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/mman.h>
23 #include <linux/mount.h>
24 #include <linux/personality.h>
25 #include <linux/backing-dev.h>
26 #include <linux/string.h>
27 #include <linux/xattr.h>
28 #include <linux/msg.h>
29 #include <linux/overflow.h>
30 #include <linux/perf_event.h>
31 #include <linux/fs.h>
32 #include <net/flow.h>
33 #include <net/sock.h>
34
35 #define SECURITY_HOOK_ACTIVE_KEY(HOOK, IDX) security_hook_active_##HOOK##_##IDX
36
37 /*
38 * Identifier for the LSM static calls.
39 * HOOK is an LSM hook as defined in linux/lsm_hookdefs.h
40 * IDX is the index of the static call. 0 <= NUM < MAX_LSM_COUNT
41 */
42 #define LSM_STATIC_CALL(HOOK, IDX) lsm_static_call_##HOOK##_##IDX
43
44 /*
45 * Call the macro M for each LSM hook MAX_LSM_COUNT times.
46 */
47 #define LSM_LOOP_UNROLL(M, ...) \
48 do { \
49 UNROLL(MAX_LSM_COUNT, M, __VA_ARGS__) \
50 } while (0)
51
52 #define LSM_DEFINE_UNROLL(M, ...) UNROLL(MAX_LSM_COUNT, M, __VA_ARGS__)
53
54 /*
55 * These are descriptions of the reasons that can be passed to the
56 * security_locked_down() LSM hook. Placing this array here allows
57 * all security modules to use the same descriptions for auditing
58 * purposes.
59 */
60 const char *const lockdown_reasons[LOCKDOWN_CONFIDENTIALITY_MAX + 1] = {
61 [LOCKDOWN_NONE] = "none",
62 [LOCKDOWN_MODULE_SIGNATURE] = "unsigned module loading",
63 [LOCKDOWN_DEV_MEM] = "/dev/mem,kmem,port",
64 [LOCKDOWN_EFI_TEST] = "/dev/efi_test access",
65 [LOCKDOWN_KEXEC] = "kexec of unsigned images",
66 [LOCKDOWN_HIBERNATION] = "hibernation",
67 [LOCKDOWN_PCI_ACCESS] = "direct PCI access",
68 [LOCKDOWN_IOPORT] = "raw io port access",
69 [LOCKDOWN_MSR] = "raw MSR access",
70 [LOCKDOWN_ACPI_TABLES] = "modifying ACPI tables",
71 [LOCKDOWN_DEVICE_TREE] = "modifying device tree contents",
72 [LOCKDOWN_PCMCIA_CIS] = "direct PCMCIA CIS storage",
73 [LOCKDOWN_TIOCSSERIAL] = "reconfiguration of serial port IO",
74 [LOCKDOWN_MODULE_PARAMETERS] = "unsafe module parameters",
75 [LOCKDOWN_MMIOTRACE] = "unsafe mmio",
76 [LOCKDOWN_DEBUGFS] = "debugfs access",
77 [LOCKDOWN_XMON_WR] = "xmon write access",
78 [LOCKDOWN_BPF_WRITE_USER] = "use of bpf to write user RAM",
79 [LOCKDOWN_DBG_WRITE_KERNEL] = "use of kgdb/kdb to write kernel RAM",
80 [LOCKDOWN_RTAS_ERROR_INJECTION] = "RTAS error injection",
81 [LOCKDOWN_INTEGRITY_MAX] = "integrity",
82 [LOCKDOWN_KCORE] = "/proc/kcore access",
83 [LOCKDOWN_KPROBES] = "use of kprobes",
84 [LOCKDOWN_BPF_READ_KERNEL] = "use of bpf to read kernel RAM",
85 [LOCKDOWN_DBG_READ_KERNEL] = "use of kgdb/kdb to read kernel RAM",
86 [LOCKDOWN_PERF] = "unsafe use of perf",
87 [LOCKDOWN_TRACEFS] = "use of tracefs",
88 [LOCKDOWN_XMON_RW] = "xmon read and write access",
89 [LOCKDOWN_XFRM_SECRET] = "xfrm SA secret",
90 [LOCKDOWN_CONFIDENTIALITY_MAX] = "confidentiality",
91 };
92
93 static BLOCKING_NOTIFIER_HEAD(blocking_lsm_notifier_chain);
94
95 static struct kmem_cache *lsm_file_cache;
96 static struct kmem_cache *lsm_inode_cache;
97
98 char *lsm_names;
99 static struct lsm_blob_sizes blob_sizes __ro_after_init;
100
101 /* Boot-time LSM user choice */
102 static __initdata const char *chosen_lsm_order;
103 static __initdata const char *chosen_major_lsm;
104
105 static __initconst const char *const builtin_lsm_order = CONFIG_LSM;
106
107 /* Ordered list of LSMs to initialize. */
108 static __initdata struct lsm_info *ordered_lsms[MAX_LSM_COUNT + 1];
109 static __initdata struct lsm_info *exclusive;
110
111 #ifdef CONFIG_HAVE_STATIC_CALL
112 #define LSM_HOOK_TRAMP(NAME, NUM) \
113 &STATIC_CALL_TRAMP(LSM_STATIC_CALL(NAME, NUM))
114 #else
115 #define LSM_HOOK_TRAMP(NAME, NUM) NULL
116 #endif
117
118 /*
119 * Define static calls and static keys for each LSM hook.
120 */
121 #define DEFINE_LSM_STATIC_CALL(NUM, NAME, RET, ...) \
122 DEFINE_STATIC_CALL_NULL(LSM_STATIC_CALL(NAME, NUM), \
123 *((RET(*)(__VA_ARGS__))NULL)); \
124 DEFINE_STATIC_KEY_FALSE(SECURITY_HOOK_ACTIVE_KEY(NAME, NUM));
125
126 #define LSM_HOOK(RET, DEFAULT, NAME, ...) \
127 LSM_DEFINE_UNROLL(DEFINE_LSM_STATIC_CALL, NAME, RET, __VA_ARGS__)
128 #include <linux/lsm_hook_defs.h>
129 #undef LSM_HOOK
130 #undef DEFINE_LSM_STATIC_CALL
131
132 /*
133 * Initialise a table of static calls for each LSM hook.
134 * DEFINE_STATIC_CALL_NULL invocation above generates a key (STATIC_CALL_KEY)
135 * and a trampoline (STATIC_CALL_TRAMP) which are used to call
136 * __static_call_update when updating the static call.
137 *
138 * The static calls table is used by early LSMs, some architectures can fault on
139 * unaligned accesses and the fault handling code may not be ready by then.
140 * Thus, the static calls table should be aligned to avoid any unhandled faults
141 * in early init.
142 */
143 struct lsm_static_calls_table
144 static_calls_table __ro_after_init __aligned(sizeof(u64)) = {
145 #define INIT_LSM_STATIC_CALL(NUM, NAME) \
146 (struct lsm_static_call) { \
147 .key = &STATIC_CALL_KEY(LSM_STATIC_CALL(NAME, NUM)), \
148 .trampoline = LSM_HOOK_TRAMP(NAME, NUM), \
149 .active = &SECURITY_HOOK_ACTIVE_KEY(NAME, NUM), \
150 },
151 #define LSM_HOOK(RET, DEFAULT, NAME, ...) \
152 .NAME = { \
153 LSM_DEFINE_UNROLL(INIT_LSM_STATIC_CALL, NAME) \
154 },
155 #include <linux/lsm_hook_defs.h>
156 #undef LSM_HOOK
157 #undef INIT_LSM_STATIC_CALL
158 };
159
160 static __initdata bool debug;
161 #define init_debug(...) \
162 do { \
163 if (debug) \
164 pr_info(__VA_ARGS__); \
165 } while (0)
166
is_enabled(struct lsm_info * lsm)167 static bool __init is_enabled(struct lsm_info *lsm)
168 {
169 if (!lsm->enabled)
170 return false;
171
172 return *lsm->enabled;
173 }
174
175 /* Mark an LSM's enabled flag. */
176 static int lsm_enabled_true __initdata = 1;
177 static int lsm_enabled_false __initdata = 0;
set_enabled(struct lsm_info * lsm,bool enabled)178 static void __init set_enabled(struct lsm_info *lsm, bool enabled)
179 {
180 /*
181 * When an LSM hasn't configured an enable variable, we can use
182 * a hard-coded location for storing the default enabled state.
183 */
184 if (!lsm->enabled) {
185 if (enabled)
186 lsm->enabled = &lsm_enabled_true;
187 else
188 lsm->enabled = &lsm_enabled_false;
189 } else if (lsm->enabled == &lsm_enabled_true) {
190 if (!enabled)
191 lsm->enabled = &lsm_enabled_false;
192 } else if (lsm->enabled == &lsm_enabled_false) {
193 if (enabled)
194 lsm->enabled = &lsm_enabled_true;
195 } else {
196 *lsm->enabled = enabled;
197 }
198 }
199
200 /* Is an LSM already listed in the ordered LSMs list? */
exists_ordered_lsm(struct lsm_info * lsm)201 static bool __init exists_ordered_lsm(struct lsm_info *lsm)
202 {
203 struct lsm_info **check;
204
205 for (check = ordered_lsms; *check; check++)
206 if (*check == lsm)
207 return true;
208
209 return false;
210 }
211
212 /* Append an LSM to the list of ordered LSMs to initialize. */
213 static int last_lsm __initdata;
append_ordered_lsm(struct lsm_info * lsm,const char * from)214 static void __init append_ordered_lsm(struct lsm_info *lsm, const char *from)
215 {
216 /* Ignore duplicate selections. */
217 if (exists_ordered_lsm(lsm))
218 return;
219
220 if (WARN(last_lsm == MAX_LSM_COUNT, "%s: out of LSM static calls!?\n", from))
221 return;
222
223 /* Enable this LSM, if it is not already set. */
224 if (!lsm->enabled)
225 lsm->enabled = &lsm_enabled_true;
226 ordered_lsms[last_lsm++] = lsm;
227
228 init_debug("%s ordered: %s (%s)\n", from, lsm->name,
229 is_enabled(lsm) ? "enabled" : "disabled");
230 }
231
232 /* Is an LSM allowed to be initialized? */
lsm_allowed(struct lsm_info * lsm)233 static bool __init lsm_allowed(struct lsm_info *lsm)
234 {
235 /* Skip if the LSM is disabled. */
236 if (!is_enabled(lsm))
237 return false;
238
239 /* Not allowed if another exclusive LSM already initialized. */
240 if ((lsm->flags & LSM_FLAG_EXCLUSIVE) && exclusive) {
241 init_debug("exclusive disabled: %s\n", lsm->name);
242 return false;
243 }
244
245 return true;
246 }
247
lsm_set_blob_size(int * need,int * lbs)248 static void __init lsm_set_blob_size(int *need, int *lbs)
249 {
250 int offset;
251
252 if (*need <= 0)
253 return;
254
255 offset = ALIGN(*lbs, sizeof(void *));
256 *lbs = offset + *need;
257 *need = offset;
258 }
259
lsm_set_blob_sizes(struct lsm_blob_sizes * needed)260 static void __init lsm_set_blob_sizes(struct lsm_blob_sizes *needed)
261 {
262 if (!needed)
263 return;
264
265 lsm_set_blob_size(&needed->lbs_cred, &blob_sizes.lbs_cred);
266 lsm_set_blob_size(&needed->lbs_file, &blob_sizes.lbs_file);
267 lsm_set_blob_size(&needed->lbs_ib, &blob_sizes.lbs_ib);
268 /*
269 * The inode blob gets an rcu_head in addition to
270 * what the modules might need.
271 */
272 if (needed->lbs_inode && blob_sizes.lbs_inode == 0)
273 blob_sizes.lbs_inode = sizeof(struct rcu_head);
274 lsm_set_blob_size(&needed->lbs_inode, &blob_sizes.lbs_inode);
275 lsm_set_blob_size(&needed->lbs_ipc, &blob_sizes.lbs_ipc);
276 lsm_set_blob_size(&needed->lbs_key, &blob_sizes.lbs_key);
277 lsm_set_blob_size(&needed->lbs_msg_msg, &blob_sizes.lbs_msg_msg);
278 lsm_set_blob_size(&needed->lbs_perf_event, &blob_sizes.lbs_perf_event);
279 lsm_set_blob_size(&needed->lbs_sock, &blob_sizes.lbs_sock);
280 lsm_set_blob_size(&needed->lbs_superblock, &blob_sizes.lbs_superblock);
281 lsm_set_blob_size(&needed->lbs_task, &blob_sizes.lbs_task);
282 lsm_set_blob_size(&needed->lbs_tun_dev, &blob_sizes.lbs_tun_dev);
283 lsm_set_blob_size(&needed->lbs_xattr_count,
284 &blob_sizes.lbs_xattr_count);
285 lsm_set_blob_size(&needed->lbs_bdev, &blob_sizes.lbs_bdev);
286 }
287
288 /* Prepare LSM for initialization. */
prepare_lsm(struct lsm_info * lsm)289 static void __init prepare_lsm(struct lsm_info *lsm)
290 {
291 int enabled = lsm_allowed(lsm);
292
293 /* Record enablement (to handle any following exclusive LSMs). */
294 set_enabled(lsm, enabled);
295
296 /* If enabled, do pre-initialization work. */
297 if (enabled) {
298 if ((lsm->flags & LSM_FLAG_EXCLUSIVE) && !exclusive) {
299 exclusive = lsm;
300 init_debug("exclusive chosen: %s\n", lsm->name);
301 }
302
303 lsm_set_blob_sizes(lsm->blobs);
304 }
305 }
306
307 /* Initialize a given LSM, if it is enabled. */
initialize_lsm(struct lsm_info * lsm)308 static void __init initialize_lsm(struct lsm_info *lsm)
309 {
310 if (is_enabled(lsm)) {
311 int ret;
312
313 init_debug("initializing %s\n", lsm->name);
314 ret = lsm->init();
315 WARN(ret, "%s failed to initialize: %d\n", lsm->name, ret);
316 }
317 }
318
319 /*
320 * Current index to use while initializing the lsm id list.
321 */
322 u32 lsm_active_cnt __ro_after_init;
323 const struct lsm_id *lsm_idlist[MAX_LSM_COUNT];
324
325 /* Populate ordered LSMs list from comma-separated LSM name list. */
ordered_lsm_parse(const char * order,const char * origin)326 static void __init ordered_lsm_parse(const char *order, const char *origin)
327 {
328 struct lsm_info *lsm;
329 char *sep, *name, *next;
330
331 /* LSM_ORDER_FIRST is always first. */
332 for (lsm = __start_lsm_info; lsm < __end_lsm_info; lsm++) {
333 if (lsm->order == LSM_ORDER_FIRST)
334 append_ordered_lsm(lsm, " first");
335 }
336
337 /* Process "security=", if given. */
338 if (chosen_major_lsm) {
339 struct lsm_info *major;
340
341 /*
342 * To match the original "security=" behavior, this
343 * explicitly does NOT fallback to another Legacy Major
344 * if the selected one was separately disabled: disable
345 * all non-matching Legacy Major LSMs.
346 */
347 for (major = __start_lsm_info; major < __end_lsm_info;
348 major++) {
349 if ((major->flags & LSM_FLAG_LEGACY_MAJOR) &&
350 strcmp(major->name, chosen_major_lsm) != 0) {
351 set_enabled(major, false);
352 init_debug("security=%s disabled: %s (only one legacy major LSM)\n",
353 chosen_major_lsm, major->name);
354 }
355 }
356 }
357
358 sep = kstrdup(order, GFP_KERNEL);
359 next = sep;
360 /* Walk the list, looking for matching LSMs. */
361 while ((name = strsep(&next, ",")) != NULL) {
362 bool found = false;
363
364 for (lsm = __start_lsm_info; lsm < __end_lsm_info; lsm++) {
365 if (strcmp(lsm->name, name) == 0) {
366 if (lsm->order == LSM_ORDER_MUTABLE)
367 append_ordered_lsm(lsm, origin);
368 found = true;
369 }
370 }
371
372 if (!found)
373 init_debug("%s ignored: %s (not built into kernel)\n",
374 origin, name);
375 }
376
377 /* Process "security=", if given. */
378 if (chosen_major_lsm) {
379 for (lsm = __start_lsm_info; lsm < __end_lsm_info; lsm++) {
380 if (exists_ordered_lsm(lsm))
381 continue;
382 if (strcmp(lsm->name, chosen_major_lsm) == 0)
383 append_ordered_lsm(lsm, "security=");
384 }
385 }
386
387 /* LSM_ORDER_LAST is always last. */
388 for (lsm = __start_lsm_info; lsm < __end_lsm_info; lsm++) {
389 if (lsm->order == LSM_ORDER_LAST)
390 append_ordered_lsm(lsm, " last");
391 }
392
393 /* Disable all LSMs not in the ordered list. */
394 for (lsm = __start_lsm_info; lsm < __end_lsm_info; lsm++) {
395 if (exists_ordered_lsm(lsm))
396 continue;
397 set_enabled(lsm, false);
398 init_debug("%s skipped: %s (not in requested order)\n",
399 origin, lsm->name);
400 }
401
402 kfree(sep);
403 }
404
lsm_static_call_init(struct security_hook_list * hl)405 static void __init lsm_static_call_init(struct security_hook_list *hl)
406 {
407 struct lsm_static_call *scall = hl->scalls;
408 int i;
409
410 for (i = 0; i < MAX_LSM_COUNT; i++) {
411 /* Update the first static call that is not used yet */
412 if (!scall->hl) {
413 __static_call_update(scall->key, scall->trampoline,
414 hl->hook.lsm_func_addr);
415 scall->hl = hl;
416 static_branch_enable(scall->active);
417 return;
418 }
419 scall++;
420 }
421 panic("%s - Ran out of static slots.\n", __func__);
422 }
423
424 static void __init lsm_early_cred(struct cred *cred);
425 static void __init lsm_early_task(struct task_struct *task);
426
427 static int lsm_append(const char *new, char **result);
428
report_lsm_order(void)429 static void __init report_lsm_order(void)
430 {
431 struct lsm_info **lsm, *early;
432 int first = 0;
433
434 pr_info("initializing lsm=");
435
436 /* Report each enabled LSM name, comma separated. */
437 for (early = __start_early_lsm_info;
438 early < __end_early_lsm_info; early++)
439 if (is_enabled(early))
440 pr_cont("%s%s", first++ == 0 ? "" : ",", early->name);
441 for (lsm = ordered_lsms; *lsm; lsm++)
442 if (is_enabled(*lsm))
443 pr_cont("%s%s", first++ == 0 ? "" : ",", (*lsm)->name);
444
445 pr_cont("\n");
446 }
447
ordered_lsm_init(void)448 static void __init ordered_lsm_init(void)
449 {
450 struct lsm_info **lsm;
451
452 if (chosen_lsm_order) {
453 if (chosen_major_lsm) {
454 pr_warn("security=%s is ignored because it is superseded by lsm=%s\n",
455 chosen_major_lsm, chosen_lsm_order);
456 chosen_major_lsm = NULL;
457 }
458 ordered_lsm_parse(chosen_lsm_order, "cmdline");
459 } else
460 ordered_lsm_parse(builtin_lsm_order, "builtin");
461
462 for (lsm = ordered_lsms; *lsm; lsm++)
463 prepare_lsm(*lsm);
464
465 report_lsm_order();
466
467 init_debug("cred blob size = %d\n", blob_sizes.lbs_cred);
468 init_debug("file blob size = %d\n", blob_sizes.lbs_file);
469 init_debug("ib blob size = %d\n", blob_sizes.lbs_ib);
470 init_debug("inode blob size = %d\n", blob_sizes.lbs_inode);
471 init_debug("ipc blob size = %d\n", blob_sizes.lbs_ipc);
472 #ifdef CONFIG_KEYS
473 init_debug("key blob size = %d\n", blob_sizes.lbs_key);
474 #endif /* CONFIG_KEYS */
475 init_debug("msg_msg blob size = %d\n", blob_sizes.lbs_msg_msg);
476 init_debug("sock blob size = %d\n", blob_sizes.lbs_sock);
477 init_debug("superblock blob size = %d\n", blob_sizes.lbs_superblock);
478 init_debug("perf event blob size = %d\n", blob_sizes.lbs_perf_event);
479 init_debug("task blob size = %d\n", blob_sizes.lbs_task);
480 init_debug("tun device blob size = %d\n", blob_sizes.lbs_tun_dev);
481 init_debug("xattr slots = %d\n", blob_sizes.lbs_xattr_count);
482 init_debug("bdev blob size = %d\n", blob_sizes.lbs_bdev);
483
484 /*
485 * Create any kmem_caches needed for blobs
486 */
487 if (blob_sizes.lbs_file)
488 lsm_file_cache = kmem_cache_create("lsm_file_cache",
489 blob_sizes.lbs_file, 0,
490 SLAB_PANIC, NULL);
491 if (blob_sizes.lbs_inode)
492 lsm_inode_cache = kmem_cache_create("lsm_inode_cache",
493 blob_sizes.lbs_inode, 0,
494 SLAB_PANIC, NULL);
495
496 lsm_early_cred((struct cred *) current->cred);
497 lsm_early_task(current);
498 for (lsm = ordered_lsms; *lsm; lsm++)
499 initialize_lsm(*lsm);
500 }
501
early_security_init(void)502 int __init early_security_init(void)
503 {
504 struct lsm_info *lsm;
505
506 for (lsm = __start_early_lsm_info; lsm < __end_early_lsm_info; lsm++) {
507 if (!lsm->enabled)
508 lsm->enabled = &lsm_enabled_true;
509 prepare_lsm(lsm);
510 initialize_lsm(lsm);
511 }
512
513 return 0;
514 }
515
516 /**
517 * security_init - initializes the security framework
518 *
519 * This should be called early in the kernel initialization sequence.
520 */
security_init(void)521 int __init security_init(void)
522 {
523 struct lsm_info *lsm;
524
525 init_debug("legacy security=%s\n", chosen_major_lsm ? : " *unspecified*");
526 init_debug(" CONFIG_LSM=%s\n", builtin_lsm_order);
527 init_debug("boot arg lsm=%s\n", chosen_lsm_order ? : " *unspecified*");
528
529 /*
530 * Append the names of the early LSM modules now that kmalloc() is
531 * available
532 */
533 for (lsm = __start_early_lsm_info; lsm < __end_early_lsm_info; lsm++) {
534 init_debug(" early started: %s (%s)\n", lsm->name,
535 is_enabled(lsm) ? "enabled" : "disabled");
536 if (lsm->enabled)
537 lsm_append(lsm->name, &lsm_names);
538 }
539
540 /* Load LSMs in specified order. */
541 ordered_lsm_init();
542
543 return 0;
544 }
545
546 /* Save user chosen LSM */
choose_major_lsm(char * str)547 static int __init choose_major_lsm(char *str)
548 {
549 chosen_major_lsm = str;
550 return 1;
551 }
552 __setup("security=", choose_major_lsm);
553
554 /* Explicitly choose LSM initialization order. */
choose_lsm_order(char * str)555 static int __init choose_lsm_order(char *str)
556 {
557 chosen_lsm_order = str;
558 return 1;
559 }
560 __setup("lsm=", choose_lsm_order);
561
562 /* Enable LSM order debugging. */
enable_debug(char * str)563 static int __init enable_debug(char *str)
564 {
565 debug = true;
566 return 1;
567 }
568 __setup("lsm.debug", enable_debug);
569
match_last_lsm(const char * list,const char * lsm)570 static bool match_last_lsm(const char *list, const char *lsm)
571 {
572 const char *last;
573
574 if (WARN_ON(!list || !lsm))
575 return false;
576 last = strrchr(list, ',');
577 if (last)
578 /* Pass the comma, strcmp() will check for '\0' */
579 last++;
580 else
581 last = list;
582 return !strcmp(last, lsm);
583 }
584
lsm_append(const char * new,char ** result)585 static int lsm_append(const char *new, char **result)
586 {
587 char *cp;
588
589 if (*result == NULL) {
590 *result = kstrdup(new, GFP_KERNEL);
591 if (*result == NULL)
592 return -ENOMEM;
593 } else {
594 /* Check if it is the last registered name */
595 if (match_last_lsm(*result, new))
596 return 0;
597 cp = kasprintf(GFP_KERNEL, "%s,%s", *result, new);
598 if (cp == NULL)
599 return -ENOMEM;
600 kfree(*result);
601 *result = cp;
602 }
603 return 0;
604 }
605
606 /**
607 * security_add_hooks - Add a modules hooks to the hook lists.
608 * @hooks: the hooks to add
609 * @count: the number of hooks to add
610 * @lsmid: the identification information for the security module
611 *
612 * Each LSM has to register its hooks with the infrastructure.
613 */
security_add_hooks(struct security_hook_list * hooks,int count,const struct lsm_id * lsmid)614 void __init security_add_hooks(struct security_hook_list *hooks, int count,
615 const struct lsm_id *lsmid)
616 {
617 int i;
618
619 /*
620 * A security module may call security_add_hooks() more
621 * than once during initialization, and LSM initialization
622 * is serialized. Landlock is one such case.
623 * Look at the previous entry, if there is one, for duplication.
624 */
625 if (lsm_active_cnt == 0 || lsm_idlist[lsm_active_cnt - 1] != lsmid) {
626 if (lsm_active_cnt >= MAX_LSM_COUNT)
627 panic("%s Too many LSMs registered.\n", __func__);
628 lsm_idlist[lsm_active_cnt++] = lsmid;
629 }
630
631 for (i = 0; i < count; i++) {
632 hooks[i].lsmid = lsmid;
633 lsm_static_call_init(&hooks[i]);
634 }
635
636 /*
637 * Don't try to append during early_security_init(), we'll come back
638 * and fix this up afterwards.
639 */
640 if (slab_is_available()) {
641 if (lsm_append(lsmid->name, &lsm_names) < 0)
642 panic("%s - Cannot get early memory.\n", __func__);
643 }
644 }
645
call_blocking_lsm_notifier(enum lsm_event event,void * data)646 int call_blocking_lsm_notifier(enum lsm_event event, void *data)
647 {
648 return blocking_notifier_call_chain(&blocking_lsm_notifier_chain,
649 event, data);
650 }
651 EXPORT_SYMBOL(call_blocking_lsm_notifier);
652
register_blocking_lsm_notifier(struct notifier_block * nb)653 int register_blocking_lsm_notifier(struct notifier_block *nb)
654 {
655 return blocking_notifier_chain_register(&blocking_lsm_notifier_chain,
656 nb);
657 }
658 EXPORT_SYMBOL(register_blocking_lsm_notifier);
659
unregister_blocking_lsm_notifier(struct notifier_block * nb)660 int unregister_blocking_lsm_notifier(struct notifier_block *nb)
661 {
662 return blocking_notifier_chain_unregister(&blocking_lsm_notifier_chain,
663 nb);
664 }
665 EXPORT_SYMBOL(unregister_blocking_lsm_notifier);
666
667 /**
668 * lsm_blob_alloc - allocate a composite blob
669 * @dest: the destination for the blob
670 * @size: the size of the blob
671 * @gfp: allocation type
672 *
673 * Allocate a blob for all the modules
674 *
675 * Returns 0, or -ENOMEM if memory can't be allocated.
676 */
lsm_blob_alloc(void ** dest,size_t size,gfp_t gfp)677 static int lsm_blob_alloc(void **dest, size_t size, gfp_t gfp)
678 {
679 if (size == 0) {
680 *dest = NULL;
681 return 0;
682 }
683
684 *dest = kzalloc(size, gfp);
685 if (*dest == NULL)
686 return -ENOMEM;
687 return 0;
688 }
689
690 /**
691 * lsm_cred_alloc - allocate a composite cred blob
692 * @cred: the cred that needs a blob
693 * @gfp: allocation type
694 *
695 * Allocate the cred blob for all the modules
696 *
697 * Returns 0, or -ENOMEM if memory can't be allocated.
698 */
lsm_cred_alloc(struct cred * cred,gfp_t gfp)699 static int lsm_cred_alloc(struct cred *cred, gfp_t gfp)
700 {
701 return lsm_blob_alloc(&cred->security, blob_sizes.lbs_cred, gfp);
702 }
703
704 /**
705 * lsm_early_cred - during initialization allocate a composite cred blob
706 * @cred: the cred that needs a blob
707 *
708 * Allocate the cred blob for all the modules
709 */
lsm_early_cred(struct cred * cred)710 static void __init lsm_early_cred(struct cred *cred)
711 {
712 int rc = lsm_cred_alloc(cred, GFP_KERNEL);
713
714 if (rc)
715 panic("%s: Early cred alloc failed.\n", __func__);
716 }
717
718 /**
719 * lsm_file_alloc - allocate a composite file blob
720 * @file: the file that needs a blob
721 *
722 * Allocate the file blob for all the modules
723 *
724 * Returns 0, or -ENOMEM if memory can't be allocated.
725 */
lsm_file_alloc(struct file * file)726 static int lsm_file_alloc(struct file *file)
727 {
728 if (!lsm_file_cache) {
729 file->f_security = NULL;
730 return 0;
731 }
732
733 file->f_security = kmem_cache_zalloc(lsm_file_cache, GFP_KERNEL);
734 if (file->f_security == NULL)
735 return -ENOMEM;
736 return 0;
737 }
738
739 /**
740 * lsm_inode_alloc - allocate a composite inode blob
741 * @inode: the inode that needs a blob
742 * @gfp: allocation flags
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,gfp_t gfp)748 static int lsm_inode_alloc(struct inode *inode, gfp_t gfp)
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);
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 * If execveat(2) is called with the AT_EXECVE_CHECK flag, bprm->is_check is
1252 * set. The result must be the same as without this flag even if the execution
1253 * will never really happen and @bprm will always be dropped.
1254 *
1255 * This hook must not change current->cred, only @bprm->cred.
1256 *
1257 * Return: Returns 0 if the hook is successful and permission is granted.
1258 */
security_bprm_creds_for_exec(struct linux_binprm * bprm)1259 int security_bprm_creds_for_exec(struct linux_binprm *bprm)
1260 {
1261 return call_int_hook(bprm_creds_for_exec, bprm);
1262 }
1263
1264 /**
1265 * security_bprm_creds_from_file() - Update linux_binprm creds based on file
1266 * @bprm: binary program information
1267 * @file: associated file
1268 *
1269 * If @file is setpcap, suid, sgid or otherwise marked to change privilege upon
1270 * exec, update @bprm->cred to reflect that change. This is called after
1271 * finding the binary that will be executed without an interpreter. This
1272 * ensures that the credentials will not be derived from a script that the
1273 * binary will need to reopen, which when reopend may end up being a completely
1274 * different file. This hook may also optionally check permissions (e.g. for
1275 * transitions between security domains). The hook must set @bprm->secureexec
1276 * to 1 if AT_SECURE should be set to request libc enable secure mode. The
1277 * hook must add to @bprm->per_clear any personality flags that should be
1278 * cleared from current->personality. @bprm contains the linux_binprm
1279 * structure.
1280 *
1281 * Return: Returns 0 if the hook is successful and permission is granted.
1282 */
security_bprm_creds_from_file(struct linux_binprm * bprm,const struct file * file)1283 int security_bprm_creds_from_file(struct linux_binprm *bprm, const struct file *file)
1284 {
1285 return call_int_hook(bprm_creds_from_file, bprm, file);
1286 }
1287
1288 /**
1289 * security_bprm_check() - Mediate binary handler search
1290 * @bprm: binary program information
1291 *
1292 * This hook mediates the point when a search for a binary handler will begin.
1293 * It allows a check against the @bprm->cred->security value which was set in
1294 * the preceding creds_for_exec call. The argv list and envp list are reliably
1295 * available in @bprm. This hook may be called multiple times during a single
1296 * execve. @bprm contains the linux_binprm structure.
1297 *
1298 * Return: Returns 0 if the hook is successful and permission is granted.
1299 */
security_bprm_check(struct linux_binprm * bprm)1300 int security_bprm_check(struct linux_binprm *bprm)
1301 {
1302 return call_int_hook(bprm_check_security, bprm);
1303 }
1304
1305 /**
1306 * security_bprm_committing_creds() - Install creds for a process during exec()
1307 * @bprm: binary program information
1308 *
1309 * Prepare to install the new security attributes of a process being
1310 * transformed by an execve operation, based on the old credentials pointed to
1311 * by @current->cred and the information set in @bprm->cred by the
1312 * bprm_creds_for_exec hook. @bprm points to the linux_binprm structure. This
1313 * hook is a good place to perform state changes on the process such as closing
1314 * open file descriptors to which access will no longer be granted when the
1315 * attributes are changed. This is called immediately before commit_creds().
1316 */
security_bprm_committing_creds(const struct linux_binprm * bprm)1317 void security_bprm_committing_creds(const struct linux_binprm *bprm)
1318 {
1319 call_void_hook(bprm_committing_creds, bprm);
1320 }
1321
1322 /**
1323 * security_bprm_committed_creds() - Tidy up after cred install during exec()
1324 * @bprm: binary program information
1325 *
1326 * Tidy up after the installation of the new security attributes of a process
1327 * being transformed by an execve operation. The new credentials have, by this
1328 * point, been set to @current->cred. @bprm points to the linux_binprm
1329 * structure. This hook is a good place to perform state changes on the
1330 * process such as clearing out non-inheritable signal state. This is called
1331 * immediately after commit_creds().
1332 */
security_bprm_committed_creds(const struct linux_binprm * bprm)1333 void security_bprm_committed_creds(const struct linux_binprm *bprm)
1334 {
1335 call_void_hook(bprm_committed_creds, bprm);
1336 }
1337
1338 /**
1339 * security_fs_context_submount() - Initialise fc->security
1340 * @fc: new filesystem context
1341 * @reference: dentry reference for submount/remount
1342 *
1343 * Fill out the ->security field for a new fs_context.
1344 *
1345 * Return: Returns 0 on success or negative error code on failure.
1346 */
security_fs_context_submount(struct fs_context * fc,struct super_block * reference)1347 int security_fs_context_submount(struct fs_context *fc, struct super_block *reference)
1348 {
1349 return call_int_hook(fs_context_submount, fc, reference);
1350 }
1351
1352 /**
1353 * security_fs_context_dup() - Duplicate a fs_context LSM blob
1354 * @fc: destination filesystem context
1355 * @src_fc: source filesystem context
1356 *
1357 * Allocate and attach a security structure to sc->security. This pointer is
1358 * initialised to NULL by the caller. @fc indicates the new filesystem context.
1359 * @src_fc indicates the original filesystem context.
1360 *
1361 * Return: Returns 0 on success or a negative error code on failure.
1362 */
security_fs_context_dup(struct fs_context * fc,struct fs_context * src_fc)1363 int security_fs_context_dup(struct fs_context *fc, struct fs_context *src_fc)
1364 {
1365 return call_int_hook(fs_context_dup, fc, src_fc);
1366 }
1367
1368 /**
1369 * security_fs_context_parse_param() - Configure a filesystem context
1370 * @fc: filesystem context
1371 * @param: filesystem parameter
1372 *
1373 * Userspace provided a parameter to configure a superblock. The LSM can
1374 * consume the parameter or return it to the caller for use elsewhere.
1375 *
1376 * Return: If the parameter is used by the LSM it should return 0, if it is
1377 * returned to the caller -ENOPARAM is returned, otherwise a negative
1378 * error code is returned.
1379 */
security_fs_context_parse_param(struct fs_context * fc,struct fs_parameter * param)1380 int security_fs_context_parse_param(struct fs_context *fc,
1381 struct fs_parameter *param)
1382 {
1383 struct lsm_static_call *scall;
1384 int trc;
1385 int rc = -ENOPARAM;
1386
1387 lsm_for_each_hook(scall, fs_context_parse_param) {
1388 trc = scall->hl->hook.fs_context_parse_param(fc, param);
1389 if (trc == 0)
1390 rc = 0;
1391 else if (trc != -ENOPARAM)
1392 return trc;
1393 }
1394 return rc;
1395 }
1396
1397 /**
1398 * security_sb_alloc() - Allocate a super_block LSM blob
1399 * @sb: filesystem superblock
1400 *
1401 * Allocate and attach a security structure to the sb->s_security field. The
1402 * s_security field is initialized to NULL when the structure is allocated.
1403 * @sb contains the super_block structure to be modified.
1404 *
1405 * Return: Returns 0 if operation was successful.
1406 */
security_sb_alloc(struct super_block * sb)1407 int security_sb_alloc(struct super_block *sb)
1408 {
1409 int rc = lsm_superblock_alloc(sb);
1410
1411 if (unlikely(rc))
1412 return rc;
1413 rc = call_int_hook(sb_alloc_security, sb);
1414 if (unlikely(rc))
1415 security_sb_free(sb);
1416 return rc;
1417 }
1418
1419 /**
1420 * security_sb_delete() - Release super_block LSM associated objects
1421 * @sb: filesystem superblock
1422 *
1423 * Release objects tied to a superblock (e.g. inodes). @sb contains the
1424 * super_block structure being released.
1425 */
security_sb_delete(struct super_block * sb)1426 void security_sb_delete(struct super_block *sb)
1427 {
1428 call_void_hook(sb_delete, sb);
1429 }
1430
1431 /**
1432 * security_sb_free() - Free a super_block LSM blob
1433 * @sb: filesystem superblock
1434 *
1435 * Deallocate and clear the sb->s_security field. @sb contains the super_block
1436 * structure to be modified.
1437 */
security_sb_free(struct super_block * sb)1438 void security_sb_free(struct super_block *sb)
1439 {
1440 call_void_hook(sb_free_security, sb);
1441 kfree(sb->s_security);
1442 sb->s_security = NULL;
1443 }
1444
1445 /**
1446 * security_free_mnt_opts() - Free memory associated with mount options
1447 * @mnt_opts: LSM processed mount options
1448 *
1449 * Free memory associated with @mnt_ops.
1450 */
security_free_mnt_opts(void ** mnt_opts)1451 void security_free_mnt_opts(void **mnt_opts)
1452 {
1453 if (!*mnt_opts)
1454 return;
1455 call_void_hook(sb_free_mnt_opts, *mnt_opts);
1456 *mnt_opts = NULL;
1457 }
1458 EXPORT_SYMBOL(security_free_mnt_opts);
1459
1460 /**
1461 * security_sb_eat_lsm_opts() - Consume LSM mount options
1462 * @options: mount options
1463 * @mnt_opts: LSM processed mount options
1464 *
1465 * Eat (scan @options) and save them in @mnt_opts.
1466 *
1467 * Return: Returns 0 on success, negative values on failure.
1468 */
security_sb_eat_lsm_opts(char * options,void ** mnt_opts)1469 int security_sb_eat_lsm_opts(char *options, void **mnt_opts)
1470 {
1471 return call_int_hook(sb_eat_lsm_opts, options, mnt_opts);
1472 }
1473 EXPORT_SYMBOL(security_sb_eat_lsm_opts);
1474
1475 /**
1476 * security_sb_mnt_opts_compat() - Check if new mount options are allowed
1477 * @sb: filesystem superblock
1478 * @mnt_opts: new mount options
1479 *
1480 * Determine if the new mount options in @mnt_opts are allowed given the
1481 * existing mounted filesystem at @sb. @sb superblock being compared.
1482 *
1483 * Return: Returns 0 if options are compatible.
1484 */
security_sb_mnt_opts_compat(struct super_block * sb,void * mnt_opts)1485 int security_sb_mnt_opts_compat(struct super_block *sb,
1486 void *mnt_opts)
1487 {
1488 return call_int_hook(sb_mnt_opts_compat, sb, mnt_opts);
1489 }
1490 EXPORT_SYMBOL(security_sb_mnt_opts_compat);
1491
1492 /**
1493 * security_sb_remount() - Verify no incompatible mount changes during remount
1494 * @sb: filesystem superblock
1495 * @mnt_opts: (re)mount options
1496 *
1497 * Extracts security system specific mount options and verifies no changes are
1498 * being made to those options.
1499 *
1500 * Return: Returns 0 if permission is granted.
1501 */
security_sb_remount(struct super_block * sb,void * mnt_opts)1502 int security_sb_remount(struct super_block *sb,
1503 void *mnt_opts)
1504 {
1505 return call_int_hook(sb_remount, sb, mnt_opts);
1506 }
1507 EXPORT_SYMBOL(security_sb_remount);
1508
1509 /**
1510 * security_sb_kern_mount() - Check if a kernel mount is allowed
1511 * @sb: filesystem superblock
1512 *
1513 * Mount this @sb if allowed by permissions.
1514 *
1515 * Return: Returns 0 if permission is granted.
1516 */
security_sb_kern_mount(const struct super_block * sb)1517 int security_sb_kern_mount(const struct super_block *sb)
1518 {
1519 return call_int_hook(sb_kern_mount, sb);
1520 }
1521
1522 /**
1523 * security_sb_show_options() - Output the mount options for a superblock
1524 * @m: output file
1525 * @sb: filesystem superblock
1526 *
1527 * Show (print on @m) mount options for this @sb.
1528 *
1529 * Return: Returns 0 on success, negative values on failure.
1530 */
security_sb_show_options(struct seq_file * m,struct super_block * sb)1531 int security_sb_show_options(struct seq_file *m, struct super_block *sb)
1532 {
1533 return call_int_hook(sb_show_options, m, sb);
1534 }
1535
1536 /**
1537 * security_sb_statfs() - Check if accessing fs stats is allowed
1538 * @dentry: superblock handle
1539 *
1540 * Check permission before obtaining filesystem statistics for the @mnt
1541 * mountpoint. @dentry is a handle on the superblock for the filesystem.
1542 *
1543 * Return: Returns 0 if permission is granted.
1544 */
security_sb_statfs(struct dentry * dentry)1545 int security_sb_statfs(struct dentry *dentry)
1546 {
1547 return call_int_hook(sb_statfs, dentry);
1548 }
1549
1550 /**
1551 * security_sb_mount() - Check permission for mounting a filesystem
1552 * @dev_name: filesystem backing device
1553 * @path: mount point
1554 * @type: filesystem type
1555 * @flags: mount flags
1556 * @data: filesystem specific data
1557 *
1558 * Check permission before an object specified by @dev_name is mounted on the
1559 * mount point named by @nd. For an ordinary mount, @dev_name identifies a
1560 * device if the file system type requires a device. For a remount
1561 * (@flags & MS_REMOUNT), @dev_name is irrelevant. For a loopback/bind mount
1562 * (@flags & MS_BIND), @dev_name identifies the pathname of the object being
1563 * mounted.
1564 *
1565 * Return: Returns 0 if permission is granted.
1566 */
security_sb_mount(const char * dev_name,const struct path * path,const char * type,unsigned long flags,void * data)1567 int security_sb_mount(const char *dev_name, const struct path *path,
1568 const char *type, unsigned long flags, void *data)
1569 {
1570 return call_int_hook(sb_mount, dev_name, path, type, flags, data);
1571 }
1572
1573 /**
1574 * security_sb_umount() - Check permission for unmounting a filesystem
1575 * @mnt: mounted filesystem
1576 * @flags: unmount flags
1577 *
1578 * Check permission before the @mnt file system is unmounted.
1579 *
1580 * Return: Returns 0 if permission is granted.
1581 */
security_sb_umount(struct vfsmount * mnt,int flags)1582 int security_sb_umount(struct vfsmount *mnt, int flags)
1583 {
1584 return call_int_hook(sb_umount, mnt, flags);
1585 }
1586
1587 /**
1588 * security_sb_pivotroot() - Check permissions for pivoting the rootfs
1589 * @old_path: new location for current rootfs
1590 * @new_path: location of the new rootfs
1591 *
1592 * Check permission before pivoting the root filesystem.
1593 *
1594 * Return: Returns 0 if permission is granted.
1595 */
security_sb_pivotroot(const struct path * old_path,const struct path * new_path)1596 int security_sb_pivotroot(const struct path *old_path,
1597 const struct path *new_path)
1598 {
1599 return call_int_hook(sb_pivotroot, old_path, new_path);
1600 }
1601
1602 /**
1603 * security_sb_set_mnt_opts() - Set the mount options for a filesystem
1604 * @sb: filesystem superblock
1605 * @mnt_opts: binary mount options
1606 * @kern_flags: kernel flags (in)
1607 * @set_kern_flags: kernel flags (out)
1608 *
1609 * Set the security relevant mount options used for a superblock.
1610 *
1611 * Return: Returns 0 on success, error on failure.
1612 */
security_sb_set_mnt_opts(struct super_block * sb,void * mnt_opts,unsigned long kern_flags,unsigned long * set_kern_flags)1613 int security_sb_set_mnt_opts(struct super_block *sb,
1614 void *mnt_opts,
1615 unsigned long kern_flags,
1616 unsigned long *set_kern_flags)
1617 {
1618 struct lsm_static_call *scall;
1619 int rc = mnt_opts ? -EOPNOTSUPP : LSM_RET_DEFAULT(sb_set_mnt_opts);
1620
1621 lsm_for_each_hook(scall, sb_set_mnt_opts) {
1622 rc = scall->hl->hook.sb_set_mnt_opts(sb, mnt_opts, kern_flags,
1623 set_kern_flags);
1624 if (rc != LSM_RET_DEFAULT(sb_set_mnt_opts))
1625 break;
1626 }
1627 return rc;
1628 }
1629 EXPORT_SYMBOL(security_sb_set_mnt_opts);
1630
1631 /**
1632 * security_sb_clone_mnt_opts() - Duplicate superblock mount options
1633 * @oldsb: source superblock
1634 * @newsb: destination superblock
1635 * @kern_flags: kernel flags (in)
1636 * @set_kern_flags: kernel flags (out)
1637 *
1638 * Copy all security options from a given superblock to another.
1639 *
1640 * Return: Returns 0 on success, error on failure.
1641 */
security_sb_clone_mnt_opts(const struct super_block * oldsb,struct super_block * newsb,unsigned long kern_flags,unsigned long * set_kern_flags)1642 int security_sb_clone_mnt_opts(const struct super_block *oldsb,
1643 struct super_block *newsb,
1644 unsigned long kern_flags,
1645 unsigned long *set_kern_flags)
1646 {
1647 return call_int_hook(sb_clone_mnt_opts, oldsb, newsb,
1648 kern_flags, set_kern_flags);
1649 }
1650 EXPORT_SYMBOL(security_sb_clone_mnt_opts);
1651
1652 /**
1653 * security_move_mount() - Check permissions for moving a mount
1654 * @from_path: source mount point
1655 * @to_path: destination mount point
1656 *
1657 * Check permission before a mount is moved.
1658 *
1659 * Return: Returns 0 if permission is granted.
1660 */
security_move_mount(const struct path * from_path,const struct path * to_path)1661 int security_move_mount(const struct path *from_path,
1662 const struct path *to_path)
1663 {
1664 return call_int_hook(move_mount, from_path, to_path);
1665 }
1666
1667 /**
1668 * security_path_notify() - Check if setting a watch is allowed
1669 * @path: file path
1670 * @mask: event mask
1671 * @obj_type: file path type
1672 *
1673 * Check permissions before setting a watch on events as defined by @mask, on
1674 * an object at @path, whose type is defined by @obj_type.
1675 *
1676 * Return: Returns 0 if permission is granted.
1677 */
security_path_notify(const struct path * path,u64 mask,unsigned int obj_type)1678 int security_path_notify(const struct path *path, u64 mask,
1679 unsigned int obj_type)
1680 {
1681 return call_int_hook(path_notify, path, mask, obj_type);
1682 }
1683
1684 /**
1685 * security_inode_alloc() - Allocate an inode LSM blob
1686 * @inode: the inode
1687 * @gfp: allocation flags
1688 *
1689 * Allocate and attach a security structure to @inode->i_security. The
1690 * i_security field is initialized to NULL when the inode structure is
1691 * allocated.
1692 *
1693 * Return: Return 0 if operation was successful.
1694 */
security_inode_alloc(struct inode * inode,gfp_t gfp)1695 int security_inode_alloc(struct inode *inode, gfp_t gfp)
1696 {
1697 int rc = lsm_inode_alloc(inode, gfp);
1698
1699 if (unlikely(rc))
1700 return rc;
1701 rc = call_int_hook(inode_alloc_security, inode);
1702 if (unlikely(rc))
1703 security_inode_free(inode);
1704 return rc;
1705 }
1706
inode_free_by_rcu(struct rcu_head * head)1707 static void inode_free_by_rcu(struct rcu_head *head)
1708 {
1709 /* The rcu head is at the start of the inode blob */
1710 call_void_hook(inode_free_security_rcu, head);
1711 kmem_cache_free(lsm_inode_cache, head);
1712 }
1713
1714 /**
1715 * security_inode_free() - Free an inode's LSM blob
1716 * @inode: the inode
1717 *
1718 * Release any LSM resources associated with @inode, although due to the
1719 * inode's RCU protections it is possible that the resources will not be
1720 * fully released until after the current RCU grace period has elapsed.
1721 *
1722 * It is important for LSMs to note that despite being present in a call to
1723 * security_inode_free(), @inode may still be referenced in a VFS path walk
1724 * and calls to security_inode_permission() may be made during, or after,
1725 * a call to security_inode_free(). For this reason the inode->i_security
1726 * field is released via a call_rcu() callback and any LSMs which need to
1727 * retain inode state for use in security_inode_permission() should only
1728 * release that state in the inode_free_security_rcu() LSM hook callback.
1729 */
security_inode_free(struct inode * inode)1730 void security_inode_free(struct inode *inode)
1731 {
1732 call_void_hook(inode_free_security, inode);
1733 if (!inode->i_security)
1734 return;
1735 call_rcu((struct rcu_head *)inode->i_security, inode_free_by_rcu);
1736 }
1737
1738 /**
1739 * security_dentry_init_security() - Perform dentry initialization
1740 * @dentry: the dentry to initialize
1741 * @mode: mode used to determine resource type
1742 * @name: name of the last path component
1743 * @xattr_name: name of the security/LSM xattr
1744 * @lsmctx: pointer to the resulting LSM context
1745 *
1746 * Compute a context for a dentry as the inode is not yet available since NFSv4
1747 * has no label backed by an EA anyway. It is important to note that
1748 * @xattr_name does not need to be free'd by the caller, it is a static string.
1749 *
1750 * Return: Returns 0 on success, negative values on failure.
1751 */
security_dentry_init_security(struct dentry * dentry,int mode,const struct qstr * name,const char ** xattr_name,struct lsm_context * lsmctx)1752 int security_dentry_init_security(struct dentry *dentry, int mode,
1753 const struct qstr *name,
1754 const char **xattr_name,
1755 struct lsm_context *lsmctx)
1756 {
1757 return call_int_hook(dentry_init_security, dentry, mode, name,
1758 xattr_name, lsmctx);
1759 }
1760 EXPORT_SYMBOL(security_dentry_init_security);
1761
1762 /**
1763 * security_dentry_create_files_as() - Perform dentry initialization
1764 * @dentry: the dentry to initialize
1765 * @mode: mode used to determine resource type
1766 * @name: name of the last path component
1767 * @old: creds to use for LSM context calculations
1768 * @new: creds to modify
1769 *
1770 * Compute a context for a dentry as the inode is not yet available and set
1771 * that context in passed in creds so that new files are created using that
1772 * context. Context is calculated using the passed in creds and not the creds
1773 * of the caller.
1774 *
1775 * Return: Returns 0 on success, error on failure.
1776 */
security_dentry_create_files_as(struct dentry * dentry,int mode,struct qstr * name,const struct cred * old,struct cred * new)1777 int security_dentry_create_files_as(struct dentry *dentry, int mode,
1778 struct qstr *name,
1779 const struct cred *old, struct cred *new)
1780 {
1781 return call_int_hook(dentry_create_files_as, dentry, mode,
1782 name, old, new);
1783 }
1784 EXPORT_SYMBOL(security_dentry_create_files_as);
1785
1786 /**
1787 * security_inode_init_security() - Initialize an inode's LSM context
1788 * @inode: the inode
1789 * @dir: parent directory
1790 * @qstr: last component of the pathname
1791 * @initxattrs: callback function to write xattrs
1792 * @fs_data: filesystem specific data
1793 *
1794 * Obtain the security attribute name suffix and value to set on a newly
1795 * created inode and set up the incore security field for the new inode. This
1796 * hook is called by the fs code as part of the inode creation transaction and
1797 * provides for atomic labeling of the inode, unlike the post_create/mkdir/...
1798 * hooks called by the VFS.
1799 *
1800 * The hook function is expected to populate the xattrs array, by calling
1801 * lsm_get_xattr_slot() to retrieve the slots reserved by the security module
1802 * with the lbs_xattr_count field of the lsm_blob_sizes structure. For each
1803 * slot, the hook function should set ->name to the attribute name suffix
1804 * (e.g. selinux), to allocate ->value (will be freed by the caller) and set it
1805 * to the attribute value, to set ->value_len to the length of the value. If
1806 * the security module does not use security attributes or does not wish to put
1807 * a security attribute on this particular inode, then it should return
1808 * -EOPNOTSUPP to skip this processing.
1809 *
1810 * Return: Returns 0 if the LSM successfully initialized all of the inode
1811 * security attributes that are required, negative values otherwise.
1812 */
security_inode_init_security(struct inode * inode,struct inode * dir,const struct qstr * qstr,const initxattrs initxattrs,void * fs_data)1813 int security_inode_init_security(struct inode *inode, struct inode *dir,
1814 const struct qstr *qstr,
1815 const initxattrs initxattrs, void *fs_data)
1816 {
1817 struct lsm_static_call *scall;
1818 struct xattr *new_xattrs = NULL;
1819 int ret = -EOPNOTSUPP, xattr_count = 0;
1820
1821 if (unlikely(IS_PRIVATE(inode)))
1822 return 0;
1823
1824 if (!blob_sizes.lbs_xattr_count)
1825 return 0;
1826
1827 if (initxattrs) {
1828 /* Allocate +1 as terminator. */
1829 new_xattrs = kcalloc(blob_sizes.lbs_xattr_count + 1,
1830 sizeof(*new_xattrs), GFP_NOFS);
1831 if (!new_xattrs)
1832 return -ENOMEM;
1833 }
1834
1835 lsm_for_each_hook(scall, inode_init_security) {
1836 ret = scall->hl->hook.inode_init_security(inode, dir, qstr, new_xattrs,
1837 &xattr_count);
1838 if (ret && ret != -EOPNOTSUPP)
1839 goto out;
1840 /*
1841 * As documented in lsm_hooks.h, -EOPNOTSUPP in this context
1842 * means that the LSM is not willing to provide an xattr, not
1843 * that it wants to signal an error. Thus, continue to invoke
1844 * the remaining LSMs.
1845 */
1846 }
1847
1848 /* If initxattrs() is NULL, xattr_count is zero, skip the call. */
1849 if (!xattr_count)
1850 goto out;
1851
1852 ret = initxattrs(inode, new_xattrs, fs_data);
1853 out:
1854 for (; xattr_count > 0; xattr_count--)
1855 kfree(new_xattrs[xattr_count - 1].value);
1856 kfree(new_xattrs);
1857 return (ret == -EOPNOTSUPP) ? 0 : ret;
1858 }
1859 EXPORT_SYMBOL(security_inode_init_security);
1860
1861 /**
1862 * security_inode_init_security_anon() - Initialize an anonymous inode
1863 * @inode: the inode
1864 * @name: the anonymous inode class
1865 * @context_inode: an optional related inode
1866 *
1867 * Set up the incore security field for the new anonymous inode and return
1868 * whether the inode creation is permitted by the security module or not.
1869 *
1870 * Return: Returns 0 on success, -EACCES if the security module denies the
1871 * creation of this inode, or another -errno upon other errors.
1872 */
security_inode_init_security_anon(struct inode * inode,const struct qstr * name,const struct inode * context_inode)1873 int security_inode_init_security_anon(struct inode *inode,
1874 const struct qstr *name,
1875 const struct inode *context_inode)
1876 {
1877 return call_int_hook(inode_init_security_anon, inode, name,
1878 context_inode);
1879 }
1880
1881 #ifdef CONFIG_SECURITY_PATH
1882 /**
1883 * security_path_mknod() - Check if creating a special file is allowed
1884 * @dir: parent directory
1885 * @dentry: new file
1886 * @mode: new file mode
1887 * @dev: device number
1888 *
1889 * Check permissions when creating a file. Note that this hook is called even
1890 * if mknod operation is being done for a regular file.
1891 *
1892 * Return: Returns 0 if permission is granted.
1893 */
security_path_mknod(const struct path * dir,struct dentry * dentry,umode_t mode,unsigned int dev)1894 int security_path_mknod(const struct path *dir, struct dentry *dentry,
1895 umode_t mode, unsigned int dev)
1896 {
1897 if (unlikely(IS_PRIVATE(d_backing_inode(dir->dentry))))
1898 return 0;
1899 return call_int_hook(path_mknod, dir, dentry, mode, dev);
1900 }
1901 EXPORT_SYMBOL(security_path_mknod);
1902
1903 /**
1904 * security_path_post_mknod() - Update inode security after reg file creation
1905 * @idmap: idmap of the mount
1906 * @dentry: new file
1907 *
1908 * Update inode security field after a regular file has been created.
1909 */
security_path_post_mknod(struct mnt_idmap * idmap,struct dentry * dentry)1910 void security_path_post_mknod(struct mnt_idmap *idmap, struct dentry *dentry)
1911 {
1912 if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
1913 return;
1914 call_void_hook(path_post_mknod, idmap, dentry);
1915 }
1916
1917 /**
1918 * security_path_mkdir() - Check if creating a new directory is allowed
1919 * @dir: parent directory
1920 * @dentry: new directory
1921 * @mode: new directory mode
1922 *
1923 * Check permissions to create a new directory in the existing directory.
1924 *
1925 * Return: Returns 0 if permission is granted.
1926 */
security_path_mkdir(const struct path * dir,struct dentry * dentry,umode_t mode)1927 int security_path_mkdir(const struct path *dir, struct dentry *dentry,
1928 umode_t mode)
1929 {
1930 if (unlikely(IS_PRIVATE(d_backing_inode(dir->dentry))))
1931 return 0;
1932 return call_int_hook(path_mkdir, dir, dentry, mode);
1933 }
1934 EXPORT_SYMBOL(security_path_mkdir);
1935
1936 /**
1937 * security_path_rmdir() - Check if removing a directory is allowed
1938 * @dir: parent directory
1939 * @dentry: directory to remove
1940 *
1941 * Check the permission to remove a directory.
1942 *
1943 * Return: Returns 0 if permission is granted.
1944 */
security_path_rmdir(const struct path * dir,struct dentry * dentry)1945 int security_path_rmdir(const struct path *dir, struct dentry *dentry)
1946 {
1947 if (unlikely(IS_PRIVATE(d_backing_inode(dir->dentry))))
1948 return 0;
1949 return call_int_hook(path_rmdir, dir, dentry);
1950 }
1951
1952 /**
1953 * security_path_unlink() - Check if removing a hard link is allowed
1954 * @dir: parent directory
1955 * @dentry: file
1956 *
1957 * Check the permission to remove a hard link to a file.
1958 *
1959 * Return: Returns 0 if permission is granted.
1960 */
security_path_unlink(const struct path * dir,struct dentry * dentry)1961 int security_path_unlink(const struct path *dir, struct dentry *dentry)
1962 {
1963 if (unlikely(IS_PRIVATE(d_backing_inode(dir->dentry))))
1964 return 0;
1965 return call_int_hook(path_unlink, dir, dentry);
1966 }
1967 EXPORT_SYMBOL(security_path_unlink);
1968
1969 /**
1970 * security_path_symlink() - Check if creating a symbolic link is allowed
1971 * @dir: parent directory
1972 * @dentry: symbolic link
1973 * @old_name: file pathname
1974 *
1975 * Check the permission to create a symbolic link to a file.
1976 *
1977 * Return: Returns 0 if permission is granted.
1978 */
security_path_symlink(const struct path * dir,struct dentry * dentry,const char * old_name)1979 int security_path_symlink(const struct path *dir, struct dentry *dentry,
1980 const char *old_name)
1981 {
1982 if (unlikely(IS_PRIVATE(d_backing_inode(dir->dentry))))
1983 return 0;
1984 return call_int_hook(path_symlink, dir, dentry, old_name);
1985 }
1986
1987 /**
1988 * security_path_link - Check if creating a hard link is allowed
1989 * @old_dentry: existing file
1990 * @new_dir: new parent directory
1991 * @new_dentry: new link
1992 *
1993 * Check permission before creating a new hard link to a file.
1994 *
1995 * Return: Returns 0 if permission is granted.
1996 */
security_path_link(struct dentry * old_dentry,const struct path * new_dir,struct dentry * new_dentry)1997 int security_path_link(struct dentry *old_dentry, const struct path *new_dir,
1998 struct dentry *new_dentry)
1999 {
2000 if (unlikely(IS_PRIVATE(d_backing_inode(old_dentry))))
2001 return 0;
2002 return call_int_hook(path_link, old_dentry, new_dir, new_dentry);
2003 }
2004
2005 /**
2006 * security_path_rename() - Check if renaming a file is allowed
2007 * @old_dir: parent directory of the old file
2008 * @old_dentry: the old file
2009 * @new_dir: parent directory of the new file
2010 * @new_dentry: the new file
2011 * @flags: flags
2012 *
2013 * Check for permission to rename a file or directory.
2014 *
2015 * Return: Returns 0 if permission is granted.
2016 */
security_path_rename(const struct path * old_dir,struct dentry * old_dentry,const struct path * new_dir,struct dentry * new_dentry,unsigned int flags)2017 int security_path_rename(const struct path *old_dir, struct dentry *old_dentry,
2018 const struct path *new_dir, struct dentry *new_dentry,
2019 unsigned int flags)
2020 {
2021 if (unlikely(IS_PRIVATE(d_backing_inode(old_dentry)) ||
2022 (d_is_positive(new_dentry) &&
2023 IS_PRIVATE(d_backing_inode(new_dentry)))))
2024 return 0;
2025
2026 return call_int_hook(path_rename, old_dir, old_dentry, new_dir,
2027 new_dentry, flags);
2028 }
2029 EXPORT_SYMBOL(security_path_rename);
2030
2031 /**
2032 * security_path_truncate() - Check if truncating a file is allowed
2033 * @path: file
2034 *
2035 * Check permission before truncating the file indicated by path. Note that
2036 * truncation permissions may also be checked based on already opened files,
2037 * using the security_file_truncate() hook.
2038 *
2039 * Return: Returns 0 if permission is granted.
2040 */
security_path_truncate(const struct path * path)2041 int security_path_truncate(const struct path *path)
2042 {
2043 if (unlikely(IS_PRIVATE(d_backing_inode(path->dentry))))
2044 return 0;
2045 return call_int_hook(path_truncate, path);
2046 }
2047
2048 /**
2049 * security_path_chmod() - Check if changing the file's mode is allowed
2050 * @path: file
2051 * @mode: new mode
2052 *
2053 * Check for permission to change a mode of the file @path. The new mode is
2054 * specified in @mode which is a bitmask of constants from
2055 * <include/uapi/linux/stat.h>.
2056 *
2057 * Return: Returns 0 if permission is granted.
2058 */
security_path_chmod(const struct path * path,umode_t mode)2059 int security_path_chmod(const struct path *path, umode_t mode)
2060 {
2061 if (unlikely(IS_PRIVATE(d_backing_inode(path->dentry))))
2062 return 0;
2063 return call_int_hook(path_chmod, path, mode);
2064 }
2065
2066 /**
2067 * security_path_chown() - Check if changing the file's owner/group is allowed
2068 * @path: file
2069 * @uid: file owner
2070 * @gid: file group
2071 *
2072 * Check for permission to change owner/group of a file or directory.
2073 *
2074 * Return: Returns 0 if permission is granted.
2075 */
security_path_chown(const struct path * path,kuid_t uid,kgid_t gid)2076 int security_path_chown(const struct path *path, kuid_t uid, kgid_t gid)
2077 {
2078 if (unlikely(IS_PRIVATE(d_backing_inode(path->dentry))))
2079 return 0;
2080 return call_int_hook(path_chown, path, uid, gid);
2081 }
2082
2083 /**
2084 * security_path_chroot() - Check if changing the root directory is allowed
2085 * @path: directory
2086 *
2087 * Check for permission to change root directory.
2088 *
2089 * Return: Returns 0 if permission is granted.
2090 */
security_path_chroot(const struct path * path)2091 int security_path_chroot(const struct path *path)
2092 {
2093 return call_int_hook(path_chroot, path);
2094 }
2095 #endif /* CONFIG_SECURITY_PATH */
2096
2097 /**
2098 * security_inode_create() - Check if creating a file is allowed
2099 * @dir: the parent directory
2100 * @dentry: the file being created
2101 * @mode: requested file mode
2102 *
2103 * Check permission to create a regular file.
2104 *
2105 * Return: Returns 0 if permission is granted.
2106 */
security_inode_create(struct inode * dir,struct dentry * dentry,umode_t mode)2107 int security_inode_create(struct inode *dir, struct dentry *dentry,
2108 umode_t mode)
2109 {
2110 if (unlikely(IS_PRIVATE(dir)))
2111 return 0;
2112 return call_int_hook(inode_create, dir, dentry, mode);
2113 }
2114 EXPORT_SYMBOL_GPL(security_inode_create);
2115
2116 /**
2117 * security_inode_post_create_tmpfile() - Update inode security of new tmpfile
2118 * @idmap: idmap of the mount
2119 * @inode: inode of the new tmpfile
2120 *
2121 * Update inode security data after a tmpfile has been created.
2122 */
security_inode_post_create_tmpfile(struct mnt_idmap * idmap,struct inode * inode)2123 void security_inode_post_create_tmpfile(struct mnt_idmap *idmap,
2124 struct inode *inode)
2125 {
2126 if (unlikely(IS_PRIVATE(inode)))
2127 return;
2128 call_void_hook(inode_post_create_tmpfile, idmap, inode);
2129 }
2130
2131 /**
2132 * security_inode_link() - Check if creating a hard link is allowed
2133 * @old_dentry: existing file
2134 * @dir: new parent directory
2135 * @new_dentry: new link
2136 *
2137 * Check permission before creating a new hard link to a file.
2138 *
2139 * Return: Returns 0 if permission is granted.
2140 */
security_inode_link(struct dentry * old_dentry,struct inode * dir,struct dentry * new_dentry)2141 int security_inode_link(struct dentry *old_dentry, struct inode *dir,
2142 struct dentry *new_dentry)
2143 {
2144 if (unlikely(IS_PRIVATE(d_backing_inode(old_dentry))))
2145 return 0;
2146 return call_int_hook(inode_link, old_dentry, dir, new_dentry);
2147 }
2148
2149 /**
2150 * security_inode_unlink() - Check if removing a hard link is allowed
2151 * @dir: parent directory
2152 * @dentry: file
2153 *
2154 * Check the permission to remove a hard link to a file.
2155 *
2156 * Return: Returns 0 if permission is granted.
2157 */
security_inode_unlink(struct inode * dir,struct dentry * dentry)2158 int security_inode_unlink(struct inode *dir, struct dentry *dentry)
2159 {
2160 if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
2161 return 0;
2162 return call_int_hook(inode_unlink, dir, dentry);
2163 }
2164
2165 /**
2166 * security_inode_symlink() - Check if creating a symbolic link is allowed
2167 * @dir: parent directory
2168 * @dentry: symbolic link
2169 * @old_name: existing filename
2170 *
2171 * Check the permission to create a symbolic link to a file.
2172 *
2173 * Return: Returns 0 if permission is granted.
2174 */
security_inode_symlink(struct inode * dir,struct dentry * dentry,const char * old_name)2175 int security_inode_symlink(struct inode *dir, struct dentry *dentry,
2176 const char *old_name)
2177 {
2178 if (unlikely(IS_PRIVATE(dir)))
2179 return 0;
2180 return call_int_hook(inode_symlink, dir, dentry, old_name);
2181 }
2182
2183 /**
2184 * security_inode_mkdir() - Check if creating a new directory is allowed
2185 * @dir: parent directory
2186 * @dentry: new directory
2187 * @mode: new directory mode
2188 *
2189 * Check permissions to create a new directory in the existing directory
2190 * associated with inode structure @dir.
2191 *
2192 * Return: Returns 0 if permission is granted.
2193 */
security_inode_mkdir(struct inode * dir,struct dentry * dentry,umode_t mode)2194 int security_inode_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
2195 {
2196 if (unlikely(IS_PRIVATE(dir)))
2197 return 0;
2198 return call_int_hook(inode_mkdir, dir, dentry, mode);
2199 }
2200 EXPORT_SYMBOL_GPL(security_inode_mkdir);
2201
2202 /**
2203 * security_inode_rmdir() - Check if removing a directory is allowed
2204 * @dir: parent directory
2205 * @dentry: directory to be removed
2206 *
2207 * Check the permission to remove a directory.
2208 *
2209 * Return: Returns 0 if permission is granted.
2210 */
security_inode_rmdir(struct inode * dir,struct dentry * dentry)2211 int security_inode_rmdir(struct inode *dir, struct dentry *dentry)
2212 {
2213 if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
2214 return 0;
2215 return call_int_hook(inode_rmdir, dir, dentry);
2216 }
2217
2218 /**
2219 * security_inode_mknod() - Check if creating a special file is allowed
2220 * @dir: parent directory
2221 * @dentry: new file
2222 * @mode: new file mode
2223 * @dev: device number
2224 *
2225 * Check permissions when creating a special file (or a socket or a fifo file
2226 * created via the mknod system call). Note that if mknod operation is being
2227 * done for a regular file, then the create hook will be called and not this
2228 * hook.
2229 *
2230 * Return: Returns 0 if permission is granted.
2231 */
security_inode_mknod(struct inode * dir,struct dentry * dentry,umode_t mode,dev_t dev)2232 int security_inode_mknod(struct inode *dir, struct dentry *dentry,
2233 umode_t mode, dev_t dev)
2234 {
2235 if (unlikely(IS_PRIVATE(dir)))
2236 return 0;
2237 return call_int_hook(inode_mknod, dir, dentry, mode, dev);
2238 }
2239
2240 /**
2241 * security_inode_rename() - Check if renaming a file is allowed
2242 * @old_dir: parent directory of the old file
2243 * @old_dentry: the old file
2244 * @new_dir: parent directory of the new file
2245 * @new_dentry: the new file
2246 * @flags: flags
2247 *
2248 * Check for permission to rename a file or directory.
2249 *
2250 * Return: Returns 0 if permission is granted.
2251 */
security_inode_rename(struct inode * old_dir,struct dentry * old_dentry,struct inode * new_dir,struct dentry * new_dentry,unsigned int flags)2252 int security_inode_rename(struct inode *old_dir, struct dentry *old_dentry,
2253 struct inode *new_dir, struct dentry *new_dentry,
2254 unsigned int flags)
2255 {
2256 if (unlikely(IS_PRIVATE(d_backing_inode(old_dentry)) ||
2257 (d_is_positive(new_dentry) &&
2258 IS_PRIVATE(d_backing_inode(new_dentry)))))
2259 return 0;
2260
2261 if (flags & RENAME_EXCHANGE) {
2262 int err = call_int_hook(inode_rename, new_dir, new_dentry,
2263 old_dir, old_dentry);
2264 if (err)
2265 return err;
2266 }
2267
2268 return call_int_hook(inode_rename, old_dir, old_dentry,
2269 new_dir, new_dentry);
2270 }
2271
2272 /**
2273 * security_inode_readlink() - Check if reading a symbolic link is allowed
2274 * @dentry: link
2275 *
2276 * Check the permission to read the symbolic link.
2277 *
2278 * Return: Returns 0 if permission is granted.
2279 */
security_inode_readlink(struct dentry * dentry)2280 int security_inode_readlink(struct dentry *dentry)
2281 {
2282 if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
2283 return 0;
2284 return call_int_hook(inode_readlink, dentry);
2285 }
2286
2287 /**
2288 * security_inode_follow_link() - Check if following a symbolic link is allowed
2289 * @dentry: link dentry
2290 * @inode: link inode
2291 * @rcu: true if in RCU-walk mode
2292 *
2293 * Check permission to follow a symbolic link when looking up a pathname. If
2294 * @rcu is true, @inode is not stable.
2295 *
2296 * Return: Returns 0 if permission is granted.
2297 */
security_inode_follow_link(struct dentry * dentry,struct inode * inode,bool rcu)2298 int security_inode_follow_link(struct dentry *dentry, struct inode *inode,
2299 bool rcu)
2300 {
2301 if (unlikely(IS_PRIVATE(inode)))
2302 return 0;
2303 return call_int_hook(inode_follow_link, dentry, inode, rcu);
2304 }
2305
2306 /**
2307 * security_inode_permission() - Check if accessing an inode is allowed
2308 * @inode: inode
2309 * @mask: access mask
2310 *
2311 * Check permission before accessing an inode. This hook is called by the
2312 * existing Linux permission function, so a security module can use it to
2313 * provide additional checking for existing Linux permission checks. Notice
2314 * that this hook is called when a file is opened (as well as many other
2315 * operations), whereas the file_security_ops permission hook is called when
2316 * the actual read/write operations are performed.
2317 *
2318 * Return: Returns 0 if permission is granted.
2319 */
security_inode_permission(struct inode * inode,int mask)2320 int security_inode_permission(struct inode *inode, int mask)
2321 {
2322 if (unlikely(IS_PRIVATE(inode)))
2323 return 0;
2324 return call_int_hook(inode_permission, inode, mask);
2325 }
2326
2327 /**
2328 * security_inode_setattr() - Check if setting file attributes is allowed
2329 * @idmap: idmap of the mount
2330 * @dentry: file
2331 * @attr: new attributes
2332 *
2333 * Check permission before setting file attributes. Note that the kernel call
2334 * to notify_change is performed from several locations, whenever file
2335 * attributes change (such as when a file is truncated, chown/chmod operations,
2336 * transferring disk quotas, etc).
2337 *
2338 * Return: Returns 0 if permission is granted.
2339 */
security_inode_setattr(struct mnt_idmap * idmap,struct dentry * dentry,struct iattr * attr)2340 int security_inode_setattr(struct mnt_idmap *idmap,
2341 struct dentry *dentry, struct iattr *attr)
2342 {
2343 if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
2344 return 0;
2345 return call_int_hook(inode_setattr, idmap, dentry, attr);
2346 }
2347 EXPORT_SYMBOL_GPL(security_inode_setattr);
2348
2349 /**
2350 * security_inode_post_setattr() - Update the inode after a setattr operation
2351 * @idmap: idmap of the mount
2352 * @dentry: file
2353 * @ia_valid: file attributes set
2354 *
2355 * Update inode security field after successful setting file attributes.
2356 */
security_inode_post_setattr(struct mnt_idmap * idmap,struct dentry * dentry,int ia_valid)2357 void security_inode_post_setattr(struct mnt_idmap *idmap, struct dentry *dentry,
2358 int ia_valid)
2359 {
2360 if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
2361 return;
2362 call_void_hook(inode_post_setattr, idmap, dentry, ia_valid);
2363 }
2364
2365 /**
2366 * security_inode_getattr() - Check if getting file attributes is allowed
2367 * @path: file
2368 *
2369 * Check permission before obtaining file attributes.
2370 *
2371 * Return: Returns 0 if permission is granted.
2372 */
security_inode_getattr(const struct path * path)2373 int security_inode_getattr(const struct path *path)
2374 {
2375 if (unlikely(IS_PRIVATE(d_backing_inode(path->dentry))))
2376 return 0;
2377 return call_int_hook(inode_getattr, path);
2378 }
2379
2380 /**
2381 * security_inode_setxattr() - Check if setting file xattrs is allowed
2382 * @idmap: idmap of the mount
2383 * @dentry: file
2384 * @name: xattr name
2385 * @value: xattr value
2386 * @size: size of xattr value
2387 * @flags: flags
2388 *
2389 * This hook performs the desired permission checks before setting the extended
2390 * attributes (xattrs) on @dentry. It is important to note that we have some
2391 * additional logic before the main LSM implementation calls to detect if we
2392 * need to perform an additional capability check at the LSM layer.
2393 *
2394 * Normally we enforce a capability check prior to executing the various LSM
2395 * hook implementations, but if a LSM wants to avoid this capability check,
2396 * it can register a 'inode_xattr_skipcap' hook and return a value of 1 for
2397 * xattrs that it wants to avoid the capability check, leaving the LSM fully
2398 * responsible for enforcing the access control for the specific xattr. If all
2399 * of the enabled LSMs refrain from registering a 'inode_xattr_skipcap' hook,
2400 * or return a 0 (the default return value), the capability check is still
2401 * performed. If no 'inode_xattr_skipcap' hooks are registered the capability
2402 * check is performed.
2403 *
2404 * Return: Returns 0 if permission is granted.
2405 */
security_inode_setxattr(struct mnt_idmap * idmap,struct dentry * dentry,const char * name,const void * value,size_t size,int flags)2406 int security_inode_setxattr(struct mnt_idmap *idmap,
2407 struct dentry *dentry, const char *name,
2408 const void *value, size_t size, int flags)
2409 {
2410 int rc;
2411
2412 if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
2413 return 0;
2414
2415 /* enforce the capability checks at the lsm layer, if needed */
2416 if (!call_int_hook(inode_xattr_skipcap, name)) {
2417 rc = cap_inode_setxattr(dentry, name, value, size, flags);
2418 if (rc)
2419 return rc;
2420 }
2421
2422 return call_int_hook(inode_setxattr, idmap, dentry, name, value, size,
2423 flags);
2424 }
2425
2426 /**
2427 * security_inode_set_acl() - Check if setting posix acls is allowed
2428 * @idmap: idmap of the mount
2429 * @dentry: file
2430 * @acl_name: acl name
2431 * @kacl: acl struct
2432 *
2433 * Check permission before setting posix acls, the posix acls in @kacl are
2434 * identified by @acl_name.
2435 *
2436 * Return: Returns 0 if permission is granted.
2437 */
security_inode_set_acl(struct mnt_idmap * idmap,struct dentry * dentry,const char * acl_name,struct posix_acl * kacl)2438 int security_inode_set_acl(struct mnt_idmap *idmap,
2439 struct dentry *dentry, const char *acl_name,
2440 struct posix_acl *kacl)
2441 {
2442 if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
2443 return 0;
2444 return call_int_hook(inode_set_acl, idmap, dentry, acl_name, kacl);
2445 }
2446
2447 /**
2448 * security_inode_post_set_acl() - Update inode security from posix acls set
2449 * @dentry: file
2450 * @acl_name: acl name
2451 * @kacl: acl struct
2452 *
2453 * Update inode security data after successfully setting posix acls on @dentry.
2454 * The posix acls in @kacl are identified by @acl_name.
2455 */
security_inode_post_set_acl(struct dentry * dentry,const char * acl_name,struct posix_acl * kacl)2456 void security_inode_post_set_acl(struct dentry *dentry, const char *acl_name,
2457 struct posix_acl *kacl)
2458 {
2459 if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
2460 return;
2461 call_void_hook(inode_post_set_acl, dentry, acl_name, kacl);
2462 }
2463
2464 /**
2465 * security_inode_get_acl() - Check if reading posix acls is allowed
2466 * @idmap: idmap of the mount
2467 * @dentry: file
2468 * @acl_name: acl name
2469 *
2470 * Check permission before getting osix acls, the posix acls are identified by
2471 * @acl_name.
2472 *
2473 * Return: Returns 0 if permission is granted.
2474 */
security_inode_get_acl(struct mnt_idmap * idmap,struct dentry * dentry,const char * acl_name)2475 int security_inode_get_acl(struct mnt_idmap *idmap,
2476 struct dentry *dentry, const char *acl_name)
2477 {
2478 if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
2479 return 0;
2480 return call_int_hook(inode_get_acl, idmap, dentry, acl_name);
2481 }
2482
2483 /**
2484 * security_inode_remove_acl() - Check if removing a posix acl is allowed
2485 * @idmap: idmap of the mount
2486 * @dentry: file
2487 * @acl_name: acl name
2488 *
2489 * Check permission before removing posix acls, the posix acls are identified
2490 * by @acl_name.
2491 *
2492 * Return: Returns 0 if permission is granted.
2493 */
security_inode_remove_acl(struct mnt_idmap * idmap,struct dentry * dentry,const char * acl_name)2494 int security_inode_remove_acl(struct mnt_idmap *idmap,
2495 struct dentry *dentry, const char *acl_name)
2496 {
2497 if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
2498 return 0;
2499 return call_int_hook(inode_remove_acl, idmap, dentry, acl_name);
2500 }
2501
2502 /**
2503 * security_inode_post_remove_acl() - Update inode security after rm posix acls
2504 * @idmap: idmap of the mount
2505 * @dentry: file
2506 * @acl_name: acl name
2507 *
2508 * Update inode security data after successfully removing posix acls on
2509 * @dentry in @idmap. The posix acls are identified by @acl_name.
2510 */
security_inode_post_remove_acl(struct mnt_idmap * idmap,struct dentry * dentry,const char * acl_name)2511 void security_inode_post_remove_acl(struct mnt_idmap *idmap,
2512 struct dentry *dentry, const char *acl_name)
2513 {
2514 if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
2515 return;
2516 call_void_hook(inode_post_remove_acl, idmap, dentry, acl_name);
2517 }
2518
2519 /**
2520 * security_inode_post_setxattr() - Update the inode after a setxattr operation
2521 * @dentry: file
2522 * @name: xattr name
2523 * @value: xattr value
2524 * @size: xattr value size
2525 * @flags: flags
2526 *
2527 * Update inode security field after successful setxattr operation.
2528 */
security_inode_post_setxattr(struct dentry * dentry,const char * name,const void * value,size_t size,int flags)2529 void security_inode_post_setxattr(struct dentry *dentry, const char *name,
2530 const void *value, size_t size, int flags)
2531 {
2532 if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
2533 return;
2534 call_void_hook(inode_post_setxattr, dentry, name, value, size, flags);
2535 }
2536
2537 /**
2538 * security_inode_getxattr() - Check if xattr access is allowed
2539 * @dentry: file
2540 * @name: xattr name
2541 *
2542 * Check permission before obtaining the extended attributes identified by
2543 * @name for @dentry.
2544 *
2545 * Return: Returns 0 if permission is granted.
2546 */
security_inode_getxattr(struct dentry * dentry,const char * name)2547 int security_inode_getxattr(struct dentry *dentry, const char *name)
2548 {
2549 if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
2550 return 0;
2551 return call_int_hook(inode_getxattr, dentry, name);
2552 }
2553
2554 /**
2555 * security_inode_listxattr() - Check if listing xattrs is allowed
2556 * @dentry: file
2557 *
2558 * Check permission before obtaining the list of extended attribute names for
2559 * @dentry.
2560 *
2561 * Return: Returns 0 if permission is granted.
2562 */
security_inode_listxattr(struct dentry * dentry)2563 int security_inode_listxattr(struct dentry *dentry)
2564 {
2565 if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
2566 return 0;
2567 return call_int_hook(inode_listxattr, dentry);
2568 }
2569
2570 /**
2571 * security_inode_removexattr() - Check if removing an xattr is allowed
2572 * @idmap: idmap of the mount
2573 * @dentry: file
2574 * @name: xattr name
2575 *
2576 * This hook performs the desired permission checks before setting the extended
2577 * attributes (xattrs) on @dentry. It is important to note that we have some
2578 * additional logic before the main LSM implementation calls to detect if we
2579 * need to perform an additional capability check at the LSM layer.
2580 *
2581 * Normally we enforce a capability check prior to executing the various LSM
2582 * hook implementations, but if a LSM wants to avoid this capability check,
2583 * it can register a 'inode_xattr_skipcap' hook and return a value of 1 for
2584 * xattrs that it wants to avoid the capability check, leaving the LSM fully
2585 * responsible for enforcing the access control for the specific xattr. If all
2586 * of the enabled LSMs refrain from registering a 'inode_xattr_skipcap' hook,
2587 * or return a 0 (the default return value), the capability check is still
2588 * performed. If no 'inode_xattr_skipcap' hooks are registered the capability
2589 * check is performed.
2590 *
2591 * Return: Returns 0 if permission is granted.
2592 */
security_inode_removexattr(struct mnt_idmap * idmap,struct dentry * dentry,const char * name)2593 int security_inode_removexattr(struct mnt_idmap *idmap,
2594 struct dentry *dentry, const char *name)
2595 {
2596 int rc;
2597
2598 if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
2599 return 0;
2600
2601 /* enforce the capability checks at the lsm layer, if needed */
2602 if (!call_int_hook(inode_xattr_skipcap, name)) {
2603 rc = cap_inode_removexattr(idmap, dentry, name);
2604 if (rc)
2605 return rc;
2606 }
2607
2608 return call_int_hook(inode_removexattr, idmap, dentry, name);
2609 }
2610
2611 /**
2612 * security_inode_post_removexattr() - Update the inode after a removexattr op
2613 * @dentry: file
2614 * @name: xattr name
2615 *
2616 * Update the inode after a successful removexattr operation.
2617 */
security_inode_post_removexattr(struct dentry * dentry,const char * name)2618 void security_inode_post_removexattr(struct dentry *dentry, const char *name)
2619 {
2620 if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
2621 return;
2622 call_void_hook(inode_post_removexattr, dentry, name);
2623 }
2624
2625 /**
2626 * security_inode_file_setattr() - check if setting fsxattr is allowed
2627 * @dentry: file to set filesystem extended attributes on
2628 * @fa: extended attributes to set on the inode
2629 *
2630 * Called when file_setattr() syscall or FS_IOC_FSSETXATTR ioctl() is called on
2631 * inode
2632 *
2633 * Return: Returns 0 if permission is granted.
2634 */
security_inode_file_setattr(struct dentry * dentry,struct file_kattr * fa)2635 int security_inode_file_setattr(struct dentry *dentry, struct file_kattr *fa)
2636 {
2637 return call_int_hook(inode_file_setattr, dentry, fa);
2638 }
2639
2640 /**
2641 * security_inode_file_getattr() - check if retrieving fsxattr is allowed
2642 * @dentry: file to retrieve filesystem extended attributes from
2643 * @fa: extended attributes to get
2644 *
2645 * Called when file_getattr() syscall or FS_IOC_FSGETXATTR ioctl() is called on
2646 * inode
2647 *
2648 * Return: Returns 0 if permission is granted.
2649 */
security_inode_file_getattr(struct dentry * dentry,struct file_kattr * fa)2650 int security_inode_file_getattr(struct dentry *dentry, struct file_kattr *fa)
2651 {
2652 return call_int_hook(inode_file_getattr, dentry, fa);
2653 }
2654
2655 /**
2656 * security_inode_need_killpriv() - Check if security_inode_killpriv() required
2657 * @dentry: associated dentry
2658 *
2659 * Called when an inode has been changed to determine if
2660 * security_inode_killpriv() should be called.
2661 *
2662 * Return: Return <0 on error to abort the inode change operation, return 0 if
2663 * security_inode_killpriv() does not need to be called, return >0 if
2664 * security_inode_killpriv() does need to be called.
2665 */
security_inode_need_killpriv(struct dentry * dentry)2666 int security_inode_need_killpriv(struct dentry *dentry)
2667 {
2668 return call_int_hook(inode_need_killpriv, dentry);
2669 }
2670
2671 /**
2672 * security_inode_killpriv() - The setuid bit is removed, update LSM state
2673 * @idmap: idmap of the mount
2674 * @dentry: associated dentry
2675 *
2676 * The @dentry's setuid bit is being removed. Remove similar security labels.
2677 * Called with the dentry->d_inode->i_mutex held.
2678 *
2679 * Return: Return 0 on success. If error is returned, then the operation
2680 * causing setuid bit removal is failed.
2681 */
security_inode_killpriv(struct mnt_idmap * idmap,struct dentry * dentry)2682 int security_inode_killpriv(struct mnt_idmap *idmap,
2683 struct dentry *dentry)
2684 {
2685 return call_int_hook(inode_killpriv, idmap, dentry);
2686 }
2687
2688 /**
2689 * security_inode_getsecurity() - Get the xattr security label of an inode
2690 * @idmap: idmap of the mount
2691 * @inode: inode
2692 * @name: xattr name
2693 * @buffer: security label buffer
2694 * @alloc: allocation flag
2695 *
2696 * Retrieve a copy of the extended attribute representation of the security
2697 * label associated with @name for @inode via @buffer. Note that @name is the
2698 * remainder of the attribute name after the security prefix has been removed.
2699 * @alloc is used to specify if the call should return a value via the buffer
2700 * or just the value length.
2701 *
2702 * Return: Returns size of buffer on success.
2703 */
security_inode_getsecurity(struct mnt_idmap * idmap,struct inode * inode,const char * name,void ** buffer,bool alloc)2704 int security_inode_getsecurity(struct mnt_idmap *idmap,
2705 struct inode *inode, const char *name,
2706 void **buffer, bool alloc)
2707 {
2708 if (unlikely(IS_PRIVATE(inode)))
2709 return LSM_RET_DEFAULT(inode_getsecurity);
2710
2711 return call_int_hook(inode_getsecurity, idmap, inode, name, buffer,
2712 alloc);
2713 }
2714
2715 /**
2716 * security_inode_setsecurity() - Set the xattr security label of an inode
2717 * @inode: inode
2718 * @name: xattr name
2719 * @value: security label
2720 * @size: length of security label
2721 * @flags: flags
2722 *
2723 * Set the security label associated with @name for @inode from the extended
2724 * attribute value @value. @size indicates the size of the @value in bytes.
2725 * @flags may be XATTR_CREATE, XATTR_REPLACE, or 0. Note that @name is the
2726 * remainder of the attribute name after the security. prefix has been removed.
2727 *
2728 * Return: Returns 0 on success.
2729 */
security_inode_setsecurity(struct inode * inode,const char * name,const void * value,size_t size,int flags)2730 int security_inode_setsecurity(struct inode *inode, const char *name,
2731 const void *value, size_t size, int flags)
2732 {
2733 if (unlikely(IS_PRIVATE(inode)))
2734 return LSM_RET_DEFAULT(inode_setsecurity);
2735
2736 return call_int_hook(inode_setsecurity, inode, name, value, size,
2737 flags);
2738 }
2739
2740 /**
2741 * security_inode_listsecurity() - List the xattr security label names
2742 * @inode: inode
2743 * @buffer: buffer
2744 * @buffer_size: size of buffer
2745 *
2746 * Copy the extended attribute names for the security labels associated with
2747 * @inode into @buffer. The maximum size of @buffer is specified by
2748 * @buffer_size. @buffer may be NULL to request the size of the buffer
2749 * required.
2750 *
2751 * Return: Returns number of bytes used/required on success.
2752 */
security_inode_listsecurity(struct inode * inode,char * buffer,size_t buffer_size)2753 int security_inode_listsecurity(struct inode *inode,
2754 char *buffer, size_t buffer_size)
2755 {
2756 if (unlikely(IS_PRIVATE(inode)))
2757 return 0;
2758 return call_int_hook(inode_listsecurity, inode, buffer, buffer_size);
2759 }
2760 EXPORT_SYMBOL(security_inode_listsecurity);
2761
2762 /**
2763 * security_inode_getlsmprop() - Get an inode's LSM data
2764 * @inode: inode
2765 * @prop: lsm specific information to return
2766 *
2767 * Get the lsm specific information associated with the node.
2768 */
security_inode_getlsmprop(struct inode * inode,struct lsm_prop * prop)2769 void security_inode_getlsmprop(struct inode *inode, struct lsm_prop *prop)
2770 {
2771 call_void_hook(inode_getlsmprop, inode, prop);
2772 }
2773
2774 /**
2775 * security_inode_copy_up() - Create new creds for an overlayfs copy-up op
2776 * @src: union dentry of copy-up file
2777 * @new: newly created creds
2778 *
2779 * A file is about to be copied up from lower layer to upper layer of overlay
2780 * filesystem. Security module can prepare a set of new creds and modify as
2781 * need be and return new creds. Caller will switch to new creds temporarily to
2782 * create new file and release newly allocated creds.
2783 *
2784 * Return: Returns 0 on success or a negative error code on error.
2785 */
security_inode_copy_up(struct dentry * src,struct cred ** new)2786 int security_inode_copy_up(struct dentry *src, struct cred **new)
2787 {
2788 return call_int_hook(inode_copy_up, src, new);
2789 }
2790 EXPORT_SYMBOL(security_inode_copy_up);
2791
2792 /**
2793 * security_inode_copy_up_xattr() - Filter xattrs in an overlayfs copy-up op
2794 * @src: union dentry of copy-up file
2795 * @name: xattr name
2796 *
2797 * Filter the xattrs being copied up when a unioned file is copied up from a
2798 * lower layer to the union/overlay layer. The caller is responsible for
2799 * reading and writing the xattrs, this hook is merely a filter.
2800 *
2801 * Return: Returns 0 to accept the xattr, -ECANCELED to discard the xattr,
2802 * -EOPNOTSUPP if the security module does not know about attribute,
2803 * or a negative error code to abort the copy up.
2804 */
security_inode_copy_up_xattr(struct dentry * src,const char * name)2805 int security_inode_copy_up_xattr(struct dentry *src, const char *name)
2806 {
2807 int rc;
2808
2809 rc = call_int_hook(inode_copy_up_xattr, src, name);
2810 if (rc != LSM_RET_DEFAULT(inode_copy_up_xattr))
2811 return rc;
2812
2813 return LSM_RET_DEFAULT(inode_copy_up_xattr);
2814 }
2815 EXPORT_SYMBOL(security_inode_copy_up_xattr);
2816
2817 /**
2818 * security_inode_setintegrity() - Set the inode's integrity data
2819 * @inode: inode
2820 * @type: type of integrity, e.g. hash digest, signature, etc
2821 * @value: the integrity value
2822 * @size: size of the integrity value
2823 *
2824 * Register a verified integrity measurement of a inode with LSMs.
2825 * LSMs should free the previously saved data if @value is NULL.
2826 *
2827 * Return: Returns 0 on success, negative values on failure.
2828 */
security_inode_setintegrity(const struct inode * inode,enum lsm_integrity_type type,const void * value,size_t size)2829 int security_inode_setintegrity(const struct inode *inode,
2830 enum lsm_integrity_type type, const void *value,
2831 size_t size)
2832 {
2833 return call_int_hook(inode_setintegrity, inode, type, value, size);
2834 }
2835 EXPORT_SYMBOL(security_inode_setintegrity);
2836
2837 /**
2838 * security_kernfs_init_security() - Init LSM context for a kernfs node
2839 * @kn_dir: parent kernfs node
2840 * @kn: the kernfs node to initialize
2841 *
2842 * Initialize the security context of a newly created kernfs node based on its
2843 * own and its parent's attributes.
2844 *
2845 * Return: Returns 0 if permission is granted.
2846 */
security_kernfs_init_security(struct kernfs_node * kn_dir,struct kernfs_node * kn)2847 int security_kernfs_init_security(struct kernfs_node *kn_dir,
2848 struct kernfs_node *kn)
2849 {
2850 return call_int_hook(kernfs_init_security, kn_dir, kn);
2851 }
2852
2853 /**
2854 * security_file_permission() - Check file permissions
2855 * @file: file
2856 * @mask: requested permissions
2857 *
2858 * Check file permissions before accessing an open file. This hook is called
2859 * by various operations that read or write files. A security module can use
2860 * this hook to perform additional checking on these operations, e.g. to
2861 * revalidate permissions on use to support privilege bracketing or policy
2862 * changes. Notice that this hook is used when the actual read/write
2863 * operations are performed, whereas the inode_security_ops hook is called when
2864 * a file is opened (as well as many other operations). Although this hook can
2865 * be used to revalidate permissions for various system call operations that
2866 * read or write files, it does not address the revalidation of permissions for
2867 * memory-mapped files. Security modules must handle this separately if they
2868 * need such revalidation.
2869 *
2870 * Return: Returns 0 if permission is granted.
2871 */
security_file_permission(struct file * file,int mask)2872 int security_file_permission(struct file *file, int mask)
2873 {
2874 return call_int_hook(file_permission, file, mask);
2875 }
2876
2877 /**
2878 * security_file_alloc() - Allocate and init a file's LSM blob
2879 * @file: the file
2880 *
2881 * Allocate and attach a security structure to the file->f_security field. The
2882 * security field is initialized to NULL when the structure is first created.
2883 *
2884 * Return: Return 0 if the hook is successful and permission is granted.
2885 */
security_file_alloc(struct file * file)2886 int security_file_alloc(struct file *file)
2887 {
2888 int rc = lsm_file_alloc(file);
2889
2890 if (rc)
2891 return rc;
2892 rc = call_int_hook(file_alloc_security, file);
2893 if (unlikely(rc))
2894 security_file_free(file);
2895 return rc;
2896 }
2897
2898 /**
2899 * security_file_release() - Perform actions before releasing the file ref
2900 * @file: the file
2901 *
2902 * Perform actions before releasing the last reference to a file.
2903 */
security_file_release(struct file * file)2904 void security_file_release(struct file *file)
2905 {
2906 call_void_hook(file_release, file);
2907 }
2908
2909 /**
2910 * security_file_free() - Free a file's LSM blob
2911 * @file: the file
2912 *
2913 * Deallocate and free any security structures stored in file->f_security.
2914 */
security_file_free(struct file * file)2915 void security_file_free(struct file *file)
2916 {
2917 void *blob;
2918
2919 call_void_hook(file_free_security, file);
2920
2921 blob = file->f_security;
2922 if (blob) {
2923 file->f_security = NULL;
2924 kmem_cache_free(lsm_file_cache, blob);
2925 }
2926 }
2927
2928 /**
2929 * security_file_ioctl() - Check if an ioctl is allowed
2930 * @file: associated file
2931 * @cmd: ioctl cmd
2932 * @arg: ioctl arguments
2933 *
2934 * Check permission for an ioctl operation on @file. Note that @arg sometimes
2935 * represents a user space pointer; in other cases, it may be a simple integer
2936 * value. When @arg represents a user space pointer, it should never be used
2937 * by the security module.
2938 *
2939 * Return: Returns 0 if permission is granted.
2940 */
security_file_ioctl(struct file * file,unsigned int cmd,unsigned long arg)2941 int security_file_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
2942 {
2943 return call_int_hook(file_ioctl, file, cmd, arg);
2944 }
2945 EXPORT_SYMBOL_GPL(security_file_ioctl);
2946
2947 /**
2948 * security_file_ioctl_compat() - Check if an ioctl is allowed in compat mode
2949 * @file: associated file
2950 * @cmd: ioctl cmd
2951 * @arg: ioctl arguments
2952 *
2953 * Compat version of security_file_ioctl() that correctly handles 32-bit
2954 * processes running on 64-bit kernels.
2955 *
2956 * Return: Returns 0 if permission is granted.
2957 */
security_file_ioctl_compat(struct file * file,unsigned int cmd,unsigned long arg)2958 int security_file_ioctl_compat(struct file *file, unsigned int cmd,
2959 unsigned long arg)
2960 {
2961 return call_int_hook(file_ioctl_compat, file, cmd, arg);
2962 }
2963 EXPORT_SYMBOL_GPL(security_file_ioctl_compat);
2964
mmap_prot(struct file * file,unsigned long prot)2965 static inline unsigned long mmap_prot(struct file *file, unsigned long prot)
2966 {
2967 /*
2968 * Does we have PROT_READ and does the application expect
2969 * it to imply PROT_EXEC? If not, nothing to talk about...
2970 */
2971 if ((prot & (PROT_READ | PROT_EXEC)) != PROT_READ)
2972 return prot;
2973 if (!(current->personality & READ_IMPLIES_EXEC))
2974 return prot;
2975 /*
2976 * if that's an anonymous mapping, let it.
2977 */
2978 if (!file)
2979 return prot | PROT_EXEC;
2980 /*
2981 * ditto if it's not on noexec mount, except that on !MMU we need
2982 * NOMMU_MAP_EXEC (== VM_MAYEXEC) in this case
2983 */
2984 if (!path_noexec(&file->f_path)) {
2985 #ifndef CONFIG_MMU
2986 if (file->f_op->mmap_capabilities) {
2987 unsigned caps = file->f_op->mmap_capabilities(file);
2988 if (!(caps & NOMMU_MAP_EXEC))
2989 return prot;
2990 }
2991 #endif
2992 return prot | PROT_EXEC;
2993 }
2994 /* anything on noexec mount won't get PROT_EXEC */
2995 return prot;
2996 }
2997
2998 /**
2999 * security_mmap_file() - Check if mmap'ing a file is allowed
3000 * @file: file
3001 * @prot: protection applied by the kernel
3002 * @flags: flags
3003 *
3004 * Check permissions for a mmap operation. The @file may be NULL, e.g. if
3005 * mapping anonymous memory.
3006 *
3007 * Return: Returns 0 if permission is granted.
3008 */
security_mmap_file(struct file * file,unsigned long prot,unsigned long flags)3009 int security_mmap_file(struct file *file, unsigned long prot,
3010 unsigned long flags)
3011 {
3012 return call_int_hook(mmap_file, file, prot, mmap_prot(file, prot),
3013 flags);
3014 }
3015
3016 /**
3017 * security_mmap_addr() - Check if mmap'ing an address is allowed
3018 * @addr: address
3019 *
3020 * Check permissions for a mmap operation at @addr.
3021 *
3022 * Return: Returns 0 if permission is granted.
3023 */
security_mmap_addr(unsigned long addr)3024 int security_mmap_addr(unsigned long addr)
3025 {
3026 return call_int_hook(mmap_addr, addr);
3027 }
3028
3029 /**
3030 * security_file_mprotect() - Check if changing memory protections is allowed
3031 * @vma: memory region
3032 * @reqprot: application requested protection
3033 * @prot: protection applied by the kernel
3034 *
3035 * Check permissions before changing memory access permissions.
3036 *
3037 * Return: Returns 0 if permission is granted.
3038 */
security_file_mprotect(struct vm_area_struct * vma,unsigned long reqprot,unsigned long prot)3039 int security_file_mprotect(struct vm_area_struct *vma, unsigned long reqprot,
3040 unsigned long prot)
3041 {
3042 return call_int_hook(file_mprotect, vma, reqprot, prot);
3043 }
3044
3045 /**
3046 * security_file_lock() - Check if a file lock is allowed
3047 * @file: file
3048 * @cmd: lock operation (e.g. F_RDLCK, F_WRLCK)
3049 *
3050 * Check permission before performing file locking operations. Note the hook
3051 * mediates both flock and fcntl style locks.
3052 *
3053 * Return: Returns 0 if permission is granted.
3054 */
security_file_lock(struct file * file,unsigned int cmd)3055 int security_file_lock(struct file *file, unsigned int cmd)
3056 {
3057 return call_int_hook(file_lock, file, cmd);
3058 }
3059
3060 /**
3061 * security_file_fcntl() - Check if fcntl() op is allowed
3062 * @file: file
3063 * @cmd: fcntl command
3064 * @arg: command argument
3065 *
3066 * Check permission before allowing the file operation specified by @cmd from
3067 * being performed on the file @file. Note that @arg sometimes represents a
3068 * user space pointer; in other cases, it may be a simple integer value. When
3069 * @arg represents a user space pointer, it should never be used by the
3070 * security module.
3071 *
3072 * Return: Returns 0 if permission is granted.
3073 */
security_file_fcntl(struct file * file,unsigned int cmd,unsigned long arg)3074 int security_file_fcntl(struct file *file, unsigned int cmd, unsigned long arg)
3075 {
3076 return call_int_hook(file_fcntl, file, cmd, arg);
3077 }
3078
3079 /**
3080 * security_file_set_fowner() - Set the file owner info in the LSM blob
3081 * @file: the file
3082 *
3083 * Save owner security information (typically from current->security) in
3084 * file->f_security for later use by the send_sigiotask hook.
3085 *
3086 * This hook is called with file->f_owner.lock held.
3087 *
3088 * Return: Returns 0 on success.
3089 */
security_file_set_fowner(struct file * file)3090 void security_file_set_fowner(struct file *file)
3091 {
3092 call_void_hook(file_set_fowner, file);
3093 }
3094
3095 /**
3096 * security_file_send_sigiotask() - Check if sending SIGIO/SIGURG is allowed
3097 * @tsk: target task
3098 * @fown: signal sender
3099 * @sig: signal to be sent, SIGIO is sent if 0
3100 *
3101 * Check permission for the file owner @fown to send SIGIO or SIGURG to the
3102 * process @tsk. Note that this hook is sometimes called from interrupt. Note
3103 * that the fown_struct, @fown, is never outside the context of a struct file,
3104 * so the file structure (and associated security information) can always be
3105 * obtained: container_of(fown, struct file, f_owner).
3106 *
3107 * Return: Returns 0 if permission is granted.
3108 */
security_file_send_sigiotask(struct task_struct * tsk,struct fown_struct * fown,int sig)3109 int security_file_send_sigiotask(struct task_struct *tsk,
3110 struct fown_struct *fown, int sig)
3111 {
3112 return call_int_hook(file_send_sigiotask, tsk, fown, sig);
3113 }
3114
3115 /**
3116 * security_file_receive() - Check if receiving a file via IPC is allowed
3117 * @file: file being received
3118 *
3119 * This hook allows security modules to control the ability of a process to
3120 * receive an open file descriptor via socket IPC.
3121 *
3122 * Return: Returns 0 if permission is granted.
3123 */
security_file_receive(struct file * file)3124 int security_file_receive(struct file *file)
3125 {
3126 return call_int_hook(file_receive, file);
3127 }
3128
3129 /**
3130 * security_file_open() - Save open() time state for late use by the LSM
3131 * @file:
3132 *
3133 * Save open-time permission checking state for later use upon file_permission,
3134 * and recheck access if anything has changed since inode_permission.
3135 *
3136 * We can check if a file is opened for execution (e.g. execve(2) call), either
3137 * directly or indirectly (e.g. ELF's ld.so) by checking file->f_flags &
3138 * __FMODE_EXEC .
3139 *
3140 * Return: Returns 0 if permission is granted.
3141 */
security_file_open(struct file * file)3142 int security_file_open(struct file *file)
3143 {
3144 return call_int_hook(file_open, file);
3145 }
3146
3147 /**
3148 * security_file_post_open() - Evaluate a file after it has been opened
3149 * @file: the file
3150 * @mask: access mask
3151 *
3152 * Evaluate an opened file and the access mask requested with open(). The hook
3153 * is useful for LSMs that require the file content to be available in order to
3154 * make decisions.
3155 *
3156 * Return: Returns 0 if permission is granted.
3157 */
security_file_post_open(struct file * file,int mask)3158 int security_file_post_open(struct file *file, int mask)
3159 {
3160 return call_int_hook(file_post_open, file, mask);
3161 }
3162 EXPORT_SYMBOL_GPL(security_file_post_open);
3163
3164 /**
3165 * security_file_truncate() - Check if truncating a file is allowed
3166 * @file: file
3167 *
3168 * Check permission before truncating a file, i.e. using ftruncate. Note that
3169 * truncation permission may also be checked based on the path, using the
3170 * @path_truncate hook.
3171 *
3172 * Return: Returns 0 if permission is granted.
3173 */
security_file_truncate(struct file * file)3174 int security_file_truncate(struct file *file)
3175 {
3176 return call_int_hook(file_truncate, file);
3177 }
3178
3179 /**
3180 * security_task_alloc() - Allocate a task's LSM blob
3181 * @task: the task
3182 * @clone_flags: flags indicating what is being shared
3183 *
3184 * Handle allocation of task-related resources.
3185 *
3186 * Return: Returns a zero on success, negative values on failure.
3187 */
security_task_alloc(struct task_struct * task,unsigned long clone_flags)3188 int security_task_alloc(struct task_struct *task, unsigned long clone_flags)
3189 {
3190 int rc = lsm_task_alloc(task);
3191
3192 if (rc)
3193 return rc;
3194 rc = call_int_hook(task_alloc, task, clone_flags);
3195 if (unlikely(rc))
3196 security_task_free(task);
3197 return rc;
3198 }
3199
3200 /**
3201 * security_task_free() - Free a task's LSM blob and related resources
3202 * @task: task
3203 *
3204 * Handle release of task-related resources. Note that this can be called from
3205 * interrupt context.
3206 */
security_task_free(struct task_struct * task)3207 void security_task_free(struct task_struct *task)
3208 {
3209 call_void_hook(task_free, task);
3210
3211 kfree(task->security);
3212 task->security = NULL;
3213 }
3214
3215 /**
3216 * security_cred_alloc_blank() - Allocate the min memory to allow cred_transfer
3217 * @cred: credentials
3218 * @gfp: gfp flags
3219 *
3220 * Only allocate sufficient memory and attach to @cred such that
3221 * cred_transfer() will not get ENOMEM.
3222 *
3223 * Return: Returns 0 on success, negative values on failure.
3224 */
security_cred_alloc_blank(struct cred * cred,gfp_t gfp)3225 int security_cred_alloc_blank(struct cred *cred, gfp_t gfp)
3226 {
3227 int rc = lsm_cred_alloc(cred, gfp);
3228
3229 if (rc)
3230 return rc;
3231
3232 rc = call_int_hook(cred_alloc_blank, cred, gfp);
3233 if (unlikely(rc))
3234 security_cred_free(cred);
3235 return rc;
3236 }
3237
3238 /**
3239 * security_cred_free() - Free the cred's LSM blob and associated resources
3240 * @cred: credentials
3241 *
3242 * Deallocate and clear the cred->security field in a set of credentials.
3243 */
security_cred_free(struct cred * cred)3244 void security_cred_free(struct cred *cred)
3245 {
3246 /*
3247 * There is a failure case in prepare_creds() that
3248 * may result in a call here with ->security being NULL.
3249 */
3250 if (unlikely(cred->security == NULL))
3251 return;
3252
3253 call_void_hook(cred_free, cred);
3254
3255 kfree(cred->security);
3256 cred->security = NULL;
3257 }
3258
3259 /**
3260 * security_prepare_creds() - Prepare a new set of credentials
3261 * @new: new credentials
3262 * @old: original credentials
3263 * @gfp: gfp flags
3264 *
3265 * Prepare a new set of credentials by copying the data from the old set.
3266 *
3267 * Return: Returns 0 on success, negative values on failure.
3268 */
security_prepare_creds(struct cred * new,const struct cred * old,gfp_t gfp)3269 int security_prepare_creds(struct cred *new, const struct cred *old, gfp_t gfp)
3270 {
3271 int rc = lsm_cred_alloc(new, gfp);
3272
3273 if (rc)
3274 return rc;
3275
3276 rc = call_int_hook(cred_prepare, new, old, gfp);
3277 if (unlikely(rc))
3278 security_cred_free(new);
3279 return rc;
3280 }
3281
3282 /**
3283 * security_transfer_creds() - Transfer creds
3284 * @new: target credentials
3285 * @old: original credentials
3286 *
3287 * Transfer data from original creds to new creds.
3288 */
security_transfer_creds(struct cred * new,const struct cred * old)3289 void security_transfer_creds(struct cred *new, const struct cred *old)
3290 {
3291 call_void_hook(cred_transfer, new, old);
3292 }
3293
3294 /**
3295 * security_cred_getsecid() - Get the secid from a set of credentials
3296 * @c: credentials
3297 * @secid: secid value
3298 *
3299 * Retrieve the security identifier of the cred structure @c. In case of
3300 * failure, @secid will be set to zero.
3301 */
security_cred_getsecid(const struct cred * c,u32 * secid)3302 void security_cred_getsecid(const struct cred *c, u32 *secid)
3303 {
3304 *secid = 0;
3305 call_void_hook(cred_getsecid, c, secid);
3306 }
3307 EXPORT_SYMBOL(security_cred_getsecid);
3308
3309 /**
3310 * security_cred_getlsmprop() - Get the LSM data from a set of credentials
3311 * @c: credentials
3312 * @prop: destination for the LSM data
3313 *
3314 * Retrieve the security data of the cred structure @c. In case of
3315 * failure, @prop will be cleared.
3316 */
security_cred_getlsmprop(const struct cred * c,struct lsm_prop * prop)3317 void security_cred_getlsmprop(const struct cred *c, struct lsm_prop *prop)
3318 {
3319 lsmprop_init(prop);
3320 call_void_hook(cred_getlsmprop, c, prop);
3321 }
3322 EXPORT_SYMBOL(security_cred_getlsmprop);
3323
3324 /**
3325 * security_kernel_act_as() - Set the kernel credentials to act as secid
3326 * @new: credentials
3327 * @secid: secid
3328 *
3329 * Set the credentials for a kernel service to act as (subjective context).
3330 * The current task must be the one that nominated @secid.
3331 *
3332 * Return: Returns 0 if successful.
3333 */
security_kernel_act_as(struct cred * new,u32 secid)3334 int security_kernel_act_as(struct cred *new, u32 secid)
3335 {
3336 return call_int_hook(kernel_act_as, new, secid);
3337 }
3338
3339 /**
3340 * security_kernel_create_files_as() - Set file creation context using an inode
3341 * @new: target credentials
3342 * @inode: reference inode
3343 *
3344 * Set the file creation context in a set of credentials to be the same as the
3345 * objective context of the specified inode. The current task must be the one
3346 * that nominated @inode.
3347 *
3348 * Return: Returns 0 if successful.
3349 */
security_kernel_create_files_as(struct cred * new,struct inode * inode)3350 int security_kernel_create_files_as(struct cred *new, struct inode *inode)
3351 {
3352 return call_int_hook(kernel_create_files_as, new, inode);
3353 }
3354
3355 /**
3356 * security_kernel_module_request() - Check if loading a module is allowed
3357 * @kmod_name: module name
3358 *
3359 * Ability to trigger the kernel to automatically upcall to userspace for
3360 * userspace to load a kernel module with the given name.
3361 *
3362 * Return: Returns 0 if successful.
3363 */
security_kernel_module_request(char * kmod_name)3364 int security_kernel_module_request(char *kmod_name)
3365 {
3366 return call_int_hook(kernel_module_request, kmod_name);
3367 }
3368
3369 /**
3370 * security_kernel_read_file() - Read a file specified by userspace
3371 * @file: file
3372 * @id: file identifier
3373 * @contents: trust if security_kernel_post_read_file() will be called
3374 *
3375 * Read a file specified by userspace.
3376 *
3377 * Return: Returns 0 if permission is granted.
3378 */
security_kernel_read_file(struct file * file,enum kernel_read_file_id id,bool contents)3379 int security_kernel_read_file(struct file *file, enum kernel_read_file_id id,
3380 bool contents)
3381 {
3382 return call_int_hook(kernel_read_file, file, id, contents);
3383 }
3384 EXPORT_SYMBOL_GPL(security_kernel_read_file);
3385
3386 /**
3387 * security_kernel_post_read_file() - Read a file specified by userspace
3388 * @file: file
3389 * @buf: file contents
3390 * @size: size of file contents
3391 * @id: file identifier
3392 *
3393 * Read a file specified by userspace. This must be paired with a prior call
3394 * to security_kernel_read_file() call that indicated this hook would also be
3395 * called, see security_kernel_read_file() for more information.
3396 *
3397 * Return: Returns 0 if permission is granted.
3398 */
security_kernel_post_read_file(struct file * file,char * buf,loff_t size,enum kernel_read_file_id id)3399 int security_kernel_post_read_file(struct file *file, char *buf, loff_t size,
3400 enum kernel_read_file_id id)
3401 {
3402 return call_int_hook(kernel_post_read_file, file, buf, size, id);
3403 }
3404 EXPORT_SYMBOL_GPL(security_kernel_post_read_file);
3405
3406 /**
3407 * security_kernel_load_data() - Load data provided by userspace
3408 * @id: data identifier
3409 * @contents: true if security_kernel_post_load_data() will be called
3410 *
3411 * Load data provided by userspace.
3412 *
3413 * Return: Returns 0 if permission is granted.
3414 */
security_kernel_load_data(enum kernel_load_data_id id,bool contents)3415 int security_kernel_load_data(enum kernel_load_data_id id, bool contents)
3416 {
3417 return call_int_hook(kernel_load_data, id, contents);
3418 }
3419 EXPORT_SYMBOL_GPL(security_kernel_load_data);
3420
3421 /**
3422 * security_kernel_post_load_data() - Load userspace data from a non-file source
3423 * @buf: data
3424 * @size: size of data
3425 * @id: data identifier
3426 * @description: text description of data, specific to the id value
3427 *
3428 * Load data provided by a non-file source (usually userspace buffer). This
3429 * must be paired with a prior security_kernel_load_data() call that indicated
3430 * this hook would also be called, see security_kernel_load_data() for more
3431 * information.
3432 *
3433 * Return: Returns 0 if permission is granted.
3434 */
security_kernel_post_load_data(char * buf,loff_t size,enum kernel_load_data_id id,char * description)3435 int security_kernel_post_load_data(char *buf, loff_t size,
3436 enum kernel_load_data_id id,
3437 char *description)
3438 {
3439 return call_int_hook(kernel_post_load_data, buf, size, id, description);
3440 }
3441 EXPORT_SYMBOL_GPL(security_kernel_post_load_data);
3442
3443 /**
3444 * security_task_fix_setuid() - Update LSM with new user id attributes
3445 * @new: updated credentials
3446 * @old: credentials being replaced
3447 * @flags: LSM_SETID_* flag values
3448 *
3449 * Update the module's state after setting one or more of the user identity
3450 * attributes of the current process. The @flags parameter indicates which of
3451 * the set*uid system calls invoked this hook. If @new is the set of
3452 * credentials that will be installed. Modifications should be made to this
3453 * rather than to @current->cred.
3454 *
3455 * Return: Returns 0 on success.
3456 */
security_task_fix_setuid(struct cred * new,const struct cred * old,int flags)3457 int security_task_fix_setuid(struct cred *new, const struct cred *old,
3458 int flags)
3459 {
3460 return call_int_hook(task_fix_setuid, new, old, flags);
3461 }
3462
3463 /**
3464 * security_task_fix_setgid() - Update LSM with new group id attributes
3465 * @new: updated credentials
3466 * @old: credentials being replaced
3467 * @flags: LSM_SETID_* flag value
3468 *
3469 * Update the module's state after setting one or more of the group identity
3470 * attributes of the current process. The @flags parameter indicates which of
3471 * the set*gid system calls invoked this hook. @new is the set of credentials
3472 * that will be installed. Modifications should be made to this rather than to
3473 * @current->cred.
3474 *
3475 * Return: Returns 0 on success.
3476 */
security_task_fix_setgid(struct cred * new,const struct cred * old,int flags)3477 int security_task_fix_setgid(struct cred *new, const struct cred *old,
3478 int flags)
3479 {
3480 return call_int_hook(task_fix_setgid, new, old, flags);
3481 }
3482
3483 /**
3484 * security_task_fix_setgroups() - Update LSM with new supplementary groups
3485 * @new: updated credentials
3486 * @old: credentials being replaced
3487 *
3488 * Update the module's state after setting the supplementary group identity
3489 * attributes of the current process. @new is the set of credentials that will
3490 * be installed. Modifications should be made to this rather than to
3491 * @current->cred.
3492 *
3493 * Return: Returns 0 on success.
3494 */
security_task_fix_setgroups(struct cred * new,const struct cred * old)3495 int security_task_fix_setgroups(struct cred *new, const struct cred *old)
3496 {
3497 return call_int_hook(task_fix_setgroups, new, old);
3498 }
3499
3500 /**
3501 * security_task_setpgid() - Check if setting the pgid is allowed
3502 * @p: task being modified
3503 * @pgid: new pgid
3504 *
3505 * Check permission before setting the process group identifier of the process
3506 * @p to @pgid.
3507 *
3508 * Return: Returns 0 if permission is granted.
3509 */
security_task_setpgid(struct task_struct * p,pid_t pgid)3510 int security_task_setpgid(struct task_struct *p, pid_t pgid)
3511 {
3512 return call_int_hook(task_setpgid, p, pgid);
3513 }
3514
3515 /**
3516 * security_task_getpgid() - Check if getting the pgid is allowed
3517 * @p: task
3518 *
3519 * Check permission before getting the process group identifier of the process
3520 * @p.
3521 *
3522 * Return: Returns 0 if permission is granted.
3523 */
security_task_getpgid(struct task_struct * p)3524 int security_task_getpgid(struct task_struct *p)
3525 {
3526 return call_int_hook(task_getpgid, p);
3527 }
3528
3529 /**
3530 * security_task_getsid() - Check if getting the session id is allowed
3531 * @p: task
3532 *
3533 * Check permission before getting the session identifier of the process @p.
3534 *
3535 * Return: Returns 0 if permission is granted.
3536 */
security_task_getsid(struct task_struct * p)3537 int security_task_getsid(struct task_struct *p)
3538 {
3539 return call_int_hook(task_getsid, p);
3540 }
3541
3542 /**
3543 * security_current_getlsmprop_subj() - Current task's subjective LSM data
3544 * @prop: lsm specific information
3545 *
3546 * Retrieve the subjective security identifier of the current task and return
3547 * it in @prop.
3548 */
security_current_getlsmprop_subj(struct lsm_prop * prop)3549 void security_current_getlsmprop_subj(struct lsm_prop *prop)
3550 {
3551 lsmprop_init(prop);
3552 call_void_hook(current_getlsmprop_subj, prop);
3553 }
3554 EXPORT_SYMBOL(security_current_getlsmprop_subj);
3555
3556 /**
3557 * security_task_getlsmprop_obj() - Get a task's objective LSM data
3558 * @p: target task
3559 * @prop: lsm specific information
3560 *
3561 * Retrieve the objective security identifier of the task_struct in @p and
3562 * return it in @prop.
3563 */
security_task_getlsmprop_obj(struct task_struct * p,struct lsm_prop * prop)3564 void security_task_getlsmprop_obj(struct task_struct *p, struct lsm_prop *prop)
3565 {
3566 lsmprop_init(prop);
3567 call_void_hook(task_getlsmprop_obj, p, prop);
3568 }
3569 EXPORT_SYMBOL(security_task_getlsmprop_obj);
3570
3571 /**
3572 * security_task_setnice() - Check if setting a task's nice value is allowed
3573 * @p: target task
3574 * @nice: nice value
3575 *
3576 * Check permission before setting the nice value of @p to @nice.
3577 *
3578 * Return: Returns 0 if permission is granted.
3579 */
security_task_setnice(struct task_struct * p,int nice)3580 int security_task_setnice(struct task_struct *p, int nice)
3581 {
3582 return call_int_hook(task_setnice, p, nice);
3583 }
3584
3585 /**
3586 * security_task_setioprio() - Check if setting a task's ioprio is allowed
3587 * @p: target task
3588 * @ioprio: ioprio value
3589 *
3590 * Check permission before setting the ioprio value of @p to @ioprio.
3591 *
3592 * Return: Returns 0 if permission is granted.
3593 */
security_task_setioprio(struct task_struct * p,int ioprio)3594 int security_task_setioprio(struct task_struct *p, int ioprio)
3595 {
3596 return call_int_hook(task_setioprio, p, ioprio);
3597 }
3598
3599 /**
3600 * security_task_getioprio() - Check if getting a task's ioprio is allowed
3601 * @p: task
3602 *
3603 * Check permission before getting the ioprio value of @p.
3604 *
3605 * Return: Returns 0 if permission is granted.
3606 */
security_task_getioprio(struct task_struct * p)3607 int security_task_getioprio(struct task_struct *p)
3608 {
3609 return call_int_hook(task_getioprio, p);
3610 }
3611
3612 /**
3613 * security_task_prlimit() - Check if get/setting resources limits is allowed
3614 * @cred: current task credentials
3615 * @tcred: target task credentials
3616 * @flags: LSM_PRLIMIT_* flag bits indicating a get/set/both
3617 *
3618 * Check permission before getting and/or setting the resource limits of
3619 * another task.
3620 *
3621 * Return: Returns 0 if permission is granted.
3622 */
security_task_prlimit(const struct cred * cred,const struct cred * tcred,unsigned int flags)3623 int security_task_prlimit(const struct cred *cred, const struct cred *tcred,
3624 unsigned int flags)
3625 {
3626 return call_int_hook(task_prlimit, cred, tcred, flags);
3627 }
3628
3629 /**
3630 * security_task_setrlimit() - Check if setting a new rlimit value is allowed
3631 * @p: target task's group leader
3632 * @resource: resource whose limit is being set
3633 * @new_rlim: new resource limit
3634 *
3635 * Check permission before setting the resource limits of process @p for
3636 * @resource to @new_rlim. The old resource limit values can be examined by
3637 * dereferencing (p->signal->rlim + resource).
3638 *
3639 * Return: Returns 0 if permission is granted.
3640 */
security_task_setrlimit(struct task_struct * p,unsigned int resource,struct rlimit * new_rlim)3641 int security_task_setrlimit(struct task_struct *p, unsigned int resource,
3642 struct rlimit *new_rlim)
3643 {
3644 return call_int_hook(task_setrlimit, p, resource, new_rlim);
3645 }
3646
3647 /**
3648 * security_task_setscheduler() - Check if setting sched policy/param is allowed
3649 * @p: target task
3650 *
3651 * Check permission before setting scheduling policy and/or parameters of
3652 * process @p.
3653 *
3654 * Return: Returns 0 if permission is granted.
3655 */
security_task_setscheduler(struct task_struct * p)3656 int security_task_setscheduler(struct task_struct *p)
3657 {
3658 return call_int_hook(task_setscheduler, p);
3659 }
3660
3661 /**
3662 * security_task_getscheduler() - Check if getting scheduling info is allowed
3663 * @p: target task
3664 *
3665 * Check permission before obtaining scheduling information for process @p.
3666 *
3667 * Return: Returns 0 if permission is granted.
3668 */
security_task_getscheduler(struct task_struct * p)3669 int security_task_getscheduler(struct task_struct *p)
3670 {
3671 return call_int_hook(task_getscheduler, p);
3672 }
3673
3674 /**
3675 * security_task_movememory() - Check if moving memory is allowed
3676 * @p: task
3677 *
3678 * Check permission before moving memory owned by process @p.
3679 *
3680 * Return: Returns 0 if permission is granted.
3681 */
security_task_movememory(struct task_struct * p)3682 int security_task_movememory(struct task_struct *p)
3683 {
3684 return call_int_hook(task_movememory, p);
3685 }
3686
3687 /**
3688 * security_task_kill() - Check if sending a signal is allowed
3689 * @p: target process
3690 * @info: signal information
3691 * @sig: signal value
3692 * @cred: credentials of the signal sender, NULL if @current
3693 *
3694 * Check permission before sending signal @sig to @p. @info can be NULL, the
3695 * constant 1, or a pointer to a kernel_siginfo structure. If @info is 1 or
3696 * SI_FROMKERNEL(info) is true, then the signal should be viewed as coming from
3697 * the kernel and should typically be permitted. SIGIO signals are handled
3698 * separately by the send_sigiotask hook in file_security_ops.
3699 *
3700 * Return: Returns 0 if permission is granted.
3701 */
security_task_kill(struct task_struct * p,struct kernel_siginfo * info,int sig,const struct cred * cred)3702 int security_task_kill(struct task_struct *p, struct kernel_siginfo *info,
3703 int sig, const struct cred *cred)
3704 {
3705 return call_int_hook(task_kill, p, info, sig, cred);
3706 }
3707
3708 /**
3709 * security_task_prctl() - Check if a prctl op is allowed
3710 * @option: operation
3711 * @arg2: argument
3712 * @arg3: argument
3713 * @arg4: argument
3714 * @arg5: argument
3715 *
3716 * Check permission before performing a process control operation on the
3717 * current process.
3718 *
3719 * Return: Return -ENOSYS if no-one wanted to handle this op, any other value
3720 * to cause prctl() to return immediately with that value.
3721 */
security_task_prctl(int option,unsigned long arg2,unsigned long arg3,unsigned long arg4,unsigned long arg5)3722 int security_task_prctl(int option, unsigned long arg2, unsigned long arg3,
3723 unsigned long arg4, unsigned long arg5)
3724 {
3725 int thisrc;
3726 int rc = LSM_RET_DEFAULT(task_prctl);
3727 struct lsm_static_call *scall;
3728
3729 lsm_for_each_hook(scall, task_prctl) {
3730 thisrc = scall->hl->hook.task_prctl(option, arg2, arg3, arg4, arg5);
3731 if (thisrc != LSM_RET_DEFAULT(task_prctl)) {
3732 rc = thisrc;
3733 if (thisrc != 0)
3734 break;
3735 }
3736 }
3737 return rc;
3738 }
3739
3740 /**
3741 * security_task_to_inode() - Set the security attributes of a task's inode
3742 * @p: task
3743 * @inode: inode
3744 *
3745 * Set the security attributes for an inode based on an associated task's
3746 * security attributes, e.g. for /proc/pid inodes.
3747 */
security_task_to_inode(struct task_struct * p,struct inode * inode)3748 void security_task_to_inode(struct task_struct *p, struct inode *inode)
3749 {
3750 call_void_hook(task_to_inode, p, inode);
3751 }
3752
3753 /**
3754 * security_create_user_ns() - Check if creating a new userns is allowed
3755 * @cred: prepared creds
3756 *
3757 * Check permission prior to creating a new user namespace.
3758 *
3759 * Return: Returns 0 if successful, otherwise < 0 error code.
3760 */
security_create_user_ns(const struct cred * cred)3761 int security_create_user_ns(const struct cred *cred)
3762 {
3763 return call_int_hook(userns_create, cred);
3764 }
3765
3766 /**
3767 * security_ipc_permission() - Check if sysv ipc access is allowed
3768 * @ipcp: ipc permission structure
3769 * @flag: requested permissions
3770 *
3771 * Check permissions for access to IPC.
3772 *
3773 * Return: Returns 0 if permission is granted.
3774 */
security_ipc_permission(struct kern_ipc_perm * ipcp,short flag)3775 int security_ipc_permission(struct kern_ipc_perm *ipcp, short flag)
3776 {
3777 return call_int_hook(ipc_permission, ipcp, flag);
3778 }
3779
3780 /**
3781 * security_ipc_getlsmprop() - Get the sysv ipc object LSM data
3782 * @ipcp: ipc permission structure
3783 * @prop: pointer to lsm information
3784 *
3785 * Get the lsm information associated with the ipc object.
3786 */
3787
security_ipc_getlsmprop(struct kern_ipc_perm * ipcp,struct lsm_prop * prop)3788 void security_ipc_getlsmprop(struct kern_ipc_perm *ipcp, struct lsm_prop *prop)
3789 {
3790 lsmprop_init(prop);
3791 call_void_hook(ipc_getlsmprop, ipcp, prop);
3792 }
3793
3794 /**
3795 * security_msg_msg_alloc() - Allocate a sysv ipc message LSM blob
3796 * @msg: message structure
3797 *
3798 * Allocate and attach a security structure to the msg->security field. The
3799 * security field is initialized to NULL when the structure is first created.
3800 *
3801 * Return: Return 0 if operation was successful and permission is granted.
3802 */
security_msg_msg_alloc(struct msg_msg * msg)3803 int security_msg_msg_alloc(struct msg_msg *msg)
3804 {
3805 int rc = lsm_msg_msg_alloc(msg);
3806
3807 if (unlikely(rc))
3808 return rc;
3809 rc = call_int_hook(msg_msg_alloc_security, msg);
3810 if (unlikely(rc))
3811 security_msg_msg_free(msg);
3812 return rc;
3813 }
3814
3815 /**
3816 * security_msg_msg_free() - Free a sysv ipc message LSM blob
3817 * @msg: message structure
3818 *
3819 * Deallocate the security structure for this message.
3820 */
security_msg_msg_free(struct msg_msg * msg)3821 void security_msg_msg_free(struct msg_msg *msg)
3822 {
3823 call_void_hook(msg_msg_free_security, msg);
3824 kfree(msg->security);
3825 msg->security = NULL;
3826 }
3827
3828 /**
3829 * security_msg_queue_alloc() - Allocate a sysv ipc msg queue LSM blob
3830 * @msq: sysv ipc permission structure
3831 *
3832 * Allocate and attach a security structure to @msg. The security field is
3833 * initialized to NULL when the structure is first created.
3834 *
3835 * Return: Returns 0 if operation was successful and permission is granted.
3836 */
security_msg_queue_alloc(struct kern_ipc_perm * msq)3837 int security_msg_queue_alloc(struct kern_ipc_perm *msq)
3838 {
3839 int rc = lsm_ipc_alloc(msq);
3840
3841 if (unlikely(rc))
3842 return rc;
3843 rc = call_int_hook(msg_queue_alloc_security, msq);
3844 if (unlikely(rc))
3845 security_msg_queue_free(msq);
3846 return rc;
3847 }
3848
3849 /**
3850 * security_msg_queue_free() - Free a sysv ipc msg queue LSM blob
3851 * @msq: sysv ipc permission structure
3852 *
3853 * Deallocate security field @perm->security for the message queue.
3854 */
security_msg_queue_free(struct kern_ipc_perm * msq)3855 void security_msg_queue_free(struct kern_ipc_perm *msq)
3856 {
3857 call_void_hook(msg_queue_free_security, msq);
3858 kfree(msq->security);
3859 msq->security = NULL;
3860 }
3861
3862 /**
3863 * security_msg_queue_associate() - Check if a msg queue operation is allowed
3864 * @msq: sysv ipc permission structure
3865 * @msqflg: operation flags
3866 *
3867 * Check permission when a message queue is requested through the msgget system
3868 * call. This hook is only called when returning the message queue identifier
3869 * for an existing message queue, not when a new message queue is created.
3870 *
3871 * Return: Return 0 if permission is granted.
3872 */
security_msg_queue_associate(struct kern_ipc_perm * msq,int msqflg)3873 int security_msg_queue_associate(struct kern_ipc_perm *msq, int msqflg)
3874 {
3875 return call_int_hook(msg_queue_associate, msq, msqflg);
3876 }
3877
3878 /**
3879 * security_msg_queue_msgctl() - Check if a msg queue operation is allowed
3880 * @msq: sysv ipc permission structure
3881 * @cmd: operation
3882 *
3883 * Check permission when a message control operation specified by @cmd is to be
3884 * performed on the message queue with permissions.
3885 *
3886 * Return: Returns 0 if permission is granted.
3887 */
security_msg_queue_msgctl(struct kern_ipc_perm * msq,int cmd)3888 int security_msg_queue_msgctl(struct kern_ipc_perm *msq, int cmd)
3889 {
3890 return call_int_hook(msg_queue_msgctl, msq, cmd);
3891 }
3892
3893 /**
3894 * security_msg_queue_msgsnd() - Check if sending a sysv ipc message is allowed
3895 * @msq: sysv ipc permission structure
3896 * @msg: message
3897 * @msqflg: operation flags
3898 *
3899 * Check permission before a message, @msg, is enqueued on the message queue
3900 * with permissions specified in @msq.
3901 *
3902 * Return: Returns 0 if permission is granted.
3903 */
security_msg_queue_msgsnd(struct kern_ipc_perm * msq,struct msg_msg * msg,int msqflg)3904 int security_msg_queue_msgsnd(struct kern_ipc_perm *msq,
3905 struct msg_msg *msg, int msqflg)
3906 {
3907 return call_int_hook(msg_queue_msgsnd, msq, msg, msqflg);
3908 }
3909
3910 /**
3911 * security_msg_queue_msgrcv() - Check if receiving a sysv ipc msg is allowed
3912 * @msq: sysv ipc permission structure
3913 * @msg: message
3914 * @target: target task
3915 * @type: type of message requested
3916 * @mode: operation flags
3917 *
3918 * Check permission before a message, @msg, is removed from the message queue.
3919 * The @target task structure contains a pointer to the process that will be
3920 * receiving the message (not equal to the current process when inline receives
3921 * are being performed).
3922 *
3923 * Return: Returns 0 if permission is granted.
3924 */
security_msg_queue_msgrcv(struct kern_ipc_perm * msq,struct msg_msg * msg,struct task_struct * target,long type,int mode)3925 int security_msg_queue_msgrcv(struct kern_ipc_perm *msq, struct msg_msg *msg,
3926 struct task_struct *target, long type, int mode)
3927 {
3928 return call_int_hook(msg_queue_msgrcv, msq, msg, target, type, mode);
3929 }
3930
3931 /**
3932 * security_shm_alloc() - Allocate a sysv shm LSM blob
3933 * @shp: sysv ipc permission structure
3934 *
3935 * Allocate and attach a security structure to the @shp security field. The
3936 * security field is initialized to NULL when the structure is first created.
3937 *
3938 * Return: Returns 0 if operation was successful and permission is granted.
3939 */
security_shm_alloc(struct kern_ipc_perm * shp)3940 int security_shm_alloc(struct kern_ipc_perm *shp)
3941 {
3942 int rc = lsm_ipc_alloc(shp);
3943
3944 if (unlikely(rc))
3945 return rc;
3946 rc = call_int_hook(shm_alloc_security, shp);
3947 if (unlikely(rc))
3948 security_shm_free(shp);
3949 return rc;
3950 }
3951
3952 /**
3953 * security_shm_free() - Free a sysv shm LSM blob
3954 * @shp: sysv ipc permission structure
3955 *
3956 * Deallocate the security structure @perm->security for the memory segment.
3957 */
security_shm_free(struct kern_ipc_perm * shp)3958 void security_shm_free(struct kern_ipc_perm *shp)
3959 {
3960 call_void_hook(shm_free_security, shp);
3961 kfree(shp->security);
3962 shp->security = NULL;
3963 }
3964
3965 /**
3966 * security_shm_associate() - Check if a sysv shm operation is allowed
3967 * @shp: sysv ipc permission structure
3968 * @shmflg: operation flags
3969 *
3970 * Check permission when a shared memory region is requested through the shmget
3971 * system call. This hook is only called when returning the shared memory
3972 * region identifier for an existing region, not when a new shared memory
3973 * region is created.
3974 *
3975 * Return: Returns 0 if permission is granted.
3976 */
security_shm_associate(struct kern_ipc_perm * shp,int shmflg)3977 int security_shm_associate(struct kern_ipc_perm *shp, int shmflg)
3978 {
3979 return call_int_hook(shm_associate, shp, shmflg);
3980 }
3981
3982 /**
3983 * security_shm_shmctl() - Check if a sysv shm operation is allowed
3984 * @shp: sysv ipc permission structure
3985 * @cmd: operation
3986 *
3987 * Check permission when a shared memory control operation specified by @cmd is
3988 * to be performed on the shared memory region with permissions in @shp.
3989 *
3990 * Return: Return 0 if permission is granted.
3991 */
security_shm_shmctl(struct kern_ipc_perm * shp,int cmd)3992 int security_shm_shmctl(struct kern_ipc_perm *shp, int cmd)
3993 {
3994 return call_int_hook(shm_shmctl, shp, cmd);
3995 }
3996
3997 /**
3998 * security_shm_shmat() - Check if a sysv shm attach operation is allowed
3999 * @shp: sysv ipc permission structure
4000 * @shmaddr: address of memory region to attach
4001 * @shmflg: operation flags
4002 *
4003 * Check permissions prior to allowing the shmat system call to attach the
4004 * shared memory segment with permissions @shp to the data segment of the
4005 * calling process. The attaching address is specified by @shmaddr.
4006 *
4007 * Return: Returns 0 if permission is granted.
4008 */
security_shm_shmat(struct kern_ipc_perm * shp,char __user * shmaddr,int shmflg)4009 int security_shm_shmat(struct kern_ipc_perm *shp,
4010 char __user *shmaddr, int shmflg)
4011 {
4012 return call_int_hook(shm_shmat, shp, shmaddr, shmflg);
4013 }
4014
4015 /**
4016 * security_sem_alloc() - Allocate a sysv semaphore LSM blob
4017 * @sma: sysv ipc permission structure
4018 *
4019 * Allocate and attach a security structure to the @sma security field. The
4020 * security field is initialized to NULL when the structure is first created.
4021 *
4022 * Return: Returns 0 if operation was successful and permission is granted.
4023 */
security_sem_alloc(struct kern_ipc_perm * sma)4024 int security_sem_alloc(struct kern_ipc_perm *sma)
4025 {
4026 int rc = lsm_ipc_alloc(sma);
4027
4028 if (unlikely(rc))
4029 return rc;
4030 rc = call_int_hook(sem_alloc_security, sma);
4031 if (unlikely(rc))
4032 security_sem_free(sma);
4033 return rc;
4034 }
4035
4036 /**
4037 * security_sem_free() - Free a sysv semaphore LSM blob
4038 * @sma: sysv ipc permission structure
4039 *
4040 * Deallocate security structure @sma->security for the semaphore.
4041 */
security_sem_free(struct kern_ipc_perm * sma)4042 void security_sem_free(struct kern_ipc_perm *sma)
4043 {
4044 call_void_hook(sem_free_security, sma);
4045 kfree(sma->security);
4046 sma->security = NULL;
4047 }
4048
4049 /**
4050 * security_sem_associate() - Check if a sysv semaphore operation is allowed
4051 * @sma: sysv ipc permission structure
4052 * @semflg: operation flags
4053 *
4054 * Check permission when a semaphore is requested through the semget system
4055 * call. This hook is only called when returning the semaphore identifier for
4056 * an existing semaphore, not when a new one must be created.
4057 *
4058 * Return: Returns 0 if permission is granted.
4059 */
security_sem_associate(struct kern_ipc_perm * sma,int semflg)4060 int security_sem_associate(struct kern_ipc_perm *sma, int semflg)
4061 {
4062 return call_int_hook(sem_associate, sma, semflg);
4063 }
4064
4065 /**
4066 * security_sem_semctl() - Check if a sysv semaphore operation is allowed
4067 * @sma: sysv ipc permission structure
4068 * @cmd: operation
4069 *
4070 * Check permission when a semaphore operation specified by @cmd is to be
4071 * performed on the semaphore.
4072 *
4073 * Return: Returns 0 if permission is granted.
4074 */
security_sem_semctl(struct kern_ipc_perm * sma,int cmd)4075 int security_sem_semctl(struct kern_ipc_perm *sma, int cmd)
4076 {
4077 return call_int_hook(sem_semctl, sma, cmd);
4078 }
4079
4080 /**
4081 * security_sem_semop() - Check if a sysv semaphore operation is allowed
4082 * @sma: sysv ipc permission structure
4083 * @sops: operations to perform
4084 * @nsops: number of operations
4085 * @alter: flag indicating changes will be made
4086 *
4087 * Check permissions before performing operations on members of the semaphore
4088 * set. If the @alter flag is nonzero, the semaphore set may be modified.
4089 *
4090 * Return: Returns 0 if permission is granted.
4091 */
security_sem_semop(struct kern_ipc_perm * sma,struct sembuf * sops,unsigned nsops,int alter)4092 int security_sem_semop(struct kern_ipc_perm *sma, struct sembuf *sops,
4093 unsigned nsops, int alter)
4094 {
4095 return call_int_hook(sem_semop, sma, sops, nsops, alter);
4096 }
4097
4098 /**
4099 * security_d_instantiate() - Populate an inode's LSM state based on a dentry
4100 * @dentry: dentry
4101 * @inode: inode
4102 *
4103 * Fill in @inode security information for a @dentry if allowed.
4104 */
security_d_instantiate(struct dentry * dentry,struct inode * inode)4105 void security_d_instantiate(struct dentry *dentry, struct inode *inode)
4106 {
4107 if (unlikely(inode && IS_PRIVATE(inode)))
4108 return;
4109 call_void_hook(d_instantiate, dentry, inode);
4110 }
4111 EXPORT_SYMBOL(security_d_instantiate);
4112
4113 /*
4114 * Please keep this in sync with it's counterpart in security/lsm_syscalls.c
4115 */
4116
4117 /**
4118 * security_getselfattr - Read an LSM attribute of the current process.
4119 * @attr: which attribute to return
4120 * @uctx: the user-space destination for the information, or NULL
4121 * @size: pointer to the size of space available to receive the data
4122 * @flags: special handling options. LSM_FLAG_SINGLE indicates that only
4123 * attributes associated with the LSM identified in the passed @ctx be
4124 * reported.
4125 *
4126 * A NULL value for @uctx can be used to get both the number of attributes
4127 * and the size of the data.
4128 *
4129 * Returns the number of attributes found on success, negative value
4130 * on error. @size is reset to the total size of the data.
4131 * If @size is insufficient to contain the data -E2BIG is returned.
4132 */
security_getselfattr(unsigned int attr,struct lsm_ctx __user * uctx,u32 __user * size,u32 flags)4133 int security_getselfattr(unsigned int attr, struct lsm_ctx __user *uctx,
4134 u32 __user *size, u32 flags)
4135 {
4136 struct lsm_static_call *scall;
4137 struct lsm_ctx lctx = { .id = LSM_ID_UNDEF, };
4138 u8 __user *base = (u8 __user *)uctx;
4139 u32 entrysize;
4140 u32 total = 0;
4141 u32 left;
4142 bool toobig = false;
4143 bool single = false;
4144 int count = 0;
4145 int rc;
4146
4147 if (attr == LSM_ATTR_UNDEF)
4148 return -EINVAL;
4149 if (size == NULL)
4150 return -EINVAL;
4151 if (get_user(left, size))
4152 return -EFAULT;
4153
4154 if (flags) {
4155 /*
4156 * Only flag supported is LSM_FLAG_SINGLE
4157 */
4158 if (flags != LSM_FLAG_SINGLE || !uctx)
4159 return -EINVAL;
4160 if (copy_from_user(&lctx, uctx, sizeof(lctx)))
4161 return -EFAULT;
4162 /*
4163 * If the LSM ID isn't specified it is an error.
4164 */
4165 if (lctx.id == LSM_ID_UNDEF)
4166 return -EINVAL;
4167 single = true;
4168 }
4169
4170 /*
4171 * In the usual case gather all the data from the LSMs.
4172 * In the single case only get the data from the LSM specified.
4173 */
4174 lsm_for_each_hook(scall, getselfattr) {
4175 if (single && lctx.id != scall->hl->lsmid->id)
4176 continue;
4177 entrysize = left;
4178 if (base)
4179 uctx = (struct lsm_ctx __user *)(base + total);
4180 rc = scall->hl->hook.getselfattr(attr, uctx, &entrysize, flags);
4181 if (rc == -EOPNOTSUPP)
4182 continue;
4183 if (rc == -E2BIG) {
4184 rc = 0;
4185 left = 0;
4186 toobig = true;
4187 } else if (rc < 0)
4188 return rc;
4189 else
4190 left -= entrysize;
4191
4192 total += entrysize;
4193 count += rc;
4194 if (single)
4195 break;
4196 }
4197 if (put_user(total, size))
4198 return -EFAULT;
4199 if (toobig)
4200 return -E2BIG;
4201 if (count == 0)
4202 return LSM_RET_DEFAULT(getselfattr);
4203 return count;
4204 }
4205
4206 /*
4207 * Please keep this in sync with it's counterpart in security/lsm_syscalls.c
4208 */
4209
4210 /**
4211 * security_setselfattr - Set an LSM attribute on the current process.
4212 * @attr: which attribute to set
4213 * @uctx: the user-space source for the information
4214 * @size: the size of the data
4215 * @flags: reserved for future use, must be 0
4216 *
4217 * Set an LSM attribute for the current process. The LSM, attribute
4218 * and new value are included in @uctx.
4219 *
4220 * Returns 0 on success, -EINVAL if the input is inconsistent, -EFAULT
4221 * if the user buffer is inaccessible, E2BIG if size is too big, or an
4222 * LSM specific failure.
4223 */
security_setselfattr(unsigned int attr,struct lsm_ctx __user * uctx,u32 size,u32 flags)4224 int security_setselfattr(unsigned int attr, struct lsm_ctx __user *uctx,
4225 u32 size, u32 flags)
4226 {
4227 struct lsm_static_call *scall;
4228 struct lsm_ctx *lctx;
4229 int rc = LSM_RET_DEFAULT(setselfattr);
4230 u64 required_len;
4231
4232 if (flags)
4233 return -EINVAL;
4234 if (size < sizeof(*lctx))
4235 return -EINVAL;
4236 if (size > PAGE_SIZE)
4237 return -E2BIG;
4238
4239 lctx = memdup_user(uctx, size);
4240 if (IS_ERR(lctx))
4241 return PTR_ERR(lctx);
4242
4243 if (size < lctx->len ||
4244 check_add_overflow(sizeof(*lctx), lctx->ctx_len, &required_len) ||
4245 lctx->len < required_len) {
4246 rc = -EINVAL;
4247 goto free_out;
4248 }
4249
4250 lsm_for_each_hook(scall, setselfattr)
4251 if ((scall->hl->lsmid->id) == lctx->id) {
4252 rc = scall->hl->hook.setselfattr(attr, lctx, size, flags);
4253 break;
4254 }
4255
4256 free_out:
4257 kfree(lctx);
4258 return rc;
4259 }
4260
4261 /**
4262 * security_getprocattr() - Read an attribute for a task
4263 * @p: the task
4264 * @lsmid: LSM identification
4265 * @name: attribute name
4266 * @value: attribute value
4267 *
4268 * Read attribute @name for task @p and store it into @value if allowed.
4269 *
4270 * Return: Returns the length of @value on success, a negative value otherwise.
4271 */
security_getprocattr(struct task_struct * p,int lsmid,const char * name,char ** value)4272 int security_getprocattr(struct task_struct *p, int lsmid, const char *name,
4273 char **value)
4274 {
4275 struct lsm_static_call *scall;
4276
4277 lsm_for_each_hook(scall, getprocattr) {
4278 if (lsmid != 0 && lsmid != scall->hl->lsmid->id)
4279 continue;
4280 return scall->hl->hook.getprocattr(p, name, value);
4281 }
4282 return LSM_RET_DEFAULT(getprocattr);
4283 }
4284
4285 /**
4286 * security_setprocattr() - Set an attribute for a task
4287 * @lsmid: LSM identification
4288 * @name: attribute name
4289 * @value: attribute value
4290 * @size: attribute value size
4291 *
4292 * Write (set) the current task's attribute @name to @value, size @size if
4293 * allowed.
4294 *
4295 * Return: Returns bytes written on success, a negative value otherwise.
4296 */
security_setprocattr(int lsmid,const char * name,void * value,size_t size)4297 int security_setprocattr(int lsmid, const char *name, void *value, size_t size)
4298 {
4299 struct lsm_static_call *scall;
4300
4301 lsm_for_each_hook(scall, setprocattr) {
4302 if (lsmid != 0 && lsmid != scall->hl->lsmid->id)
4303 continue;
4304 return scall->hl->hook.setprocattr(name, value, size);
4305 }
4306 return LSM_RET_DEFAULT(setprocattr);
4307 }
4308
4309 /**
4310 * security_ismaclabel() - Check if the named attribute is a MAC label
4311 * @name: full extended attribute name
4312 *
4313 * Check if the extended attribute specified by @name represents a MAC label.
4314 *
4315 * Return: Returns 1 if name is a MAC attribute otherwise returns 0.
4316 */
security_ismaclabel(const char * name)4317 int security_ismaclabel(const char *name)
4318 {
4319 return call_int_hook(ismaclabel, name);
4320 }
4321 EXPORT_SYMBOL(security_ismaclabel);
4322
4323 /**
4324 * security_secid_to_secctx() - Convert a secid to a secctx
4325 * @secid: secid
4326 * @cp: the LSM context
4327 *
4328 * Convert secid to security context. If @cp is NULL the length of the
4329 * result will be returned, but no data will be returned. This
4330 * does mean that the length could change between calls to check the length and
4331 * the next call which actually allocates and returns the data.
4332 *
4333 * Return: Return length of data on success, error on failure.
4334 */
security_secid_to_secctx(u32 secid,struct lsm_context * cp)4335 int security_secid_to_secctx(u32 secid, struct lsm_context *cp)
4336 {
4337 return call_int_hook(secid_to_secctx, secid, cp);
4338 }
4339 EXPORT_SYMBOL(security_secid_to_secctx);
4340
4341 /**
4342 * security_lsmprop_to_secctx() - Convert a lsm_prop to a secctx
4343 * @prop: lsm specific information
4344 * @cp: the LSM context
4345 *
4346 * Convert a @prop entry to security context. If @cp is NULL the
4347 * length of the result will be returned. This does mean that the
4348 * length could change between calls to check the length and the
4349 * next call which actually allocates and returns the @cp.
4350 *
4351 * Return: Return length of data on success, error on failure.
4352 */
security_lsmprop_to_secctx(struct lsm_prop * prop,struct lsm_context * cp)4353 int security_lsmprop_to_secctx(struct lsm_prop *prop, struct lsm_context *cp)
4354 {
4355 return call_int_hook(lsmprop_to_secctx, prop, cp);
4356 }
4357 EXPORT_SYMBOL(security_lsmprop_to_secctx);
4358
4359 /**
4360 * security_secctx_to_secid() - Convert a secctx to a secid
4361 * @secdata: secctx
4362 * @seclen: length of secctx
4363 * @secid: secid
4364 *
4365 * Convert security context to secid.
4366 *
4367 * Return: Returns 0 on success, error on failure.
4368 */
security_secctx_to_secid(const char * secdata,u32 seclen,u32 * secid)4369 int security_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
4370 {
4371 *secid = 0;
4372 return call_int_hook(secctx_to_secid, secdata, seclen, secid);
4373 }
4374 EXPORT_SYMBOL(security_secctx_to_secid);
4375
4376 /**
4377 * security_release_secctx() - Free a secctx buffer
4378 * @cp: the security context
4379 *
4380 * Release the security context.
4381 */
security_release_secctx(struct lsm_context * cp)4382 void security_release_secctx(struct lsm_context *cp)
4383 {
4384 call_void_hook(release_secctx, cp);
4385 memset(cp, 0, sizeof(*cp));
4386 }
4387 EXPORT_SYMBOL(security_release_secctx);
4388
4389 /**
4390 * security_inode_invalidate_secctx() - Invalidate an inode's security label
4391 * @inode: inode
4392 *
4393 * Notify the security module that it must revalidate the security context of
4394 * an inode.
4395 */
security_inode_invalidate_secctx(struct inode * inode)4396 void security_inode_invalidate_secctx(struct inode *inode)
4397 {
4398 call_void_hook(inode_invalidate_secctx, inode);
4399 }
4400 EXPORT_SYMBOL(security_inode_invalidate_secctx);
4401
4402 /**
4403 * security_inode_notifysecctx() - Notify the LSM of an inode's security label
4404 * @inode: inode
4405 * @ctx: secctx
4406 * @ctxlen: length of secctx
4407 *
4408 * Notify the security module of what the security context of an inode should
4409 * be. Initializes the incore security context managed by the security module
4410 * for this inode. Example usage: NFS client invokes this hook to initialize
4411 * the security context in its incore inode to the value provided by the server
4412 * for the file when the server returned the file's attributes to the client.
4413 * Must be called with inode->i_mutex locked.
4414 *
4415 * Return: Returns 0 on success, error on failure.
4416 */
security_inode_notifysecctx(struct inode * inode,void * ctx,u32 ctxlen)4417 int security_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen)
4418 {
4419 return call_int_hook(inode_notifysecctx, inode, ctx, ctxlen);
4420 }
4421 EXPORT_SYMBOL(security_inode_notifysecctx);
4422
4423 /**
4424 * security_inode_setsecctx() - Change the security label of an inode
4425 * @dentry: inode
4426 * @ctx: secctx
4427 * @ctxlen: length of secctx
4428 *
4429 * Change the security context of an inode. Updates the incore security
4430 * context managed by the security module and invokes the fs code as needed
4431 * (via __vfs_setxattr_noperm) to update any backing xattrs that represent the
4432 * context. Example usage: NFS server invokes this hook to change the security
4433 * context in its incore inode and on the backing filesystem to a value
4434 * provided by the client on a SETATTR operation. Must be called with
4435 * inode->i_mutex locked.
4436 *
4437 * Return: Returns 0 on success, error on failure.
4438 */
security_inode_setsecctx(struct dentry * dentry,void * ctx,u32 ctxlen)4439 int security_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen)
4440 {
4441 return call_int_hook(inode_setsecctx, dentry, ctx, ctxlen);
4442 }
4443 EXPORT_SYMBOL(security_inode_setsecctx);
4444
4445 /**
4446 * security_inode_getsecctx() - Get the security label of an inode
4447 * @inode: inode
4448 * @cp: security context
4449 *
4450 * On success, returns 0 and fills out @cp with the security context
4451 * for the given @inode.
4452 *
4453 * Return: Returns 0 on success, error on failure.
4454 */
security_inode_getsecctx(struct inode * inode,struct lsm_context * cp)4455 int security_inode_getsecctx(struct inode *inode, struct lsm_context *cp)
4456 {
4457 memset(cp, 0, sizeof(*cp));
4458 return call_int_hook(inode_getsecctx, inode, cp);
4459 }
4460 EXPORT_SYMBOL(security_inode_getsecctx);
4461
4462 #ifdef CONFIG_WATCH_QUEUE
4463 /**
4464 * security_post_notification() - Check if a watch notification can be posted
4465 * @w_cred: credentials of the task that set the watch
4466 * @cred: credentials of the task which triggered the watch
4467 * @n: the notification
4468 *
4469 * Check to see if a watch notification can be posted to a particular queue.
4470 *
4471 * Return: Returns 0 if permission is granted.
4472 */
security_post_notification(const struct cred * w_cred,const struct cred * cred,struct watch_notification * n)4473 int security_post_notification(const struct cred *w_cred,
4474 const struct cred *cred,
4475 struct watch_notification *n)
4476 {
4477 return call_int_hook(post_notification, w_cred, cred, n);
4478 }
4479 #endif /* CONFIG_WATCH_QUEUE */
4480
4481 #ifdef CONFIG_KEY_NOTIFICATIONS
4482 /**
4483 * security_watch_key() - Check if a task is allowed to watch for key events
4484 * @key: the key to watch
4485 *
4486 * Check to see if a process is allowed to watch for event notifications from
4487 * a key or keyring.
4488 *
4489 * Return: Returns 0 if permission is granted.
4490 */
security_watch_key(struct key * key)4491 int security_watch_key(struct key *key)
4492 {
4493 return call_int_hook(watch_key, key);
4494 }
4495 #endif /* CONFIG_KEY_NOTIFICATIONS */
4496
4497 #ifdef CONFIG_SECURITY_NETWORK
4498 /**
4499 * security_netlink_send() - Save info and check if netlink sending is allowed
4500 * @sk: sending socket
4501 * @skb: netlink message
4502 *
4503 * Save security information for a netlink message so that permission checking
4504 * can be performed when the message is processed. The security information
4505 * can be saved using the eff_cap field of the netlink_skb_parms structure.
4506 * Also may be used to provide fine grained control over message transmission.
4507 *
4508 * Return: Returns 0 if the information was successfully saved and message is
4509 * allowed to be transmitted.
4510 */
security_netlink_send(struct sock * sk,struct sk_buff * skb)4511 int security_netlink_send(struct sock *sk, struct sk_buff *skb)
4512 {
4513 return call_int_hook(netlink_send, sk, skb);
4514 }
4515
4516 /**
4517 * security_unix_stream_connect() - Check if a AF_UNIX stream is allowed
4518 * @sock: originating sock
4519 * @other: peer sock
4520 * @newsk: new sock
4521 *
4522 * Check permissions before establishing a Unix domain stream connection
4523 * between @sock and @other.
4524 *
4525 * The @unix_stream_connect and @unix_may_send hooks were necessary because
4526 * Linux provides an alternative to the conventional file name space for Unix
4527 * domain sockets. Whereas binding and connecting to sockets in the file name
4528 * space is mediated by the typical file permissions (and caught by the mknod
4529 * and permission hooks in inode_security_ops), binding and connecting to
4530 * sockets in the abstract name space is completely unmediated. Sufficient
4531 * control of Unix domain sockets in the abstract name space isn't possible
4532 * using only the socket layer hooks, since we need to know the actual target
4533 * socket, which is not looked up until we are inside the af_unix code.
4534 *
4535 * Return: Returns 0 if permission is granted.
4536 */
security_unix_stream_connect(struct sock * sock,struct sock * other,struct sock * newsk)4537 int security_unix_stream_connect(struct sock *sock, struct sock *other,
4538 struct sock *newsk)
4539 {
4540 return call_int_hook(unix_stream_connect, sock, other, newsk);
4541 }
4542 EXPORT_SYMBOL(security_unix_stream_connect);
4543
4544 /**
4545 * security_unix_may_send() - Check if AF_UNIX socket can send datagrams
4546 * @sock: originating sock
4547 * @other: peer sock
4548 *
4549 * Check permissions before connecting or sending datagrams from @sock to
4550 * @other.
4551 *
4552 * The @unix_stream_connect and @unix_may_send hooks were necessary because
4553 * Linux provides an alternative to the conventional file name space for Unix
4554 * domain sockets. Whereas binding and connecting to sockets in the file name
4555 * space is mediated by the typical file permissions (and caught by the mknod
4556 * and permission hooks in inode_security_ops), binding and connecting to
4557 * sockets in the abstract name space is completely unmediated. Sufficient
4558 * control of Unix domain sockets in the abstract name space isn't possible
4559 * using only the socket layer hooks, since we need to know the actual target
4560 * socket, which is not looked up until we are inside the af_unix code.
4561 *
4562 * Return: Returns 0 if permission is granted.
4563 */
security_unix_may_send(struct socket * sock,struct socket * other)4564 int security_unix_may_send(struct socket *sock, struct socket *other)
4565 {
4566 return call_int_hook(unix_may_send, sock, other);
4567 }
4568 EXPORT_SYMBOL(security_unix_may_send);
4569
4570 /**
4571 * security_socket_create() - Check if creating a new socket is allowed
4572 * @family: protocol family
4573 * @type: communications type
4574 * @protocol: requested protocol
4575 * @kern: set to 1 if a kernel socket is requested
4576 *
4577 * Check permissions prior to creating a new socket.
4578 *
4579 * Return: Returns 0 if permission is granted.
4580 */
security_socket_create(int family,int type,int protocol,int kern)4581 int security_socket_create(int family, int type, int protocol, int kern)
4582 {
4583 return call_int_hook(socket_create, family, type, protocol, kern);
4584 }
4585
4586 /**
4587 * security_socket_post_create() - Initialize a newly created socket
4588 * @sock: socket
4589 * @family: protocol family
4590 * @type: communications type
4591 * @protocol: requested protocol
4592 * @kern: set to 1 if a kernel socket is requested
4593 *
4594 * This hook allows a module to update or allocate a per-socket security
4595 * structure. Note that the security field was not added directly to the socket
4596 * structure, but rather, the socket security information is stored in the
4597 * associated inode. Typically, the inode alloc_security hook will allocate
4598 * and attach security information to SOCK_INODE(sock)->i_security. This hook
4599 * may be used to update the SOCK_INODE(sock)->i_security field with additional
4600 * information that wasn't available when the inode was allocated.
4601 *
4602 * Return: Returns 0 if permission is granted.
4603 */
security_socket_post_create(struct socket * sock,int family,int type,int protocol,int kern)4604 int security_socket_post_create(struct socket *sock, int family,
4605 int type, int protocol, int kern)
4606 {
4607 return call_int_hook(socket_post_create, sock, family, type,
4608 protocol, kern);
4609 }
4610
4611 /**
4612 * security_socket_socketpair() - Check if creating a socketpair is allowed
4613 * @socka: first socket
4614 * @sockb: second socket
4615 *
4616 * Check permissions before creating a fresh pair of sockets.
4617 *
4618 * Return: Returns 0 if permission is granted and the connection was
4619 * established.
4620 */
security_socket_socketpair(struct socket * socka,struct socket * sockb)4621 int security_socket_socketpair(struct socket *socka, struct socket *sockb)
4622 {
4623 return call_int_hook(socket_socketpair, socka, sockb);
4624 }
4625 EXPORT_SYMBOL(security_socket_socketpair);
4626
4627 /**
4628 * security_socket_bind() - Check if a socket bind operation is allowed
4629 * @sock: socket
4630 * @address: requested bind address
4631 * @addrlen: length of address
4632 *
4633 * Check permission before socket protocol layer bind operation is performed
4634 * and the socket @sock is bound to the address specified in the @address
4635 * parameter.
4636 *
4637 * Return: Returns 0 if permission is granted.
4638 */
security_socket_bind(struct socket * sock,struct sockaddr * address,int addrlen)4639 int security_socket_bind(struct socket *sock,
4640 struct sockaddr *address, int addrlen)
4641 {
4642 return call_int_hook(socket_bind, sock, address, addrlen);
4643 }
4644
4645 /**
4646 * security_socket_connect() - Check if a socket connect operation is allowed
4647 * @sock: socket
4648 * @address: address of remote connection point
4649 * @addrlen: length of address
4650 *
4651 * Check permission before socket protocol layer connect operation attempts to
4652 * connect socket @sock to a remote address, @address.
4653 *
4654 * Return: Returns 0 if permission is granted.
4655 */
security_socket_connect(struct socket * sock,struct sockaddr * address,int addrlen)4656 int security_socket_connect(struct socket *sock,
4657 struct sockaddr *address, int addrlen)
4658 {
4659 return call_int_hook(socket_connect, sock, address, addrlen);
4660 }
4661
4662 /**
4663 * security_socket_listen() - Check if a socket is allowed to listen
4664 * @sock: socket
4665 * @backlog: connection queue size
4666 *
4667 * Check permission before socket protocol layer listen operation.
4668 *
4669 * Return: Returns 0 if permission is granted.
4670 */
security_socket_listen(struct socket * sock,int backlog)4671 int security_socket_listen(struct socket *sock, int backlog)
4672 {
4673 return call_int_hook(socket_listen, sock, backlog);
4674 }
4675
4676 /**
4677 * security_socket_accept() - Check if a socket is allowed to accept connections
4678 * @sock: listening socket
4679 * @newsock: newly creation connection socket
4680 *
4681 * Check permission before accepting a new connection. Note that the new
4682 * socket, @newsock, has been created and some information copied to it, but
4683 * the accept operation has not actually been performed.
4684 *
4685 * Return: Returns 0 if permission is granted.
4686 */
security_socket_accept(struct socket * sock,struct socket * newsock)4687 int security_socket_accept(struct socket *sock, struct socket *newsock)
4688 {
4689 return call_int_hook(socket_accept, sock, newsock);
4690 }
4691
4692 /**
4693 * security_socket_sendmsg() - Check if sending a message is allowed
4694 * @sock: sending socket
4695 * @msg: message to send
4696 * @size: size of message
4697 *
4698 * Check permission before transmitting a message to another socket.
4699 *
4700 * Return: Returns 0 if permission is granted.
4701 */
security_socket_sendmsg(struct socket * sock,struct msghdr * msg,int size)4702 int security_socket_sendmsg(struct socket *sock, struct msghdr *msg, int size)
4703 {
4704 return call_int_hook(socket_sendmsg, sock, msg, size);
4705 }
4706
4707 /**
4708 * security_socket_recvmsg() - Check if receiving a message is allowed
4709 * @sock: receiving socket
4710 * @msg: message to receive
4711 * @size: size of message
4712 * @flags: operational flags
4713 *
4714 * Check permission before receiving a message from a socket.
4715 *
4716 * Return: Returns 0 if permission is granted.
4717 */
security_socket_recvmsg(struct socket * sock,struct msghdr * msg,int size,int flags)4718 int security_socket_recvmsg(struct socket *sock, struct msghdr *msg,
4719 int size, int flags)
4720 {
4721 return call_int_hook(socket_recvmsg, sock, msg, size, flags);
4722 }
4723
4724 /**
4725 * security_socket_getsockname() - Check if reading the socket addr is allowed
4726 * @sock: socket
4727 *
4728 * Check permission before reading the local address (name) of the socket
4729 * object.
4730 *
4731 * Return: Returns 0 if permission is granted.
4732 */
security_socket_getsockname(struct socket * sock)4733 int security_socket_getsockname(struct socket *sock)
4734 {
4735 return call_int_hook(socket_getsockname, sock);
4736 }
4737
4738 /**
4739 * security_socket_getpeername() - Check if reading the peer's addr is allowed
4740 * @sock: socket
4741 *
4742 * Check permission before the remote address (name) of a socket object.
4743 *
4744 * Return: Returns 0 if permission is granted.
4745 */
security_socket_getpeername(struct socket * sock)4746 int security_socket_getpeername(struct socket *sock)
4747 {
4748 return call_int_hook(socket_getpeername, sock);
4749 }
4750
4751 /**
4752 * security_socket_getsockopt() - Check if reading a socket option is allowed
4753 * @sock: socket
4754 * @level: option's protocol level
4755 * @optname: option name
4756 *
4757 * Check permissions before retrieving the options associated with socket
4758 * @sock.
4759 *
4760 * Return: Returns 0 if permission is granted.
4761 */
security_socket_getsockopt(struct socket * sock,int level,int optname)4762 int security_socket_getsockopt(struct socket *sock, int level, int optname)
4763 {
4764 return call_int_hook(socket_getsockopt, sock, level, optname);
4765 }
4766
4767 /**
4768 * security_socket_setsockopt() - Check if setting a socket option is allowed
4769 * @sock: socket
4770 * @level: option's protocol level
4771 * @optname: option name
4772 *
4773 * Check permissions before setting the options associated with socket @sock.
4774 *
4775 * Return: Returns 0 if permission is granted.
4776 */
security_socket_setsockopt(struct socket * sock,int level,int optname)4777 int security_socket_setsockopt(struct socket *sock, int level, int optname)
4778 {
4779 return call_int_hook(socket_setsockopt, sock, level, optname);
4780 }
4781
4782 /**
4783 * security_socket_shutdown() - Checks if shutting down the socket is allowed
4784 * @sock: socket
4785 * @how: flag indicating how sends and receives are handled
4786 *
4787 * Checks permission before all or part of a connection on the socket @sock is
4788 * shut down.
4789 *
4790 * Return: Returns 0 if permission is granted.
4791 */
security_socket_shutdown(struct socket * sock,int how)4792 int security_socket_shutdown(struct socket *sock, int how)
4793 {
4794 return call_int_hook(socket_shutdown, sock, how);
4795 }
4796
4797 /**
4798 * security_sock_rcv_skb() - Check if an incoming network packet is allowed
4799 * @sk: destination sock
4800 * @skb: incoming packet
4801 *
4802 * Check permissions on incoming network packets. This hook is distinct from
4803 * Netfilter's IP input hooks since it is the first time that the incoming
4804 * sk_buff @skb has been associated with a particular socket, @sk. Must not
4805 * sleep inside this hook because some callers hold spinlocks.
4806 *
4807 * Return: Returns 0 if permission is granted.
4808 */
security_sock_rcv_skb(struct sock * sk,struct sk_buff * skb)4809 int security_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
4810 {
4811 return call_int_hook(socket_sock_rcv_skb, sk, skb);
4812 }
4813 EXPORT_SYMBOL(security_sock_rcv_skb);
4814
4815 /**
4816 * security_socket_getpeersec_stream() - Get the remote peer label
4817 * @sock: socket
4818 * @optval: destination buffer
4819 * @optlen: size of peer label copied into the buffer
4820 * @len: maximum size of the destination buffer
4821 *
4822 * This hook allows the security module to provide peer socket security state
4823 * for unix or connected tcp sockets to userspace via getsockopt SO_GETPEERSEC.
4824 * For tcp sockets this can be meaningful if the socket is associated with an
4825 * ipsec SA.
4826 *
4827 * Return: Returns 0 if all is well, otherwise, typical getsockopt return
4828 * values.
4829 */
security_socket_getpeersec_stream(struct socket * sock,sockptr_t optval,sockptr_t optlen,unsigned int len)4830 int security_socket_getpeersec_stream(struct socket *sock, sockptr_t optval,
4831 sockptr_t optlen, unsigned int len)
4832 {
4833 return call_int_hook(socket_getpeersec_stream, sock, optval, optlen,
4834 len);
4835 }
4836
4837 /**
4838 * security_socket_getpeersec_dgram() - Get the remote peer label
4839 * @sock: socket
4840 * @skb: datagram packet
4841 * @secid: remote peer label secid
4842 *
4843 * This hook allows the security module to provide peer socket security state
4844 * for udp sockets on a per-packet basis to userspace via getsockopt
4845 * SO_GETPEERSEC. The application must first have indicated the IP_PASSSEC
4846 * option via getsockopt. It can then retrieve the security state returned by
4847 * this hook for a packet via the SCM_SECURITY ancillary message type.
4848 *
4849 * Return: Returns 0 on success, error on failure.
4850 */
security_socket_getpeersec_dgram(struct socket * sock,struct sk_buff * skb,u32 * secid)4851 int security_socket_getpeersec_dgram(struct socket *sock,
4852 struct sk_buff *skb, u32 *secid)
4853 {
4854 return call_int_hook(socket_getpeersec_dgram, sock, skb, secid);
4855 }
4856 EXPORT_SYMBOL(security_socket_getpeersec_dgram);
4857
4858 /**
4859 * lsm_sock_alloc - allocate a composite sock blob
4860 * @sock: the sock that needs a blob
4861 * @gfp: allocation mode
4862 *
4863 * Allocate the sock blob for all the modules
4864 *
4865 * Returns 0, or -ENOMEM if memory can't be allocated.
4866 */
lsm_sock_alloc(struct sock * sock,gfp_t gfp)4867 static int lsm_sock_alloc(struct sock *sock, gfp_t gfp)
4868 {
4869 return lsm_blob_alloc(&sock->sk_security, blob_sizes.lbs_sock, gfp);
4870 }
4871
4872 /**
4873 * security_sk_alloc() - Allocate and initialize a sock's LSM blob
4874 * @sk: sock
4875 * @family: protocol family
4876 * @priority: gfp flags
4877 *
4878 * Allocate and attach a security structure to the sk->sk_security field, which
4879 * is used to copy security attributes between local stream sockets.
4880 *
4881 * Return: Returns 0 on success, error on failure.
4882 */
security_sk_alloc(struct sock * sk,int family,gfp_t priority)4883 int security_sk_alloc(struct sock *sk, int family, gfp_t priority)
4884 {
4885 int rc = lsm_sock_alloc(sk, priority);
4886
4887 if (unlikely(rc))
4888 return rc;
4889 rc = call_int_hook(sk_alloc_security, sk, family, priority);
4890 if (unlikely(rc))
4891 security_sk_free(sk);
4892 return rc;
4893 }
4894
4895 /**
4896 * security_sk_free() - Free the sock's LSM blob
4897 * @sk: sock
4898 *
4899 * Deallocate security structure.
4900 */
security_sk_free(struct sock * sk)4901 void security_sk_free(struct sock *sk)
4902 {
4903 call_void_hook(sk_free_security, sk);
4904 kfree(sk->sk_security);
4905 sk->sk_security = NULL;
4906 }
4907
4908 /**
4909 * security_sk_clone() - Clone a sock's LSM state
4910 * @sk: original sock
4911 * @newsk: target sock
4912 *
4913 * Clone/copy security structure.
4914 */
security_sk_clone(const struct sock * sk,struct sock * newsk)4915 void security_sk_clone(const struct sock *sk, struct sock *newsk)
4916 {
4917 call_void_hook(sk_clone_security, sk, newsk);
4918 }
4919 EXPORT_SYMBOL(security_sk_clone);
4920
4921 /**
4922 * security_sk_classify_flow() - Set a flow's secid based on socket
4923 * @sk: original socket
4924 * @flic: target flow
4925 *
4926 * Set the target flow's secid to socket's secid.
4927 */
security_sk_classify_flow(const struct sock * sk,struct flowi_common * flic)4928 void security_sk_classify_flow(const struct sock *sk, struct flowi_common *flic)
4929 {
4930 call_void_hook(sk_getsecid, sk, &flic->flowic_secid);
4931 }
4932 EXPORT_SYMBOL(security_sk_classify_flow);
4933
4934 /**
4935 * security_req_classify_flow() - Set a flow's secid based on request_sock
4936 * @req: request_sock
4937 * @flic: target flow
4938 *
4939 * Sets @flic's secid to @req's secid.
4940 */
security_req_classify_flow(const struct request_sock * req,struct flowi_common * flic)4941 void security_req_classify_flow(const struct request_sock *req,
4942 struct flowi_common *flic)
4943 {
4944 call_void_hook(req_classify_flow, req, flic);
4945 }
4946 EXPORT_SYMBOL(security_req_classify_flow);
4947
4948 /**
4949 * security_sock_graft() - Reconcile LSM state when grafting a sock on a socket
4950 * @sk: sock being grafted
4951 * @parent: target parent socket
4952 *
4953 * Sets @parent's inode secid to @sk's secid and update @sk with any necessary
4954 * LSM state from @parent.
4955 */
security_sock_graft(struct sock * sk,struct socket * parent)4956 void security_sock_graft(struct sock *sk, struct socket *parent)
4957 {
4958 call_void_hook(sock_graft, sk, parent);
4959 }
4960 EXPORT_SYMBOL(security_sock_graft);
4961
4962 /**
4963 * security_inet_conn_request() - Set request_sock state using incoming connect
4964 * @sk: parent listening sock
4965 * @skb: incoming connection
4966 * @req: new request_sock
4967 *
4968 * Initialize the @req LSM state based on @sk and the incoming connect in @skb.
4969 *
4970 * Return: Returns 0 if permission is granted.
4971 */
security_inet_conn_request(const struct sock * sk,struct sk_buff * skb,struct request_sock * req)4972 int security_inet_conn_request(const struct sock *sk,
4973 struct sk_buff *skb, struct request_sock *req)
4974 {
4975 return call_int_hook(inet_conn_request, sk, skb, req);
4976 }
4977 EXPORT_SYMBOL(security_inet_conn_request);
4978
4979 /**
4980 * security_inet_csk_clone() - Set new sock LSM state based on request_sock
4981 * @newsk: new sock
4982 * @req: connection request_sock
4983 *
4984 * Set that LSM state of @sock using the LSM state from @req.
4985 */
security_inet_csk_clone(struct sock * newsk,const struct request_sock * req)4986 void security_inet_csk_clone(struct sock *newsk,
4987 const struct request_sock *req)
4988 {
4989 call_void_hook(inet_csk_clone, newsk, req);
4990 }
4991
4992 /**
4993 * security_inet_conn_established() - Update sock's LSM state with connection
4994 * @sk: sock
4995 * @skb: connection packet
4996 *
4997 * Update @sock's LSM state to represent a new connection from @skb.
4998 */
security_inet_conn_established(struct sock * sk,struct sk_buff * skb)4999 void security_inet_conn_established(struct sock *sk,
5000 struct sk_buff *skb)
5001 {
5002 call_void_hook(inet_conn_established, sk, skb);
5003 }
5004 EXPORT_SYMBOL(security_inet_conn_established);
5005
5006 /**
5007 * security_secmark_relabel_packet() - Check if setting a secmark is allowed
5008 * @secid: new secmark value
5009 *
5010 * Check if the process should be allowed to relabel packets to @secid.
5011 *
5012 * Return: Returns 0 if permission is granted.
5013 */
security_secmark_relabel_packet(u32 secid)5014 int security_secmark_relabel_packet(u32 secid)
5015 {
5016 return call_int_hook(secmark_relabel_packet, secid);
5017 }
5018 EXPORT_SYMBOL(security_secmark_relabel_packet);
5019
5020 /**
5021 * security_secmark_refcount_inc() - Increment the secmark labeling rule count
5022 *
5023 * Tells the LSM to increment the number of secmark labeling rules loaded.
5024 */
security_secmark_refcount_inc(void)5025 void security_secmark_refcount_inc(void)
5026 {
5027 call_void_hook(secmark_refcount_inc);
5028 }
5029 EXPORT_SYMBOL(security_secmark_refcount_inc);
5030
5031 /**
5032 * security_secmark_refcount_dec() - Decrement the secmark labeling rule count
5033 *
5034 * Tells the LSM to decrement the number of secmark labeling rules loaded.
5035 */
security_secmark_refcount_dec(void)5036 void security_secmark_refcount_dec(void)
5037 {
5038 call_void_hook(secmark_refcount_dec);
5039 }
5040 EXPORT_SYMBOL(security_secmark_refcount_dec);
5041
5042 /**
5043 * security_tun_dev_alloc_security() - Allocate a LSM blob for a TUN device
5044 * @security: pointer to the LSM blob
5045 *
5046 * This hook allows a module to allocate a security structure for a TUN device,
5047 * returning the pointer in @security.
5048 *
5049 * Return: Returns a zero on success, negative values on failure.
5050 */
security_tun_dev_alloc_security(void ** security)5051 int security_tun_dev_alloc_security(void **security)
5052 {
5053 int rc;
5054
5055 rc = lsm_blob_alloc(security, blob_sizes.lbs_tun_dev, GFP_KERNEL);
5056 if (rc)
5057 return rc;
5058
5059 rc = call_int_hook(tun_dev_alloc_security, *security);
5060 if (rc) {
5061 kfree(*security);
5062 *security = NULL;
5063 }
5064 return rc;
5065 }
5066 EXPORT_SYMBOL(security_tun_dev_alloc_security);
5067
5068 /**
5069 * security_tun_dev_free_security() - Free a TUN device LSM blob
5070 * @security: LSM blob
5071 *
5072 * This hook allows a module to free the security structure for a TUN device.
5073 */
security_tun_dev_free_security(void * security)5074 void security_tun_dev_free_security(void *security)
5075 {
5076 kfree(security);
5077 }
5078 EXPORT_SYMBOL(security_tun_dev_free_security);
5079
5080 /**
5081 * security_tun_dev_create() - Check if creating a TUN device is allowed
5082 *
5083 * Check permissions prior to creating a new TUN device.
5084 *
5085 * Return: Returns 0 if permission is granted.
5086 */
security_tun_dev_create(void)5087 int security_tun_dev_create(void)
5088 {
5089 return call_int_hook(tun_dev_create);
5090 }
5091 EXPORT_SYMBOL(security_tun_dev_create);
5092
5093 /**
5094 * security_tun_dev_attach_queue() - Check if attaching a TUN queue is allowed
5095 * @security: TUN device LSM blob
5096 *
5097 * Check permissions prior to attaching to a TUN device queue.
5098 *
5099 * Return: Returns 0 if permission is granted.
5100 */
security_tun_dev_attach_queue(void * security)5101 int security_tun_dev_attach_queue(void *security)
5102 {
5103 return call_int_hook(tun_dev_attach_queue, security);
5104 }
5105 EXPORT_SYMBOL(security_tun_dev_attach_queue);
5106
5107 /**
5108 * security_tun_dev_attach() - Update TUN device LSM state on attach
5109 * @sk: associated sock
5110 * @security: TUN device LSM blob
5111 *
5112 * This hook can be used by the module to update any security state associated
5113 * with the TUN device's sock structure.
5114 *
5115 * Return: Returns 0 if permission is granted.
5116 */
security_tun_dev_attach(struct sock * sk,void * security)5117 int security_tun_dev_attach(struct sock *sk, void *security)
5118 {
5119 return call_int_hook(tun_dev_attach, sk, security);
5120 }
5121 EXPORT_SYMBOL(security_tun_dev_attach);
5122
5123 /**
5124 * security_tun_dev_open() - Update TUN device LSM state on open
5125 * @security: TUN device LSM blob
5126 *
5127 * This hook can be used by the module to update any security state associated
5128 * with the TUN device's security structure.
5129 *
5130 * Return: Returns 0 if permission is granted.
5131 */
security_tun_dev_open(void * security)5132 int security_tun_dev_open(void *security)
5133 {
5134 return call_int_hook(tun_dev_open, security);
5135 }
5136 EXPORT_SYMBOL(security_tun_dev_open);
5137
5138 /**
5139 * security_sctp_assoc_request() - Update the LSM on a SCTP association req
5140 * @asoc: SCTP association
5141 * @skb: packet requesting the association
5142 *
5143 * Passes the @asoc and @chunk->skb of the association INIT packet to the LSM.
5144 *
5145 * Return: Returns 0 on success, error on failure.
5146 */
security_sctp_assoc_request(struct sctp_association * asoc,struct sk_buff * skb)5147 int security_sctp_assoc_request(struct sctp_association *asoc,
5148 struct sk_buff *skb)
5149 {
5150 return call_int_hook(sctp_assoc_request, asoc, skb);
5151 }
5152 EXPORT_SYMBOL(security_sctp_assoc_request);
5153
5154 /**
5155 * security_sctp_bind_connect() - Validate a list of addrs for a SCTP option
5156 * @sk: socket
5157 * @optname: SCTP option to validate
5158 * @address: list of IP addresses to validate
5159 * @addrlen: length of the address list
5160 *
5161 * Validiate permissions required for each address associated with sock @sk.
5162 * Depending on @optname, the addresses will be treated as either a connect or
5163 * bind service. The @addrlen is calculated on each IPv4 and IPv6 address using
5164 * sizeof(struct sockaddr_in) or sizeof(struct sockaddr_in6).
5165 *
5166 * Return: Returns 0 on success, error on failure.
5167 */
security_sctp_bind_connect(struct sock * sk,int optname,struct sockaddr * address,int addrlen)5168 int security_sctp_bind_connect(struct sock *sk, int optname,
5169 struct sockaddr *address, int addrlen)
5170 {
5171 return call_int_hook(sctp_bind_connect, sk, optname, address, addrlen);
5172 }
5173 EXPORT_SYMBOL(security_sctp_bind_connect);
5174
5175 /**
5176 * security_sctp_sk_clone() - Clone a SCTP sock's LSM state
5177 * @asoc: SCTP association
5178 * @sk: original sock
5179 * @newsk: target sock
5180 *
5181 * Called whenever a new socket is created by accept(2) (i.e. a TCP style
5182 * socket) or when a socket is 'peeled off' e.g userspace calls
5183 * sctp_peeloff(3).
5184 */
security_sctp_sk_clone(struct sctp_association * asoc,struct sock * sk,struct sock * newsk)5185 void security_sctp_sk_clone(struct sctp_association *asoc, struct sock *sk,
5186 struct sock *newsk)
5187 {
5188 call_void_hook(sctp_sk_clone, asoc, sk, newsk);
5189 }
5190 EXPORT_SYMBOL(security_sctp_sk_clone);
5191
5192 /**
5193 * security_sctp_assoc_established() - Update LSM state when assoc established
5194 * @asoc: SCTP association
5195 * @skb: packet establishing the association
5196 *
5197 * Passes the @asoc and @chunk->skb of the association COOKIE_ACK packet to the
5198 * security module.
5199 *
5200 * Return: Returns 0 if permission is granted.
5201 */
security_sctp_assoc_established(struct sctp_association * asoc,struct sk_buff * skb)5202 int security_sctp_assoc_established(struct sctp_association *asoc,
5203 struct sk_buff *skb)
5204 {
5205 return call_int_hook(sctp_assoc_established, asoc, skb);
5206 }
5207 EXPORT_SYMBOL(security_sctp_assoc_established);
5208
5209 /**
5210 * security_mptcp_add_subflow() - Inherit the LSM label from the MPTCP socket
5211 * @sk: the owning MPTCP socket
5212 * @ssk: the new subflow
5213 *
5214 * Update the labeling for the given MPTCP subflow, to match the one of the
5215 * owning MPTCP socket. This hook has to be called after the socket creation and
5216 * initialization via the security_socket_create() and
5217 * security_socket_post_create() LSM hooks.
5218 *
5219 * Return: Returns 0 on success or a negative error code on failure.
5220 */
security_mptcp_add_subflow(struct sock * sk,struct sock * ssk)5221 int security_mptcp_add_subflow(struct sock *sk, struct sock *ssk)
5222 {
5223 return call_int_hook(mptcp_add_subflow, sk, ssk);
5224 }
5225
5226 #endif /* CONFIG_SECURITY_NETWORK */
5227
5228 #ifdef CONFIG_SECURITY_INFINIBAND
5229 /**
5230 * security_ib_pkey_access() - Check if access to an IB pkey is allowed
5231 * @sec: LSM blob
5232 * @subnet_prefix: subnet prefix of the port
5233 * @pkey: IB pkey
5234 *
5235 * Check permission to access a pkey when modifying a QP.
5236 *
5237 * Return: Returns 0 if permission is granted.
5238 */
security_ib_pkey_access(void * sec,u64 subnet_prefix,u16 pkey)5239 int security_ib_pkey_access(void *sec, u64 subnet_prefix, u16 pkey)
5240 {
5241 return call_int_hook(ib_pkey_access, sec, subnet_prefix, pkey);
5242 }
5243 EXPORT_SYMBOL(security_ib_pkey_access);
5244
5245 /**
5246 * security_ib_endport_manage_subnet() - Check if SMPs traffic is allowed
5247 * @sec: LSM blob
5248 * @dev_name: IB device name
5249 * @port_num: port number
5250 *
5251 * Check permissions to send and receive SMPs on a end port.
5252 *
5253 * Return: Returns 0 if permission is granted.
5254 */
security_ib_endport_manage_subnet(void * sec,const char * dev_name,u8 port_num)5255 int security_ib_endport_manage_subnet(void *sec,
5256 const char *dev_name, u8 port_num)
5257 {
5258 return call_int_hook(ib_endport_manage_subnet, sec, dev_name, port_num);
5259 }
5260 EXPORT_SYMBOL(security_ib_endport_manage_subnet);
5261
5262 /**
5263 * security_ib_alloc_security() - Allocate an Infiniband LSM blob
5264 * @sec: LSM blob
5265 *
5266 * Allocate a security structure for Infiniband objects.
5267 *
5268 * Return: Returns 0 on success, non-zero on failure.
5269 */
security_ib_alloc_security(void ** sec)5270 int security_ib_alloc_security(void **sec)
5271 {
5272 int rc;
5273
5274 rc = lsm_blob_alloc(sec, blob_sizes.lbs_ib, GFP_KERNEL);
5275 if (rc)
5276 return rc;
5277
5278 rc = call_int_hook(ib_alloc_security, *sec);
5279 if (rc) {
5280 kfree(*sec);
5281 *sec = NULL;
5282 }
5283 return rc;
5284 }
5285 EXPORT_SYMBOL(security_ib_alloc_security);
5286
5287 /**
5288 * security_ib_free_security() - Free an Infiniband LSM blob
5289 * @sec: LSM blob
5290 *
5291 * Deallocate an Infiniband security structure.
5292 */
security_ib_free_security(void * sec)5293 void security_ib_free_security(void *sec)
5294 {
5295 kfree(sec);
5296 }
5297 EXPORT_SYMBOL(security_ib_free_security);
5298 #endif /* CONFIG_SECURITY_INFINIBAND */
5299
5300 #ifdef CONFIG_SECURITY_NETWORK_XFRM
5301 /**
5302 * security_xfrm_policy_alloc() - Allocate a xfrm policy LSM blob
5303 * @ctxp: xfrm security context being added to the SPD
5304 * @sec_ctx: security label provided by userspace
5305 * @gfp: gfp flags
5306 *
5307 * Allocate a security structure to the xp->security field; the security field
5308 * is initialized to NULL when the xfrm_policy is allocated.
5309 *
5310 * Return: Return 0 if operation was successful.
5311 */
security_xfrm_policy_alloc(struct xfrm_sec_ctx ** ctxp,struct xfrm_user_sec_ctx * sec_ctx,gfp_t gfp)5312 int security_xfrm_policy_alloc(struct xfrm_sec_ctx **ctxp,
5313 struct xfrm_user_sec_ctx *sec_ctx,
5314 gfp_t gfp)
5315 {
5316 return call_int_hook(xfrm_policy_alloc_security, ctxp, sec_ctx, gfp);
5317 }
5318 EXPORT_SYMBOL(security_xfrm_policy_alloc);
5319
5320 /**
5321 * security_xfrm_policy_clone() - Clone xfrm policy LSM state
5322 * @old_ctx: xfrm security context
5323 * @new_ctxp: target xfrm security context
5324 *
5325 * Allocate a security structure in new_ctxp that contains the information from
5326 * the old_ctx structure.
5327 *
5328 * Return: Return 0 if operation was successful.
5329 */
security_xfrm_policy_clone(struct xfrm_sec_ctx * old_ctx,struct xfrm_sec_ctx ** new_ctxp)5330 int security_xfrm_policy_clone(struct xfrm_sec_ctx *old_ctx,
5331 struct xfrm_sec_ctx **new_ctxp)
5332 {
5333 return call_int_hook(xfrm_policy_clone_security, old_ctx, new_ctxp);
5334 }
5335
5336 /**
5337 * security_xfrm_policy_free() - Free a xfrm security context
5338 * @ctx: xfrm security context
5339 *
5340 * Free LSM resources associated with @ctx.
5341 */
security_xfrm_policy_free(struct xfrm_sec_ctx * ctx)5342 void security_xfrm_policy_free(struct xfrm_sec_ctx *ctx)
5343 {
5344 call_void_hook(xfrm_policy_free_security, ctx);
5345 }
5346 EXPORT_SYMBOL(security_xfrm_policy_free);
5347
5348 /**
5349 * security_xfrm_policy_delete() - Check if deleting a xfrm policy is allowed
5350 * @ctx: xfrm security context
5351 *
5352 * Authorize deletion of a SPD entry.
5353 *
5354 * Return: Returns 0 if permission is granted.
5355 */
security_xfrm_policy_delete(struct xfrm_sec_ctx * ctx)5356 int security_xfrm_policy_delete(struct xfrm_sec_ctx *ctx)
5357 {
5358 return call_int_hook(xfrm_policy_delete_security, ctx);
5359 }
5360
5361 /**
5362 * security_xfrm_state_alloc() - Allocate a xfrm state LSM blob
5363 * @x: xfrm state being added to the SAD
5364 * @sec_ctx: security label provided by userspace
5365 *
5366 * Allocate a security structure to the @x->security field; the security field
5367 * is initialized to NULL when the xfrm_state is allocated. Set the context to
5368 * correspond to @sec_ctx.
5369 *
5370 * Return: Return 0 if operation was successful.
5371 */
security_xfrm_state_alloc(struct xfrm_state * x,struct xfrm_user_sec_ctx * sec_ctx)5372 int security_xfrm_state_alloc(struct xfrm_state *x,
5373 struct xfrm_user_sec_ctx *sec_ctx)
5374 {
5375 return call_int_hook(xfrm_state_alloc, x, sec_ctx);
5376 }
5377 EXPORT_SYMBOL(security_xfrm_state_alloc);
5378
5379 /**
5380 * security_xfrm_state_alloc_acquire() - Allocate a xfrm state LSM blob
5381 * @x: xfrm state being added to the SAD
5382 * @polsec: associated policy's security context
5383 * @secid: secid from the flow
5384 *
5385 * Allocate a security structure to the x->security field; the security field
5386 * is initialized to NULL when the xfrm_state is allocated. Set the context to
5387 * correspond to secid.
5388 *
5389 * Return: Returns 0 if operation was successful.
5390 */
security_xfrm_state_alloc_acquire(struct xfrm_state * x,struct xfrm_sec_ctx * polsec,u32 secid)5391 int security_xfrm_state_alloc_acquire(struct xfrm_state *x,
5392 struct xfrm_sec_ctx *polsec, u32 secid)
5393 {
5394 return call_int_hook(xfrm_state_alloc_acquire, x, polsec, secid);
5395 }
5396
5397 /**
5398 * security_xfrm_state_delete() - Check if deleting a xfrm state is allowed
5399 * @x: xfrm state
5400 *
5401 * Authorize deletion of x->security.
5402 *
5403 * Return: Returns 0 if permission is granted.
5404 */
security_xfrm_state_delete(struct xfrm_state * x)5405 int security_xfrm_state_delete(struct xfrm_state *x)
5406 {
5407 return call_int_hook(xfrm_state_delete_security, x);
5408 }
5409 EXPORT_SYMBOL(security_xfrm_state_delete);
5410
5411 /**
5412 * security_xfrm_state_free() - Free a xfrm state
5413 * @x: xfrm state
5414 *
5415 * Deallocate x->security.
5416 */
security_xfrm_state_free(struct xfrm_state * x)5417 void security_xfrm_state_free(struct xfrm_state *x)
5418 {
5419 call_void_hook(xfrm_state_free_security, x);
5420 }
5421
5422 /**
5423 * security_xfrm_policy_lookup() - Check if using a xfrm policy is allowed
5424 * @ctx: target xfrm security context
5425 * @fl_secid: flow secid used to authorize access
5426 *
5427 * Check permission when a flow selects a xfrm_policy for processing XFRMs on a
5428 * packet. The hook is called when selecting either a per-socket policy or a
5429 * generic xfrm policy.
5430 *
5431 * Return: Return 0 if permission is granted, -ESRCH otherwise, or -errno on
5432 * other errors.
5433 */
security_xfrm_policy_lookup(struct xfrm_sec_ctx * ctx,u32 fl_secid)5434 int security_xfrm_policy_lookup(struct xfrm_sec_ctx *ctx, u32 fl_secid)
5435 {
5436 return call_int_hook(xfrm_policy_lookup, ctx, fl_secid);
5437 }
5438
5439 /**
5440 * security_xfrm_state_pol_flow_match() - Check for a xfrm match
5441 * @x: xfrm state to match
5442 * @xp: xfrm policy to check for a match
5443 * @flic: flow to check for a match.
5444 *
5445 * Check @xp and @flic for a match with @x.
5446 *
5447 * Return: Returns 1 if there is a match.
5448 */
security_xfrm_state_pol_flow_match(struct xfrm_state * x,struct xfrm_policy * xp,const struct flowi_common * flic)5449 int security_xfrm_state_pol_flow_match(struct xfrm_state *x,
5450 struct xfrm_policy *xp,
5451 const struct flowi_common *flic)
5452 {
5453 struct lsm_static_call *scall;
5454 int rc = LSM_RET_DEFAULT(xfrm_state_pol_flow_match);
5455
5456 /*
5457 * Since this function is expected to return 0 or 1, the judgment
5458 * becomes difficult if multiple LSMs supply this call. Fortunately,
5459 * we can use the first LSM's judgment because currently only SELinux
5460 * supplies this call.
5461 *
5462 * For speed optimization, we explicitly break the loop rather than
5463 * using the macro
5464 */
5465 lsm_for_each_hook(scall, xfrm_state_pol_flow_match) {
5466 rc = scall->hl->hook.xfrm_state_pol_flow_match(x, xp, flic);
5467 break;
5468 }
5469 return rc;
5470 }
5471
5472 /**
5473 * security_xfrm_decode_session() - Determine the xfrm secid for a packet
5474 * @skb: xfrm packet
5475 * @secid: secid
5476 *
5477 * Decode the packet in @skb and return the security label in @secid.
5478 *
5479 * Return: Return 0 if all xfrms used have the same secid.
5480 */
security_xfrm_decode_session(struct sk_buff * skb,u32 * secid)5481 int security_xfrm_decode_session(struct sk_buff *skb, u32 *secid)
5482 {
5483 return call_int_hook(xfrm_decode_session, skb, secid, 1);
5484 }
5485
security_skb_classify_flow(struct sk_buff * skb,struct flowi_common * flic)5486 void security_skb_classify_flow(struct sk_buff *skb, struct flowi_common *flic)
5487 {
5488 int rc = call_int_hook(xfrm_decode_session, skb, &flic->flowic_secid,
5489 0);
5490
5491 BUG_ON(rc);
5492 }
5493 EXPORT_SYMBOL(security_skb_classify_flow);
5494 #endif /* CONFIG_SECURITY_NETWORK_XFRM */
5495
5496 #ifdef CONFIG_KEYS
5497 /**
5498 * security_key_alloc() - Allocate and initialize a kernel key LSM blob
5499 * @key: key
5500 * @cred: credentials
5501 * @flags: allocation flags
5502 *
5503 * Permit allocation of a key and assign security data. Note that key does not
5504 * have a serial number assigned at this point.
5505 *
5506 * Return: Return 0 if permission is granted, -ve error otherwise.
5507 */
security_key_alloc(struct key * key,const struct cred * cred,unsigned long flags)5508 int security_key_alloc(struct key *key, const struct cred *cred,
5509 unsigned long flags)
5510 {
5511 int rc = lsm_key_alloc(key);
5512
5513 if (unlikely(rc))
5514 return rc;
5515 rc = call_int_hook(key_alloc, key, cred, flags);
5516 if (unlikely(rc))
5517 security_key_free(key);
5518 return rc;
5519 }
5520
5521 /**
5522 * security_key_free() - Free a kernel key LSM blob
5523 * @key: key
5524 *
5525 * Notification of destruction; free security data.
5526 */
security_key_free(struct key * key)5527 void security_key_free(struct key *key)
5528 {
5529 kfree(key->security);
5530 key->security = NULL;
5531 }
5532
5533 /**
5534 * security_key_permission() - Check if a kernel key operation is allowed
5535 * @key_ref: key reference
5536 * @cred: credentials of actor requesting access
5537 * @need_perm: requested permissions
5538 *
5539 * See whether a specific operational right is granted to a process on a key.
5540 *
5541 * Return: Return 0 if permission is granted, -ve error otherwise.
5542 */
security_key_permission(key_ref_t key_ref,const struct cred * cred,enum key_need_perm need_perm)5543 int security_key_permission(key_ref_t key_ref, const struct cred *cred,
5544 enum key_need_perm need_perm)
5545 {
5546 return call_int_hook(key_permission, key_ref, cred, need_perm);
5547 }
5548
5549 /**
5550 * security_key_getsecurity() - Get the key's security label
5551 * @key: key
5552 * @buffer: security label buffer
5553 *
5554 * Get a textual representation of the security context attached to a key for
5555 * the purposes of honouring KEYCTL_GETSECURITY. This function allocates the
5556 * storage for the NUL-terminated string and the caller should free it.
5557 *
5558 * Return: Returns the length of @buffer (including terminating NUL) or -ve if
5559 * an error occurs. May also return 0 (and a NULL buffer pointer) if
5560 * there is no security label assigned to the key.
5561 */
security_key_getsecurity(struct key * key,char ** buffer)5562 int security_key_getsecurity(struct key *key, char **buffer)
5563 {
5564 *buffer = NULL;
5565 return call_int_hook(key_getsecurity, key, buffer);
5566 }
5567
5568 /**
5569 * security_key_post_create_or_update() - Notification of key create or update
5570 * @keyring: keyring to which the key is linked to
5571 * @key: created or updated key
5572 * @payload: data used to instantiate or update the key
5573 * @payload_len: length of payload
5574 * @flags: key flags
5575 * @create: flag indicating whether the key was created or updated
5576 *
5577 * Notify the caller of a key creation or update.
5578 */
security_key_post_create_or_update(struct key * keyring,struct key * key,const void * payload,size_t payload_len,unsigned long flags,bool create)5579 void security_key_post_create_or_update(struct key *keyring, struct key *key,
5580 const void *payload, size_t payload_len,
5581 unsigned long flags, bool create)
5582 {
5583 call_void_hook(key_post_create_or_update, keyring, key, payload,
5584 payload_len, flags, create);
5585 }
5586 #endif /* CONFIG_KEYS */
5587
5588 #ifdef CONFIG_AUDIT
5589 /**
5590 * security_audit_rule_init() - Allocate and init an LSM audit rule struct
5591 * @field: audit action
5592 * @op: rule operator
5593 * @rulestr: rule context
5594 * @lsmrule: receive buffer for audit rule struct
5595 * @gfp: GFP flag used for kmalloc
5596 *
5597 * Allocate and initialize an LSM audit rule structure.
5598 *
5599 * Return: Return 0 if @lsmrule has been successfully set, -EINVAL in case of
5600 * an invalid rule.
5601 */
security_audit_rule_init(u32 field,u32 op,char * rulestr,void ** lsmrule,gfp_t gfp)5602 int security_audit_rule_init(u32 field, u32 op, char *rulestr, void **lsmrule,
5603 gfp_t gfp)
5604 {
5605 return call_int_hook(audit_rule_init, field, op, rulestr, lsmrule, gfp);
5606 }
5607
5608 /**
5609 * security_audit_rule_known() - Check if an audit rule contains LSM fields
5610 * @krule: audit rule
5611 *
5612 * Specifies whether given @krule contains any fields related to the current
5613 * LSM.
5614 *
5615 * Return: Returns 1 in case of relation found, 0 otherwise.
5616 */
security_audit_rule_known(struct audit_krule * krule)5617 int security_audit_rule_known(struct audit_krule *krule)
5618 {
5619 return call_int_hook(audit_rule_known, krule);
5620 }
5621
5622 /**
5623 * security_audit_rule_free() - Free an LSM audit rule struct
5624 * @lsmrule: audit rule struct
5625 *
5626 * Deallocate the LSM audit rule structure previously allocated by
5627 * audit_rule_init().
5628 */
security_audit_rule_free(void * lsmrule)5629 void security_audit_rule_free(void *lsmrule)
5630 {
5631 call_void_hook(audit_rule_free, lsmrule);
5632 }
5633
5634 /**
5635 * security_audit_rule_match() - Check if a label matches an audit rule
5636 * @prop: security label
5637 * @field: LSM audit field
5638 * @op: matching operator
5639 * @lsmrule: audit rule
5640 *
5641 * Determine if given @secid matches a rule previously approved by
5642 * security_audit_rule_known().
5643 *
5644 * Return: Returns 1 if secid matches the rule, 0 if it does not, -ERRNO on
5645 * failure.
5646 */
security_audit_rule_match(struct lsm_prop * prop,u32 field,u32 op,void * lsmrule)5647 int security_audit_rule_match(struct lsm_prop *prop, u32 field, u32 op,
5648 void *lsmrule)
5649 {
5650 return call_int_hook(audit_rule_match, prop, field, op, lsmrule);
5651 }
5652 #endif /* CONFIG_AUDIT */
5653
5654 #ifdef CONFIG_BPF_SYSCALL
5655 /**
5656 * security_bpf() - Check if the bpf syscall operation is allowed
5657 * @cmd: command
5658 * @attr: bpf attribute
5659 * @size: size
5660 * @kernel: whether or not call originated from kernel
5661 *
5662 * Do a initial check for all bpf syscalls after the attribute is copied into
5663 * the kernel. The actual security module can implement their own rules to
5664 * check the specific cmd they need.
5665 *
5666 * Return: Returns 0 if permission is granted.
5667 */
security_bpf(int cmd,union bpf_attr * attr,unsigned int size,bool kernel)5668 int security_bpf(int cmd, union bpf_attr *attr, unsigned int size, bool kernel)
5669 {
5670 return call_int_hook(bpf, cmd, attr, size, kernel);
5671 }
5672
5673 /**
5674 * security_bpf_map() - Check if access to a bpf map is allowed
5675 * @map: bpf map
5676 * @fmode: mode
5677 *
5678 * Do a check when the kernel generates and returns a file descriptor for eBPF
5679 * maps.
5680 *
5681 * Return: Returns 0 if permission is granted.
5682 */
security_bpf_map(struct bpf_map * map,fmode_t fmode)5683 int security_bpf_map(struct bpf_map *map, fmode_t fmode)
5684 {
5685 return call_int_hook(bpf_map, map, fmode);
5686 }
5687
5688 /**
5689 * security_bpf_prog() - Check if access to a bpf program is allowed
5690 * @prog: bpf program
5691 *
5692 * Do a check when the kernel generates and returns a file descriptor for eBPF
5693 * programs.
5694 *
5695 * Return: Returns 0 if permission is granted.
5696 */
security_bpf_prog(struct bpf_prog * prog)5697 int security_bpf_prog(struct bpf_prog *prog)
5698 {
5699 return call_int_hook(bpf_prog, prog);
5700 }
5701
5702 /**
5703 * security_bpf_map_create() - Check if BPF map creation is allowed
5704 * @map: BPF map object
5705 * @attr: BPF syscall attributes used to create BPF map
5706 * @token: BPF token used to grant user access
5707 * @kernel: whether or not call originated from kernel
5708 *
5709 * Do a check when the kernel creates a new BPF map. This is also the
5710 * point where LSM blob is allocated for LSMs that need them.
5711 *
5712 * Return: Returns 0 on success, error on failure.
5713 */
security_bpf_map_create(struct bpf_map * map,union bpf_attr * attr,struct bpf_token * token,bool kernel)5714 int security_bpf_map_create(struct bpf_map *map, union bpf_attr *attr,
5715 struct bpf_token *token, bool kernel)
5716 {
5717 return call_int_hook(bpf_map_create, map, attr, token, kernel);
5718 }
5719
5720 /**
5721 * security_bpf_prog_load() - Check if loading of BPF program is allowed
5722 * @prog: BPF program object
5723 * @attr: BPF syscall attributes used to create BPF program
5724 * @token: BPF token used to grant user access to BPF subsystem
5725 * @kernel: whether or not call originated from kernel
5726 *
5727 * Perform an access control check when the kernel loads a BPF program and
5728 * allocates associated BPF program object. This hook is also responsible for
5729 * allocating any required LSM state for the BPF program.
5730 *
5731 * Return: Returns 0 on success, error on failure.
5732 */
security_bpf_prog_load(struct bpf_prog * prog,union bpf_attr * attr,struct bpf_token * token,bool kernel)5733 int security_bpf_prog_load(struct bpf_prog *prog, union bpf_attr *attr,
5734 struct bpf_token *token, bool kernel)
5735 {
5736 return call_int_hook(bpf_prog_load, prog, attr, token, kernel);
5737 }
5738
5739 /**
5740 * security_bpf_token_create() - Check if creating of BPF token is allowed
5741 * @token: BPF token object
5742 * @attr: BPF syscall attributes used to create BPF token
5743 * @path: path pointing to BPF FS mount point from which BPF token is created
5744 *
5745 * Do a check when the kernel instantiates a new BPF token object from BPF FS
5746 * instance. This is also the point where LSM blob can be allocated for LSMs.
5747 *
5748 * Return: Returns 0 on success, error on failure.
5749 */
security_bpf_token_create(struct bpf_token * token,union bpf_attr * attr,const struct path * path)5750 int security_bpf_token_create(struct bpf_token *token, union bpf_attr *attr,
5751 const struct path *path)
5752 {
5753 return call_int_hook(bpf_token_create, token, attr, path);
5754 }
5755
5756 /**
5757 * security_bpf_token_cmd() - Check if BPF token is allowed to delegate
5758 * requested BPF syscall command
5759 * @token: BPF token object
5760 * @cmd: BPF syscall command requested to be delegated by BPF token
5761 *
5762 * Do a check when the kernel decides whether provided BPF token should allow
5763 * delegation of requested BPF syscall command.
5764 *
5765 * Return: Returns 0 on success, error on failure.
5766 */
security_bpf_token_cmd(const struct bpf_token * token,enum bpf_cmd cmd)5767 int security_bpf_token_cmd(const struct bpf_token *token, enum bpf_cmd cmd)
5768 {
5769 return call_int_hook(bpf_token_cmd, token, cmd);
5770 }
5771
5772 /**
5773 * security_bpf_token_capable() - Check if BPF token is allowed to delegate
5774 * requested BPF-related capability
5775 * @token: BPF token object
5776 * @cap: capabilities requested to be delegated by BPF token
5777 *
5778 * Do a check when the kernel decides whether provided BPF token should allow
5779 * delegation of requested BPF-related capabilities.
5780 *
5781 * Return: Returns 0 on success, error on failure.
5782 */
security_bpf_token_capable(const struct bpf_token * token,int cap)5783 int security_bpf_token_capable(const struct bpf_token *token, int cap)
5784 {
5785 return call_int_hook(bpf_token_capable, token, cap);
5786 }
5787
5788 /**
5789 * security_bpf_map_free() - Free a bpf map's LSM blob
5790 * @map: bpf map
5791 *
5792 * Clean up the security information stored inside bpf map.
5793 */
security_bpf_map_free(struct bpf_map * map)5794 void security_bpf_map_free(struct bpf_map *map)
5795 {
5796 call_void_hook(bpf_map_free, map);
5797 }
5798
5799 /**
5800 * security_bpf_prog_free() - Free a BPF program's LSM blob
5801 * @prog: BPF program struct
5802 *
5803 * Clean up the security information stored inside BPF program.
5804 */
security_bpf_prog_free(struct bpf_prog * prog)5805 void security_bpf_prog_free(struct bpf_prog *prog)
5806 {
5807 call_void_hook(bpf_prog_free, prog);
5808 }
5809
5810 /**
5811 * security_bpf_token_free() - Free a BPF token's LSM blob
5812 * @token: BPF token struct
5813 *
5814 * Clean up the security information stored inside BPF token.
5815 */
security_bpf_token_free(struct bpf_token * token)5816 void security_bpf_token_free(struct bpf_token *token)
5817 {
5818 call_void_hook(bpf_token_free, token);
5819 }
5820 #endif /* CONFIG_BPF_SYSCALL */
5821
5822 /**
5823 * security_locked_down() - Check if a kernel feature is allowed
5824 * @what: requested kernel feature
5825 *
5826 * Determine whether a kernel feature that potentially enables arbitrary code
5827 * execution in kernel space should be permitted.
5828 *
5829 * Return: Returns 0 if permission is granted.
5830 */
security_locked_down(enum lockdown_reason what)5831 int security_locked_down(enum lockdown_reason what)
5832 {
5833 return call_int_hook(locked_down, what);
5834 }
5835 EXPORT_SYMBOL(security_locked_down);
5836
5837 /**
5838 * security_bdev_alloc() - Allocate a block device LSM blob
5839 * @bdev: block device
5840 *
5841 * Allocate and attach a security structure to @bdev->bd_security. The
5842 * security field is initialized to NULL when the bdev structure is
5843 * allocated.
5844 *
5845 * Return: Return 0 if operation was successful.
5846 */
security_bdev_alloc(struct block_device * bdev)5847 int security_bdev_alloc(struct block_device *bdev)
5848 {
5849 int rc = 0;
5850
5851 rc = lsm_bdev_alloc(bdev);
5852 if (unlikely(rc))
5853 return rc;
5854
5855 rc = call_int_hook(bdev_alloc_security, bdev);
5856 if (unlikely(rc))
5857 security_bdev_free(bdev);
5858
5859 return rc;
5860 }
5861 EXPORT_SYMBOL(security_bdev_alloc);
5862
5863 /**
5864 * security_bdev_free() - Free a block device's LSM blob
5865 * @bdev: block device
5866 *
5867 * Deallocate the bdev security structure and set @bdev->bd_security to NULL.
5868 */
security_bdev_free(struct block_device * bdev)5869 void security_bdev_free(struct block_device *bdev)
5870 {
5871 if (!bdev->bd_security)
5872 return;
5873
5874 call_void_hook(bdev_free_security, bdev);
5875
5876 kfree(bdev->bd_security);
5877 bdev->bd_security = NULL;
5878 }
5879 EXPORT_SYMBOL(security_bdev_free);
5880
5881 /**
5882 * security_bdev_setintegrity() - Set the device's integrity data
5883 * @bdev: block device
5884 * @type: type of integrity, e.g. hash digest, signature, etc
5885 * @value: the integrity value
5886 * @size: size of the integrity value
5887 *
5888 * Register a verified integrity measurement of a bdev with LSMs.
5889 * LSMs should free the previously saved data if @value is NULL.
5890 * Please note that the new hook should be invoked every time the security
5891 * information is updated to keep these data current. For example, in dm-verity,
5892 * if the mapping table is reloaded and configured to use a different dm-verity
5893 * target with a new roothash and signing information, the previously stored
5894 * data in the LSM blob will become obsolete. It is crucial to re-invoke the
5895 * hook to refresh these data and ensure they are up to date. This necessity
5896 * arises from the design of device-mapper, where a device-mapper device is
5897 * first created, and then targets are subsequently loaded into it. These
5898 * targets can be modified multiple times during the device's lifetime.
5899 * Therefore, while the LSM blob is allocated during the creation of the block
5900 * device, its actual contents are not initialized at this stage and can change
5901 * substantially over time. This includes alterations from data that the LSMs
5902 * 'trusts' to those they do not, making it essential to handle these changes
5903 * correctly. Failure to address this dynamic aspect could potentially allow
5904 * for bypassing LSM checks.
5905 *
5906 * Return: Returns 0 on success, negative values on failure.
5907 */
security_bdev_setintegrity(struct block_device * bdev,enum lsm_integrity_type type,const void * value,size_t size)5908 int security_bdev_setintegrity(struct block_device *bdev,
5909 enum lsm_integrity_type type, const void *value,
5910 size_t size)
5911 {
5912 return call_int_hook(bdev_setintegrity, bdev, type, value, size);
5913 }
5914 EXPORT_SYMBOL(security_bdev_setintegrity);
5915
5916 #ifdef CONFIG_PERF_EVENTS
5917 /**
5918 * security_perf_event_open() - Check if a perf event open is allowed
5919 * @type: type of event
5920 *
5921 * Check whether the @type of perf_event_open syscall is allowed.
5922 *
5923 * Return: Returns 0 if permission is granted.
5924 */
security_perf_event_open(int type)5925 int security_perf_event_open(int type)
5926 {
5927 return call_int_hook(perf_event_open, type);
5928 }
5929
5930 /**
5931 * security_perf_event_alloc() - Allocate a perf event LSM blob
5932 * @event: perf event
5933 *
5934 * Allocate and save perf_event security info.
5935 *
5936 * Return: Returns 0 on success, error on failure.
5937 */
security_perf_event_alloc(struct perf_event * event)5938 int security_perf_event_alloc(struct perf_event *event)
5939 {
5940 int rc;
5941
5942 rc = lsm_blob_alloc(&event->security, blob_sizes.lbs_perf_event,
5943 GFP_KERNEL);
5944 if (rc)
5945 return rc;
5946
5947 rc = call_int_hook(perf_event_alloc, event);
5948 if (rc) {
5949 kfree(event->security);
5950 event->security = NULL;
5951 }
5952 return rc;
5953 }
5954
5955 /**
5956 * security_perf_event_free() - Free a perf event LSM blob
5957 * @event: perf event
5958 *
5959 * Release (free) perf_event security info.
5960 */
security_perf_event_free(struct perf_event * event)5961 void security_perf_event_free(struct perf_event *event)
5962 {
5963 kfree(event->security);
5964 event->security = NULL;
5965 }
5966
5967 /**
5968 * security_perf_event_read() - Check if reading a perf event label is allowed
5969 * @event: perf event
5970 *
5971 * Read perf_event security info if allowed.
5972 *
5973 * Return: Returns 0 if permission is granted.
5974 */
security_perf_event_read(struct perf_event * event)5975 int security_perf_event_read(struct perf_event *event)
5976 {
5977 return call_int_hook(perf_event_read, event);
5978 }
5979
5980 /**
5981 * security_perf_event_write() - Check if writing a perf event label is allowed
5982 * @event: perf event
5983 *
5984 * Write perf_event security info if allowed.
5985 *
5986 * Return: Returns 0 if permission is granted.
5987 */
security_perf_event_write(struct perf_event * event)5988 int security_perf_event_write(struct perf_event *event)
5989 {
5990 return call_int_hook(perf_event_write, event);
5991 }
5992 #endif /* CONFIG_PERF_EVENTS */
5993
5994 #ifdef CONFIG_IO_URING
5995 /**
5996 * security_uring_override_creds() - Check if overriding creds is allowed
5997 * @new: new credentials
5998 *
5999 * Check if the current task, executing an io_uring operation, is allowed to
6000 * override it's credentials with @new.
6001 *
6002 * Return: Returns 0 if permission is granted.
6003 */
security_uring_override_creds(const struct cred * new)6004 int security_uring_override_creds(const struct cred *new)
6005 {
6006 return call_int_hook(uring_override_creds, new);
6007 }
6008
6009 /**
6010 * security_uring_sqpoll() - Check if IORING_SETUP_SQPOLL is allowed
6011 *
6012 * Check whether the current task is allowed to spawn a io_uring polling thread
6013 * (IORING_SETUP_SQPOLL).
6014 *
6015 * Return: Returns 0 if permission is granted.
6016 */
security_uring_sqpoll(void)6017 int security_uring_sqpoll(void)
6018 {
6019 return call_int_hook(uring_sqpoll);
6020 }
6021
6022 /**
6023 * security_uring_cmd() - Check if a io_uring passthrough command is allowed
6024 * @ioucmd: command
6025 *
6026 * Check whether the file_operations uring_cmd is allowed to run.
6027 *
6028 * Return: Returns 0 if permission is granted.
6029 */
security_uring_cmd(struct io_uring_cmd * ioucmd)6030 int security_uring_cmd(struct io_uring_cmd *ioucmd)
6031 {
6032 return call_int_hook(uring_cmd, ioucmd);
6033 }
6034
6035 /**
6036 * security_uring_allowed() - Check if io_uring_setup() is allowed
6037 *
6038 * Check whether the current task is allowed to call io_uring_setup().
6039 *
6040 * Return: Returns 0 if permission is granted.
6041 */
security_uring_allowed(void)6042 int security_uring_allowed(void)
6043 {
6044 return call_int_hook(uring_allowed);
6045 }
6046 #endif /* CONFIG_IO_URING */
6047
6048 /**
6049 * security_initramfs_populated() - Notify LSMs that initramfs has been loaded
6050 *
6051 * Tells the LSMs the initramfs has been unpacked into the rootfs.
6052 */
security_initramfs_populated(void)6053 void security_initramfs_populated(void)
6054 {
6055 call_void_hook(initramfs_populated);
6056 }
6057