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