an LSM audit rule struct
5563  * @lsmrule: audit rule struct
5564  *
5565  * Deallocate the LSM audit rule structure previously allocated by
5566  * audit_rule_init().
5567  */
security_audit_rule_free(void * lsmrule)5568 void security_audit_rule_free(void *lsmrule)
5569 {
5570 	call_void_hook(audit_rule_free, lsmrule);
5571 }
5572 
5573 /**
5574  * security_audit_rule_match() - Check if a label matches an audit rule
5575  * @secid: security label
5576  * @field: LSM audit field
5577  * @op: matching operator
5578  * @lsmrule: audit rule
5579  *
5580  * Determine if given @secid matches a rule previously approved by
5581  * security_audit_rule_known().
5582  *
5583  * Return: Returns 1 if secid matches the rule, 0 if it does not, -ERRNO on
5584  *         failure.
5585  */
security_audit_rule_match(u32 secid,u32 field,u32 op,void * lsmrule)5586 int security_audit_rule_match(u32 secid, u32 field, u32 op, void *lsmrule)
5587 {
5588 	return call_int_hook(audit_rule_match, secid, field, op, lsmrule);
5589 }
5590 #endif /* CONFIG_AUDIT */
5591 
5592 #ifdef CONFIG_BPF_SYSCALL
5593 /**
5594  * security_bpf() - Check if the bpf syscall operation is allowed
5595  * @cmd: command
5596  * @attr: bpf attribute
5597  * @size: size
5598  *
5599  * Do a initial check for all bpf syscalls after the attribute is copied into
5600  * the kernel. The actual security module can implement their own rules to
5601  * check the specific cmd they need.
5602  *
5603  * Return: Returns 0 if permission is granted.
5604  */
security_bpf(int cmd,union bpf_attr * attr,unsigned int size)5605 int security_bpf(int cmd, union bpf_attr *attr, unsigned int size)
5606 {
5607 	return call_int_hook(bpf, cmd, attr, size);
5608 }
5609 
5610 /**
5611  * security_bpf_map() - Check if access to a bpf map is allowed
5612  * @map: bpf map
5613  * @fmode: mode
5614  *
5615  * Do a check when the kernel generates and returns a file descriptor for eBPF
5616  * maps.
5617  *
5618  * Return: Returns 0 if permission is granted.
5619  */
security_bpf_map(struct bpf_map * map,fmode_t fmode)5620 int security_bpf_map(struct bpf_map *map, fmode_t fmode)
5621 {
5622 	return call_int_hook(bpf_map, map, fmode);
5623 }
5624 
5625 /**
5626  * security_bpf_prog() - Check if access to a bpf program is allowed
5627  * @prog: bpf program
5628  *
5629  * Do a check when the kernel generates and returns a file descriptor for eBPF
5630  * programs.
5631  *
5632  * Return: Returns 0 if permission is granted.
5633  */
security_bpf_prog(struct bpf_prog * prog)5634 int security_bpf_prog(struct bpf_prog *prog)
5635 {
5636 	return call_int_hook(bpf_prog, prog);
5637 }
5638 
5639 /**
5640  * security_bpf_map_create() - Check if BPF map creation is allowed
5641  * @map: BPF map object
5642  * @attr: BPF syscall attributes used to create BPF map
5643  * @token: BPF token used to grant user access
5644  *
5645  * Do a check when the kernel creates a new BPF map. This is also the
5646  * point where LSM blob is allocated for LSMs that need them.
5647  *
5648  * Return: Returns 0 on success, error on failure.
5649  */
security_bpf_map_create(struct bpf_map * map,union bpf_attr * attr,struct bpf_token * token)5650 int security_bpf_map_create(struct bpf_map *map, union bpf_attr *attr,
5651 			    struct bpf_token *token)
5652 {
5653 	return call_int_hook(bpf_map_create, map, attr, token);
5654 }
5655 
5656 /**
5657  * security_bpf_prog_load() - Check if loading of BPF program is allowed
5658  * @prog: BPF program object
5659  * @attr: BPF syscall attributes used to create BPF program
5660  * @token: BPF token used to grant user access to BPF subsystem
5661  *
5662  * Perform an access control check when the kernel loads a BPF program and
5663  * allocates associated BPF program object. This hook is also responsible for
5664  * allocating any required LSM state for the BPF program.
5665  *
5666  * Return: Returns 0 on success, error on failure.
5667  */
security_bpf_prog_load(struct bpf_prog * prog,union bpf_attr * attr,struct bpf_token * token)5668 int security_bpf_prog_load(struct bpf_prog *prog, union bpf_attr *attr,
5669 			   struct bpf_token *token)
5670 {
5671 	return call_int_hook(bpf_prog_load, prog, attr, token);
5672 }
5673 
5674 /**
5675  * security_bpf_token_create() - Check if creating of BPF token is allowed
5676  * @token: BPF token object
5677  * @attr: BPF syscall attributes used to create BPF token
5678  * @path: path pointing to BPF FS mount point from which BPF token is created
5679  *
5680  * Do a check when the kernel instantiates a new BPF token object from BPF FS
5681  * instance. This is also the point where LSM blob can be allocated for LSMs.
5682  *
5683  * Return: Returns 0 on success, error on failure.
5684  */
security_bpf_token_create(struct bpf_token * token,union bpf_attr * attr,const struct path * path)5685 int security_bpf_token_create(struct bpf_token *token, union bpf_attr *attr,
5686 			      const struct path *path)
5687 {
5688 	return call_int_hook(bpf_token_create, token, attr, path);
5689 }
5690 
5691 /**
5692  * security_bpf_token_cmd() - Check if BPF token is allowed to delegate
5693  * requested BPF syscall command
5694  * @token: BPF token object
5695  * @cmd: BPF syscall command requested to be delegated by BPF token
5696  *
5697  * Do a check when the kernel decides whether provided BPF token should allow
5698  * delegation of requested BPF syscall command.
5699  *
5700  * Return: Returns 0 on success, error on failure.
5701  */
security_bpf_token_cmd(const struct bpf_token * token,enum bpf_cmd cmd)5702 int security_bpf_token_cmd(const struct bpf_token *token, enum bpf_cmd cmd)
5703 {
5704 	return call_int_hook(bpf_token_cmd, token, cmd);
5705 }
5706 
5707 /**
5708  * security_bpf_token_capable() - Check if BPF token is allowed to delegate
5709  * requested BPF-related capability
5710  * @token: BPF token object
5711  * @cap: capabilities requested to be delegated by BPF token
5712  *
5713  * Do a check when the kernel decides whether provided BPF token should allow
5714  * delegation of requested BPF-related capabilities.
5715  *
5716  * Return: Returns 0 on success, error on failure.
5717  */
security_bpf_token_capable(const struct bpf_token * token,int cap)5718 int security_bpf_token_capable(const struct bpf_token *token, int cap)
5719 {
5720 	return call_int_hook(bpf_token_capable, token, cap);
5721 }
5722 
5723 /**
5724  * security_bpf_map_free() - Free a bpf map's LSM blob
5725  * @map: bpf map
5726  *
5727  * Clean up the security information stored inside bpf map.
5728  */
security_bpf_map_free(struct bpf_map * map)5729 void security_bpf_map_free(struct bpf_map *map)
5730 {
5731 	call_void_hook(bpf_map_free, map);
5732 }
5733 
5734 /**
5735  * security_bpf_prog_free() - Free a BPF program's LSM blob
5736  * @prog: BPF program struct
5737  *
5738  * Clean up the security information stored inside BPF program.
5739  */
security_bpf_prog_free(struct bpf_prog * prog)5740 void security_bpf_prog_free(struct bpf_prog *prog)
5741 {
5742 	call_void_hook(bpf_prog_free, prog);
5743 }
5744 
5745 /**
5746  * security_bpf_token_free() - Free a BPF token's LSM blob
5747  * @token: BPF token struct
5748  *
5749  * Clean up the security information stored inside BPF token.
5750  */
security_bpf_token_free(struct bpf_token * token)5751 void security_bpf_token_free(struct bpf_token *token)
5752 {
5753 	call_void_hook(bpf_token_free, token);
5754 }
5755 #endif /* CONFIG_BPF_SYSCALL */
5756 
5757 /**
5758  * security_locked_down() - Check if a kernel feature is allowed
5759  * @what: requested kernel feature
5760  *
5761  * Determine whether a kernel feature that potentially enables arbitrary code
5762  * execution in kernel space should be permitted.
5763  *
5764  * Return: Returns 0 if permission is granted.
5765  */
security_locked_down(enum lockdown_reason what)5766 int security_locked_down(enum lockdown_reason what)
5767 {
5768 	return call_int_hook(locked_down, what);
5769 }
5770 EXPORT_SYMBOL(security_locked_down);
5771 
5772 /**
5773  * security_bdev_alloc() - Allocate a block device LSM blob
5774  * @bdev: block device
5775  *
5776  * Allocate and attach a security structure to @bdev->bd_security.  The
5777  * security field is initialized to NULL when the bdev structure is
5778  * allocated.
5779  *
5780  * Return: Return 0 if operation was successful.
5781  */
security_bdev_alloc(struct block_device * bdev)5782 int security_bdev_alloc(struct block_device *bdev)
5783 {
5784 	int rc = 0;
5785 
5786 	rc = lsm_bdev_alloc(bdev);
5787 	if (unlikely(rc))
5788 		return rc;
5789 
5790 	rc = call_int_hook(bdev_alloc_security, bdev);
5791 	if (unlikely(rc))
5792 		security_bdev_free(bdev);
5793 
5794 	return rc;
5795 }
5796 EXPORT_SYMBOL(security_bdev_alloc);
5797 
5798 /**
5799  * security_bdev_free() - Free a block device's LSM blob
5800  * @bdev: block device
5801  *
5802  * Deallocate the bdev security structure and set @bdev->bd_security to NULL.
5803  */
security_bdev_free(struct block_device * bdev)5804 void security_bdev_free(struct block_device *bdev)
5805 {
5806 	if (!bdev->bd_security)
5807 		return;
5808 
5809 	call_void_hook(bdev_free_security, bdev);
5810 
5811 	kfree(bdev->bd_security);
5812 	bdev->bd_security = NULL;
5813 }
5814 EXPORT_SYMBOL(security_bdev_free);
5815 
5816 /**
5817  * security_bdev_setintegrity() - Set the device's integrity data
5818  * @bdev: block device
5819  * @type: type of integrity, e.g. hash digest, signature, etc
5820  * @value: the integrity value
5821  * @size: size of the integrity value
5822  *
5823  * Register a verified integrity measurement of a bdev with LSMs.
5824  * LSMs should free the previously saved data if @value is NULL.
5825  * Please note that the new hook should be invoked every time the security
5826  * information is updated to keep these data current. For example, in dm-verity,
5827  * if the mapping table is reloaded and configured to use a different dm-verity
5828  * target with a new roothash and signing information, the previously stored
5829  * data in the LSM blob will become obsolete. It is crucial to re-invoke the
5830  * hook to refresh these data and ensure they are up to date. This necessity
5831  * arises from the design of device-mapper, where a device-mapper device is
5832  * first created, and then targets are subsequently loaded into it. These
5833  * targets can be modified multiple times during the device's lifetime.
5834  * Therefore, while the LSM blob is allocated during the creation of the block
5835  * device, its actual contents are not initialized at this stage and can change
5836  * substantially over time. This includes alterations from data that the LSMs
5837  * 'trusts' to those they do not, making it essential to handle these changes
5838  * correctly. Failure to address this dynamic aspect could potentially allow
5839  * for bypassing LSM checks.
5840  *
5841  * Return: Returns 0 on success, negative values on failure.
5842  */
security_bdev_setintegrity(struct block_device * bdev,enum lsm_integrity_type type,const void * value,size_t size)5843 int security_bdev_setintegrity(struct block_device *bdev,
5844 			       enum lsm_integrity_type type, const void *value,
5845 			       size_t size)
5846 {
5847 	return call_int_hook(bdev_setintegrity, bdev, type, value, size);
5848 }
5849 EXPORT_SYMBOL(security_bdev_setintegrity);
5850 
5851 #ifdef CONFIG_PERF_EVENTS
5852 /**
5853  * security_perf_event_open() - Check if a perf event open is allowed
5854  * @attr: perf event attribute
5855  * @type: type of event
5856  *
5857  * Check whether the @type of perf_event_open syscall is allowed.
5858  *
5859  * Return: Returns 0 if permission is granted.
5860  */
security_perf_event_open(struct perf_event_attr * attr,int type)5861 int security_perf_event_open(struct perf_event_attr *attr, int type)
5862 {
5863 	return call_int_hook(perf_event_open, attr, type);
5864 }
5865 
5866 /**
5867  * security_perf_event_alloc() - Allocate a perf event LSM blob
5868  * @event: perf event
5869  *
5870  * Allocate and save perf_event security info.
5871  *
5872  * Return: Returns 0 on success, error on failure.
5873  */
security_perf_event_alloc(struct perf_event * event)5874 int security_perf_event_alloc(struct perf_event *event)
5875 {
5876 	int rc;
5877 
5878 	rc = lsm_blob_alloc(&event->security, blob_sizes.lbs_perf_event,
5879 			    GFP_KERNEL);
5880 	if (rc)
5881 		return rc;
5882 
5883 	rc = call_int_hook(perf_event_alloc, event);
5884 	if (rc) {
5885 		kfree(event->security);
5886 		event->security = NULL;
5887 	}
5888 	return rc;
5889 }
5890 
5891 /**
5892  * security_perf_event_free() - Free a perf event LSM blob
5893  * @event: perf event
5894  *
5895  * Release (free) perf_event security info.
5896  */
security_perf_event_free(struct perf_event * event)5897 void security_perf_event_free(struct perf_event *event)
5898 {
5899 	kfree(event->security);
5900 	event->security = NULL;
5901 }
5902 
5903 /**
5904  * security_perf_event_read() - Check if reading a perf event label is allowed
5905  * @event: perf event
5906  *
5907  * Read perf_event security info if allowed.
5908  *
5909  * Return: Returns 0 if permission is granted.
5910  */
security_perf_event_read(struct perf_event * event)5911 int security_perf_event_read(struct perf_event *event)
5912 {
5913 	return call_int_hook(perf_event_read, event);
5914 }
5915 
5916 /**
5917  * security_perf_event_write() - Check if writing a perf event label is allowed
5918  * @event: perf event
5919  *
5920  * Write perf_event security info if allowed.
5921  *
5922  * Return: Returns 0 if permission is granted.
5923  */
security_perf_event_write(struct perf_event * event)5924 int security_perf_event_write(struct perf_event *event)
5925 {
5926 	return call_int_hook(perf_event_write, event);
5927 }
5928 #endif /* CONFIG_PERF_EVENTS */
5929 
5930 #ifdef CONFIG_IO_URING
5931 /**
5932  * security_uring_override_creds() - Check if overriding creds is allowed
5933  * @new: new credentials
5934  *
5935  * Check if the current task, executing an io_uring operation, is allowed to
5936  * override it's credentials with @new.
5937  *
5938  * Return: Returns 0 if permission is granted.
5939  */
security_uring_override_creds(const struct cred * new)5940 int security_uring_override_creds(const struct cred *new)
5941 {
5942 	return call_int_hook(uring_override_creds, new);
5943 }
5944 
5945 /**
5946  * security_uring_sqpoll() - Check if IORING_SETUP_SQPOLL is allowed
5947  *
5948  * Check whether the current task is allowed to spawn a io_uring polling thread
5949  * (IORING_SETUP_SQPOLL).
5950  *
5951  * Return: Returns 0 if permission is granted.
5952  */
security_uring_sqpoll(void)5953 int security_uring_sqpoll(void)
5954 {
5955 	return call_int_hook(uring_sqpoll);
5956 }
5957 
5958 /**
5959  * security_uring_cmd() - Check if a io_uring passthrough command is allowed
5960  * @ioucmd: command
5961  *
5962  * Check whether the file_operations uring_cmd is allowed to run.
5963  *
5964  * Return: Returns 0 if permission is granted.
5965  */
security_uring_cmd(struct io_uring_cmd * ioucmd)5966 int security_uring_cmd(struct io_uring_cmd *ioucmd)
5967 {
5968 	return call_int_hook(uring_cmd, ioucmd);
5969 }
5970 #endif /* CONFIG_IO_URING */
5971 
5972 /**
5973  * security_initramfs_populated() - Notify LSMs that initramfs has been loaded
5974  *
5975  * Tells the LSMs the initramfs has been unpacked into the rootfs.
5976  */
security_initramfs_populated(void)5977 void security_initramfs_populated(void)
5978 {
5979 	call_void_hook(initramfs_populated);
5980 }
5981