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 lsm_set_blob_size(&needed->lbs_bpf_map, &blob_sizes.lbs_bpf_map);
287 lsm_set_blob_size(&needed->lbs_bpf_prog, &blob_sizes.lbs_bpf_prog);
288 lsm_set_blob_size(&needed->lbs_bpf_token, &blob_sizes.lbs_bpf_token);
289 }
290
291 /* Prepare LSM for initialization. */
prepare_lsm(struct lsm_info * lsm)292 static void __init prepare_lsm(struct lsm_info *lsm)
293 {
294 int enabled = lsm_allowed(lsm);
295
296 /* Record enablement (to handle any following exclusive LSMs). */
297 set_enabled(lsm, enabled);
298
299 /* If enabled, do pre-initialization work. */
300 if (enabled) {
301 if ((lsm->flags & LSM_FLAG_EXCLUSIVE) && !exclusive) {
302 exclusive = lsm;
303 init_debug("exclusive chosen: %s\n", lsm->name);
304 }
305
306 lsm_set_blob_sizes(lsm->blobs);
307 }
308 }
309
310 /* Initialize a given LSM, if it is enabled. */
initialize_lsm(struct lsm_info * lsm)311 static void __init initialize_lsm(struct lsm_info *lsm)
312 {
313 if (is_enabled(lsm)) {
314 int ret;
315
316 init_debug("initializing %s\n", lsm->name);
317 ret = lsm->init();
318 WARN(ret, "%s failed to initialize: %d\n", lsm->name, ret);
319 }
320 }
321
322 /*
323 * Current index to use while initializing the lsm id list.
324 */
325 u32 lsm_active_cnt __ro_after_init;
326 const struct lsm_id *lsm_idlist[MAX_LSM_COUNT];
327
328 /* Populate ordered LSMs list from comma-separated LSM name list. */
ordered_lsm_parse(const char * order,const char * origin)329 static void __init ordered_lsm_parse(const char *order, const char *origin)
330 {
331 struct lsm_info *lsm;
332 char *sep, *name, *next;
333
334 /* LSM_ORDER_FIRST is always first. */
335 for (lsm = __start_lsm_info; lsm < __end_lsm_info; lsm++) {
336 if (lsm->order == LSM_ORDER_FIRST)
337 append_ordered_lsm(lsm, " first");
338 }
339
340 /* Process "security=", if given. */
341 if (chosen_major_lsm) {
342 struct lsm_info *major;
343
344 /*
345 * To match the original "security=" behavior, this
346 * explicitly does NOT fallback to another Legacy Major
347 * if the selected one was separately disabled: disable
348 * all non-matching Legacy Major LSMs.
349 */
350 for (major = __start_lsm_info; major < __end_lsm_info;
351 major++) {
352 if ((major->flags & LSM_FLAG_LEGACY_MAJOR) &&
353 strcmp(major->name, chosen_major_lsm) != 0) {
354 set_enabled(major, false);
355 init_debug("security=%s disabled: %s (only one legacy major LSM)\n",
356 chosen_major_lsm, major->name);
357 }
358 }
359 }
360
361 sep = kstrdup(order, GFP_KERNEL);
362 next = sep;
363 /* Walk the list, looking for matching LSMs. */
364 while ((name = strsep(&next, ",")) != NULL) {
365 bool found = false;
366
367 for (lsm = __start_lsm_info; lsm < __end_lsm_info; lsm++) {
368 if (strcmp(lsm->name, name) == 0) {
369 if (lsm->order == LSM_ORDER_MUTABLE)
370 append_ordered_lsm(lsm, origin);
371 found = true;
372 }
373 }
374
375 if (!found)
376 init_debug("%s ignored: %s (not built into kernel)\n",
377 origin, name);
378 }
379
380 /* Process "security=", if given. */
381 if (chosen_major_lsm) {
382 for (lsm = __start_lsm_info; lsm < __end_lsm_info; lsm++) {
383 if (exists_ordered_lsm(lsm))
384 continue;
385 if (strcmp(lsm->name, chosen_major_lsm) == 0)
386 append_ordered_lsm(lsm, "security=");
387 }
388 }
389
390 /* LSM_ORDER_LAST is always last. */
391 for (lsm = __start_lsm_info; lsm < __end_lsm_info; lsm++) {
392 if (lsm->order == LSM_ORDER_LAST)
393 append_ordered_lsm(lsm, " last");
394 }
395
396 /* Disable all LSMs not in the ordered list. */
397 for (lsm = __start_lsm_info; lsm < __end_lsm_info; lsm++) {
398 if (exists_ordered_lsm(lsm))
399 continue;
400 set_enabled(lsm, false);
401 init_debug("%s skipped: %s (not in requested order)\n",
402 origin, lsm->name);
403 }
404
405 kfree(sep);
406 }
407
lsm_static_call_init(struct security_hook_list * hl)408 static void __init lsm_static_call_init(struct security_hook_list *hl)
409 {
410 struct lsm_static_call *scall = hl->scalls;
411 int i;
412
413 for (i = 0; i < MAX_LSM_COUNT; i++) {
414 /* Update the first static call that is not used yet */
415 if (!scall->hl) {
416 __static_call_update(scall->key, scall->trampoline,
417 hl->hook.lsm_func_addr);
418 scall->hl = hl;
419 static_branch_enable(scall->active);
420 return;
421 }
422 scall++;
423 }
424 panic("%s - Ran out of static slots.\n", __func__);
425 }
426
427 static void __init lsm_early_cred(struct cred *cred);
428 static void __init lsm_early_task(struct task_struct *task);
429
430 static int lsm_append(const char *new, char **result);
431
report_lsm_order(void)432 static void __init report_lsm_order(void)
433 {
434 struct lsm_info **lsm, *early;
435 int first = 0;
436
437 pr_info("initializing lsm=");
438
439 /* Report each enabled LSM name, comma separated. */
440 for (early = __start_early_lsm_info;
441 early < __end_early_lsm_info; early++)
442 if (is_enabled(early))
443 pr_cont("%s%s", first++ == 0 ? "" : ",", early->name);
444 for (lsm = ordered_lsms; *lsm; lsm++)
445 if (is_enabled(*lsm))
446 pr_cont("%s%s", first++ == 0 ? "" : ",", (*lsm)->name);
447
448 pr_cont("\n");
449 }
450
ordered_lsm_init(void)451 static void __init ordered_lsm_init(void)
452 {
453 struct lsm_info **lsm;
454
455 if (chosen_lsm_order) {
456 if (chosen_major_lsm) {
457 pr_warn("security=%s is ignored because it is superseded by lsm=%s\n",
458 chosen_major_lsm, chosen_lsm_order);
459 chosen_major_lsm = NULL;
460 }
461 ordered_lsm_parse(chosen_lsm_order, "cmdline");
462 } else
463 ordered_lsm_parse(builtin_lsm_order, "builtin");
464
465 for (lsm = ordered_lsms; *lsm; lsm++)
466 prepare_lsm(*lsm);
467
468 report_lsm_order();
469
470 init_debug("cred blob size = %d\n", blob_sizes.lbs_cred);
471 init_debug("file blob size = %d\n", blob_sizes.lbs_file);
472 init_debug("ib blob size = %d\n", blob_sizes.lbs_ib);
473 init_debug("inode blob size = %d\n", blob_sizes.lbs_inode);
474 init_debug("ipc blob size = %d\n", blob_sizes.lbs_ipc);
475 #ifdef CONFIG_KEYS
476 init_debug("key blob size = %d\n", blob_sizes.lbs_key);
477 #endif /* CONFIG_KEYS */
478 init_debug("msg_msg blob size = %d\n", blob_sizes.lbs_msg_msg);
479 init_debug("sock blob size = %d\n", blob_sizes.lbs_sock);
480 init_debug("superblock blob size = %d\n", blob_sizes.lbs_superblock);
481 init_debug("perf event blob size = %d\n", blob_sizes.lbs_perf_event);
482 init_debug("task blob size = %d\n", blob_sizes.lbs_task);
483 init_debug("tun device blob size = %d\n", blob_sizes.lbs_tun_dev);
484 init_debug("xattr slots = %d\n", blob_sizes.lbs_xattr_count);
485 init_debug("bdev blob size = %d\n", blob_sizes.lbs_bdev);
486 init_debug("bpf map blob size = %d\n", blob_sizes.lbs_bpf_map);
487 init_debug("bpf prog blob size = %d\n", blob_sizes.lbs_bpf_prog);
488 init_debug("bpf token blob size = %d\n", blob_sizes.lbs_bpf_token);
489
490 /*
491 * Create any kmem_caches needed for blobs
492 */
493 if (blob_sizes.lbs_file)
494 lsm_file_cache = kmem_cache_create("lsm_file_cache",
495 blob_sizes.lbs_file, 0,
496 SLAB_PANIC, NULL);
497 if (blob_sizes.lbs_inode)
498 lsm_inode_cache = kmem_cache_create("lsm_inode_cache",
499 blob_sizes.lbs_inode, 0,
500 SLAB_PANIC, NULL);
501
502 lsm_early_cred((struct cred *) current->cred);
503 lsm_early_task(current);
504 for (lsm = ordered_lsms; *lsm; lsm++)
505 initialize_lsm(*lsm);
506 }
507
early_security_init(void)508 int __init early_security_init(void)
509 {
510 struct lsm_info *lsm;
511
512 for (lsm = __start_early_lsm_info; lsm < __end_early_lsm_info; lsm++) {
513 if (!lsm->enabled)
514 lsm->enabled = &lsm_enabled_true;
515 prepare_lsm(lsm);
516 initialize_lsm(lsm);
517 }
518
519 return 0;
520 }
521
522 /**
523 * security_init - initializes the security framework
524 *
525 * This should be called early in the kernel initialization sequence.
526 */
security_init(void)527 int __init security_init(void)
528 {
529 struct lsm_info *lsm;
530
531 init_debug("legacy security=%s\n", chosen_major_lsm ? : " *unspecified*");
532 init_debug(" CONFIG_LSM=%s\n", builtin_lsm_order);
533 init_debug("boot arg lsm=%s\n", chosen_lsm_order ? : " *unspecified*");
534
535 /*
536 * Append the names of the early LSM modules now that kmalloc() is
537 * available
538 */
539 for (lsm = __start_early_lsm_info; lsm < __end_early_lsm_info; lsm++) {
540 init_debug(" early started: %s (%s)\n", lsm->name,
541 is_enabled(lsm) ? "enabled" : "disabled");
542 if (lsm->enabled)
543 lsm_append(lsm->name, &lsm_names);
544 }
545
546 /* Load LSMs in specified order. */
547 ordered_lsm_init();
548
549 return 0;
550 }
551
552 /* Save user chosen LSM */
choose_major_lsm(char * str)553 static int __init choose_major_lsm(char *str)
554 {
555 chosen_major_lsm = str;
556 return 1;
557 }
558 __setup("security=", choose_major_lsm);
559
560 /* Explicitly choose LSM initialization order. */
choose_lsm_order(char * str)561 static int __init choose_lsm_order(char *str)
562 {
563 chosen_lsm_order = str;
564 return 1;
565 }
566 __setup("lsm=", choose_lsm_order);
567
568 /* Enable LSM order debugging. */
enable_debug(char * str)569 static int __init enable_debug(char *str)
570 {
571 debug = true;
572 return 1;
573 }
574 __setup("lsm.debug", enable_debug);
575
match_last_lsm(const char * list,const char * lsm)576 static bool match_last_lsm(const char *list, const char *lsm)
577 {
578 const char *last;
579
580 if (WARN_ON(!list || !lsm))
581 return false;
582 last = strrchr(list, ',');
583 if (last)
584 /* Pass the comma, strcmp() will check for '\0' */
585 last++;
586 else
587 last = list;
588 return !strcmp(last, lsm);
589 }
590
lsm_append(const char * new,char ** result)591 static int lsm_append(const char *new, char **result)
592 {
593 char *cp;
594
595 if (*result == NULL) {
596 *result = kstrdup(new, GFP_KERNEL);
597 if (*result == NULL)
598 return -ENOMEM;
599 } else {
600 /* Check if it is the last registered name */
601 if (match_last_lsm(*result, new))
602 return 0;
603 cp = kasprintf(GFP_KERNEL, "%s,%s", *result, new);
604 if (cp == NULL)
605 return -ENOMEM;
606 kfree(*result);
607 *result = cp;
608 }
609 return 0;
610 }
611
612 /**
613 * security_add_hooks - Add a modules hooks to the hook lists.
614 * @hooks: the hooks to add
615 * @count: the number of hooks to add
616 * @lsmid: the identification information for the security module
617 *
618 * Each LSM has to register its hooks with the infrastructure.
619 */
security_add_hooks(struct security_hook_list * hooks,int count,const struct lsm_id * lsmid)620 void __init security_add_hooks(struct security_hook_list *hooks, int count,
621 const struct lsm_id *lsmid)
622 {
623 int i;
624
625 /*
626 * A security module may call security_add_hooks() more
627 * than once during initialization, and LSM initialization
628 * is serialized. Landlock is one such case.
629 * Look at the previous entry, if there is one, for duplication.
630 */
631 if (lsm_active_cnt == 0 || lsm_idlist[lsm_active_cnt - 1] != lsmid) {
632 if (lsm_active_cnt >= MAX_LSM_COUNT)
633 panic("%s Too many LSMs registered.\n", __func__);
634 lsm_idlist[lsm_active_cnt++] = lsmid;
635 }
636
637 for (i = 0; i < count; i++) {
638 hooks[i].lsmid = lsmid;
639 lsm_static_call_init(&hooks[i]);
640 }
641
642 /*
643 * Don't try to append during early_security_init(), we'll come back
644 * and fix this up afterwards.
645 */
646 if (slab_is_available()) {
647 if (lsm_append(lsmid->name, &lsm_names) < 0)
648 panic("%s - Cannot get early memory.\n", __func__);
649 }
650 }
651
call_blocking_lsm_notifier(enum lsm_event event,void * data)652 int call_blocking_lsm_notifier(enum lsm_event event, void *data)
653 {
654 return blocking_notifier_call_chain(&blocking_lsm_notifier_chain,
655 event, data);
656 }
657 EXPORT_SYMBOL(call_blocking_lsm_notifier);
658
register_blocking_lsm_notifier(struct notifier_block * nb)659 int register_blocking_lsm_notifier(struct notifier_block *nb)
660 {
661 return blocking_notifier_chain_register(&blocking_lsm_notifier_chain,
662 nb);
663 }
664 EXPORT_SYMBOL(register_blocking_lsm_notifier);
665
unregister_blocking_lsm_notifier(struct notifier_block * nb)666 int unregister_blocking_lsm_notifier(struct notifier_block *nb)
667 {
668 return blocking_notifier_chain_unregister(&blocking_lsm_notifier_chain,
669 nb);
670 }
671 EXPORT_SYMBOL(unregister_blocking_lsm_notifier);
672
673 /**
674 * lsm_blob_alloc - allocate a composite blob
675 * @dest: the destination for the blob
676 * @size: the size of the blob
677 * @gfp: allocation type
678 *
679 * Allocate a blob for all the modules
680 *
681 * Returns 0, or -ENOMEM if memory can't be allocated.
682 */
lsm_blob_alloc(void ** dest,size_t size,gfp_t gfp)683 static int lsm_blob_alloc(void **dest, size_t size, gfp_t gfp)
684 {
685 if (size == 0) {
686 *dest = NULL;
687 return 0;
688 }
689
690 *dest = kzalloc(size, gfp);
691 if (*dest == NULL)
692 return -ENOMEM;
693 return 0;
694 }
695
696 /**
697 * lsm_cred_alloc - allocate a composite cred blob
698 * @cred: the cred that needs a blob
699 * @gfp: allocation type
700 *
701 * Allocate the cred blob for all the modules
702 *
703 * Returns 0, or -ENOMEM if memory can't be allocated.
704 */
lsm_cred_alloc(struct cred * cred,gfp_t gfp)705 static int lsm_cred_alloc(struct cred *cred, gfp_t gfp)
706 {
707 return lsm_blob_alloc(&cred->security, blob_sizes.lbs_cred, gfp);
708 }
709
710 /**
711 * lsm_early_cred - during initialization allocate a composite cred blob
712 * @cred: the cred that needs a blob
713 *
714 * Allocate the cred blob for all the modules
715 */
lsm_early_cred(struct cred * cred)716 static void __init lsm_early_cred(struct cred *cred)
717 {
718 int rc = lsm_cred_alloc(cred, GFP_KERNEL);
719
720 if (rc)
721 panic("%s: Early cred alloc failed.\n", __func__);
722 }
723
724 /**
725 * lsm_file_alloc - allocate a composite file blob
726 * @file: the file that needs a blob
727 *
728 * Allocate the file blob for all the modules
729 *
730 * Returns 0, or -ENOMEM if memory can't be allocated.
731 */
lsm_file_alloc(struct file * file)732 static int lsm_file_alloc(struct file *file)
733 {
734 if (!lsm_file_cache) {
735 file->f_security = NULL;
736 return 0;
737 }
738
739 file->f_security = kmem_cache_zalloc(lsm_file_cache, GFP_KERNEL);
740 if (file->f_security == NULL)
741 return -ENOMEM;
742 return 0;
743 }
744
745 /**
746 * lsm_inode_alloc - allocate a composite inode blob
747 * @inode: the inode that needs a blob
748 * @gfp: allocation flags
749 *
750 * Allocate the inode blob for all the modules
751 *
752 * Returns 0, or -ENOMEM if memory can't be allocated.
753 */
lsm_inode_alloc(struct inode * inode,gfp_t gfp)754 static int lsm_inode_alloc(struct inode *inode, gfp_t gfp)
755 {
756 if (!lsm_inode_cache) {
757 inode->i_security = NULL;
758 return 0;
759 }
760
761 inode->i_security = kmem_cache_zalloc(lsm_inode_cache, gfp);
762 if (inode->i_security == NULL)
763 return -ENOMEM;
764 return 0;
765 }
766
767 /**
768 * lsm_task_alloc - allocate a composite task blob
769 * @task: the task that needs a blob
770 *
771 * Allocate the task blob for all the modules
772 *
773 * Returns 0, or -ENOMEM if memory can't be allocated.
774 */
lsm_task_alloc(struct task_struct * task)775 static int lsm_task_alloc(struct task_struct *task)
776 {
777 return lsm_blob_alloc(&task->security, blob_sizes.lbs_task, GFP_KERNEL);
778 }
779
780 /**
781 * lsm_ipc_alloc - allocate a composite ipc blob
782 * @kip: the ipc that needs a blob
783 *
784 * Allocate the ipc blob for all the modules
785 *
786 * Returns 0, or -ENOMEM if memory can't be allocated.
787 */
lsm_ipc_alloc(struct kern_ipc_perm * kip)788 static int lsm_ipc_alloc(struct kern_ipc_perm *kip)
789 {
790 return lsm_blob_alloc(&kip->security, blob_sizes.lbs_ipc, GFP_KERNEL);
791 }
792
793 #ifdef CONFIG_KEYS
794 /**
795 * lsm_key_alloc - allocate a composite key blob
796 * @key: the key that needs a blob
797 *
798 * Allocate the key blob for all the modules
799 *
800 * Returns 0, or -ENOMEM if memory can't be allocated.
801 */
lsm_key_alloc(struct key * key)802 static int lsm_key_alloc(struct key *key)
803 {
804 return lsm_blob_alloc(&key->security, blob_sizes.lbs_key, GFP_KERNEL);
805 }
806 #endif /* CONFIG_KEYS */
807
808 /**
809 * lsm_msg_msg_alloc - allocate a composite msg_msg blob
810 * @mp: the msg_msg that needs a blob
811 *
812 * Allocate the ipc blob for all the modules
813 *
814 * Returns 0, or -ENOMEM if memory can't be allocated.
815 */
lsm_msg_msg_alloc(struct msg_msg * mp)816 static int lsm_msg_msg_alloc(struct msg_msg *mp)
817 {
818 return lsm_blob_alloc(&mp->security, blob_sizes.lbs_msg_msg,
819 GFP_KERNEL);
820 }
821
822 /**
823 * lsm_bdev_alloc - allocate a composite block_device blob
824 * @bdev: the block_device that needs a blob
825 *
826 * Allocate the block_device blob for all the modules
827 *
828 * Returns 0, or -ENOMEM if memory can't be allocated.
829 */
lsm_bdev_alloc(struct block_device * bdev)830 static int lsm_bdev_alloc(struct block_device *bdev)
831 {
832 return lsm_blob_alloc(&bdev->bd_security, blob_sizes.lbs_bdev,
833 GFP_KERNEL);
834 }
835
836 #ifdef CONFIG_BPF_SYSCALL
837 /**
838 * lsm_bpf_map_alloc - allocate a composite bpf_map blob
839 * @map: the bpf_map that needs a blob
840 *
841 * Allocate the bpf_map blob for all the modules
842 *
843 * Returns 0, or -ENOMEM if memory can't be allocated.
844 */
lsm_bpf_map_alloc(struct bpf_map * map)845 static int lsm_bpf_map_alloc(struct bpf_map *map)
846 {
847 return lsm_blob_alloc(&map->security, blob_sizes.lbs_bpf_map, GFP_KERNEL);
848 }
849
850 /**
851 * lsm_bpf_prog_alloc - allocate a composite bpf_prog blob
852 * @prog: the bpf_prog that needs a blob
853 *
854 * Allocate the bpf_prog blob for all the modules
855 *
856 * Returns 0, or -ENOMEM if memory can't be allocated.
857 */
lsm_bpf_prog_alloc(struct bpf_prog * prog)858 static int lsm_bpf_prog_alloc(struct bpf_prog *prog)
859 {
860 return lsm_blob_alloc(&prog->aux->security, blob_sizes.lbs_bpf_prog, GFP_KERNEL);
861 }
862
863 /**
864 * lsm_bpf_token_alloc - allocate a composite bpf_token blob
865 * @token: the bpf_token that needs a blob
866 *
867 * Allocate the bpf_token blob for all the modules
868 *
869 * Returns 0, or -ENOMEM if memory can't be allocated.
870 */
lsm_bpf_token_alloc(struct bpf_token * token)871 static int lsm_bpf_token_alloc(struct bpf_token *token)
872 {
873 return lsm_blob_alloc(&token->security, blob_sizes.lbs_bpf_token, GFP_KERNEL);
874 }
875 #endif /* CONFIG_BPF_SYSCALL */
876
877 /**
878 * lsm_early_task - during initialization allocate a composite task blob
879 * @task: the task that needs a blob
880 *
881 * Allocate the task blob for all the modules
882 */
lsm_early_task(struct task_struct * task)883 static void __init lsm_early_task(struct task_struct *task)
884 {
885 int rc = lsm_task_alloc(task);
886
887 if (rc)
888 panic("%s: Early task alloc failed.\n", __func__);
889 }
890
891 /**
892 * lsm_superblock_alloc - allocate a composite superblock blob
893 * @sb: the superblock that needs a blob
894 *
895 * Allocate the superblock blob for all the modules
896 *
897 * Returns 0, or -ENOMEM if memory can't be allocated.
898 */
lsm_superblock_alloc(struct super_block * sb)899 static int lsm_superblock_alloc(struct super_block *sb)
900 {
901 return lsm_blob_alloc(&sb->s_security, blob_sizes.lbs_superblock,
902 GFP_KERNEL);
903 }
904
905 /**
906 * lsm_fill_user_ctx - Fill a user space lsm_ctx structure
907 * @uctx: a userspace LSM context to be filled
908 * @uctx_len: available uctx size (input), used uctx size (output)
909 * @val: the new LSM context value
910 * @val_len: the size of the new LSM context value
911 * @id: LSM id
912 * @flags: LSM defined flags
913 *
914 * Fill all of the fields in a userspace lsm_ctx structure. If @uctx is NULL
915 * simply calculate the required size to output via @utc_len and return
916 * success.
917 *
918 * Returns 0 on success, -E2BIG if userspace buffer is not large enough,
919 * -EFAULT on a copyout error, -ENOMEM if memory can't be allocated.
920 */
lsm_fill_user_ctx(struct lsm_ctx __user * uctx,u32 * uctx_len,void * val,size_t val_len,u64 id,u64 flags)921 int lsm_fill_user_ctx(struct lsm_ctx __user *uctx, u32 *uctx_len,
922 void *val, size_t val_len,
923 u64 id, u64 flags)
924 {
925 struct lsm_ctx *nctx = NULL;
926 size_t nctx_len;
927 int rc = 0;
928
929 nctx_len = ALIGN(struct_size(nctx, ctx, val_len), sizeof(void *));
930 if (nctx_len > *uctx_len) {
931 rc = -E2BIG;
932 goto out;
933 }
934
935 /* no buffer - return success/0 and set @uctx_len to the req size */
936 if (!uctx)
937 goto out;
938
939 nctx = kzalloc(nctx_len, GFP_KERNEL);
940 if (nctx == NULL) {
941 rc = -ENOMEM;
942 goto out;
943 }
944 nctx->id = id;
945 nctx->flags = flags;
946 nctx->len = nctx_len;
947 nctx->ctx_len = val_len;
948 memcpy(nctx->ctx, val, val_len);
949
950 if (copy_to_user(uctx, nctx, nctx_len))
951 rc = -EFAULT;
952
953 out:
954 kfree(nctx);
955 *uctx_len = nctx_len;
956 return rc;
957 }
958
959 /*
960 * The default value of the LSM hook is defined in linux/lsm_hook_defs.h and
961 * can be accessed with:
962 *
963 * LSM_RET_DEFAULT(<hook_name>)
964 *
965 * The macros below define static constants for the default value of each
966 * LSM hook.
967 */
968 #define LSM_RET_DEFAULT(NAME) (NAME##_default)
969 #define DECLARE_LSM_RET_DEFAULT_void(DEFAULT, NAME)
970 #define DECLARE_LSM_RET_DEFAULT_int(DEFAULT, NAME) \
971 static const int __maybe_unused LSM_RET_DEFAULT(NAME) = (DEFAULT);
972 #define LSM_HOOK(RET, DEFAULT, NAME, ...) \
973 DECLARE_LSM_RET_DEFAULT_##RET(DEFAULT, NAME)
974
975 #include <linux/lsm_hook_defs.h>
976 #undef LSM_HOOK
977
978 /*
979 * Hook list operation macros.
980 *
981 * call_void_hook:
982 * This is a hook that does not return a value.
983 *
984 * call_int_hook:
985 * This is a hook that returns a value.
986 */
987 #define __CALL_STATIC_VOID(NUM, HOOK, ...) \
988 do { \
989 if (static_branch_unlikely(&SECURITY_HOOK_ACTIVE_KEY(HOOK, NUM))) { \
990 static_call(LSM_STATIC_CALL(HOOK, NUM))(__VA_ARGS__); \
991 } \
992 } while (0);
993
994 #define call_void_hook(HOOK, ...) \
995 do { \
996 LSM_LOOP_UNROLL(__CALL_STATIC_VOID, HOOK, __VA_ARGS__); \
997 } while (0)
998
999
1000 #define __CALL_STATIC_INT(NUM, R, HOOK, LABEL, ...) \
1001 do { \
1002 if (static_branch_unlikely(&SECURITY_HOOK_ACTIVE_KEY(HOOK, NUM))) { \
1003 R = static_call(LSM_STATIC_CALL(HOOK, NUM))(__VA_ARGS__); \
1004 if (R != LSM_RET_DEFAULT(HOOK)) \
1005 goto LABEL; \
1006 } \
1007 } while (0);
1008
1009 #define call_int_hook(HOOK, ...) \
1010 ({ \
1011 __label__ OUT; \
1012 int RC = LSM_RET_DEFAULT(HOOK); \
1013 \
1014 LSM_LOOP_UNROLL(__CALL_STATIC_INT, RC, HOOK, OUT, __VA_ARGS__); \
1015 OUT: \
1016 RC; \
1017 })
1018
1019 #define lsm_for_each_hook(scall, NAME) \
1020 for (scall = static_calls_table.NAME; \
1021 scall - static_calls_table.NAME < MAX_LSM_COUNT; scall++) \
1022 if (static_key_enabled(&scall->active->key))
1023
1024 /* Security operations */
1025
1026 /**
1027 * security_binder_set_context_mgr() - Check if becoming binder ctx mgr is ok
1028 * @mgr: task credentials of current binder process
1029 *
1030 * Check whether @mgr is allowed to be the binder context manager.
1031 *
1032 * Return: Return 0 if permission is granted.
1033 */
security_binder_set_context_mgr(const struct cred * mgr)1034 int security_binder_set_context_mgr(const struct cred *mgr)
1035 {
1036 return call_int_hook(binder_set_context_mgr, mgr);
1037 }
1038
1039 /**
1040 * security_binder_transaction() - Check if a binder transaction is allowed
1041 * @from: sending process
1042 * @to: receiving process
1043 *
1044 * Check whether @from is allowed to invoke a binder transaction call to @to.
1045 *
1046 * Return: Returns 0 if permission is granted.
1047 */
security_binder_transaction(const struct cred * from,const struct cred * to)1048 int security_binder_transaction(const struct cred *from,
1049 const struct cred *to)
1050 {
1051 return call_int_hook(binder_transaction, from, to);
1052 }
1053
1054 /**
1055 * security_binder_transfer_binder() - Check if a binder transfer is allowed
1056 * @from: sending process
1057 * @to: receiving process
1058 *
1059 * Check whether @from is allowed to transfer a binder reference to @to.
1060 *
1061 * Return: Returns 0 if permission is granted.
1062 */
security_binder_transfer_binder(const struct cred * from,const struct cred * to)1063 int security_binder_transfer_binder(const struct cred *from,
1064 const struct cred *to)
1065 {
1066 return call_int_hook(binder_transfer_binder, from, to);
1067 }
1068
1069 /**
1070 * security_binder_transfer_file() - Check if a binder file xfer is allowed
1071 * @from: sending process
1072 * @to: receiving process
1073 * @file: file being transferred
1074 *
1075 * Check whether @from is allowed to transfer @file to @to.
1076 *
1077 * Return: Returns 0 if permission is granted.
1078 */
security_binder_transfer_file(const struct cred * from,const struct cred * to,const struct file * file)1079 int security_binder_transfer_file(const struct cred *from,
1080 const struct cred *to, const struct file *file)
1081 {
1082 return call_int_hook(binder_transfer_file, from, to, file);
1083 }
1084
1085 /**
1086 * security_ptrace_access_check() - Check if tracing is allowed
1087 * @child: target process
1088 * @mode: PTRACE_MODE flags
1089 *
1090 * Check permission before allowing the current process to trace the @child
1091 * process. Security modules may also want to perform a process tracing check
1092 * during an execve in the set_security or apply_creds hooks of tracing check
1093 * during an execve in the bprm_set_creds hook of binprm_security_ops if the
1094 * process is being traced and its security attributes would be changed by the
1095 * execve.
1096 *
1097 * Return: Returns 0 if permission is granted.
1098 */
security_ptrace_access_check(struct task_struct * child,unsigned int mode)1099 int security_ptrace_access_check(struct task_struct *child, unsigned int mode)
1100 {
1101 return call_int_hook(ptrace_access_check, child, mode);
1102 }
1103
1104 /**
1105 * security_ptrace_traceme() - Check if tracing is allowed
1106 * @parent: tracing process
1107 *
1108 * Check that the @parent process has sufficient permission to trace the
1109 * current process before allowing the current process to present itself to the
1110 * @parent process for tracing.
1111 *
1112 * Return: Returns 0 if permission is granted.
1113 */
security_ptrace_traceme(struct task_struct * parent)1114 int security_ptrace_traceme(struct task_struct *parent)
1115 {
1116 return call_int_hook(ptrace_traceme, parent);
1117 }
1118
1119 /**
1120 * security_capget() - Get the capability sets for a process
1121 * @target: target process
1122 * @effective: effective capability set
1123 * @inheritable: inheritable capability set
1124 * @permitted: permitted capability set
1125 *
1126 * Get the @effective, @inheritable, and @permitted capability sets for the
1127 * @target process. The hook may also perform permission checking to determine
1128 * if the current process is allowed to see the capability sets of the @target
1129 * process.
1130 *
1131 * Return: Returns 0 if the capability sets were successfully obtained.
1132 */
security_capget(const struct task_struct * target,kernel_cap_t * effective,kernel_cap_t * inheritable,kernel_cap_t * permitted)1133 int security_capget(const struct task_struct *target,
1134 kernel_cap_t *effective,
1135 kernel_cap_t *inheritable,
1136 kernel_cap_t *permitted)
1137 {
1138 return call_int_hook(capget, target, effective, inheritable, permitted);
1139 }
1140
1141 /**
1142 * security_capset() - Set the capability sets for a process
1143 * @new: new credentials for the target process
1144 * @old: current credentials of the target process
1145 * @effective: effective capability set
1146 * @inheritable: inheritable capability set
1147 * @permitted: permitted capability set
1148 *
1149 * Set the @effective, @inheritable, and @permitted capability sets for the
1150 * current process.
1151 *
1152 * Return: Returns 0 and update @new if permission is granted.
1153 */
security_capset(struct cred * new,const struct cred * old,const kernel_cap_t * effective,const kernel_cap_t * inheritable,const kernel_cap_t * permitted)1154 int security_capset(struct cred *new, const struct cred *old,
1155 const kernel_cap_t *effective,
1156 const kernel_cap_t *inheritable,
1157 const kernel_cap_t *permitted)
1158 {
1159 return call_int_hook(capset, new, old, effective, inheritable,
1160 permitted);
1161 }
1162
1163 /**
1164 * security_capable() - Check if a process has the necessary capability
1165 * @cred: credentials to examine
1166 * @ns: user namespace
1167 * @cap: capability requested
1168 * @opts: capability check options
1169 *
1170 * Check whether the @tsk process has the @cap capability in the indicated
1171 * credentials. @cap contains the capability <include/linux/capability.h>.
1172 * @opts contains options for the capable check <include/linux/security.h>.
1173 *
1174 * Return: Returns 0 if the capability is granted.
1175 */
security_capable(const struct cred * cred,struct user_namespace * ns,int cap,unsigned int opts)1176 int security_capable(const struct cred *cred,
1177 struct user_namespace *ns,
1178 int cap,
1179 unsigned int opts)
1180 {
1181 return call_int_hook(capable, cred, ns, cap, opts);
1182 }
1183
1184 /**
1185 * security_quotactl() - Check if a quotactl() syscall is allowed for this fs
1186 * @cmds: commands
1187 * @type: type
1188 * @id: id
1189 * @sb: filesystem
1190 *
1191 * Check whether the quotactl syscall is allowed for this @sb.
1192 *
1193 * Return: Returns 0 if permission is granted.
1194 */
security_quotactl(int cmds,int type,int id,const struct super_block * sb)1195 int security_quotactl(int cmds, int type, int id, const struct super_block *sb)
1196 {
1197 return call_int_hook(quotactl, cmds, type, id, sb);
1198 }
1199
1200 /**
1201 * security_quota_on() - Check if QUOTAON is allowed for a dentry
1202 * @dentry: dentry
1203 *
1204 * Check whether QUOTAON is allowed for @dentry.
1205 *
1206 * Return: Returns 0 if permission is granted.
1207 */
security_quota_on(struct dentry * dentry)1208 int security_quota_on(struct dentry *dentry)
1209 {
1210 return call_int_hook(quota_on, dentry);
1211 }
1212
1213 /**
1214 * security_syslog() - Check if accessing the kernel message ring is allowed
1215 * @type: SYSLOG_ACTION_* type
1216 *
1217 * Check permission before accessing the kernel message ring or changing
1218 * logging to the console. See the syslog(2) manual page for an explanation of
1219 * the @type values.
1220 *
1221 * Return: Return 0 if permission is granted.
1222 */
security_syslog(int type)1223 int security_syslog(int type)
1224 {
1225 return call_int_hook(syslog, type);
1226 }
1227
1228 /**
1229 * security_settime64() - Check if changing the system time is allowed
1230 * @ts: new time
1231 * @tz: timezone
1232 *
1233 * Check permission to change the system time, struct timespec64 is defined in
1234 * <include/linux/time64.h> and timezone is defined in <include/linux/time.h>.
1235 *
1236 * Return: Returns 0 if permission is granted.
1237 */
security_settime64(const struct timespec64 * ts,const struct timezone * tz)1238 int security_settime64(const struct timespec64 *ts, const struct timezone *tz)
1239 {
1240 return call_int_hook(settime, ts, tz);
1241 }
1242
1243 /**
1244 * security_vm_enough_memory_mm() - Check if allocating a new mem map is allowed
1245 * @mm: mm struct
1246 * @pages: number of pages
1247 *
1248 * Check permissions for allocating a new virtual mapping. If all LSMs return
1249 * a positive value, __vm_enough_memory() will be called with cap_sys_admin
1250 * set. If at least one LSM returns 0 or negative, __vm_enough_memory() will be
1251 * called with cap_sys_admin cleared.
1252 *
1253 * Return: Returns 0 if permission is granted by the LSM infrastructure to the
1254 * caller.
1255 */
security_vm_enough_memory_mm(struct mm_struct * mm,long pages)1256 int security_vm_enough_memory_mm(struct mm_struct *mm, long pages)
1257 {
1258 struct lsm_static_call *scall;
1259 int cap_sys_admin = 1;
1260 int rc;
1261
1262 /*
1263 * The module will respond with 0 if it thinks the __vm_enough_memory()
1264 * call should be made with the cap_sys_admin set. If all of the modules
1265 * agree that it should be set it will. If any module thinks it should
1266 * not be set it won't.
1267 */
1268 lsm_for_each_hook(scall, vm_enough_memory) {
1269 rc = scall->hl->hook.vm_enough_memory(mm, pages);
1270 if (rc < 0) {
1271 cap_sys_admin = 0;
1272 break;
1273 }
1274 }
1275 return __vm_enough_memory(mm, pages, cap_sys_admin);
1276 }
1277
1278 /**
1279 * security_bprm_creds_for_exec() - Prepare the credentials for exec()
1280 * @bprm: binary program information
1281 *
1282 * If the setup in prepare_exec_creds did not setup @bprm->cred->security
1283 * properly for executing @bprm->file, update the LSM's portion of
1284 * @bprm->cred->security to be what commit_creds needs to install for the new
1285 * program. This hook may also optionally check permissions (e.g. for
1286 * transitions between security domains). The hook must set @bprm->secureexec
1287 * to 1 if AT_SECURE should be set to request libc enable secure mode. @bprm
1288 * contains the linux_binprm structure.
1289 *
1290 * If execveat(2) is called with the AT_EXECVE_CHECK flag, bprm->is_check is
1291 * set. The result must be the same as without this flag even if the execution
1292 * will never really happen and @bprm will always be dropped.
1293 *
1294 * This hook must not change current->cred, only @bprm->cred.
1295 *
1296 * Return: Returns 0 if the hook is successful and permission is granted.
1297 */
security_bprm_creds_for_exec(struct linux_binprm * bprm)1298 int security_bprm_creds_for_exec(struct linux_binprm *bprm)
1299 {
1300 return call_int_hook(bprm_creds_for_exec, bprm);
1301 }
1302
1303 /**
1304 * security_bprm_creds_from_file() - Update linux_binprm creds based on file
1305 * @bprm: binary program information
1306 * @file: associated file
1307 *
1308 * If @file is setpcap, suid, sgid or otherwise marked to change privilege upon
1309 * exec, update @bprm->cred to reflect that change. This is called after
1310 * finding the binary that will be executed without an interpreter. This
1311 * ensures that the credentials will not be derived from a script that the
1312 * binary will need to reopen, which when reopend may end up being a completely
1313 * different file. This hook may also optionally check permissions (e.g. for
1314 * transitions between security domains). The hook must set @bprm->secureexec
1315 * to 1 if AT_SECURE should be set to request libc enable secure mode. The
1316 * hook must add to @bprm->per_clear any personality flags that should be
1317 * cleared from current->personality. @bprm contains the linux_binprm
1318 * structure.
1319 *
1320 * Return: Returns 0 if the hook is successful and permission is granted.
1321 */
security_bprm_creds_from_file(struct linux_binprm * bprm,const struct file * file)1322 int security_bprm_creds_from_file(struct linux_binprm *bprm, const struct file *file)
1323 {
1324 return call_int_hook(bprm_creds_from_file, bprm, file);
1325 }
1326
1327 /**
1328 * security_bprm_check() - Mediate binary handler search
1329 * @bprm: binary program information
1330 *
1331 * This hook mediates the point when a search for a binary handler will begin.
1332 * It allows a check against the @bprm->cred->security value which was set in
1333 * the preceding creds_for_exec call. The argv list and envp list are reliably
1334 * available in @bprm. This hook may be called multiple times during a single
1335 * execve. @bprm contains the linux_binprm structure.
1336 *
1337 * Return: Returns 0 if the hook is successful and permission is granted.
1338 */
security_bprm_check(struct linux_binprm * bprm)1339 int security_bprm_check(struct linux_binprm *bprm)
1340 {
1341 return call_int_hook(bprm_check_security, bprm);
1342 }
1343
1344 /**
1345 * security_bprm_committing_creds() - Install creds for a process during exec()
1346 * @bprm: binary program information
1347 *
1348 * Prepare to install the new security attributes of a process being
1349 * transformed by an execve operation, based on the old credentials pointed to
1350 * by @current->cred and the information set in @bprm->cred by the
1351 * bprm_creds_for_exec hook. @bprm points to the linux_binprm structure. This
1352 * hook is a good place to perform state changes on the process such as closing
1353 * open file descriptors to which access will no longer be granted when the
1354 * attributes are changed. This is called immediately before commit_creds().
1355 */
security_bprm_committing_creds(const struct linux_binprm * bprm)1356 void security_bprm_committing_creds(const struct linux_binprm *bprm)
1357 {
1358 call_void_hook(bprm_committing_creds, bprm);
1359 }
1360
1361 /**
1362 * security_bprm_committed_creds() - Tidy up after cred install during exec()
1363 * @bprm: binary program information
1364 *
1365 * Tidy up after the installation of the new security attributes of a process
1366 * being transformed by an execve operation. The new credentials have, by this
1367 * point, been set to @current->cred. @bprm points to the linux_binprm
1368 * structure. This hook is a good place to perform state changes on the
1369 * process such as clearing out non-inheritable signal state. This is called
1370 * immediately after commit_creds().
1371 */
security_bprm_committed_creds(const struct linux_binprm * bprm)1372 void security_bprm_committed_creds(const struct linux_binprm *bprm)
1373 {
1374 call_void_hook(bprm_committed_creds, bprm);
1375 }
1376
1377 /**
1378 * security_fs_context_submount() - Initialise fc->security
1379 * @fc: new filesystem context
1380 * @reference: dentry reference for submount/remount
1381 *
1382 * Fill out the ->security field for a new fs_context.
1383 *
1384 * Return: Returns 0 on success or negative error code on failure.
1385 */
security_fs_context_submount(struct fs_context * fc,struct super_block * reference)1386 int security_fs_context_submount(struct fs_context *fc, struct super_block *reference)
1387 {
1388 return call_int_hook(fs_context_submount, fc, reference);
1389 }
1390
1391 /**
1392 * security_fs_context_dup() - Duplicate a fs_context LSM blob
1393 * @fc: destination filesystem context
1394 * @src_fc: source filesystem context
1395 *
1396 * Allocate and attach a security structure to sc->security. This pointer is
1397 * initialised to NULL by the caller. @fc indicates the new filesystem context.
1398 * @src_fc indicates the original filesystem context.
1399 *
1400 * Return: Returns 0 on success or a negative error code on failure.
1401 */
security_fs_context_dup(struct fs_context * fc,struct fs_context * src_fc)1402 int security_fs_context_dup(struct fs_context *fc, struct fs_context *src_fc)
1403 {
1404 return call_int_hook(fs_context_dup, fc, src_fc);
1405 }
1406
1407 /**
1408 * security_fs_context_parse_param() - Configure a filesystem context
1409 * @fc: filesystem context
1410 * @param: filesystem parameter
1411 *
1412 * Userspace provided a parameter to configure a superblock. The LSM can
1413 * consume the parameter or return it to the caller for use elsewhere.
1414 *
1415 * Return: If the parameter is used by the LSM it should return 0, if it is
1416 * returned to the caller -ENOPARAM is returned, otherwise a negative
1417 * error code is returned.
1418 */
security_fs_context_parse_param(struct fs_context * fc,struct fs_parameter * param)1419 int security_fs_context_parse_param(struct fs_context *fc,
1420 struct fs_parameter *param)
1421 {
1422 struct lsm_static_call *scall;
1423 int trc;
1424 int rc = -ENOPARAM;
1425
1426 lsm_for_each_hook(scall, fs_context_parse_param) {
1427 trc = scall->hl->hook.fs_context_parse_param(fc, param);
1428 if (trc == 0)
1429 rc = 0;
1430 else if (trc != -ENOPARAM)
1431 return trc;
1432 }
1433 return rc;
1434 }
1435
1436 /**
1437 * security_sb_alloc() - Allocate a super_block LSM blob
1438 * @sb: filesystem superblock
1439 *
1440 * Allocate and attach a security structure to the sb->s_security field. The
1441 * s_security field is initialized to NULL when the structure is allocated.
1442 * @sb contains the super_block structure to be modified.
1443 *
1444 * Return: Returns 0 if operation was successful.
1445 */
security_sb_alloc(struct super_block * sb)1446 int security_sb_alloc(struct super_block *sb)
1447 {
1448 int rc = lsm_superblock_alloc(sb);
1449
1450 if (unlikely(rc))
1451 return rc;
1452 rc = call_int_hook(sb_alloc_security, sb);
1453 if (unlikely(rc))
1454 security_sb_free(sb);
1455 return rc;
1456 }
1457
1458 /**
1459 * security_sb_delete() - Release super_block LSM associated objects
1460 * @sb: filesystem superblock
1461 *
1462 * Release objects tied to a superblock (e.g. inodes). @sb contains the
1463 * super_block structure being released.
1464 */
security_sb_delete(struct super_block * sb)1465 void security_sb_delete(struct super_block *sb)
1466 {
1467 call_void_hook(sb_delete, sb);
1468 }
1469
1470 /**
1471 * security_sb_free() - Free a super_block LSM blob
1472 * @sb: filesystem superblock
1473 *
1474 * Deallocate and clear the sb->s_security field. @sb contains the super_block
1475 * structure to be modified.
1476 */
security_sb_free(struct super_block * sb)1477 void security_sb_free(struct super_block *sb)
1478 {
1479 call_void_hook(sb_free_security, sb);
1480 kfree(sb->s_security);
1481 sb->s_security = NULL;
1482 }
1483
1484 /**
1485 * security_free_mnt_opts() - Free memory associated with mount options
1486 * @mnt_opts: LSM processed mount options
1487 *
1488 * Free memory associated with @mnt_ops.
1489 */
security_free_mnt_opts(void ** mnt_opts)1490 void security_free_mnt_opts(void **mnt_opts)
1491 {
1492 if (!*mnt_opts)
1493 return;
1494 call_void_hook(sb_free_mnt_opts, *mnt_opts);
1495 *mnt_opts = NULL;
1496 }
1497 EXPORT_SYMBOL(security_free_mnt_opts);
1498
1499 /**
1500 * security_sb_eat_lsm_opts() - Consume LSM mount options
1501 * @options: mount options
1502 * @mnt_opts: LSM processed mount options
1503 *
1504 * Eat (scan @options) and save them in @mnt_opts.
1505 *
1506 * Return: Returns 0 on success, negative values on failure.
1507 */
security_sb_eat_lsm_opts(char * options,void ** mnt_opts)1508 int security_sb_eat_lsm_opts(char *options, void **mnt_opts)
1509 {
1510 return call_int_hook(sb_eat_lsm_opts, options, mnt_opts);
1511 }
1512 EXPORT_SYMBOL(security_sb_eat_lsm_opts);
1513
1514 /**
1515 * security_sb_mnt_opts_compat() - Check if new mount options are allowed
1516 * @sb: filesystem superblock
1517 * @mnt_opts: new mount options
1518 *
1519 * Determine if the new mount options in @mnt_opts are allowed given the
1520 * existing mounted filesystem at @sb. @sb superblock being compared.
1521 *
1522 * Return: Returns 0 if options are compatible.
1523 */
security_sb_mnt_opts_compat(struct super_block * sb,void * mnt_opts)1524 int security_sb_mnt_opts_compat(struct super_block *sb,
1525 void *mnt_opts)
1526 {
1527 return call_int_hook(sb_mnt_opts_compat, sb, mnt_opts);
1528 }
1529 EXPORT_SYMBOL(security_sb_mnt_opts_compat);
1530
1531 /**
1532 * security_sb_remount() - Verify no incompatible mount changes during remount
1533 * @sb: filesystem superblock
1534 * @mnt_opts: (re)mount options
1535 *
1536 * Extracts security system specific mount options and verifies no changes are
1537 * being made to those options.
1538 *
1539 * Return: Returns 0 if permission is granted.
1540 */
security_sb_remount(struct super_block * sb,void * mnt_opts)1541 int security_sb_remount(struct super_block *sb,
1542 void *mnt_opts)
1543 {
1544 return call_int_hook(sb_remount, sb, mnt_opts);
1545 }
1546 EXPORT_SYMBOL(security_sb_remount);
1547
1548 /**
1549 * security_sb_kern_mount() - Check if a kernel mount is allowed
1550 * @sb: filesystem superblock
1551 *
1552 * Mount this @sb if allowed by permissions.
1553 *
1554 * Return: Returns 0 if permission is granted.
1555 */
security_sb_kern_mount(const struct super_block * sb)1556 int security_sb_kern_mount(const struct super_block *sb)
1557 {
1558 return call_int_hook(sb_kern_mount, sb);
1559 }
1560
1561 /**
1562 * security_sb_show_options() - Output the mount options for a superblock
1563 * @m: output file
1564 * @sb: filesystem superblock
1565 *
1566 * Show (print on @m) mount options for this @sb.
1567 *
1568 * Return: Returns 0 on success, negative values on failure.
1569 */
security_sb_show_options(struct seq_file * m,struct super_block * sb)1570 int security_sb_show_options(struct seq_file *m, struct super_block *sb)
1571 {
1572 return call_int_hook(sb_show_options, m, sb);
1573 }
1574
1575 /**
1576 * security_sb_statfs() - Check if accessing fs stats is allowed
1577 * @dentry: superblock handle
1578 *
1579 * Check permission before obtaining filesystem statistics for the @mnt
1580 * mountpoint. @dentry is a handle on the superblock for the filesystem.
1581 *
1582 * Return: Returns 0 if permission is granted.
1583 */
security_sb_statfs(struct dentry * dentry)1584 int security_sb_statfs(struct dentry *dentry)
1585 {
1586 return call_int_hook(sb_statfs, dentry);
1587 }
1588
1589 /**
1590 * security_sb_mount() - Check permission for mounting a filesystem
1591 * @dev_name: filesystem backing device
1592 * @path: mount point
1593 * @type: filesystem type
1594 * @flags: mount flags
1595 * @data: filesystem specific data
1596 *
1597 * Check permission before an object specified by @dev_name is mounted on the
1598 * mount point named by @nd. For an ordinary mount, @dev_name identifies a
1599 * device if the file system type requires a device. For a remount
1600 * (@flags & MS_REMOUNT), @dev_name is irrelevant. For a loopback/bind mount
1601 * (@flags & MS_BIND), @dev_name identifies the pathname of the object being
1602 * mounted.
1603 *
1604 * Return: Returns 0 if permission is granted.
1605 */
security_sb_mount(const char * dev_name,const struct path * path,const char * type,unsigned long flags,void * data)1606 int security_sb_mount(const char *dev_name, const struct path *path,
1607 const char *type, unsigned long flags, void *data)
1608 {
1609 return call_int_hook(sb_mount, dev_name, path, type, flags, data);
1610 }
1611
1612 /**
1613 * security_sb_umount() - Check permission for unmounting a filesystem
1614 * @mnt: mounted filesystem
1615 * @flags: unmount flags
1616 *
1617 * Check permission before the @mnt file system is unmounted.
1618 *
1619 * Return: Returns 0 if permission is granted.
1620 */
security_sb_umount(struct vfsmount * mnt,int flags)1621 int security_sb_umount(struct vfsmount *mnt, int flags)
1622 {
1623 return call_int_hook(sb_umount, mnt, flags);
1624 }
1625
1626 /**
1627 * security_sb_pivotroot() - Check permissions for pivoting the rootfs
1628 * @old_path: new location for current rootfs
1629 * @new_path: location of the new rootfs
1630 *
1631 * Check permission before pivoting the root filesystem.
1632 *
1633 * Return: Returns 0 if permission is granted.
1634 */
security_sb_pivotroot(const struct path * old_path,const struct path * new_path)1635 int security_sb_pivotroot(const struct path *old_path,
1636 const struct path *new_path)
1637 {
1638 return call_int_hook(sb_pivotroot, old_path, new_path);
1639 }
1640
1641 /**
1642 * security_sb_set_mnt_opts() - Set the mount options for a filesystem
1643 * @sb: filesystem superblock
1644 * @mnt_opts: binary mount options
1645 * @kern_flags: kernel flags (in)
1646 * @set_kern_flags: kernel flags (out)
1647 *
1648 * Set the security relevant mount options used for a superblock.
1649 *
1650 * Return: Returns 0 on success, error on failure.
1651 */
security_sb_set_mnt_opts(struct super_block * sb,void * mnt_opts,unsigned long kern_flags,unsigned long * set_kern_flags)1652 int security_sb_set_mnt_opts(struct super_block *sb,
1653 void *mnt_opts,
1654 unsigned long kern_flags,
1655 unsigned long *set_kern_flags)
1656 {
1657 struct lsm_static_call *scall;
1658 int rc = mnt_opts ? -EOPNOTSUPP : LSM_RET_DEFAULT(sb_set_mnt_opts);
1659
1660 lsm_for_each_hook(scall, sb_set_mnt_opts) {
1661 rc = scall->hl->hook.sb_set_mnt_opts(sb, mnt_opts, kern_flags,
1662 set_kern_flags);
1663 if (rc != LSM_RET_DEFAULT(sb_set_mnt_opts))
1664 break;
1665 }
1666 return rc;
1667 }
1668 EXPORT_SYMBOL(security_sb_set_mnt_opts);
1669
1670 /**
1671 * security_sb_clone_mnt_opts() - Duplicate superblock mount options
1672 * @oldsb: source superblock
1673 * @newsb: destination superblock
1674 * @kern_flags: kernel flags (in)
1675 * @set_kern_flags: kernel flags (out)
1676 *
1677 * Copy all security options from a given superblock to another.
1678 *
1679 * Return: Returns 0 on success, error on failure.
1680 */
security_sb_clone_mnt_opts(const struct super_block * oldsb,struct super_block * newsb,unsigned long kern_flags,unsigned long * set_kern_flags)1681 int security_sb_clone_mnt_opts(const struct super_block *oldsb,
1682 struct super_block *newsb,
1683 unsigned long kern_flags,
1684 unsigned long *set_kern_flags)
1685 {
1686 return call_int_hook(sb_clone_mnt_opts, oldsb, newsb,
1687 kern_flags, set_kern_flags);
1688 }
1689 EXPORT_SYMBOL(security_sb_clone_mnt_opts);
1690
1691 /**
1692 * security_move_mount() - Check permissions for moving a mount
1693 * @from_path: source mount point
1694 * @to_path: destination mount point
1695 *
1696 * Check permission before a mount is moved.
1697 *
1698 * Return: Returns 0 if permission is granted.
1699 */
security_move_mount(const struct path * from_path,const struct path * to_path)1700 int security_move_mount(const struct path *from_path,
1701 const struct path *to_path)
1702 {
1703 return call_int_hook(move_mount, from_path, to_path);
1704 }
1705
1706 /**
1707 * security_path_notify() - Check if setting a watch is allowed
1708 * @path: file path
1709 * @mask: event mask
1710 * @obj_type: file path type
1711 *
1712 * Check permissions before setting a watch on events as defined by @mask, on
1713 * an object at @path, whose type is defined by @obj_type.
1714 *
1715 * Return: Returns 0 if permission is granted.
1716 */
security_path_notify(const struct path * path,u64 mask,unsigned int obj_type)1717 int security_path_notify(const struct path *path, u64 mask,
1718 unsigned int obj_type)
1719 {
1720 return call_int_hook(path_notify, path, mask, obj_type);
1721 }
1722
1723 /**
1724 * security_inode_alloc() - Allocate an inode LSM blob
1725 * @inode: the inode
1726 * @gfp: allocation flags
1727 *
1728 * Allocate and attach a security structure to @inode->i_security. The
1729 * i_security field is initialized to NULL when the inode structure is
1730 * allocated.
1731 *
1732 * Return: Return 0 if operation was successful.
1733 */
security_inode_alloc(struct inode * inode,gfp_t gfp)1734 int security_inode_alloc(struct inode *inode, gfp_t gfp)
1735 {
1736 int rc = lsm_inode_alloc(inode, gfp);
1737
1738 if (unlikely(rc))
1739 return rc;
1740 rc = call_int_hook(inode_alloc_security, inode);
1741 if (unlikely(rc))
1742 security_inode_free(inode);
1743 return rc;
1744 }
1745
inode_free_by_rcu(struct rcu_head * head)1746 static void inode_free_by_rcu(struct rcu_head *head)
1747 {
1748 /* The rcu head is at the start of the inode blob */
1749 call_void_hook(inode_free_security_rcu, head);
1750 kmem_cache_free(lsm_inode_cache, head);
1751 }
1752
1753 /**
1754 * security_inode_free() - Free an inode's LSM blob
1755 * @inode: the inode
1756 *
1757 * Release any LSM resources associated with @inode, although due to the
1758 * inode's RCU protections it is possible that the resources will not be
1759 * fully released until after the current RCU grace period has elapsed.
1760 *
1761 * It is important for LSMs to note that despite being present in a call to
1762 * security_inode_free(), @inode may still be referenced in a VFS path walk
1763 * and calls to security_inode_permission() may be made during, or after,
1764 * a call to security_inode_free(). For this reason the inode->i_security
1765 * field is released via a call_rcu() callback and any LSMs which need to
1766 * retain inode state for use in security_inode_permission() should only
1767 * release that state in the inode_free_security_rcu() LSM hook callback.
1768 */
security_inode_free(struct inode * inode)1769 void security_inode_free(struct inode *inode)
1770 {
1771 call_void_hook(inode_free_security, inode);
1772 if (!inode->i_security)
1773 return;
1774 call_rcu((struct rcu_head *)inode->i_security, inode_free_by_rcu);
1775 }
1776
1777 /**
1778 * security_dentry_init_security() - Perform dentry initialization
1779 * @dentry: the dentry to initialize
1780 * @mode: mode used to determine resource type
1781 * @name: name of the last path component
1782 * @xattr_name: name of the security/LSM xattr
1783 * @lsmctx: pointer to the resulting LSM context
1784 *
1785 * Compute a context for a dentry as the inode is not yet available since NFSv4
1786 * has no label backed by an EA anyway. It is important to note that
1787 * @xattr_name does not need to be free'd by the caller, it is a static string.
1788 *
1789 * Return: Returns 0 on success, negative values on failure.
1790 */
security_dentry_init_security(struct dentry * dentry,int mode,const struct qstr * name,const char ** xattr_name,struct lsm_context * lsmctx)1791 int security_dentry_init_security(struct dentry *dentry, int mode,
1792 const struct qstr *name,
1793 const char **xattr_name,
1794 struct lsm_context *lsmctx)
1795 {
1796 return call_int_hook(dentry_init_security, dentry, mode, name,
1797 xattr_name, lsmctx);
1798 }
1799 EXPORT_SYMBOL(security_dentry_init_security);
1800
1801 /**
1802 * security_dentry_create_files_as() - Perform dentry initialization
1803 * @dentry: the dentry to initialize
1804 * @mode: mode used to determine resource type
1805 * @name: name of the last path component
1806 * @old: creds to use for LSM context calculations
1807 * @new: creds to modify
1808 *
1809 * Compute a context for a dentry as the inode is not yet available and set
1810 * that context in passed in creds so that new files are created using that
1811 * context. Context is calculated using the passed in creds and not the creds
1812 * of the caller.
1813 *
1814 * Return: Returns 0 on success, error on failure.
1815 */
security_dentry_create_files_as(struct dentry * dentry,int mode,const struct qstr * name,const struct cred * old,struct cred * new)1816 int security_dentry_create_files_as(struct dentry *dentry, int mode,
1817 const struct qstr *name,
1818 const struct cred *old, struct cred *new)
1819 {
1820 return call_int_hook(dentry_create_files_as, dentry, mode,
1821 name, old, new);
1822 }
1823 EXPORT_SYMBOL(security_dentry_create_files_as);
1824
1825 /**
1826 * security_inode_init_security() - Initialize an inode's LSM context
1827 * @inode: the inode
1828 * @dir: parent directory
1829 * @qstr: last component of the pathname
1830 * @initxattrs: callback function to write xattrs
1831 * @fs_data: filesystem specific data
1832 *
1833 * Obtain the security attribute name suffix and value to set on a newly
1834 * created inode and set up the incore security field for the new inode. This
1835 * hook is called by the fs code as part of the inode creation transaction and
1836 * provides for atomic labeling of the inode, unlike the post_create/mkdir/...
1837 * hooks called by the VFS.
1838 *
1839 * The hook function is expected to populate the xattrs array, by calling
1840 * lsm_get_xattr_slot() to retrieve the slots reserved by the security module
1841 * with the lbs_xattr_count field of the lsm_blob_sizes structure. For each
1842 * slot, the hook function should set ->name to the attribute name suffix
1843 * (e.g. selinux), to allocate ->value (will be freed by the caller) and set it
1844 * to the attribute value, to set ->value_len to the length of the value. If
1845 * the security module does not use security attributes or does not wish to put
1846 * a security attribute on this particular inode, then it should return
1847 * -EOPNOTSUPP to skip this processing.
1848 *
1849 * Return: Returns 0 if the LSM successfully initialized all of the inode
1850 * security attributes that are required, negative values otherwise.
1851 */
security_inode_init_security(struct inode * inode,struct inode * dir,const struct qstr * qstr,const initxattrs initxattrs,void * fs_data)1852 int security_inode_init_security(struct inode *inode, struct inode *dir,
1853 const struct qstr *qstr,
1854 const initxattrs initxattrs, void *fs_data)
1855 {
1856 struct lsm_static_call *scall;
1857 struct xattr *new_xattrs = NULL;
1858 int ret = -EOPNOTSUPP, xattr_count = 0;
1859
1860 if (unlikely(IS_PRIVATE(inode)))
1861 return 0;
1862
1863 if (!blob_sizes.lbs_xattr_count)
1864 return 0;
1865
1866 if (initxattrs) {
1867 /* Allocate +1 as terminator. */
1868 new_xattrs = kcalloc(blob_sizes.lbs_xattr_count + 1,
1869 sizeof(*new_xattrs), GFP_NOFS);
1870 if (!new_xattrs)
1871 return -ENOMEM;
1872 }
1873
1874 lsm_for_each_hook(scall, inode_init_security) {
1875 ret = scall->hl->hook.inode_init_security(inode, dir, qstr, new_xattrs,
1876 &xattr_count);
1877 if (ret && ret != -EOPNOTSUPP)
1878 goto out;
1879 /*
1880 * As documented in lsm_hooks.h, -EOPNOTSUPP in this context
1881 * means that the LSM is not willing to provide an xattr, not
1882 * that it wants to signal an error. Thus, continue to invoke
1883 * the remaining LSMs.
1884 */
1885 }
1886
1887 /* If initxattrs() is NULL, xattr_count is zero, skip the call. */
1888 if (!xattr_count)
1889 goto out;
1890
1891 ret = initxattrs(inode, new_xattrs, fs_data);
1892 out:
1893 for (; xattr_count > 0; xattr_count--)
1894 kfree(new_xattrs[xattr_count - 1].value);
1895 kfree(new_xattrs);
1896 return (ret == -EOPNOTSUPP) ? 0 : ret;
1897 }
1898 EXPORT_SYMBOL(security_inode_init_security);
1899
1900 /**
1901 * security_inode_init_security_anon() - Initialize an anonymous inode
1902 * @inode: the inode
1903 * @name: the anonymous inode class
1904 * @context_inode: an optional related inode
1905 *
1906 * Set up the incore security field for the new anonymous inode and return
1907 * whether the inode creation is permitted by the security module or not.
1908 *
1909 * Return: Returns 0 on success, -EACCES if the security module denies the
1910 * creation of this inode, or another -errno upon other errors.
1911 */
security_inode_init_security_anon(struct inode * inode,const struct qstr * name,const struct inode * context_inode)1912 int security_inode_init_security_anon(struct inode *inode,
1913 const struct qstr *name,
1914 const struct inode *context_inode)
1915 {
1916 return call_int_hook(inode_init_security_anon, inode, name,
1917 context_inode);
1918 }
1919
1920 #ifdef CONFIG_SECURITY_PATH
1921 /**
1922 * security_path_mknod() - Check if creating a special file is allowed
1923 * @dir: parent directory
1924 * @dentry: new file
1925 * @mode: new file mode
1926 * @dev: device number
1927 *
1928 * Check permissions when creating a file. Note that this hook is called even
1929 * if mknod operation is being done for a regular file.
1930 *
1931 * Return: Returns 0 if permission is granted.
1932 */
security_path_mknod(const struct path * dir,struct dentry * dentry,umode_t mode,unsigned int dev)1933 int security_path_mknod(const struct path *dir, struct dentry *dentry,
1934 umode_t mode, unsigned int dev)
1935 {
1936 if (unlikely(IS_PRIVATE(d_backing_inode(dir->dentry))))
1937 return 0;
1938 return call_int_hook(path_mknod, dir, dentry, mode, dev);
1939 }
1940 EXPORT_SYMBOL(security_path_mknod);
1941
1942 /**
1943 * security_path_post_mknod() - Update inode security after reg file creation
1944 * @idmap: idmap of the mount
1945 * @dentry: new file
1946 *
1947 * Update inode security field after a regular file has been created.
1948 */
security_path_post_mknod(struct mnt_idmap * idmap,struct dentry * dentry)1949 void security_path_post_mknod(struct mnt_idmap *idmap, struct dentry *dentry)
1950 {
1951 if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
1952 return;
1953 call_void_hook(path_post_mknod, idmap, dentry);
1954 }
1955
1956 /**
1957 * security_path_mkdir() - Check if creating a new directory is allowed
1958 * @dir: parent directory
1959 * @dentry: new directory
1960 * @mode: new directory mode
1961 *
1962 * Check permissions to create a new directory in the existing directory.
1963 *
1964 * Return: Returns 0 if permission is granted.
1965 */
security_path_mkdir(const struct path * dir,struct dentry * dentry,umode_t mode)1966 int security_path_mkdir(const struct path *dir, struct dentry *dentry,
1967 umode_t mode)
1968 {
1969 if (unlikely(IS_PRIVATE(d_backing_inode(dir->dentry))))
1970 return 0;
1971 return call_int_hook(path_mkdir, dir, dentry, mode);
1972 }
1973 EXPORT_SYMBOL(security_path_mkdir);
1974
1975 /**
1976 * security_path_rmdir() - Check if removing a directory is allowed
1977 * @dir: parent directory
1978 * @dentry: directory to remove
1979 *
1980 * Check the permission to remove a directory.
1981 *
1982 * Return: Returns 0 if permission is granted.
1983 */
security_path_rmdir(const struct path * dir,struct dentry * dentry)1984 int security_path_rmdir(const struct path *dir, struct dentry *dentry)
1985 {
1986 if (unlikely(IS_PRIVATE(d_backing_inode(dir->dentry))))
1987 return 0;
1988 return call_int_hook(path_rmdir, dir, dentry);
1989 }
1990
1991 /**
1992 * security_path_unlink() - Check if removing a hard link is allowed
1993 * @dir: parent directory
1994 * @dentry: file
1995 *
1996 * Check the permission to remove a hard link to a file.
1997 *
1998 * Return: Returns 0 if permission is granted.
1999 */
security_path_unlink(const struct path * dir,struct dentry * dentry)2000 int security_path_unlink(const struct path *dir, struct dentry *dentry)
2001 {
2002 if (unlikely(IS_PRIVATE(d_backing_inode(dir->dentry))))
2003 return 0;
2004 return call_int_hook(path_unlink, dir, dentry);
2005 }
2006 EXPORT_SYMBOL(security_path_unlink);
2007
2008 /**
2009 * security_path_symlink() - Check if creating a symbolic link is allowed
2010 * @dir: parent directory
2011 * @dentry: symbolic link
2012 * @old_name: file pathname
2013 *
2014 * Check the permission to create a symbolic link to a file.
2015 *
2016 * Return: Returns 0 if permission is granted.
2017 */
security_path_symlink(const struct path * dir,struct dentry * dentry,const char * old_name)2018 int security_path_symlink(const struct path *dir, struct dentry *dentry,
2019 const char *old_name)
2020 {
2021 if (unlikely(IS_PRIVATE(d_backing_inode(dir->dentry))))
2022 return 0;
2023 return call_int_hook(path_symlink, dir, dentry, old_name);
2024 }
2025
2026 /**
2027 * security_path_link - Check if creating a hard link is allowed
2028 * @old_dentry: existing file
2029 * @new_dir: new parent directory
2030 * @new_dentry: new link
2031 *
2032 * Check permission before creating a new hard link to a file.
2033 *
2034 * Return: Returns 0 if permission is granted.
2035 */
security_path_link(struct dentry * old_dentry,const struct path * new_dir,struct dentry * new_dentry)2036 int security_path_link(struct dentry *old_dentry, const struct path *new_dir,
2037 struct dentry *new_dentry)
2038 {
2039 if (unlikely(IS_PRIVATE(d_backing_inode(old_dentry))))
2040 return 0;
2041 return call_int_hook(path_link, old_dentry, new_dir, new_dentry);
2042 }
2043
2044 /**
2045 * security_path_rename() - Check if renaming a file is allowed
2046 * @old_dir: parent directory of the old file
2047 * @old_dentry: the old file
2048 * @new_dir: parent directory of the new file
2049 * @new_dentry: the new file
2050 * @flags: flags
2051 *
2052 * Check for permission to rename a file or directory.
2053 *
2054 * Return: Returns 0 if permission is granted.
2055 */
security_path_rename(const struct path * old_dir,struct dentry * old_dentry,const struct path * new_dir,struct dentry * new_dentry,unsigned int flags)2056 int security_path_rename(const struct path *old_dir, struct dentry *old_dentry,
2057 const struct path *new_dir, struct dentry *new_dentry,
2058 unsigned int flags)
2059 {
2060 if (unlikely(IS_PRIVATE(d_backing_inode(old_dentry)) ||
2061 (d_is_positive(new_dentry) &&
2062 IS_PRIVATE(d_backing_inode(new_dentry)))))
2063 return 0;
2064
2065 return call_int_hook(path_rename, old_dir, old_dentry, new_dir,
2066 new_dentry, flags);
2067 }
2068 EXPORT_SYMBOL(security_path_rename);
2069
2070 /**
2071 * security_path_truncate() - Check if truncating a file is allowed
2072 * @path: file
2073 *
2074 * Check permission before truncating the file indicated by path. Note that
2075 * truncation permissions may also be checked based on already opened files,
2076 * using the security_file_truncate() hook.
2077 *
2078 * Return: Returns 0 if permission is granted.
2079 */
security_path_truncate(const struct path * path)2080 int security_path_truncate(const struct path *path)
2081 {
2082 if (unlikely(IS_PRIVATE(d_backing_inode(path->dentry))))
2083 return 0;
2084 return call_int_hook(path_truncate, path);
2085 }
2086
2087 /**
2088 * security_path_chmod() - Check if changing the file's mode is allowed
2089 * @path: file
2090 * @mode: new mode
2091 *
2092 * Check for permission to change a mode of the file @path. The new mode is
2093 * specified in @mode which is a bitmask of constants from
2094 * <include/uapi/linux/stat.h>.
2095 *
2096 * Return: Returns 0 if permission is granted.
2097 */
security_path_chmod(const struct path * path,umode_t mode)2098 int security_path_chmod(const struct path *path, umode_t mode)
2099 {
2100 if (unlikely(IS_PRIVATE(d_backing_inode(path->dentry))))
2101 return 0;
2102 return call_int_hook(path_chmod, path, mode);
2103 }
2104
2105 /**
2106 * security_path_chown() - Check if changing the file's owner/group is allowed
2107 * @path: file
2108 * @uid: file owner
2109 * @gid: file group
2110 *
2111 * Check for permission to change owner/group of a file or directory.
2112 *
2113 * Return: Returns 0 if permission is granted.
2114 */
security_path_chown(const struct path * path,kuid_t uid,kgid_t gid)2115 int security_path_chown(const struct path *path, kuid_t uid, kgid_t gid)
2116 {
2117 if (unlikely(IS_PRIVATE(d_backing_inode(path->dentry))))
2118 return 0;
2119 return call_int_hook(path_chown, path, uid, gid);
2120 }
2121
2122 /**
2123 * security_path_chroot() - Check if changing the root directory is allowed
2124 * @path: directory
2125 *
2126 * Check for permission to change root directory.
2127 *
2128 * Return: Returns 0 if permission is granted.
2129 */
security_path_chroot(const struct path * path)2130 int security_path_chroot(const struct path *path)
2131 {
2132 return call_int_hook(path_chroot, path);
2133 }
2134 #endif /* CONFIG_SECURITY_PATH */
2135
2136 /**
2137 * security_inode_create() - Check if creating a file is allowed
2138 * @dir: the parent directory
2139 * @dentry: the file being created
2140 * @mode: requested file mode
2141 *
2142 * Check permission to create a regular file.
2143 *
2144 * Return: Returns 0 if permission is granted.
2145 */
security_inode_create(struct inode * dir,struct dentry * dentry,umode_t mode)2146 int security_inode_create(struct inode *dir, struct dentry *dentry,
2147 umode_t mode)
2148 {
2149 if (unlikely(IS_PRIVATE(dir)))
2150 return 0;
2151 return call_int_hook(inode_create, dir, dentry, mode);
2152 }
2153 EXPORT_SYMBOL_GPL(security_inode_create);
2154
2155 /**
2156 * security_inode_post_create_tmpfile() - Update inode security of new tmpfile
2157 * @idmap: idmap of the mount
2158 * @inode: inode of the new tmpfile
2159 *
2160 * Update inode security data after a tmpfile has been created.
2161 */
security_inode_post_create_tmpfile(struct mnt_idmap * idmap,struct inode * inode)2162 void security_inode_post_create_tmpfile(struct mnt_idmap *idmap,
2163 struct inode *inode)
2164 {
2165 if (unlikely(IS_PRIVATE(inode)))
2166 return;
2167 call_void_hook(inode_post_create_tmpfile, idmap, inode);
2168 }
2169
2170 /**
2171 * security_inode_link() - Check if creating a hard link is allowed
2172 * @old_dentry: existing file
2173 * @dir: new parent directory
2174 * @new_dentry: new link
2175 *
2176 * Check permission before creating a new hard link to a file.
2177 *
2178 * Return: Returns 0 if permission is granted.
2179 */
security_inode_link(struct dentry * old_dentry,struct inode * dir,struct dentry * new_dentry)2180 int security_inode_link(struct dentry *old_dentry, struct inode *dir,
2181 struct dentry *new_dentry)
2182 {
2183 if (unlikely(IS_PRIVATE(d_backing_inode(old_dentry))))
2184 return 0;
2185 return call_int_hook(inode_link, old_dentry, dir, new_dentry);
2186 }
2187
2188 /**
2189 * security_inode_unlink() - Check if removing a hard link is allowed
2190 * @dir: parent directory
2191 * @dentry: file
2192 *
2193 * Check the permission to remove a hard link to a file.
2194 *
2195 * Return: Returns 0 if permission is granted.
2196 */
security_inode_unlink(struct inode * dir,struct dentry * dentry)2197 int security_inode_unlink(struct inode *dir, struct dentry *dentry)
2198 {
2199 if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
2200 return 0;
2201 return call_int_hook(inode_unlink, dir, dentry);
2202 }
2203
2204 /**
2205 * security_inode_symlink() - Check if creating a symbolic link is allowed
2206 * @dir: parent directory
2207 * @dentry: symbolic link
2208 * @old_name: existing filename
2209 *
2210 * Check the permission to create a symbolic link to a file.
2211 *
2212 * Return: Returns 0 if permission is granted.
2213 */
security_inode_symlink(struct inode * dir,struct dentry * dentry,const char * old_name)2214 int security_inode_symlink(struct inode *dir, struct dentry *dentry,
2215 const char *old_name)
2216 {
2217 if (unlikely(IS_PRIVATE(dir)))
2218 return 0;
2219 return call_int_hook(inode_symlink, dir, dentry, old_name);
2220 }
2221
2222 /**
2223 * security_inode_mkdir() - Check if creating a new directory is allowed
2224 * @dir: parent directory
2225 * @dentry: new directory
2226 * @mode: new directory mode
2227 *
2228 * Check permissions to create a new directory in the existing directory
2229 * associated with inode structure @dir.
2230 *
2231 * Return: Returns 0 if permission is granted.
2232 */
security_inode_mkdir(struct inode * dir,struct dentry * dentry,umode_t mode)2233 int security_inode_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
2234 {
2235 if (unlikely(IS_PRIVATE(dir)))
2236 return 0;
2237 return call_int_hook(inode_mkdir, dir, dentry, mode);
2238 }
2239 EXPORT_SYMBOL_GPL(security_inode_mkdir);
2240
2241 /**
2242 * security_inode_rmdir() - Check if removing a directory is allowed
2243 * @dir: parent directory
2244 * @dentry: directory to be removed
2245 *
2246 * Check the permission to remove a directory.
2247 *
2248 * Return: Returns 0 if permission is granted.
2249 */
security_inode_rmdir(struct inode * dir,struct dentry * dentry)2250 int security_inode_rmdir(struct inode *dir, struct dentry *dentry)
2251 {
2252 if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
2253 return 0;
2254 return call_int_hook(inode_rmdir, dir, dentry);
2255 }
2256
2257 /**
2258 * security_inode_mknod() - Check if creating a special file is allowed
2259 * @dir: parent directory
2260 * @dentry: new file
2261 * @mode: new file mode
2262 * @dev: device number
2263 *
2264 * Check permissions when creating a special file (or a socket or a fifo file
2265 * created via the mknod system call). Note that if mknod operation is being
2266 * done for a regular file, then the create hook will be called and not this
2267 * hook.
2268 *
2269 * Return: Returns 0 if permission is granted.
2270 */
security_inode_mknod(struct inode * dir,struct dentry * dentry,umode_t mode,dev_t dev)2271 int security_inode_mknod(struct inode *dir, struct dentry *dentry,
2272 umode_t mode, dev_t dev)
2273 {
2274 if (unlikely(IS_PRIVATE(dir)))
2275 return 0;
2276 return call_int_hook(inode_mknod, dir, dentry, mode, dev);
2277 }
2278
2279 /**
2280 * security_inode_rename() - Check if renaming a file is allowed
2281 * @old_dir: parent directory of the old file
2282 * @old_dentry: the old file
2283 * @new_dir: parent directory of the new file
2284 * @new_dentry: the new file
2285 * @flags: flags
2286 *
2287 * Check for permission to rename a file or directory.
2288 *
2289 * Return: Returns 0 if permission is granted.
2290 */
security_inode_rename(struct inode * old_dir,struct dentry * old_dentry,struct inode * new_dir,struct dentry * new_dentry,unsigned int flags)2291 int security_inode_rename(struct inode *old_dir, struct dentry *old_dentry,
2292 struct inode *new_dir, struct dentry *new_dentry,
2293 unsigned int flags)
2294 {
2295 if (unlikely(IS_PRIVATE(d_backing_inode(old_dentry)) ||
2296 (d_is_positive(new_dentry) &&
2297 IS_PRIVATE(d_backing_inode(new_dentry)))))
2298 return 0;
2299
2300 if (flags & RENAME_EXCHANGE) {
2301 int err = call_int_hook(inode_rename, new_dir, new_dentry,
2302 old_dir, old_dentry);
2303 if (err)
2304 return err;
2305 }
2306
2307 return call_int_hook(inode_rename, old_dir, old_dentry,
2308 new_dir, new_dentry);
2309 }
2310
2311 /**
2312 * security_inode_readlink() - Check if reading a symbolic link is allowed
2313 * @dentry: link
2314 *
2315 * Check the permission to read the symbolic link.
2316 *
2317 * Return: Returns 0 if permission is granted.
2318 */
security_inode_readlink(struct dentry * dentry)2319 int security_inode_readlink(struct dentry *dentry)
2320 {
2321 if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
2322 return 0;
2323 return call_int_hook(inode_readlink, dentry);
2324 }
2325
2326 /**
2327 * security_inode_follow_link() - Check if following a symbolic link is allowed
2328 * @dentry: link dentry
2329 * @inode: link inode
2330 * @rcu: true if in RCU-walk mode
2331 *
2332 * Check permission to follow a symbolic link when looking up a pathname. If
2333 * @rcu is true, @inode is not stable.
2334 *
2335 * Return: Returns 0 if permission is granted.
2336 */
security_inode_follow_link(struct dentry * dentry,struct inode * inode,bool rcu)2337 int security_inode_follow_link(struct dentry *dentry, struct inode *inode,
2338 bool rcu)
2339 {
2340 if (unlikely(IS_PRIVATE(inode)))
2341 return 0;
2342 return call_int_hook(inode_follow_link, dentry, inode, rcu);
2343 }
2344
2345 /**
2346 * security_inode_permission() - Check if accessing an inode is allowed
2347 * @inode: inode
2348 * @mask: access mask
2349 *
2350 * Check permission before accessing an inode. This hook is called by the
2351 * existing Linux permission function, so a security module can use it to
2352 * provide additional checking for existing Linux permission checks. Notice
2353 * that this hook is called when a file is opened (as well as many other
2354 * operations), whereas the file_security_ops permission hook is called when
2355 * the actual read/write operations are performed.
2356 *
2357 * Return: Returns 0 if permission is granted.
2358 */
security_inode_permission(struct inode * inode,int mask)2359 int security_inode_permission(struct inode *inode, int mask)
2360 {
2361 if (unlikely(IS_PRIVATE(inode)))
2362 return 0;
2363 return call_int_hook(inode_permission, inode, mask);
2364 }
2365
2366 /**
2367 * security_inode_setattr() - Check if setting file attributes is allowed
2368 * @idmap: idmap of the mount
2369 * @dentry: file
2370 * @attr: new attributes
2371 *
2372 * Check permission before setting file attributes. Note that the kernel call
2373 * to notify_change is performed from several locations, whenever file
2374 * attributes change (such as when a file is truncated, chown/chmod operations,
2375 * transferring disk quotas, etc).
2376 *
2377 * Return: Returns 0 if permission is granted.
2378 */
security_inode_setattr(struct mnt_idmap * idmap,struct dentry * dentry,struct iattr * attr)2379 int security_inode_setattr(struct mnt_idmap *idmap,
2380 struct dentry *dentry, struct iattr *attr)
2381 {
2382 if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
2383 return 0;
2384 return call_int_hook(inode_setattr, idmap, dentry, attr);
2385 }
2386 EXPORT_SYMBOL_GPL(security_inode_setattr);
2387
2388 /**
2389 * security_inode_post_setattr() - Update the inode after a setattr operation
2390 * @idmap: idmap of the mount
2391 * @dentry: file
2392 * @ia_valid: file attributes set
2393 *
2394 * Update inode security field after successful setting file attributes.
2395 */
security_inode_post_setattr(struct mnt_idmap * idmap,struct dentry * dentry,int ia_valid)2396 void security_inode_post_setattr(struct mnt_idmap *idmap, struct dentry *dentry,
2397 int ia_valid)
2398 {
2399 if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
2400 return;
2401 call_void_hook(inode_post_setattr, idmap, dentry, ia_valid);
2402 }
2403
2404 /**
2405 * security_inode_getattr() - Check if getting file attributes is allowed
2406 * @path: file
2407 *
2408 * Check permission before obtaining file attributes.
2409 *
2410 * Return: Returns 0 if permission is granted.
2411 */
security_inode_getattr(const struct path * path)2412 int security_inode_getattr(const struct path *path)
2413 {
2414 if (unlikely(IS_PRIVATE(d_backing_inode(path->dentry))))
2415 return 0;
2416 return call_int_hook(inode_getattr, path);
2417 }
2418
2419 /**
2420 * security_inode_setxattr() - Check if setting file xattrs is allowed
2421 * @idmap: idmap of the mount
2422 * @dentry: file
2423 * @name: xattr name
2424 * @value: xattr value
2425 * @size: size of xattr value
2426 * @flags: flags
2427 *
2428 * This hook performs the desired permission checks before setting the extended
2429 * attributes (xattrs) on @dentry. It is important to note that we have some
2430 * additional logic before the main LSM implementation calls to detect if we
2431 * need to perform an additional capability check at the LSM layer.
2432 *
2433 * Normally we enforce a capability check prior to executing the various LSM
2434 * hook implementations, but if a LSM wants to avoid this capability check,
2435 * it can register a 'inode_xattr_skipcap' hook and return a value of 1 for
2436 * xattrs that it wants to avoid the capability check, leaving the LSM fully
2437 * responsible for enforcing the access control for the specific xattr. If all
2438 * of the enabled LSMs refrain from registering a 'inode_xattr_skipcap' hook,
2439 * or return a 0 (the default return value), the capability check is still
2440 * performed. If no 'inode_xattr_skipcap' hooks are registered the capability
2441 * check is performed.
2442 *
2443 * Return: Returns 0 if permission is granted.
2444 */
security_inode_setxattr(struct mnt_idmap * idmap,struct dentry * dentry,const char * name,const void * value,size_t size,int flags)2445 int security_inode_setxattr(struct mnt_idmap *idmap,
2446 struct dentry *dentry, const char *name,
2447 const void *value, size_t size, int flags)
2448 {
2449 int rc;
2450
2451 if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
2452 return 0;
2453
2454 /* enforce the capability checks at the lsm layer, if needed */
2455 if (!call_int_hook(inode_xattr_skipcap, name)) {
2456 rc = cap_inode_setxattr(dentry, name, value, size, flags);
2457 if (rc)
2458 return rc;
2459 }
2460
2461 return call_int_hook(inode_setxattr, idmap, dentry, name, value, size,
2462 flags);
2463 }
2464
2465 /**
2466 * security_inode_set_acl() - Check if setting posix acls is allowed
2467 * @idmap: idmap of the mount
2468 * @dentry: file
2469 * @acl_name: acl name
2470 * @kacl: acl struct
2471 *
2472 * Check permission before setting posix acls, the posix acls in @kacl are
2473 * identified by @acl_name.
2474 *
2475 * Return: Returns 0 if permission is granted.
2476 */
security_inode_set_acl(struct mnt_idmap * idmap,struct dentry * dentry,const char * acl_name,struct posix_acl * kacl)2477 int security_inode_set_acl(struct mnt_idmap *idmap,
2478 struct dentry *dentry, const char *acl_name,
2479 struct posix_acl *kacl)
2480 {
2481 if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
2482 return 0;
2483 return call_int_hook(inode_set_acl, idmap, dentry, acl_name, kacl);
2484 }
2485
2486 /**
2487 * security_inode_post_set_acl() - Update inode security from posix acls set
2488 * @dentry: file
2489 * @acl_name: acl name
2490 * @kacl: acl struct
2491 *
2492 * Update inode security data after successfully setting posix acls on @dentry.
2493 * The posix acls in @kacl are identified by @acl_name.
2494 */
security_inode_post_set_acl(struct dentry * dentry,const char * acl_name,struct posix_acl * kacl)2495 void security_inode_post_set_acl(struct dentry *dentry, const char *acl_name,
2496 struct posix_acl *kacl)
2497 {
2498 if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
2499 return;
2500 call_void_hook(inode_post_set_acl, dentry, acl_name, kacl);
2501 }
2502
2503 /**
2504 * security_inode_get_acl() - Check if reading posix acls is allowed
2505 * @idmap: idmap of the mount
2506 * @dentry: file
2507 * @acl_name: acl name
2508 *
2509 * Check permission before getting osix acls, the posix acls are identified by
2510 * @acl_name.
2511 *
2512 * Return: Returns 0 if permission is granted.
2513 */
security_inode_get_acl(struct mnt_idmap * idmap,struct dentry * dentry,const char * acl_name)2514 int security_inode_get_acl(struct mnt_idmap *idmap,
2515 struct dentry *dentry, const char *acl_name)
2516 {
2517 if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
2518 return 0;
2519 return call_int_hook(inode_get_acl, idmap, dentry, acl_name);
2520 }
2521
2522 /**
2523 * security_inode_remove_acl() - Check if removing a posix acl is allowed
2524 * @idmap: idmap of the mount
2525 * @dentry: file
2526 * @acl_name: acl name
2527 *
2528 * Check permission before removing posix acls, the posix acls are identified
2529 * by @acl_name.
2530 *
2531 * Return: Returns 0 if permission is granted.
2532 */
security_inode_remove_acl(struct mnt_idmap * idmap,struct dentry * dentry,const char * acl_name)2533 int security_inode_remove_acl(struct mnt_idmap *idmap,
2534 struct dentry *dentry, const char *acl_name)
2535 {
2536 if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
2537 return 0;
2538 return call_int_hook(inode_remove_acl, idmap, dentry, acl_name);
2539 }
2540
2541 /**
2542 * security_inode_post_remove_acl() - Update inode security after rm posix acls
2543 * @idmap: idmap of the mount
2544 * @dentry: file
2545 * @acl_name: acl name
2546 *
2547 * Update inode security data after successfully removing posix acls on
2548 * @dentry in @idmap. The posix acls are identified by @acl_name.
2549 */
security_inode_post_remove_acl(struct mnt_idmap * idmap,struct dentry * dentry,const char * acl_name)2550 void security_inode_post_remove_acl(struct mnt_idmap *idmap,
2551 struct dentry *dentry, const char *acl_name)
2552 {
2553 if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
2554 return;
2555 call_void_hook(inode_post_remove_acl, idmap, dentry, acl_name);
2556 }
2557
2558 /**
2559 * security_inode_post_setxattr() - Update the inode after a setxattr operation
2560 * @dentry: file
2561 * @name: xattr name
2562 * @value: xattr value
2563 * @size: xattr value size
2564 * @flags: flags
2565 *
2566 * Update inode security field after successful setxattr operation.
2567 */
security_inode_post_setxattr(struct dentry * dentry,const char * name,const void * value,size_t size,int flags)2568 void security_inode_post_setxattr(struct dentry *dentry, const char *name,
2569 const void *value, size_t size, int flags)
2570 {
2571 if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
2572 return;
2573 call_void_hook(inode_post_setxattr, dentry, name, value, size, flags);
2574 }
2575
2576 /**
2577 * security_inode_getxattr() - Check if xattr access is allowed
2578 * @dentry: file
2579 * @name: xattr name
2580 *
2581 * Check permission before obtaining the extended attributes identified by
2582 * @name for @dentry.
2583 *
2584 * Return: Returns 0 if permission is granted.
2585 */
security_inode_getxattr(struct dentry * dentry,const char * name)2586 int security_inode_getxattr(struct dentry *dentry, const char *name)
2587 {
2588 if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
2589 return 0;
2590 return call_int_hook(inode_getxattr, dentry, name);
2591 }
2592
2593 /**
2594 * security_inode_listxattr() - Check if listing xattrs is allowed
2595 * @dentry: file
2596 *
2597 * Check permission before obtaining the list of extended attribute names for
2598 * @dentry.
2599 *
2600 * Return: Returns 0 if permission is granted.
2601 */
security_inode_listxattr(struct dentry * dentry)2602 int security_inode_listxattr(struct dentry *dentry)
2603 {
2604 if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
2605 return 0;
2606 return call_int_hook(inode_listxattr, dentry);
2607 }
2608
2609 /**
2610 * security_inode_removexattr() - Check if removing an xattr is allowed
2611 * @idmap: idmap of the mount
2612 * @dentry: file
2613 * @name: xattr name
2614 *
2615 * This hook performs the desired permission checks before setting the extended
2616 * attributes (xattrs) on @dentry. It is important to note that we have some
2617 * additional logic before the main LSM implementation calls to detect if we
2618 * need to perform an additional capability check at the LSM layer.
2619 *
2620 * Normally we enforce a capability check prior to executing the various LSM
2621 * hook implementations, but if a LSM wants to avoid this capability check,
2622 * it can register a 'inode_xattr_skipcap' hook and return a value of 1 for
2623 * xattrs that it wants to avoid the capability check, leaving the LSM fully
2624 * responsible for enforcing the access control for the specific xattr. If all
2625 * of the enabled LSMs refrain from registering a 'inode_xattr_skipcap' hook,
2626 * or return a 0 (the default return value), the capability check is still
2627 * performed. If no 'inode_xattr_skipcap' hooks are registered the capability
2628 * check is performed.
2629 *
2630 * Return: Returns 0 if permission is granted.
2631 */
security_inode_removexattr(struct mnt_idmap * idmap,struct dentry * dentry,const char * name)2632 int security_inode_removexattr(struct mnt_idmap *idmap,
2633 struct dentry *dentry, const char *name)
2634 {
2635 int rc;
2636
2637 if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
2638 return 0;
2639
2640 /* enforce the capability checks at the lsm layer, if needed */
2641 if (!call_int_hook(inode_xattr_skipcap, name)) {
2642 rc = cap_inode_removexattr(idmap, dentry, name);
2643 if (rc)
2644 return rc;
2645 }
2646
2647 return call_int_hook(inode_removexattr, idmap, dentry, name);
2648 }
2649
2650 /**
2651 * security_inode_post_removexattr() - Update the inode after a removexattr op
2652 * @dentry: file
2653 * @name: xattr name
2654 *
2655 * Update the inode after a successful removexattr operation.
2656 */
security_inode_post_removexattr(struct dentry * dentry,const char * name)2657 void security_inode_post_removexattr(struct dentry *dentry, const char *name)
2658 {
2659 if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
2660 return;
2661 call_void_hook(inode_post_removexattr, dentry, name);
2662 }
2663
2664 /**
2665 * security_inode_file_setattr() - check if setting fsxattr is allowed
2666 * @dentry: file to set filesystem extended attributes on
2667 * @fa: extended attributes to set on the inode
2668 *
2669 * Called when file_setattr() syscall or FS_IOC_FSSETXATTR ioctl() is called on
2670 * inode
2671 *
2672 * Return: Returns 0 if permission is granted.
2673 */
security_inode_file_setattr(struct dentry * dentry,struct file_kattr * fa)2674 int security_inode_file_setattr(struct dentry *dentry, struct file_kattr *fa)
2675 {
2676 return call_int_hook(inode_file_setattr, dentry, fa);
2677 }
2678
2679 /**
2680 * security_inode_file_getattr() - check if retrieving fsxattr is allowed
2681 * @dentry: file to retrieve filesystem extended attributes from
2682 * @fa: extended attributes to get
2683 *
2684 * Called when file_getattr() syscall or FS_IOC_FSGETXATTR ioctl() is called on
2685 * inode
2686 *
2687 * Return: Returns 0 if permission is granted.
2688 */
security_inode_file_getattr(struct dentry * dentry,struct file_kattr * fa)2689 int security_inode_file_getattr(struct dentry *dentry, struct file_kattr *fa)
2690 {
2691 return call_int_hook(inode_file_getattr, dentry, fa);
2692 }
2693
2694 /**
2695 * security_inode_need_killpriv() - Check if security_inode_killpriv() required
2696 * @dentry: associated dentry
2697 *
2698 * Called when an inode has been changed to determine if
2699 * security_inode_killpriv() should be called.
2700 *
2701 * Return: Return <0 on error to abort the inode change operation, return 0 if
2702 * security_inode_killpriv() does not need to be called, return >0 if
2703 * security_inode_killpriv() does need to be called.
2704 */
security_inode_need_killpriv(struct dentry * dentry)2705 int security_inode_need_killpriv(struct dentry *dentry)
2706 {
2707 return call_int_hook(inode_need_killpriv, dentry);
2708 }
2709
2710 /**
2711 * security_inode_killpriv() - The setuid bit is removed, update LSM state
2712 * @idmap: idmap of the mount
2713 * @dentry: associated dentry
2714 *
2715 * The @dentry's setuid bit is being removed. Remove similar security labels.
2716 * Called with the dentry->d_inode->i_mutex held.
2717 *
2718 * Return: Return 0 on success. If error is returned, then the operation
2719 * causing setuid bit removal is failed.
2720 */
security_inode_killpriv(struct mnt_idmap * idmap,struct dentry * dentry)2721 int security_inode_killpriv(struct mnt_idmap *idmap,
2722 struct dentry *dentry)
2723 {
2724 return call_int_hook(inode_killpriv, idmap, dentry);
2725 }
2726
2727 /**
2728 * security_inode_getsecurity() - Get the xattr security label of an inode
2729 * @idmap: idmap of the mount
2730 * @inode: inode
2731 * @name: xattr name
2732 * @buffer: security label buffer
2733 * @alloc: allocation flag
2734 *
2735 * Retrieve a copy of the extended attribute representation of the security
2736 * label associated with @name for @inode via @buffer. Note that @name is the
2737 * remainder of the attribute name after the security prefix has been removed.
2738 * @alloc is used to specify if the call should return a value via the buffer
2739 * or just the value length.
2740 *
2741 * Return: Returns size of buffer on success.
2742 */
security_inode_getsecurity(struct mnt_idmap * idmap,struct inode * inode,const char * name,void ** buffer,bool alloc)2743 int security_inode_getsecurity(struct mnt_idmap *idmap,
2744 struct inode *inode, const char *name,
2745 void **buffer, bool alloc)
2746 {
2747 if (unlikely(IS_PRIVATE(inode)))
2748 return LSM_RET_DEFAULT(inode_getsecurity);
2749
2750 return call_int_hook(inode_getsecurity, idmap, inode, name, buffer,
2751 alloc);
2752 }
2753
2754 /**
2755 * security_inode_setsecurity() - Set the xattr security label of an inode
2756 * @inode: inode
2757 * @name: xattr name
2758 * @value: security label
2759 * @size: length of security label
2760 * @flags: flags
2761 *
2762 * Set the security label associated with @name for @inode from the extended
2763 * attribute value @value. @size indicates the size of the @value in bytes.
2764 * @flags may be XATTR_CREATE, XATTR_REPLACE, or 0. Note that @name is the
2765 * remainder of the attribute name after the security. prefix has been removed.
2766 *
2767 * Return: Returns 0 on success.
2768 */
security_inode_setsecurity(struct inode * inode,const char * name,const void * value,size_t size,int flags)2769 int security_inode_setsecurity(struct inode *inode, const char *name,
2770 const void *value, size_t size, int flags)
2771 {
2772 if (unlikely(IS_PRIVATE(inode)))
2773 return LSM_RET_DEFAULT(inode_setsecurity);
2774
2775 return call_int_hook(inode_setsecurity, inode, name, value, size,
2776 flags);
2777 }
2778
2779 /**
2780 * security_inode_listsecurity() - List the xattr security label names
2781 * @inode: inode
2782 * @buffer: buffer
2783 * @buffer_size: size of buffer
2784 *
2785 * Copy the extended attribute names for the security labels associated with
2786 * @inode into @buffer. The maximum size of @buffer is specified by
2787 * @buffer_size. @buffer may be NULL to request the size of the buffer
2788 * required.
2789 *
2790 * Return: Returns number of bytes used/required on success.
2791 */
security_inode_listsecurity(struct inode * inode,char * buffer,size_t buffer_size)2792 int security_inode_listsecurity(struct inode *inode,
2793 char *buffer, size_t buffer_size)
2794 {
2795 if (unlikely(IS_PRIVATE(inode)))
2796 return 0;
2797 return call_int_hook(inode_listsecurity, inode, buffer, buffer_size);
2798 }
2799 EXPORT_SYMBOL(security_inode_listsecurity);
2800
2801 /**
2802 * security_inode_getlsmprop() - Get an inode's LSM data
2803 * @inode: inode
2804 * @prop: lsm specific information to return
2805 *
2806 * Get the lsm specific information associated with the node.
2807 */
security_inode_getlsmprop(struct inode * inode,struct lsm_prop * prop)2808 void security_inode_getlsmprop(struct inode *inode, struct lsm_prop *prop)
2809 {
2810 call_void_hook(inode_getlsmprop, inode, prop);
2811 }
2812
2813 /**
2814 * security_inode_copy_up() - Create new creds for an overlayfs copy-up op
2815 * @src: union dentry of copy-up file
2816 * @new: newly created creds
2817 *
2818 * A file is about to be copied up from lower layer to upper layer of overlay
2819 * filesystem. Security module can prepare a set of new creds and modify as
2820 * need be and return new creds. Caller will switch to new creds temporarily to
2821 * create new file and release newly allocated creds.
2822 *
2823 * Return: Returns 0 on success or a negative error code on error.
2824 */
security_inode_copy_up(struct dentry * src,struct cred ** new)2825 int security_inode_copy_up(struct dentry *src, struct cred **new)
2826 {
2827 return call_int_hook(inode_copy_up, src, new);
2828 }
2829 EXPORT_SYMBOL(security_inode_copy_up);
2830
2831 /**
2832 * security_inode_copy_up_xattr() - Filter xattrs in an overlayfs copy-up op
2833 * @src: union dentry of copy-up file
2834 * @name: xattr name
2835 *
2836 * Filter the xattrs being copied up when a unioned file is copied up from a
2837 * lower layer to the union/overlay layer. The caller is responsible for
2838 * reading and writing the xattrs, this hook is merely a filter.
2839 *
2840 * Return: Returns 0 to accept the xattr, -ECANCELED to discard the xattr,
2841 * -EOPNOTSUPP if the security module does not know about attribute,
2842 * or a negative error code to abort the copy up.
2843 */
security_inode_copy_up_xattr(struct dentry * src,const char * name)2844 int security_inode_copy_up_xattr(struct dentry *src, const char *name)
2845 {
2846 int rc;
2847
2848 rc = call_int_hook(inode_copy_up_xattr, src, name);
2849 if (rc != LSM_RET_DEFAULT(inode_copy_up_xattr))
2850 return rc;
2851
2852 return LSM_RET_DEFAULT(inode_copy_up_xattr);
2853 }
2854 EXPORT_SYMBOL(security_inode_copy_up_xattr);
2855
2856 /**
2857 * security_inode_setintegrity() - Set the inode's integrity data
2858 * @inode: inode
2859 * @type: type of integrity, e.g. hash digest, signature, etc
2860 * @value: the integrity value
2861 * @size: size of the integrity value
2862 *
2863 * Register a verified integrity measurement of a inode with LSMs.
2864 * LSMs should free the previously saved data if @value is NULL.
2865 *
2866 * Return: Returns 0 on success, negative values on failure.
2867 */
security_inode_setintegrity(const struct inode * inode,enum lsm_integrity_type type,const void * value,size_t size)2868 int security_inode_setintegrity(const struct inode *inode,
2869 enum lsm_integrity_type type, const void *value,
2870 size_t size)
2871 {
2872 return call_int_hook(inode_setintegrity, inode, type, value, size);
2873 }
2874 EXPORT_SYMBOL(security_inode_setintegrity);
2875
2876 /**
2877 * security_kernfs_init_security() - Init LSM context for a kernfs node
2878 * @kn_dir: parent kernfs node
2879 * @kn: the kernfs node to initialize
2880 *
2881 * Initialize the security context of a newly created kernfs node based on its
2882 * own and its parent's attributes.
2883 *
2884 * Return: Returns 0 if permission is granted.
2885 */
security_kernfs_init_security(struct kernfs_node * kn_dir,struct kernfs_node * kn)2886 int security_kernfs_init_security(struct kernfs_node *kn_dir,
2887 struct kernfs_node *kn)
2888 {
2889 return call_int_hook(kernfs_init_security, kn_dir, kn);
2890 }
2891
2892 /**
2893 * security_file_permission() - Check file permissions
2894 * @file: file
2895 * @mask: requested permissions
2896 *
2897 * Check file permissions before accessing an open file. This hook is called
2898 * by various operations that read or write files. A security module can use
2899 * this hook to perform additional checking on these operations, e.g. to
2900 * revalidate permissions on use to support privilege bracketing or policy
2901 * changes. Notice that this hook is used when the actual read/write
2902 * operations are performed, whereas the inode_security_ops hook is called when
2903 * a file is opened (as well as many other operations). Although this hook can
2904 * be used to revalidate permissions for various system call operations that
2905 * read or write files, it does not address the revalidation of permissions for
2906 * memory-mapped files. Security modules must handle this separately if they
2907 * need such revalidation.
2908 *
2909 * Return: Returns 0 if permission is granted.
2910 */
security_file_permission(struct file * file,int mask)2911 int security_file_permission(struct file *file, int mask)
2912 {
2913 return call_int_hook(file_permission, file, mask);
2914 }
2915
2916 /**
2917 * security_file_alloc() - Allocate and init a file's LSM blob
2918 * @file: the file
2919 *
2920 * Allocate and attach a security structure to the file->f_security field. The
2921 * security field is initialized to NULL when the structure is first created.
2922 *
2923 * Return: Return 0 if the hook is successful and permission is granted.
2924 */
security_file_alloc(struct file * file)2925 int security_file_alloc(struct file *file)
2926 {
2927 int rc = lsm_file_alloc(file);
2928
2929 if (rc)
2930 return rc;
2931 rc = call_int_hook(file_alloc_security, file);
2932 if (unlikely(rc))
2933 security_file_free(file);
2934 return rc;
2935 }
2936
2937 /**
2938 * security_file_release() - Perform actions before releasing the file ref
2939 * @file: the file
2940 *
2941 * Perform actions before releasing the last reference to a file.
2942 */
security_file_release(struct file * file)2943 void security_file_release(struct file *file)
2944 {
2945 call_void_hook(file_release, file);
2946 }
2947
2948 /**
2949 * security_file_free() - Free a file's LSM blob
2950 * @file: the file
2951 *
2952 * Deallocate and free any security structures stored in file->f_security.
2953 */
security_file_free(struct file * file)2954 void security_file_free(struct file *file)
2955 {
2956 void *blob;
2957
2958 call_void_hook(file_free_security, file);
2959
2960 blob = file->f_security;
2961 if (blob) {
2962 file->f_security = NULL;
2963 kmem_cache_free(lsm_file_cache, blob);
2964 }
2965 }
2966
2967 /**
2968 * security_file_ioctl() - Check if an ioctl is allowed
2969 * @file: associated file
2970 * @cmd: ioctl cmd
2971 * @arg: ioctl arguments
2972 *
2973 * Check permission for an ioctl operation on @file. Note that @arg sometimes
2974 * represents a user space pointer; in other cases, it may be a simple integer
2975 * value. When @arg represents a user space pointer, it should never be used
2976 * by the security module.
2977 *
2978 * Return: Returns 0 if permission is granted.
2979 */
security_file_ioctl(struct file * file,unsigned int cmd,unsigned long arg)2980 int security_file_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
2981 {
2982 return call_int_hook(file_ioctl, file, cmd, arg);
2983 }
2984 EXPORT_SYMBOL_GPL(security_file_ioctl);
2985
2986 /**
2987 * security_file_ioctl_compat() - Check if an ioctl is allowed in compat mode
2988 * @file: associated file
2989 * @cmd: ioctl cmd
2990 * @arg: ioctl arguments
2991 *
2992 * Compat version of security_file_ioctl() that correctly handles 32-bit
2993 * processes running on 64-bit kernels.
2994 *
2995 * Return: Returns 0 if permission is granted.
2996 */
security_file_ioctl_compat(struct file * file,unsigned int cmd,unsigned long arg)2997 int security_file_ioctl_compat(struct file *file, unsigned int cmd,
2998 unsigned long arg)
2999 {
3000 return call_int_hook(file_ioctl_compat, file, cmd, arg);
3001 }
3002 EXPORT_SYMBOL_GPL(security_file_ioctl_compat);
3003
mmap_prot(struct file * file,unsigned long prot)3004 static inline unsigned long mmap_prot(struct file *file, unsigned long prot)
3005 {
3006 /*
3007 * Does we have PROT_READ and does the application expect
3008 * it to imply PROT_EXEC? If not, nothing to talk about...
3009 */
3010 if ((prot & (PROT_READ | PROT_EXEC)) != PROT_READ)
3011 return prot;
3012 if (!(current->personality & READ_IMPLIES_EXEC))
3013 return prot;
3014 /*
3015 * if that's an anonymous mapping, let it.
3016 */
3017 if (!file)
3018 return prot | PROT_EXEC;
3019 /*
3020 * ditto if it's not on noexec mount, except that on !MMU we need
3021 * NOMMU_MAP_EXEC (== VM_MAYEXEC) in this case
3022 */
3023 if (!path_noexec(&file->f_path)) {
3024 #ifndef CONFIG_MMU
3025 if (file->f_op->mmap_capabilities) {
3026 unsigned caps = file->f_op->mmap_capabilities(file);
3027 if (!(caps & NOMMU_MAP_EXEC))
3028 return prot;
3029 }
3030 #endif
3031 return prot | PROT_EXEC;
3032 }
3033 /* anything on noexec mount won't get PROT_EXEC */
3034 return prot;
3035 }
3036
3037 /**
3038 * security_mmap_file() - Check if mmap'ing a file is allowed
3039 * @file: file
3040 * @prot: protection applied by the kernel
3041 * @flags: flags
3042 *
3043 * Check permissions for a mmap operation. The @file may be NULL, e.g. if
3044 * mapping anonymous memory.
3045 *
3046 * Return: Returns 0 if permission is granted.
3047 */
security_mmap_file(struct file * file,unsigned long prot,unsigned long flags)3048 int security_mmap_file(struct file *file, unsigned long prot,
3049 unsigned long flags)
3050 {
3051 return call_int_hook(mmap_file, file, prot, mmap_prot(file, prot),
3052 flags);
3053 }
3054
3055 /**
3056 * security_mmap_addr() - Check if mmap'ing an address is allowed
3057 * @addr: address
3058 *
3059 * Check permissions for a mmap operation at @addr.
3060 *
3061 * Return: Returns 0 if permission is granted.
3062 */
security_mmap_addr(unsigned long addr)3063 int security_mmap_addr(unsigned long addr)
3064 {
3065 return call_int_hook(mmap_addr, addr);
3066 }
3067
3068 /**
3069 * security_file_mprotect() - Check if changing memory protections is allowed
3070 * @vma: memory region
3071 * @reqprot: application requested protection
3072 * @prot: protection applied by the kernel
3073 *
3074 * Check permissions before changing memory access permissions.
3075 *
3076 * Return: Returns 0 if permission is granted.
3077 */
security_file_mprotect(struct vm_area_struct * vma,unsigned long reqprot,unsigned long prot)3078 int security_file_mprotect(struct vm_area_struct *vma, unsigned long reqprot,
3079 unsigned long prot)
3080 {
3081 return call_int_hook(file_mprotect, vma, reqprot, prot);
3082 }
3083
3084 /**
3085 * security_file_lock() - Check if a file lock is allowed
3086 * @file: file
3087 * @cmd: lock operation (e.g. F_RDLCK, F_WRLCK)
3088 *
3089 * Check permission before performing file locking operations. Note the hook
3090 * mediates both flock and fcntl style locks.
3091 *
3092 * Return: Returns 0 if permission is granted.
3093 */
security_file_lock(struct file * file,unsigned int cmd)3094 int security_file_lock(struct file *file, unsigned int cmd)
3095 {
3096 return call_int_hook(file_lock, file, cmd);
3097 }
3098
3099 /**
3100 * security_file_fcntl() - Check if fcntl() op is allowed
3101 * @file: file
3102 * @cmd: fcntl command
3103 * @arg: command argument
3104 *
3105 * Check permission before allowing the file operation specified by @cmd from
3106 * being performed on the file @file. Note that @arg sometimes represents a
3107 * user space pointer; in other cases, it may be a simple integer value. When
3108 * @arg represents a user space pointer, it should never be used by the
3109 * security module.
3110 *
3111 * Return: Returns 0 if permission is granted.
3112 */
security_file_fcntl(struct file * file,unsigned int cmd,unsigned long arg)3113 int security_file_fcntl(struct file *file, unsigned int cmd, unsigned long arg)
3114 {
3115 return call_int_hook(file_fcntl, file, cmd, arg);
3116 }
3117
3118 /**
3119 * security_file_set_fowner() - Set the file owner info in the LSM blob
3120 * @file: the file
3121 *
3122 * Save owner security information (typically from current->security) in
3123 * file->f_security for later use by the send_sigiotask hook.
3124 *
3125 * This hook is called with file->f_owner.lock held.
3126 *
3127 * Return: Returns 0 on success.
3128 */
security_file_set_fowner(struct file * file)3129 void security_file_set_fowner(struct file *file)
3130 {
3131 call_void_hook(file_set_fowner, file);
3132 }
3133
3134 /**
3135 * security_file_send_sigiotask() - Check if sending SIGIO/SIGURG is allowed
3136 * @tsk: target task
3137 * @fown: signal sender
3138 * @sig: signal to be sent, SIGIO is sent if 0
3139 *
3140 * Check permission for the file owner @fown to send SIGIO or SIGURG to the
3141 * process @tsk. Note that this hook is sometimes called from interrupt. Note
3142 * that the fown_struct, @fown, is never outside the context of a struct file,
3143 * so the file structure (and associated security information) can always be
3144 * obtained: container_of(fown, struct file, f_owner).
3145 *
3146 * Return: Returns 0 if permission is granted.
3147 */
security_file_send_sigiotask(struct task_struct * tsk,struct fown_struct * fown,int sig)3148 int security_file_send_sigiotask(struct task_struct *tsk,
3149 struct fown_struct *fown, int sig)
3150 {
3151 return call_int_hook(file_send_sigiotask, tsk, fown, sig);
3152 }
3153
3154 /**
3155 * security_file_receive() - Check if receiving a file via IPC is allowed
3156 * @file: file being received
3157 *
3158 * This hook allows security modules to control the ability of a process to
3159 * receive an open file descriptor via socket IPC.
3160 *
3161 * Return: Returns 0 if permission is granted.
3162 */
security_file_receive(struct file * file)3163 int security_file_receive(struct file *file)
3164 {
3165 return call_int_hook(file_receive, file);
3166 }
3167
3168 /**
3169 * security_file_open() - Save open() time state for late use by the LSM
3170 * @file:
3171 *
3172 * Save open-time permission checking state for later use upon file_permission,
3173 * and recheck access if anything has changed since inode_permission.
3174 *
3175 * We can check if a file is opened for execution (e.g. execve(2) call), either
3176 * directly or indirectly (e.g. ELF's ld.so) by checking file->f_flags &
3177 * __FMODE_EXEC .
3178 *
3179 * Return: Returns 0 if permission is granted.
3180 */
security_file_open(struct file * file)3181 int security_file_open(struct file *file)
3182 {
3183 return call_int_hook(file_open, file);
3184 }
3185
3186 /**
3187 * security_file_post_open() - Evaluate a file after it has been opened
3188 * @file: the file
3189 * @mask: access mask
3190 *
3191 * Evaluate an opened file and the access mask requested with open(). The hook
3192 * is useful for LSMs that require the file content to be available in order to
3193 * make decisions.
3194 *
3195 * Return: Returns 0 if permission is granted.
3196 */
security_file_post_open(struct file * file,int mask)3197 int security_file_post_open(struct file *file, int mask)
3198 {
3199 return call_int_hook(file_post_open, file, mask);
3200 }
3201 EXPORT_SYMBOL_GPL(security_file_post_open);
3202
3203 /**
3204 * security_file_truncate() - Check if truncating a file is allowed
3205 * @file: file
3206 *
3207 * Check permission before truncating a file, i.e. using ftruncate. Note that
3208 * truncation permission may also be checked based on the path, using the
3209 * @path_truncate hook.
3210 *
3211 * Return: Returns 0 if permission is granted.
3212 */
security_file_truncate(struct file * file)3213 int security_file_truncate(struct file *file)
3214 {
3215 return call_int_hook(file_truncate, file);
3216 }
3217
3218 /**
3219 * security_task_alloc() - Allocate a task's LSM blob
3220 * @task: the task
3221 * @clone_flags: flags indicating what is being shared
3222 *
3223 * Handle allocation of task-related resources.
3224 *
3225 * Return: Returns a zero on success, negative values on failure.
3226 */
security_task_alloc(struct task_struct * task,u64 clone_flags)3227 int security_task_alloc(struct task_struct *task, u64 clone_flags)
3228 {
3229 int rc = lsm_task_alloc(task);
3230
3231 if (rc)
3232 return rc;
3233 rc = call_int_hook(task_alloc, task, clone_flags);
3234 if (unlikely(rc))
3235 security_task_free(task);
3236 return rc;
3237 }
3238
3239 /**
3240 * security_task_free() - Free a task's LSM blob and related resources
3241 * @task: task
3242 *
3243 * Handle release of task-related resources. Note that this can be called from
3244 * interrupt context.
3245 */
security_task_free(struct task_struct * task)3246 void security_task_free(struct task_struct *task)
3247 {
3248 call_void_hook(task_free, task);
3249
3250 kfree(task->security);
3251 task->security = NULL;
3252 }
3253
3254 /**
3255 * security_cred_alloc_blank() - Allocate the min memory to allow cred_transfer
3256 * @cred: credentials
3257 * @gfp: gfp flags
3258 *
3259 * Only allocate sufficient memory and attach to @cred such that
3260 * cred_transfer() will not get ENOMEM.
3261 *
3262 * Return: Returns 0 on success, negative values on failure.
3263 */
security_cred_alloc_blank(struct cred * cred,gfp_t gfp)3264 int security_cred_alloc_blank(struct cred *cred, gfp_t gfp)
3265 {
3266 int rc = lsm_cred_alloc(cred, gfp);
3267
3268 if (rc)
3269 return rc;
3270
3271 rc = call_int_hook(cred_alloc_blank, cred, gfp);
3272 if (unlikely(rc))
3273 security_cred_free(cred);
3274 return rc;
3275 }
3276
3277 /**
3278 * security_cred_free() - Free the cred's LSM blob and associated resources
3279 * @cred: credentials
3280 *
3281 * Deallocate and clear the cred->security field in a set of credentials.
3282 */
security_cred_free(struct cred * cred)3283 void security_cred_free(struct cred *cred)
3284 {
3285 /*
3286 * There is a failure case in prepare_creds() that
3287 * may result in a call here with ->security being NULL.
3288 */
3289 if (unlikely(cred->security == NULL))
3290 return;
3291
3292 call_void_hook(cred_free, cred);
3293
3294 kfree(cred->security);
3295 cred->security = NULL;
3296 }
3297
3298 /**
3299 * security_prepare_creds() - Prepare a new set of credentials
3300 * @new: new credentials
3301 * @old: original credentials
3302 * @gfp: gfp flags
3303 *
3304 * Prepare a new set of credentials by copying the data from the old set.
3305 *
3306 * Return: Returns 0 on success, negative values on failure.
3307 */
security_prepare_creds(struct cred * new,const struct cred * old,gfp_t gfp)3308 int security_prepare_creds(struct cred *new, const struct cred *old, gfp_t gfp)
3309 {
3310 int rc = lsm_cred_alloc(new, gfp);
3311
3312 if (rc)
3313 return rc;
3314
3315 rc = call_int_hook(cred_prepare, new, old, gfp);
3316 if (unlikely(rc))
3317 security_cred_free(new);
3318 return rc;
3319 }
3320
3321 /**
3322 * security_transfer_creds() - Transfer creds
3323 * @new: target credentials
3324 * @old: original credentials
3325 *
3326 * Transfer data from original creds to new creds.
3327 */
security_transfer_creds(struct cred * new,const struct cred * old)3328 void security_transfer_creds(struct cred *new, const struct cred *old)
3329 {
3330 call_void_hook(cred_transfer, new, old);
3331 }
3332
3333 /**
3334 * security_cred_getsecid() - Get the secid from a set of credentials
3335 * @c: credentials
3336 * @secid: secid value
3337 *
3338 * Retrieve the security identifier of the cred structure @c. In case of
3339 * failure, @secid will be set to zero.
3340 */
security_cred_getsecid(const struct cred * c,u32 * secid)3341 void security_cred_getsecid(const struct cred *c, u32 *secid)
3342 {
3343 *secid = 0;
3344 call_void_hook(cred_getsecid, c, secid);
3345 }
3346 EXPORT_SYMBOL(security_cred_getsecid);
3347
3348 /**
3349 * security_cred_getlsmprop() - Get the LSM data from a set of credentials
3350 * @c: credentials
3351 * @prop: destination for the LSM data
3352 *
3353 * Retrieve the security data of the cred structure @c. In case of
3354 * failure, @prop will be cleared.
3355 */
security_cred_getlsmprop(const struct cred * c,struct lsm_prop * prop)3356 void security_cred_getlsmprop(const struct cred *c, struct lsm_prop *prop)
3357 {
3358 lsmprop_init(prop);
3359 call_void_hook(cred_getlsmprop, c, prop);
3360 }
3361 EXPORT_SYMBOL(security_cred_getlsmprop);
3362
3363 /**
3364 * security_kernel_act_as() - Set the kernel credentials to act as secid
3365 * @new: credentials
3366 * @secid: secid
3367 *
3368 * Set the credentials for a kernel service to act as (subjective context).
3369 * The current task must be the one that nominated @secid.
3370 *
3371 * Return: Returns 0 if successful.
3372 */
security_kernel_act_as(struct cred * new,u32 secid)3373 int security_kernel_act_as(struct cred *new, u32 secid)
3374 {
3375 return call_int_hook(kernel_act_as, new, secid);
3376 }
3377
3378 /**
3379 * security_kernel_create_files_as() - Set file creation context using an inode
3380 * @new: target credentials
3381 * @inode: reference inode
3382 *
3383 * Set the file creation context in a set of credentials to be the same as the
3384 * objective context of the specified inode. The current task must be the one
3385 * that nominated @inode.
3386 *
3387 * Return: Returns 0 if successful.
3388 */
security_kernel_create_files_as(struct cred * new,struct inode * inode)3389 int security_kernel_create_files_as(struct cred *new, struct inode *inode)
3390 {
3391 return call_int_hook(kernel_create_files_as, new, inode);
3392 }
3393
3394 /**
3395 * security_kernel_module_request() - Check if loading a module is allowed
3396 * @kmod_name: module name
3397 *
3398 * Ability to trigger the kernel to automatically upcall to userspace for
3399 * userspace to load a kernel module with the given name.
3400 *
3401 * Return: Returns 0 if successful.
3402 */
security_kernel_module_request(char * kmod_name)3403 int security_kernel_module_request(char *kmod_name)
3404 {
3405 return call_int_hook(kernel_module_request, kmod_name);
3406 }
3407
3408 /**
3409 * security_kernel_read_file() - Read a file specified by userspace
3410 * @file: file
3411 * @id: file identifier
3412 * @contents: trust if security_kernel_post_read_file() will be called
3413 *
3414 * Read a file specified by userspace.
3415 *
3416 * Return: Returns 0 if permission is granted.
3417 */
security_kernel_read_file(struct file * file,enum kernel_read_file_id id,bool contents)3418 int security_kernel_read_file(struct file *file, enum kernel_read_file_id id,
3419 bool contents)
3420 {
3421 return call_int_hook(kernel_read_file, file, id, contents);
3422 }
3423 EXPORT_SYMBOL_GPL(security_kernel_read_file);
3424
3425 /**
3426 * security_kernel_post_read_file() - Read a file specified by userspace
3427 * @file: file
3428 * @buf: file contents
3429 * @size: size of file contents
3430 * @id: file identifier
3431 *
3432 * Read a file specified by userspace. This must be paired with a prior call
3433 * to security_kernel_read_file() call that indicated this hook would also be
3434 * called, see security_kernel_read_file() for more information.
3435 *
3436 * Return: Returns 0 if permission is granted.
3437 */
security_kernel_post_read_file(struct file * file,char * buf,loff_t size,enum kernel_read_file_id id)3438 int security_kernel_post_read_file(struct file *file, char *buf, loff_t size,
3439 enum kernel_read_file_id id)
3440 {
3441 return call_int_hook(kernel_post_read_file, file, buf, size, id);
3442 }
3443 EXPORT_SYMBOL_GPL(security_kernel_post_read_file);
3444
3445 /**
3446 * security_kernel_load_data() - Load data provided by userspace
3447 * @id: data identifier
3448 * @contents: true if security_kernel_post_load_data() will be called
3449 *
3450 * Load data provided by userspace.
3451 *
3452 * Return: Returns 0 if permission is granted.
3453 */
security_kernel_load_data(enum kernel_load_data_id id,bool contents)3454 int security_kernel_load_data(enum kernel_load_data_id id, bool contents)
3455 {
3456 return call_int_hook(kernel_load_data, id, contents);
3457 }
3458 EXPORT_SYMBOL_GPL(security_kernel_load_data);
3459
3460 /**
3461 * security_kernel_post_load_data() - Load userspace data from a non-file source
3462 * @buf: data
3463 * @size: size of data
3464 * @id: data identifier
3465 * @description: text description of data, specific to the id value
3466 *
3467 * Load data provided by a non-file source (usually userspace buffer). This
3468 * must be paired with a prior security_kernel_load_data() call that indicated
3469 * this hook would also be called, see security_kernel_load_data() for more
3470 * information.
3471 *
3472 * Return: Returns 0 if permission is granted.
3473 */
security_kernel_post_load_data(char * buf,loff_t size,enum kernel_load_data_id id,char * description)3474 int security_kernel_post_load_data(char *buf, loff_t size,
3475 enum kernel_load_data_id id,
3476 char *description)
3477 {
3478 return call_int_hook(kernel_post_load_data, buf, size, id, description);
3479 }
3480 EXPORT_SYMBOL_GPL(security_kernel_post_load_data);
3481
3482 /**
3483 * security_task_fix_setuid() - Update LSM with new user id attributes
3484 * @new: updated credentials
3485 * @old: credentials being replaced
3486 * @flags: LSM_SETID_* flag values
3487 *
3488 * Update the module's state after setting one or more of the user identity
3489 * attributes of the current process. The @flags parameter indicates which of
3490 * the set*uid system calls invoked this hook. If @new is the set of
3491 * credentials that will be installed. Modifications should be made to this
3492 * rather than to @current->cred.
3493 *
3494 * Return: Returns 0 on success.
3495 */
security_task_fix_setuid(struct cred * new,const struct cred * old,int flags)3496 int security_task_fix_setuid(struct cred *new, const struct cred *old,
3497 int flags)
3498 {
3499 return call_int_hook(task_fix_setuid, new, old, flags);
3500 }
3501
3502 /**
3503 * security_task_fix_setgid() - Update LSM with new group id attributes
3504 * @new: updated credentials
3505 * @old: credentials being replaced
3506 * @flags: LSM_SETID_* flag value
3507 *
3508 * Update the module's state after setting one or more of the group identity
3509 * attributes of the current process. The @flags parameter indicates which of
3510 * the set*gid system calls invoked this hook. @new is the set of credentials
3511 * that will be installed. Modifications should be made to this rather than to
3512 * @current->cred.
3513 *
3514 * Return: Returns 0 on success.
3515 */
security_task_fix_setgid(struct cred * new,const struct cred * old,int flags)3516 int security_task_fix_setgid(struct cred *new, const struct cred *old,
3517 int flags)
3518 {
3519 return call_int_hook(task_fix_setgid, new, old, flags);
3520 }
3521
3522 /**
3523 * security_task_fix_setgroups() - Update LSM with new supplementary groups
3524 * @new: updated credentials
3525 * @old: credentials being replaced
3526 *
3527 * Update the module's state after setting the supplementary group identity
3528 * attributes of the current process. @new is the set of credentials that will
3529 * be installed. Modifications should be made to this rather than to
3530 * @current->cred.
3531 *
3532 * Return: Returns 0 on success.
3533 */
security_task_fix_setgroups(struct cred * new,const struct cred * old)3534 int security_task_fix_setgroups(struct cred *new, const struct cred *old)
3535 {
3536 return call_int_hook(task_fix_setgroups, new, old);
3537 }
3538
3539 /**
3540 * security_task_setpgid() - Check if setting the pgid is allowed
3541 * @p: task being modified
3542 * @pgid: new pgid
3543 *
3544 * Check permission before setting the process group identifier of the process
3545 * @p to @pgid.
3546 *
3547 * Return: Returns 0 if permission is granted.
3548 */
security_task_setpgid(struct task_struct * p,pid_t pgid)3549 int security_task_setpgid(struct task_struct *p, pid_t pgid)
3550 {
3551 return call_int_hook(task_setpgid, p, pgid);
3552 }
3553
3554 /**
3555 * security_task_getpgid() - Check if getting the pgid is allowed
3556 * @p: task
3557 *
3558 * Check permission before getting the process group identifier of the process
3559 * @p.
3560 *
3561 * Return: Returns 0 if permission is granted.
3562 */
security_task_getpgid(struct task_struct * p)3563 int security_task_getpgid(struct task_struct *p)
3564 {
3565 return call_int_hook(task_getpgid, p);
3566 }
3567
3568 /**
3569 * security_task_getsid() - Check if getting the session id is allowed
3570 * @p: task
3571 *
3572 * Check permission before getting the session identifier of the process @p.
3573 *
3574 * Return: Returns 0 if permission is granted.
3575 */
security_task_getsid(struct task_struct * p)3576 int security_task_getsid(struct task_struct *p)
3577 {
3578 return call_int_hook(task_getsid, p);
3579 }
3580
3581 /**
3582 * security_current_getlsmprop_subj() - Current task's subjective LSM data
3583 * @prop: lsm specific information
3584 *
3585 * Retrieve the subjective security identifier of the current task and return
3586 * it in @prop.
3587 */
security_current_getlsmprop_subj(struct lsm_prop * prop)3588 void security_current_getlsmprop_subj(struct lsm_prop *prop)
3589 {
3590 lsmprop_init(prop);
3591 call_void_hook(current_getlsmprop_subj, prop);
3592 }
3593 EXPORT_SYMBOL(security_current_getlsmprop_subj);
3594
3595 /**
3596 * security_task_getlsmprop_obj() - Get a task's objective LSM data
3597 * @p: target task
3598 * @prop: lsm specific information
3599 *
3600 * Retrieve the objective security identifier of the task_struct in @p and
3601 * return it in @prop.
3602 */
security_task_getlsmprop_obj(struct task_struct * p,struct lsm_prop * prop)3603 void security_task_getlsmprop_obj(struct task_struct *p, struct lsm_prop *prop)
3604 {
3605 lsmprop_init(prop);
3606 call_void_hook(task_getlsmprop_obj, p, prop);
3607 }
3608 EXPORT_SYMBOL(security_task_getlsmprop_obj);
3609
3610 /**
3611 * security_task_setnice() - Check if setting a task's nice value is allowed
3612 * @p: target task
3613 * @nice: nice value
3614 *
3615 * Check permission before setting the nice value of @p to @nice.
3616 *
3617 * Return: Returns 0 if permission is granted.
3618 */
security_task_setnice(struct task_struct * p,int nice)3619 int security_task_setnice(struct task_struct *p, int nice)
3620 {
3621 return call_int_hook(task_setnice, p, nice);
3622 }
3623
3624 /**
3625 * security_task_setioprio() - Check if setting a task's ioprio is allowed
3626 * @p: target task
3627 * @ioprio: ioprio value
3628 *
3629 * Check permission before setting the ioprio value of @p to @ioprio.
3630 *
3631 * Return: Returns 0 if permission is granted.
3632 */
security_task_setioprio(struct task_struct * p,int ioprio)3633 int security_task_setioprio(struct task_struct *p, int ioprio)
3634 {
3635 return call_int_hook(task_setioprio, p, ioprio);
3636 }
3637
3638 /**
3639 * security_task_getioprio() - Check if getting a task's ioprio is allowed
3640 * @p: task
3641 *
3642 * Check permission before getting the ioprio value of @p.
3643 *
3644 * Return: Returns 0 if permission is granted.
3645 */
security_task_getioprio(struct task_struct * p)3646 int security_task_getioprio(struct task_struct *p)
3647 {
3648 return call_int_hook(task_getioprio, p);
3649 }
3650
3651 /**
3652 * security_task_prlimit() - Check if get/setting resources limits is allowed
3653 * @cred: current task credentials
3654 * @tcred: target task credentials
3655 * @flags: LSM_PRLIMIT_* flag bits indicating a get/set/both
3656 *
3657 * Check permission before getting and/or setting the resource limits of
3658 * another task.
3659 *
3660 * Return: Returns 0 if permission is granted.
3661 */
security_task_prlimit(const struct cred * cred,const struct cred * tcred,unsigned int flags)3662 int security_task_prlimit(const struct cred *cred, const struct cred *tcred,
3663 unsigned int flags)
3664 {
3665 return call_int_hook(task_prlimit, cred, tcred, flags);
3666 }
3667
3668 /**
3669 * security_task_setrlimit() - Check if setting a new rlimit value is allowed
3670 * @p: target task's group leader
3671 * @resource: resource whose limit is being set
3672 * @new_rlim: new resource limit
3673 *
3674 * Check permission before setting the resource limits of process @p for
3675 * @resource to @new_rlim. The old resource limit values can be examined by
3676 * dereferencing (p->signal->rlim + resource).
3677 *
3678 * Return: Returns 0 if permission is granted.
3679 */
security_task_setrlimit(struct task_struct * p,unsigned int resource,struct rlimit * new_rlim)3680 int security_task_setrlimit(struct task_struct *p, unsigned int resource,
3681 struct rlimit *new_rlim)
3682 {
3683 return call_int_hook(task_setrlimit, p, resource, new_rlim);
3684 }
3685
3686 /**
3687 * security_task_setscheduler() - Check if setting sched policy/param is allowed
3688 * @p: target task
3689 *
3690 * Check permission before setting scheduling policy and/or parameters of
3691 * process @p.
3692 *
3693 * Return: Returns 0 if permission is granted.
3694 */
security_task_setscheduler(struct task_struct * p)3695 int security_task_setscheduler(struct task_struct *p)
3696 {
3697 return call_int_hook(task_setscheduler, p);
3698 }
3699
3700 /**
3701 * security_task_getscheduler() - Check if getting scheduling info is allowed
3702 * @p: target task
3703 *
3704 * Check permission before obtaining scheduling information for process @p.
3705 *
3706 * Return: Returns 0 if permission is granted.
3707 */
security_task_getscheduler(struct task_struct * p)3708 int security_task_getscheduler(struct task_struct *p)
3709 {
3710 return call_int_hook(task_getscheduler, p);
3711 }
3712
3713 /**
3714 * security_task_movememory() - Check if moving memory is allowed
3715 * @p: task
3716 *
3717 * Check permission before moving memory owned by process @p.
3718 *
3719 * Return: Returns 0 if permission is granted.
3720 */
security_task_movememory(struct task_struct * p)3721 int security_task_movememory(struct task_struct *p)
3722 {
3723 return call_int_hook(task_movememory, p);
3724 }
3725
3726 /**
3727 * security_task_kill() - Check if sending a signal is allowed
3728 * @p: target process
3729 * @info: signal information
3730 * @sig: signal value
3731 * @cred: credentials of the signal sender, NULL if @current
3732 *
3733 * Check permission before sending signal @sig to @p. @info can be NULL, the
3734 * constant 1, or a pointer to a kernel_siginfo structure. If @info is 1 or
3735 * SI_FROMKERNEL(info) is true, then the signal should be viewed as coming from
3736 * the kernel and should typically be permitted. SIGIO signals are handled
3737 * separately by the send_sigiotask hook in file_security_ops.
3738 *
3739 * Return: Returns 0 if permission is granted.
3740 */
security_task_kill(struct task_struct * p,struct kernel_siginfo * info,int sig,const struct cred * cred)3741 int security_task_kill(struct task_struct *p, struct kernel_siginfo *info,
3742 int sig, const struct cred *cred)
3743 {
3744 return call_int_hook(task_kill, p, info, sig, cred);
3745 }
3746
3747 /**
3748 * security_task_prctl() - Check if a prctl op is allowed
3749 * @option: operation
3750 * @arg2: argument
3751 * @arg3: argument
3752 * @arg4: argument
3753 * @arg5: argument
3754 *
3755 * Check permission before performing a process control operation on the
3756 * current process.
3757 *
3758 * Return: Return -ENOSYS if no-one wanted to handle this op, any other value
3759 * to cause prctl() to return immediately with that value.
3760 */
security_task_prctl(int option,unsigned long arg2,unsigned long arg3,unsigned long arg4,unsigned long arg5)3761 int security_task_prctl(int option, unsigned long arg2, unsigned long arg3,
3762 unsigned long arg4, unsigned long arg5)
3763 {
3764 int thisrc;
3765 int rc = LSM_RET_DEFAULT(task_prctl);
3766 struct lsm_static_call *scall;
3767
3768 lsm_for_each_hook(scall, task_prctl) {
3769 thisrc = scall->hl->hook.task_prctl(option, arg2, arg3, arg4, arg5);
3770 if (thisrc != LSM_RET_DEFAULT(task_prctl)) {
3771 rc = thisrc;
3772 if (thisrc != 0)
3773 break;
3774 }
3775 }
3776 return rc;
3777 }
3778
3779 /**
3780 * security_task_to_inode() - Set the security attributes of a task's inode
3781 * @p: task
3782 * @inode: inode
3783 *
3784 * Set the security attributes for an inode based on an associated task's
3785 * security attributes, e.g. for /proc/pid inodes.
3786 */
security_task_to_inode(struct task_struct * p,struct inode * inode)3787 void security_task_to_inode(struct task_struct *p, struct inode *inode)
3788 {
3789 call_void_hook(task_to_inode, p, inode);
3790 }
3791
3792 /**
3793 * security_create_user_ns() - Check if creating a new userns is allowed
3794 * @cred: prepared creds
3795 *
3796 * Check permission prior to creating a new user namespace.
3797 *
3798 * Return: Returns 0 if successful, otherwise < 0 error code.
3799 */
security_create_user_ns(const struct cred * cred)3800 int security_create_user_ns(const struct cred *cred)
3801 {
3802 return call_int_hook(userns_create, cred);
3803 }
3804
3805 /**
3806 * security_ipc_permission() - Check if sysv ipc access is allowed
3807 * @ipcp: ipc permission structure
3808 * @flag: requested permissions
3809 *
3810 * Check permissions for access to IPC.
3811 *
3812 * Return: Returns 0 if permission is granted.
3813 */
security_ipc_permission(struct kern_ipc_perm * ipcp,short flag)3814 int security_ipc_permission(struct kern_ipc_perm *ipcp, short flag)
3815 {
3816 return call_int_hook(ipc_permission, ipcp, flag);
3817 }
3818
3819 /**
3820 * security_ipc_getlsmprop() - Get the sysv ipc object LSM data
3821 * @ipcp: ipc permission structure
3822 * @prop: pointer to lsm information
3823 *
3824 * Get the lsm information associated with the ipc object.
3825 */
3826
security_ipc_getlsmprop(struct kern_ipc_perm * ipcp,struct lsm_prop * prop)3827 void security_ipc_getlsmprop(struct kern_ipc_perm *ipcp, struct lsm_prop *prop)
3828 {
3829 lsmprop_init(prop);
3830 call_void_hook(ipc_getlsmprop, ipcp, prop);
3831 }
3832
3833 /**
3834 * security_msg_msg_alloc() - Allocate a sysv ipc message LSM blob
3835 * @msg: message structure
3836 *
3837 * Allocate and attach a security structure to the msg->security field. The
3838 * security field is initialized to NULL when the structure is first created.
3839 *
3840 * Return: Return 0 if operation was successful and permission is granted.
3841 */
security_msg_msg_alloc(struct msg_msg * msg)3842 int security_msg_msg_alloc(struct msg_msg *msg)
3843 {
3844 int rc = lsm_msg_msg_alloc(msg);
3845
3846 if (unlikely(rc))
3847 return rc;
3848 rc = call_int_hook(msg_msg_alloc_security, msg);
3849 if (unlikely(rc))
3850 security_msg_msg_free(msg);
3851 return rc;
3852 }
3853
3854 /**
3855 * security_msg_msg_free() - Free a sysv ipc message LSM blob
3856 * @msg: message structure
3857 *
3858 * Deallocate the security structure for this message.
3859 */
security_msg_msg_free(struct msg_msg * msg)3860 void security_msg_msg_free(struct msg_msg *msg)
3861 {
3862 call_void_hook(msg_msg_free_security, msg);
3863 kfree(msg->security);
3864 msg->security = NULL;
3865 }
3866
3867 /**
3868 * security_msg_queue_alloc() - Allocate a sysv ipc msg queue LSM blob
3869 * @msq: sysv ipc permission structure
3870 *
3871 * Allocate and attach a security structure to @msg. The security field is
3872 * initialized to NULL when the structure is first created.
3873 *
3874 * Return: Returns 0 if operation was successful and permission is granted.
3875 */
security_msg_queue_alloc(struct kern_ipc_perm * msq)3876 int security_msg_queue_alloc(struct kern_ipc_perm *msq)
3877 {
3878 int rc = lsm_ipc_alloc(msq);
3879
3880 if (unlikely(rc))
3881 return rc;
3882 rc = call_int_hook(msg_queue_alloc_security, msq);
3883 if (unlikely(rc))
3884 security_msg_queue_free(msq);
3885 return rc;
3886 }
3887
3888 /**
3889 * security_msg_queue_free() - Free a sysv ipc msg queue LSM blob
3890 * @msq: sysv ipc permission structure
3891 *
3892 * Deallocate security field @perm->security for the message queue.
3893 */
security_msg_queue_free(struct kern_ipc_perm * msq)3894 void security_msg_queue_free(struct kern_ipc_perm *msq)
3895 {
3896 call_void_hook(msg_queue_free_security, msq);
3897 kfree(msq->security);
3898 msq->security = NULL;
3899 }
3900
3901 /**
3902 * security_msg_queue_associate() - Check if a msg queue operation is allowed
3903 * @msq: sysv ipc permission structure
3904 * @msqflg: operation flags
3905 *
3906 * Check permission when a message queue is requested through the msgget system
3907 * call. This hook is only called when returning the message queue identifier
3908 * for an existing message queue, not when a new message queue is created.
3909 *
3910 * Return: Return 0 if permission is granted.
3911 */
security_msg_queue_associate(struct kern_ipc_perm * msq,int msqflg)3912 int security_msg_queue_associate(struct kern_ipc_perm *msq, int msqflg)
3913 {
3914 return call_int_hook(msg_queue_associate, msq, msqflg);
3915 }
3916
3917 /**
3918 * security_msg_queue_msgctl() - Check if a msg queue operation is allowed
3919 * @msq: sysv ipc permission structure
3920 * @cmd: operation
3921 *
3922 * Check permission when a message control operation specified by @cmd is to be
3923 * performed on the message queue with permissions.
3924 *
3925 * Return: Returns 0 if permission is granted.
3926 */
security_msg_queue_msgctl(struct kern_ipc_perm * msq,int cmd)3927 int security_msg_queue_msgctl(struct kern_ipc_perm *msq, int cmd)
3928 {
3929 return call_int_hook(msg_queue_msgctl, msq, cmd);
3930 }
3931
3932 /**
3933 * security_msg_queue_msgsnd() - Check if sending a sysv ipc message is allowed
3934 * @msq: sysv ipc permission structure
3935 * @msg: message
3936 * @msqflg: operation flags
3937 *
3938 * Check permission before a message, @msg, is enqueued on the message queue
3939 * with permissions specified in @msq.
3940 *
3941 * Return: Returns 0 if permission is granted.
3942 */
security_msg_queue_msgsnd(struct kern_ipc_perm * msq,struct msg_msg * msg,int msqflg)3943 int security_msg_queue_msgsnd(struct kern_ipc_perm *msq,
3944 struct msg_msg *msg, int msqflg)
3945 {
3946 return call_int_hook(msg_queue_msgsnd, msq, msg, msqflg);
3947 }
3948
3949 /**
3950 * security_msg_queue_msgrcv() - Check if receiving a sysv ipc msg is allowed
3951 * @msq: sysv ipc permission structure
3952 * @msg: message
3953 * @target: target task
3954 * @type: type of message requested
3955 * @mode: operation flags
3956 *
3957 * Check permission before a message, @msg, is removed from the message queue.
3958 * The @target task structure contains a pointer to the process that will be
3959 * receiving the message (not equal to the current process when inline receives
3960 * are being performed).
3961 *
3962 * Return: Returns 0 if permission is granted.
3963 */
security_msg_queue_msgrcv(struct kern_ipc_perm * msq,struct msg_msg * msg,struct task_struct * target,long type,int mode)3964 int security_msg_queue_msgrcv(struct kern_ipc_perm *msq, struct msg_msg *msg,
3965 struct task_struct *target, long type, int mode)
3966 {
3967 return call_int_hook(msg_queue_msgrcv, msq, msg, target, type, mode);
3968 }
3969
3970 /**
3971 * security_shm_alloc() - Allocate a sysv shm LSM blob
3972 * @shp: sysv ipc permission structure
3973 *
3974 * Allocate and attach a security structure to the @shp security field. The
3975 * security field is initialized to NULL when the structure is first created.
3976 *
3977 * Return: Returns 0 if operation was successful and permission is granted.
3978 */
security_shm_alloc(struct kern_ipc_perm * shp)3979 int security_shm_alloc(struct kern_ipc_perm *shp)
3980 {
3981 int rc = lsm_ipc_alloc(shp);
3982
3983 if (unlikely(rc))
3984 return rc;
3985 rc = call_int_hook(shm_alloc_security, shp);
3986 if (unlikely(rc))
3987 security_shm_free(shp);
3988 return rc;
3989 }
3990
3991 /**
3992 * security_shm_free() - Free a sysv shm LSM blob
3993 * @shp: sysv ipc permission structure
3994 *
3995 * Deallocate the security structure @perm->security for the memory segment.
3996 */
security_shm_free(struct kern_ipc_perm * shp)3997 void security_shm_free(struct kern_ipc_perm *shp)
3998 {
3999 call_void_hook(shm_free_security, shp);
4000 kfree(shp->security);
4001 shp->security = NULL;
4002 }
4003
4004 /**
4005 * security_shm_associate() - Check if a sysv shm operation is allowed
4006 * @shp: sysv ipc permission structure
4007 * @shmflg: operation flags
4008 *
4009 * Check permission when a shared memory region is requested through the shmget
4010 * system call. This hook is only called when returning the shared memory
4011 * region identifier for an existing region, not when a new shared memory
4012 * region is created.
4013 *
4014 * Return: Returns 0 if permission is granted.
4015 */
security_shm_associate(struct kern_ipc_perm * shp,int shmflg)4016 int security_shm_associate(struct kern_ipc_perm *shp, int shmflg)
4017 {
4018 return call_int_hook(shm_associate, shp, shmflg);
4019 }
4020
4021 /**
4022 * security_shm_shmctl() - Check if a sysv shm operation is allowed
4023 * @shp: sysv ipc permission structure
4024 * @cmd: operation
4025 *
4026 * Check permission when a shared memory control operation specified by @cmd is
4027 * to be performed on the shared memory region with permissions in @shp.
4028 *
4029 * Return: Return 0 if permission is granted.
4030 */
security_shm_shmctl(struct kern_ipc_perm * shp,int cmd)4031 int security_shm_shmctl(struct kern_ipc_perm *shp, int cmd)
4032 {
4033 return call_int_hook(shm_shmctl, shp, cmd);
4034 }
4035
4036 /**
4037 * security_shm_shmat() - Check if a sysv shm attach operation is allowed
4038 * @shp: sysv ipc permission structure
4039 * @shmaddr: address of memory region to attach
4040 * @shmflg: operation flags
4041 *
4042 * Check permissions prior to allowing the shmat system call to attach the
4043 * shared memory segment with permissions @shp to the data segment of the
4044 * calling process. The attaching address is specified by @shmaddr.
4045 *
4046 * Return: Returns 0 if permission is granted.
4047 */
security_shm_shmat(struct kern_ipc_perm * shp,char __user * shmaddr,int shmflg)4048 int security_shm_shmat(struct kern_ipc_perm *shp,
4049 char __user *shmaddr, int shmflg)
4050 {
4051 return call_int_hook(shm_shmat, shp, shmaddr, shmflg);
4052 }
4053
4054 /**
4055 * security_sem_alloc() - Allocate a sysv semaphore LSM blob
4056 * @sma: sysv ipc permission structure
4057 *
4058 * Allocate and attach a security structure to the @sma security field. The
4059 * security field is initialized to NULL when the structure is first created.
4060 *
4061 * Return: Returns 0 if operation was successful and permission is granted.
4062 */
security_sem_alloc(struct kern_ipc_perm * sma)4063 int security_sem_alloc(struct kern_ipc_perm *sma)
4064 {
4065 int rc = lsm_ipc_alloc(sma);
4066
4067 if (unlikely(rc))
4068 return rc;
4069 rc = call_int_hook(sem_alloc_security, sma);
4070 if (unlikely(rc))
4071 security_sem_free(sma);
4072 return rc;
4073 }
4074
4075 /**
4076 * security_sem_free() - Free a sysv semaphore LSM blob
4077 * @sma: sysv ipc permission structure
4078 *
4079 * Deallocate security structure @sma->security for the semaphore.
4080 */
security_sem_free(struct kern_ipc_perm * sma)4081 void security_sem_free(struct kern_ipc_perm *sma)
4082 {
4083 call_void_hook(sem_free_security, sma);
4084 kfree(sma->security);
4085 sma->security = NULL;
4086 }
4087
4088 /**
4089 * security_sem_associate() - Check if a sysv semaphore operation is allowed
4090 * @sma: sysv ipc permission structure
4091 * @semflg: operation flags
4092 *
4093 * Check permission when a semaphore is requested through the semget system
4094 * call. This hook is only called when returning the semaphore identifier for
4095 * an existing semaphore, not when a new one must be created.
4096 *
4097 * Return: Returns 0 if permission is granted.
4098 */
security_sem_associate(struct kern_ipc_perm * sma,int semflg)4099 int security_sem_associate(struct kern_ipc_perm *sma, int semflg)
4100 {
4101 return call_int_hook(sem_associate, sma, semflg);
4102 }
4103
4104 /**
4105 * security_sem_semctl() - Check if a sysv semaphore operation is allowed
4106 * @sma: sysv ipc permission structure
4107 * @cmd: operation
4108 *
4109 * Check permission when a semaphore operation specified by @cmd is to be
4110 * performed on the semaphore.
4111 *
4112 * Return: Returns 0 if permission is granted.
4113 */
security_sem_semctl(struct kern_ipc_perm * sma,int cmd)4114 int security_sem_semctl(struct kern_ipc_perm *sma, int cmd)
4115 {
4116 return call_int_hook(sem_semctl, sma, cmd);
4117 }
4118
4119 /**
4120 * security_sem_semop() - Check if a sysv semaphore operation is allowed
4121 * @sma: sysv ipc permission structure
4122 * @sops: operations to perform
4123 * @nsops: number of operations
4124 * @alter: flag indicating changes will be made
4125 *
4126 * Check permissions before performing operations on members of the semaphore
4127 * set. If the @alter flag is nonzero, the semaphore set may be modified.
4128 *
4129 * Return: Returns 0 if permission is granted.
4130 */
security_sem_semop(struct kern_ipc_perm * sma,struct sembuf * sops,unsigned nsops,int alter)4131 int security_sem_semop(struct kern_ipc_perm *sma, struct sembuf *sops,
4132 unsigned nsops, int alter)
4133 {
4134 return call_int_hook(sem_semop, sma, sops, nsops, alter);
4135 }
4136
4137 /**
4138 * security_d_instantiate() - Populate an inode's LSM state based on a dentry
4139 * @dentry: dentry
4140 * @inode: inode
4141 *
4142 * Fill in @inode security information for a @dentry if allowed.
4143 */
security_d_instantiate(struct dentry * dentry,struct inode * inode)4144 void security_d_instantiate(struct dentry *dentry, struct inode *inode)
4145 {
4146 if (unlikely(inode && IS_PRIVATE(inode)))
4147 return;
4148 call_void_hook(d_instantiate, dentry, inode);
4149 }
4150 EXPORT_SYMBOL(security_d_instantiate);
4151
4152 /*
4153 * Please keep this in sync with it's counterpart in security/lsm_syscalls.c
4154 */
4155
4156 /**
4157 * security_getselfattr - Read an LSM attribute of the current process.
4158 * @attr: which attribute to return
4159 * @uctx: the user-space destination for the information, or NULL
4160 * @size: pointer to the size of space available to receive the data
4161 * @flags: special handling options. LSM_FLAG_SINGLE indicates that only
4162 * attributes associated with the LSM identified in the passed @ctx be
4163 * reported.
4164 *
4165 * A NULL value for @uctx can be used to get both the number of attributes
4166 * and the size of the data.
4167 *
4168 * Returns the number of attributes found on success, negative value
4169 * on error. @size is reset to the total size of the data.
4170 * If @size is insufficient to contain the data -E2BIG is returned.
4171 */
security_getselfattr(unsigned int attr,struct lsm_ctx __user * uctx,u32 __user * size,u32 flags)4172 int security_getselfattr(unsigned int attr, struct lsm_ctx __user *uctx,
4173 u32 __user *size, u32 flags)
4174 {
4175 struct lsm_static_call *scall;
4176 struct lsm_ctx lctx = { .id = LSM_ID_UNDEF, };
4177 u8 __user *base = (u8 __user *)uctx;
4178 u32 entrysize;
4179 u32 total = 0;
4180 u32 left;
4181 bool toobig = false;
4182 bool single = false;
4183 int count = 0;
4184 int rc;
4185
4186 if (attr == LSM_ATTR_UNDEF)
4187 return -EINVAL;
4188 if (size == NULL)
4189 return -EINVAL;
4190 if (get_user(left, size))
4191 return -EFAULT;
4192
4193 if (flags) {
4194 /*
4195 * Only flag supported is LSM_FLAG_SINGLE
4196 */
4197 if (flags != LSM_FLAG_SINGLE || !uctx)
4198 return -EINVAL;
4199 if (copy_from_user(&lctx, uctx, sizeof(lctx)))
4200 return -EFAULT;
4201 /*
4202 * If the LSM ID isn't specified it is an error.
4203 */
4204 if (lctx.id == LSM_ID_UNDEF)
4205 return -EINVAL;
4206 single = true;
4207 }
4208
4209 /*
4210 * In the usual case gather all the data from the LSMs.
4211 * In the single case only get the data from the LSM specified.
4212 */
4213 lsm_for_each_hook(scall, getselfattr) {
4214 if (single && lctx.id != scall->hl->lsmid->id)
4215 continue;
4216 entrysize = left;
4217 if (base)
4218 uctx = (struct lsm_ctx __user *)(base + total);
4219 rc = scall->hl->hook.getselfattr(attr, uctx, &entrysize, flags);
4220 if (rc == -EOPNOTSUPP)
4221 continue;
4222 if (rc == -E2BIG) {
4223 rc = 0;
4224 left = 0;
4225 toobig = true;
4226 } else if (rc < 0)
4227 return rc;
4228 else
4229 left -= entrysize;
4230
4231 total += entrysize;
4232 count += rc;
4233 if (single)
4234 break;
4235 }
4236 if (put_user(total, size))
4237 return -EFAULT;
4238 if (toobig)
4239 return -E2BIG;
4240 if (count == 0)
4241 return LSM_RET_DEFAULT(getselfattr);
4242 return count;
4243 }
4244
4245 /*
4246 * Please keep this in sync with it's counterpart in security/lsm_syscalls.c
4247 */
4248
4249 /**
4250 * security_setselfattr - Set an LSM attribute on the current process.
4251 * @attr: which attribute to set
4252 * @uctx: the user-space source for the information
4253 * @size: the size of the data
4254 * @flags: reserved for future use, must be 0
4255 *
4256 * Set an LSM attribute for the current process. The LSM, attribute
4257 * and new value are included in @uctx.
4258 *
4259 * Returns 0 on success, -EINVAL if the input is inconsistent, -EFAULT
4260 * if the user buffer is inaccessible, E2BIG if size is too big, or an
4261 * LSM specific failure.
4262 */
security_setselfattr(unsigned int attr,struct lsm_ctx __user * uctx,u32 size,u32 flags)4263 int security_setselfattr(unsigned int attr, struct lsm_ctx __user *uctx,
4264 u32 size, u32 flags)
4265 {
4266 struct lsm_static_call *scall;
4267 struct lsm_ctx *lctx;
4268 int rc = LSM_RET_DEFAULT(setselfattr);
4269 u64 required_len;
4270
4271 if (flags)
4272 return -EINVAL;
4273 if (size < sizeof(*lctx))
4274 return -EINVAL;
4275 if (size > PAGE_SIZE)
4276 return -E2BIG;
4277
4278 lctx = memdup_user(uctx, size);
4279 if (IS_ERR(lctx))
4280 return PTR_ERR(lctx);
4281
4282 if (size < lctx->len ||
4283 check_add_overflow(sizeof(*lctx), lctx->ctx_len, &required_len) ||
4284 lctx->len < required_len) {
4285 rc = -EINVAL;
4286 goto free_out;
4287 }
4288
4289 lsm_for_each_hook(scall, setselfattr)
4290 if ((scall->hl->lsmid->id) == lctx->id) {
4291 rc = scall->hl->hook.setselfattr(attr, lctx, size, flags);
4292 break;
4293 }
4294
4295 free_out:
4296 kfree(lctx);
4297 return rc;
4298 }
4299
4300 /**
4301 * security_getprocattr() - Read an attribute for a task
4302 * @p: the task
4303 * @lsmid: LSM identification
4304 * @name: attribute name
4305 * @value: attribute value
4306 *
4307 * Read attribute @name for task @p and store it into @value if allowed.
4308 *
4309 * Return: Returns the length of @value on success, a negative value otherwise.
4310 */
security_getprocattr(struct task_struct * p,int lsmid,const char * name,char ** value)4311 int security_getprocattr(struct task_struct *p, int lsmid, const char *name,
4312 char **value)
4313 {
4314 struct lsm_static_call *scall;
4315
4316 lsm_for_each_hook(scall, getprocattr) {
4317 if (lsmid != 0 && lsmid != scall->hl->lsmid->id)
4318 continue;
4319 return scall->hl->hook.getprocattr(p, name, value);
4320 }
4321 return LSM_RET_DEFAULT(getprocattr);
4322 }
4323
4324 /**
4325 * security_setprocattr() - Set an attribute for a task
4326 * @lsmid: LSM identification
4327 * @name: attribute name
4328 * @value: attribute value
4329 * @size: attribute value size
4330 *
4331 * Write (set) the current task's attribute @name to @value, size @size if
4332 * allowed.
4333 *
4334 * Return: Returns bytes written on success, a negative value otherwise.
4335 */
security_setprocattr(int lsmid,const char * name,void * value,size_t size)4336 int security_setprocattr(int lsmid, const char *name, void *value, size_t size)
4337 {
4338 struct lsm_static_call *scall;
4339
4340 lsm_for_each_hook(scall, setprocattr) {
4341 if (lsmid != 0 && lsmid != scall->hl->lsmid->id)
4342 continue;
4343 return scall->hl->hook.setprocattr(name, value, size);
4344 }
4345 return LSM_RET_DEFAULT(setprocattr);
4346 }
4347
4348 /**
4349 * security_ismaclabel() - Check if the named attribute is a MAC label
4350 * @name: full extended attribute name
4351 *
4352 * Check if the extended attribute specified by @name represents a MAC label.
4353 *
4354 * Return: Returns 1 if name is a MAC attribute otherwise returns 0.
4355 */
security_ismaclabel(const char * name)4356 int security_ismaclabel(const char *name)
4357 {
4358 return call_int_hook(ismaclabel, name);
4359 }
4360 EXPORT_SYMBOL(security_ismaclabel);
4361
4362 /**
4363 * security_secid_to_secctx() - Convert a secid to a secctx
4364 * @secid: secid
4365 * @cp: the LSM context
4366 *
4367 * Convert secid to security context. If @cp is NULL the length of the
4368 * result will be returned, but no data will be returned. This
4369 * does mean that the length could change between calls to check the length and
4370 * the next call which actually allocates and returns the data.
4371 *
4372 * Return: Return length of data on success, error on failure.
4373 */
security_secid_to_secctx(u32 secid,struct lsm_context * cp)4374 int security_secid_to_secctx(u32 secid, struct lsm_context *cp)
4375 {
4376 return call_int_hook(secid_to_secctx, secid, cp);
4377 }
4378 EXPORT_SYMBOL(security_secid_to_secctx);
4379
4380 /**
4381 * security_lsmprop_to_secctx() - Convert a lsm_prop to a secctx
4382 * @prop: lsm specific information
4383 * @cp: the LSM context
4384 * @lsmid: which security module to report
4385 *
4386 * Convert a @prop entry to security context. If @cp is NULL the
4387 * length of the result will be returned. This does mean that the
4388 * length could change between calls to check the length and the
4389 * next call which actually allocates and returns the @cp.
4390 *
4391 * @lsmid identifies which LSM should supply the context.
4392 * A value of LSM_ID_UNDEF indicates that the first LSM suppling
4393 * the hook should be used. This is used in cases where the
4394 * ID of the supplying LSM is unambiguous.
4395 *
4396 * Return: Return length of data on success, error on failure.
4397 */
security_lsmprop_to_secctx(struct lsm_prop * prop,struct lsm_context * cp,int lsmid)4398 int security_lsmprop_to_secctx(struct lsm_prop *prop, struct lsm_context *cp,
4399 int lsmid)
4400 {
4401 struct lsm_static_call *scall;
4402
4403 lsm_for_each_hook(scall, lsmprop_to_secctx) {
4404 if (lsmid != LSM_ID_UNDEF && lsmid != scall->hl->lsmid->id)
4405 continue;
4406 return scall->hl->hook.lsmprop_to_secctx(prop, cp);
4407 }
4408 return LSM_RET_DEFAULT(lsmprop_to_secctx);
4409 }
4410 EXPORT_SYMBOL(security_lsmprop_to_secctx);
4411
4412 /**
4413 * security_secctx_to_secid() - Convert a secctx to a secid
4414 * @secdata: secctx
4415 * @seclen: length of secctx
4416 * @secid: secid
4417 *
4418 * Convert security context to secid.
4419 *
4420 * Return: Returns 0 on success, error on failure.
4421 */
security_secctx_to_secid(const char * secdata,u32 seclen,u32 * secid)4422 int security_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
4423 {
4424 *secid = 0;
4425 return call_int_hook(secctx_to_secid, secdata, seclen, secid);
4426 }
4427 EXPORT_SYMBOL(security_secctx_to_secid);
4428
4429 /**
4430 * security_release_secctx() - Free a secctx buffer
4431 * @cp: the security context
4432 *
4433 * Release the security context.
4434 */
security_release_secctx(struct lsm_context * cp)4435 void security_release_secctx(struct lsm_context *cp)
4436 {
4437 call_void_hook(release_secctx, cp);
4438 memset(cp, 0, sizeof(*cp));
4439 }
4440 EXPORT_SYMBOL(security_release_secctx);
4441
4442 /**
4443 * security_inode_invalidate_secctx() - Invalidate an inode's security label
4444 * @inode: inode
4445 *
4446 * Notify the security module that it must revalidate the security context of
4447 * an inode.
4448 */
security_inode_invalidate_secctx(struct inode * inode)4449 void security_inode_invalidate_secctx(struct inode *inode)
4450 {
4451 call_void_hook(inode_invalidate_secctx, inode);
4452 }
4453 EXPORT_SYMBOL(security_inode_invalidate_secctx);
4454
4455 /**
4456 * security_inode_notifysecctx() - Notify the LSM of an inode's security label
4457 * @inode: inode
4458 * @ctx: secctx
4459 * @ctxlen: length of secctx
4460 *
4461 * Notify the security module of what the security context of an inode should
4462 * be. Initializes the incore security context managed by the security module
4463 * for this inode. Example usage: NFS client invokes this hook to initialize
4464 * the security context in its incore inode to the value provided by the server
4465 * for the file when the server returned the file's attributes to the client.
4466 * Must be called with inode->i_mutex locked.
4467 *
4468 * Return: Returns 0 on success, error on failure.
4469 */
security_inode_notifysecctx(struct inode * inode,void * ctx,u32 ctxlen)4470 int security_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen)
4471 {
4472 return call_int_hook(inode_notifysecctx, inode, ctx, ctxlen);
4473 }
4474 EXPORT_SYMBOL(security_inode_notifysecctx);
4475
4476 /**
4477 * security_inode_setsecctx() - Change the security label of an inode
4478 * @dentry: inode
4479 * @ctx: secctx
4480 * @ctxlen: length of secctx
4481 *
4482 * Change the security context of an inode. Updates the incore security
4483 * context managed by the security module and invokes the fs code as needed
4484 * (via __vfs_setxattr_noperm) to update any backing xattrs that represent the
4485 * context. Example usage: NFS server invokes this hook to change the security
4486 * context in its incore inode and on the backing filesystem to a value
4487 * provided by the client on a SETATTR operation. Must be called with
4488 * inode->i_mutex locked.
4489 *
4490 * Return: Returns 0 on success, error on failure.
4491 */
security_inode_setsecctx(struct dentry * dentry,void * ctx,u32 ctxlen)4492 int security_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen)
4493 {
4494 return call_int_hook(inode_setsecctx, dentry, ctx, ctxlen);
4495 }
4496 EXPORT_SYMBOL(security_inode_setsecctx);
4497
4498 /**
4499 * security_inode_getsecctx() - Get the security label of an inode
4500 * @inode: inode
4501 * @cp: security context
4502 *
4503 * On success, returns 0 and fills out @cp with the security context
4504 * for the given @inode.
4505 *
4506 * Return: Returns 0 on success, error on failure.
4507 */
security_inode_getsecctx(struct inode * inode,struct lsm_context * cp)4508 int security_inode_getsecctx(struct inode *inode, struct lsm_context *cp)
4509 {
4510 memset(cp, 0, sizeof(*cp));
4511 return call_int_hook(inode_getsecctx, inode, cp);
4512 }
4513 EXPORT_SYMBOL(security_inode_getsecctx);
4514
4515 #ifdef CONFIG_WATCH_QUEUE
4516 /**
4517 * security_post_notification() - Check if a watch notification can be posted
4518 * @w_cred: credentials of the task that set the watch
4519 * @cred: credentials of the task which triggered the watch
4520 * @n: the notification
4521 *
4522 * Check to see if a watch notification can be posted to a particular queue.
4523 *
4524 * Return: Returns 0 if permission is granted.
4525 */
security_post_notification(const struct cred * w_cred,const struct cred * cred,struct watch_notification * n)4526 int security_post_notification(const struct cred *w_cred,
4527 const struct cred *cred,
4528 struct watch_notification *n)
4529 {
4530 return call_int_hook(post_notification, w_cred, cred, n);
4531 }
4532 #endif /* CONFIG_WATCH_QUEUE */
4533
4534 #ifdef CONFIG_KEY_NOTIFICATIONS
4535 /**
4536 * security_watch_key() - Check if a task is allowed to watch for key events
4537 * @key: the key to watch
4538 *
4539 * Check to see if a process is allowed to watch for event notifications from
4540 * a key or keyring.
4541 *
4542 * Return: Returns 0 if permission is granted.
4543 */
security_watch_key(struct key * key)4544 int security_watch_key(struct key *key)
4545 {
4546 return call_int_hook(watch_key, key);
4547 }
4548 #endif /* CONFIG_KEY_NOTIFICATIONS */
4549
4550 #ifdef CONFIG_SECURITY_NETWORK
4551 /**
4552 * security_netlink_send() - Save info and check if netlink sending is allowed
4553 * @sk: sending socket
4554 * @skb: netlink message
4555 *
4556 * Save security information for a netlink message so that permission checking
4557 * can be performed when the message is processed. The security information
4558 * can be saved using the eff_cap field of the netlink_skb_parms structure.
4559 * Also may be used to provide fine grained control over message transmission.
4560 *
4561 * Return: Returns 0 if the information was successfully saved and message is
4562 * allowed to be transmitted.
4563 */
security_netlink_send(struct sock * sk,struct sk_buff * skb)4564 int security_netlink_send(struct sock *sk, struct sk_buff *skb)
4565 {
4566 return call_int_hook(netlink_send, sk, skb);
4567 }
4568
4569 /**
4570 * security_unix_stream_connect() - Check if a AF_UNIX stream is allowed
4571 * @sock: originating sock
4572 * @other: peer sock
4573 * @newsk: new sock
4574 *
4575 * Check permissions before establishing a Unix domain stream connection
4576 * between @sock and @other.
4577 *
4578 * The @unix_stream_connect and @unix_may_send hooks were necessary because
4579 * Linux provides an alternative to the conventional file name space for Unix
4580 * domain sockets. Whereas binding and connecting to sockets in the file name
4581 * space is mediated by the typical file permissions (and caught by the mknod
4582 * and permission hooks in inode_security_ops), binding and connecting to
4583 * sockets in the abstract name space is completely unmediated. Sufficient
4584 * control of Unix domain sockets in the abstract name space isn't possible
4585 * using only the socket layer hooks, since we need to know the actual target
4586 * socket, which is not looked up until we are inside the af_unix code.
4587 *
4588 * Return: Returns 0 if permission is granted.
4589 */
security_unix_stream_connect(struct sock * sock,struct sock * other,struct sock * newsk)4590 int security_unix_stream_connect(struct sock *sock, struct sock *other,
4591 struct sock *newsk)
4592 {
4593 return call_int_hook(unix_stream_connect, sock, other, newsk);
4594 }
4595 EXPORT_SYMBOL(security_unix_stream_connect);
4596
4597 /**
4598 * security_unix_may_send() - Check if AF_UNIX socket can send datagrams
4599 * @sock: originating sock
4600 * @other: peer sock
4601 *
4602 * Check permissions before connecting or sending datagrams from @sock to
4603 * @other.
4604 *
4605 * The @unix_stream_connect and @unix_may_send hooks were necessary because
4606 * Linux provides an alternative to the conventional file name space for Unix
4607 * domain sockets. Whereas binding and connecting to sockets in the file name
4608 * space is mediated by the typical file permissions (and caught by the mknod
4609 * and permission hooks in inode_security_ops), binding and connecting to
4610 * sockets in the abstract name space is completely unmediated. Sufficient
4611 * control of Unix domain sockets in the abstract name space isn't possible
4612 * using only the socket layer hooks, since we need to know the actual target
4613 * socket, which is not looked up until we are inside the af_unix code.
4614 *
4615 * Return: Returns 0 if permission is granted.
4616 */
security_unix_may_send(struct socket * sock,struct socket * other)4617 int security_unix_may_send(struct socket *sock, struct socket *other)
4618 {
4619 return call_int_hook(unix_may_send, sock, other);
4620 }
4621 EXPORT_SYMBOL(security_unix_may_send);
4622
4623 /**
4624 * security_socket_create() - Check if creating a new socket is allowed
4625 * @family: protocol family
4626 * @type: communications type
4627 * @protocol: requested protocol
4628 * @kern: set to 1 if a kernel socket is requested
4629 *
4630 * Check permissions prior to creating a new socket.
4631 *
4632 * Return: Returns 0 if permission is granted.
4633 */
security_socket_create(int family,int type,int protocol,int kern)4634 int security_socket_create(int family, int type, int protocol, int kern)
4635 {
4636 return call_int_hook(socket_create, family, type, protocol, kern);
4637 }
4638
4639 /**
4640 * security_socket_post_create() - Initialize a newly created socket
4641 * @sock: socket
4642 * @family: protocol family
4643 * @type: communications type
4644 * @protocol: requested protocol
4645 * @kern: set to 1 if a kernel socket is requested
4646 *
4647 * This hook allows a module to update or allocate a per-socket security
4648 * structure. Note that the security field was not added directly to the socket
4649 * structure, but rather, the socket security information is stored in the
4650 * associated inode. Typically, the inode alloc_security hook will allocate
4651 * and attach security information to SOCK_INODE(sock)->i_security. This hook
4652 * may be used to update the SOCK_INODE(sock)->i_security field with additional
4653 * information that wasn't available when the inode was allocated.
4654 *
4655 * Return: Returns 0 if permission is granted.
4656 */
security_socket_post_create(struct socket * sock,int family,int type,int protocol,int kern)4657 int security_socket_post_create(struct socket *sock, int family,
4658 int type, int protocol, int kern)
4659 {
4660 return call_int_hook(socket_post_create, sock, family, type,
4661 protocol, kern);
4662 }
4663
4664 /**
4665 * security_socket_socketpair() - Check if creating a socketpair is allowed
4666 * @socka: first socket
4667 * @sockb: second socket
4668 *
4669 * Check permissions before creating a fresh pair of sockets.
4670 *
4671 * Return: Returns 0 if permission is granted and the connection was
4672 * established.
4673 */
security_socket_socketpair(struct socket * socka,struct socket * sockb)4674 int security_socket_socketpair(struct socket *socka, struct socket *sockb)
4675 {
4676 return call_int_hook(socket_socketpair, socka, sockb);
4677 }
4678 EXPORT_SYMBOL(security_socket_socketpair);
4679
4680 /**
4681 * security_socket_bind() - Check if a socket bind operation is allowed
4682 * @sock: socket
4683 * @address: requested bind address
4684 * @addrlen: length of address
4685 *
4686 * Check permission before socket protocol layer bind operation is performed
4687 * and the socket @sock is bound to the address specified in the @address
4688 * parameter.
4689 *
4690 * Return: Returns 0 if permission is granted.
4691 */
security_socket_bind(struct socket * sock,struct sockaddr * address,int addrlen)4692 int security_socket_bind(struct socket *sock,
4693 struct sockaddr *address, int addrlen)
4694 {
4695 return call_int_hook(socket_bind, sock, address, addrlen);
4696 }
4697
4698 /**
4699 * security_socket_connect() - Check if a socket connect operation is allowed
4700 * @sock: socket
4701 * @address: address of remote connection point
4702 * @addrlen: length of address
4703 *
4704 * Check permission before socket protocol layer connect operation attempts to
4705 * connect socket @sock to a remote address, @address.
4706 *
4707 * Return: Returns 0 if permission is granted.
4708 */
security_socket_connect(struct socket * sock,struct sockaddr * address,int addrlen)4709 int security_socket_connect(struct socket *sock,
4710 struct sockaddr *address, int addrlen)
4711 {
4712 return call_int_hook(socket_connect, sock, address, addrlen);
4713 }
4714
4715 /**
4716 * security_socket_listen() - Check if a socket is allowed to listen
4717 * @sock: socket
4718 * @backlog: connection queue size
4719 *
4720 * Check permission before socket protocol layer listen operation.
4721 *
4722 * Return: Returns 0 if permission is granted.
4723 */
security_socket_listen(struct socket * sock,int backlog)4724 int security_socket_listen(struct socket *sock, int backlog)
4725 {
4726 return call_int_hook(socket_listen, sock, backlog);
4727 }
4728
4729 /**
4730 * security_socket_accept() - Check if a socket is allowed to accept connections
4731 * @sock: listening socket
4732 * @newsock: newly creation connection socket
4733 *
4734 * Check permission before accepting a new connection. Note that the new
4735 * socket, @newsock, has been created and some information copied to it, but
4736 * the accept operation has not actually been performed.
4737 *
4738 * Return: Returns 0 if permission is granted.
4739 */
security_socket_accept(struct socket * sock,struct socket * newsock)4740 int security_socket_accept(struct socket *sock, struct socket *newsock)
4741 {
4742 return call_int_hook(socket_accept, sock, newsock);
4743 }
4744
4745 /**
4746 * security_socket_sendmsg() - Check if sending a message is allowed
4747 * @sock: sending socket
4748 * @msg: message to send
4749 * @size: size of message
4750 *
4751 * Check permission before transmitting a message to another socket.
4752 *
4753 * Return: Returns 0 if permission is granted.
4754 */
security_socket_sendmsg(struct socket * sock,struct msghdr * msg,int size)4755 int security_socket_sendmsg(struct socket *sock, struct msghdr *msg, int size)
4756 {
4757 return call_int_hook(socket_sendmsg, sock, msg, size);
4758 }
4759
4760 /**
4761 * security_socket_recvmsg() - Check if receiving a message is allowed
4762 * @sock: receiving socket
4763 * @msg: message to receive
4764 * @size: size of message
4765 * @flags: operational flags
4766 *
4767 * Check permission before receiving a message from a socket.
4768 *
4769 * Return: Returns 0 if permission is granted.
4770 */
security_socket_recvmsg(struct socket * sock,struct msghdr * msg,int size,int flags)4771 int security_socket_recvmsg(struct socket *sock, struct msghdr *msg,
4772 int size, int flags)
4773 {
4774 return call_int_hook(socket_recvmsg, sock, msg, size, flags);
4775 }
4776
4777 /**
4778 * security_socket_getsockname() - Check if reading the socket addr is allowed
4779 * @sock: socket
4780 *
4781 * Check permission before reading the local address (name) of the socket
4782 * object.
4783 *
4784 * Return: Returns 0 if permission is granted.
4785 */
security_socket_getsockname(struct socket * sock)4786 int security_socket_getsockname(struct socket *sock)
4787 {
4788 return call_int_hook(socket_getsockname, sock);
4789 }
4790
4791 /**
4792 * security_socket_getpeername() - Check if reading the peer's addr is allowed
4793 * @sock: socket
4794 *
4795 * Check permission before the remote address (name) of a socket object.
4796 *
4797 * Return: Returns 0 if permission is granted.
4798 */
security_socket_getpeername(struct socket * sock)4799 int security_socket_getpeername(struct socket *sock)
4800 {
4801 return call_int_hook(socket_getpeername, sock);
4802 }
4803
4804 /**
4805 * security_socket_getsockopt() - Check if reading a socket option is allowed
4806 * @sock: socket
4807 * @level: option's protocol level
4808 * @optname: option name
4809 *
4810 * Check permissions before retrieving the options associated with socket
4811 * @sock.
4812 *
4813 * Return: Returns 0 if permission is granted.
4814 */
security_socket_getsockopt(struct socket * sock,int level,int optname)4815 int security_socket_getsockopt(struct socket *sock, int level, int optname)
4816 {
4817 return call_int_hook(socket_getsockopt, sock, level, optname);
4818 }
4819
4820 /**
4821 * security_socket_setsockopt() - Check if setting a socket option is allowed
4822 * @sock: socket
4823 * @level: option's protocol level
4824 * @optname: option name
4825 *
4826 * Check permissions before setting the options associated with socket @sock.
4827 *
4828 * Return: Returns 0 if permission is granted.
4829 */
security_socket_setsockopt(struct socket * sock,int level,int optname)4830 int security_socket_setsockopt(struct socket *sock, int level, int optname)
4831 {
4832 return call_int_hook(socket_setsockopt, sock, level, optname);
4833 }
4834
4835 /**
4836 * security_socket_shutdown() - Checks if shutting down the socket is allowed
4837 * @sock: socket
4838 * @how: flag indicating how sends and receives are handled
4839 *
4840 * Checks permission before all or part of a connection on the socket @sock is
4841 * shut down.
4842 *
4843 * Return: Returns 0 if permission is granted.
4844 */
security_socket_shutdown(struct socket * sock,int how)4845 int security_socket_shutdown(struct socket *sock, int how)
4846 {
4847 return call_int_hook(socket_shutdown, sock, how);
4848 }
4849
4850 /**
4851 * security_sock_rcv_skb() - Check if an incoming network packet is allowed
4852 * @sk: destination sock
4853 * @skb: incoming packet
4854 *
4855 * Check permissions on incoming network packets. This hook is distinct from
4856 * Netfilter's IP input hooks since it is the first time that the incoming
4857 * sk_buff @skb has been associated with a particular socket, @sk. Must not
4858 * sleep inside this hook because some callers hold spinlocks.
4859 *
4860 * Return: Returns 0 if permission is granted.
4861 */
security_sock_rcv_skb(struct sock * sk,struct sk_buff * skb)4862 int security_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
4863 {
4864 return call_int_hook(socket_sock_rcv_skb, sk, skb);
4865 }
4866 EXPORT_SYMBOL(security_sock_rcv_skb);
4867
4868 /**
4869 * security_socket_getpeersec_stream() - Get the remote peer label
4870 * @sock: socket
4871 * @optval: destination buffer
4872 * @optlen: size of peer label copied into the buffer
4873 * @len: maximum size of the destination buffer
4874 *
4875 * This hook allows the security module to provide peer socket security state
4876 * for unix or connected tcp sockets to userspace via getsockopt SO_GETPEERSEC.
4877 * For tcp sockets this can be meaningful if the socket is associated with an
4878 * ipsec SA.
4879 *
4880 * Return: Returns 0 if all is well, otherwise, typical getsockopt return
4881 * values.
4882 */
security_socket_getpeersec_stream(struct socket * sock,sockptr_t optval,sockptr_t optlen,unsigned int len)4883 int security_socket_getpeersec_stream(struct socket *sock, sockptr_t optval,
4884 sockptr_t optlen, unsigned int len)
4885 {
4886 return call_int_hook(socket_getpeersec_stream, sock, optval, optlen,
4887 len);
4888 }
4889
4890 /**
4891 * security_socket_getpeersec_dgram() - Get the remote peer label
4892 * @sock: socket
4893 * @skb: datagram packet
4894 * @secid: remote peer label secid
4895 *
4896 * This hook allows the security module to provide peer socket security state
4897 * for udp sockets on a per-packet basis to userspace via getsockopt
4898 * SO_GETPEERSEC. The application must first have indicated the IP_PASSSEC
4899 * option via getsockopt. It can then retrieve the security state returned by
4900 * this hook for a packet via the SCM_SECURITY ancillary message type.
4901 *
4902 * Return: Returns 0 on success, error on failure.
4903 */
security_socket_getpeersec_dgram(struct socket * sock,struct sk_buff * skb,u32 * secid)4904 int security_socket_getpeersec_dgram(struct socket *sock,
4905 struct sk_buff *skb, u32 *secid)
4906 {
4907 return call_int_hook(socket_getpeersec_dgram, sock, skb, secid);
4908 }
4909 EXPORT_SYMBOL(security_socket_getpeersec_dgram);
4910
4911 /**
4912 * lsm_sock_alloc - allocate a composite sock blob
4913 * @sock: the sock that needs a blob
4914 * @gfp: allocation mode
4915 *
4916 * Allocate the sock blob for all the modules
4917 *
4918 * Returns 0, or -ENOMEM if memory can't be allocated.
4919 */
lsm_sock_alloc(struct sock * sock,gfp_t gfp)4920 static int lsm_sock_alloc(struct sock *sock, gfp_t gfp)
4921 {
4922 return lsm_blob_alloc(&sock->sk_security, blob_sizes.lbs_sock, gfp);
4923 }
4924
4925 /**
4926 * security_sk_alloc() - Allocate and initialize a sock's LSM blob
4927 * @sk: sock
4928 * @family: protocol family
4929 * @priority: gfp flags
4930 *
4931 * Allocate and attach a security structure to the sk->sk_security field, which
4932 * is used to copy security attributes between local stream sockets.
4933 *
4934 * Return: Returns 0 on success, error on failure.
4935 */
security_sk_alloc(struct sock * sk,int family,gfp_t priority)4936 int security_sk_alloc(struct sock *sk, int family, gfp_t priority)
4937 {
4938 int rc = lsm_sock_alloc(sk, priority);
4939
4940 if (unlikely(rc))
4941 return rc;
4942 rc = call_int_hook(sk_alloc_security, sk, family, priority);
4943 if (unlikely(rc))
4944 security_sk_free(sk);
4945 return rc;
4946 }
4947
4948 /**
4949 * security_sk_free() - Free the sock's LSM blob
4950 * @sk: sock
4951 *
4952 * Deallocate security structure.
4953 */
security_sk_free(struct sock * sk)4954 void security_sk_free(struct sock *sk)
4955 {
4956 call_void_hook(sk_free_security, sk);
4957 kfree(sk->sk_security);
4958 sk->sk_security = NULL;
4959 }
4960
4961 /**
4962 * security_sk_clone() - Clone a sock's LSM state
4963 * @sk: original sock
4964 * @newsk: target sock
4965 *
4966 * Clone/copy security structure.
4967 */
security_sk_clone(const struct sock * sk,struct sock * newsk)4968 void security_sk_clone(const struct sock *sk, struct sock *newsk)
4969 {
4970 call_void_hook(sk_clone_security, sk, newsk);
4971 }
4972 EXPORT_SYMBOL(security_sk_clone);
4973
4974 /**
4975 * security_sk_classify_flow() - Set a flow's secid based on socket
4976 * @sk: original socket
4977 * @flic: target flow
4978 *
4979 * Set the target flow's secid to socket's secid.
4980 */
security_sk_classify_flow(const struct sock * sk,struct flowi_common * flic)4981 void security_sk_classify_flow(const struct sock *sk, struct flowi_common *flic)
4982 {
4983 call_void_hook(sk_getsecid, sk, &flic->flowic_secid);
4984 }
4985 EXPORT_SYMBOL(security_sk_classify_flow);
4986
4987 /**
4988 * security_req_classify_flow() - Set a flow's secid based on request_sock
4989 * @req: request_sock
4990 * @flic: target flow
4991 *
4992 * Sets @flic's secid to @req's secid.
4993 */
security_req_classify_flow(const struct request_sock * req,struct flowi_common * flic)4994 void security_req_classify_flow(const struct request_sock *req,
4995 struct flowi_common *flic)
4996 {
4997 call_void_hook(req_classify_flow, req, flic);
4998 }
4999 EXPORT_SYMBOL(security_req_classify_flow);
5000
5001 /**
5002 * security_sock_graft() - Reconcile LSM state when grafting a sock on a socket
5003 * @sk: sock being grafted
5004 * @parent: target parent socket
5005 *
5006 * Sets @parent's inode secid to @sk's secid and update @sk with any necessary
5007 * LSM state from @parent.
5008 */
security_sock_graft(struct sock * sk,struct socket * parent)5009 void security_sock_graft(struct sock *sk, struct socket *parent)
5010 {
5011 call_void_hook(sock_graft, sk, parent);
5012 }
5013 EXPORT_SYMBOL(security_sock_graft);
5014
5015 /**
5016 * security_inet_conn_request() - Set request_sock state using incoming connect
5017 * @sk: parent listening sock
5018 * @skb: incoming connection
5019 * @req: new request_sock
5020 *
5021 * Initialize the @req LSM state based on @sk and the incoming connect in @skb.
5022 *
5023 * Return: Returns 0 if permission is granted.
5024 */
security_inet_conn_request(const struct sock * sk,struct sk_buff * skb,struct request_sock * req)5025 int security_inet_conn_request(const struct sock *sk,
5026 struct sk_buff *skb, struct request_sock *req)
5027 {
5028 return call_int_hook(inet_conn_request, sk, skb, req);
5029 }
5030 EXPORT_SYMBOL(security_inet_conn_request);
5031
5032 /**
5033 * security_inet_csk_clone() - Set new sock LSM state based on request_sock
5034 * @newsk: new sock
5035 * @req: connection request_sock
5036 *
5037 * Set that LSM state of @sock using the LSM state from @req.
5038 */
security_inet_csk_clone(struct sock * newsk,const struct request_sock * req)5039 void security_inet_csk_clone(struct sock *newsk,
5040 const struct request_sock *req)
5041 {
5042 call_void_hook(inet_csk_clone, newsk, req);
5043 }
5044
5045 /**
5046 * security_inet_conn_established() - Update sock's LSM state with connection
5047 * @sk: sock
5048 * @skb: connection packet
5049 *
5050 * Update @sock's LSM state to represent a new connection from @skb.
5051 */
security_inet_conn_established(struct sock * sk,struct sk_buff * skb)5052 void security_inet_conn_established(struct sock *sk,
5053 struct sk_buff *skb)
5054 {
5055 call_void_hook(inet_conn_established, sk, skb);
5056 }
5057 EXPORT_SYMBOL(security_inet_conn_established);
5058
5059 /**
5060 * security_secmark_relabel_packet() - Check if setting a secmark is allowed
5061 * @secid: new secmark value
5062 *
5063 * Check if the process should be allowed to relabel packets to @secid.
5064 *
5065 * Return: Returns 0 if permission is granted.
5066 */
security_secmark_relabel_packet(u32 secid)5067 int security_secmark_relabel_packet(u32 secid)
5068 {
5069 return call_int_hook(secmark_relabel_packet, secid);
5070 }
5071 EXPORT_SYMBOL(security_secmark_relabel_packet);
5072
5073 /**
5074 * security_secmark_refcount_inc() - Increment the secmark labeling rule count
5075 *
5076 * Tells the LSM to increment the number of secmark labeling rules loaded.
5077 */
security_secmark_refcount_inc(void)5078 void security_secmark_refcount_inc(void)
5079 {
5080 call_void_hook(secmark_refcount_inc);
5081 }
5082 EXPORT_SYMBOL(security_secmark_refcount_inc);
5083
5084 /**
5085 * security_secmark_refcount_dec() - Decrement the secmark labeling rule count
5086 *
5087 * Tells the LSM to decrement the number of secmark labeling rules loaded.
5088 */
security_secmark_refcount_dec(void)5089 void security_secmark_refcount_dec(void)
5090 {
5091 call_void_hook(secmark_refcount_dec);
5092 }
5093 EXPORT_SYMBOL(security_secmark_refcount_dec);
5094
5095 /**
5096 * security_tun_dev_alloc_security() - Allocate a LSM blob for a TUN device
5097 * @security: pointer to the LSM blob
5098 *
5099 * This hook allows a module to allocate a security structure for a TUN device,
5100 * returning the pointer in @security.
5101 *
5102 * Return: Returns a zero on success, negative values on failure.
5103 */
security_tun_dev_alloc_security(void ** security)5104 int security_tun_dev_alloc_security(void **security)
5105 {
5106 int rc;
5107
5108 rc = lsm_blob_alloc(security, blob_sizes.lbs_tun_dev, GFP_KERNEL);
5109 if (rc)
5110 return rc;
5111
5112 rc = call_int_hook(tun_dev_alloc_security, *security);
5113 if (rc) {
5114 kfree(*security);
5115 *security = NULL;
5116 }
5117 return rc;
5118 }
5119 EXPORT_SYMBOL(security_tun_dev_alloc_security);
5120
5121 /**
5122 * security_tun_dev_free_security() - Free a TUN device LSM blob
5123 * @security: LSM blob
5124 *
5125 * This hook allows a module to free the security structure for a TUN device.
5126 */
security_tun_dev_free_security(void * security)5127 void security_tun_dev_free_security(void *security)
5128 {
5129 kfree(security);
5130 }
5131 EXPORT_SYMBOL(security_tun_dev_free_security);
5132
5133 /**
5134 * security_tun_dev_create() - Check if creating a TUN device is allowed
5135 *
5136 * Check permissions prior to creating a new TUN device.
5137 *
5138 * Return: Returns 0 if permission is granted.
5139 */
security_tun_dev_create(void)5140 int security_tun_dev_create(void)
5141 {
5142 return call_int_hook(tun_dev_create);
5143 }
5144 EXPORT_SYMBOL(security_tun_dev_create);
5145
5146 /**
5147 * security_tun_dev_attach_queue() - Check if attaching a TUN queue is allowed
5148 * @security: TUN device LSM blob
5149 *
5150 * Check permissions prior to attaching to a TUN device queue.
5151 *
5152 * Return: Returns 0 if permission is granted.
5153 */
security_tun_dev_attach_queue(void * security)5154 int security_tun_dev_attach_queue(void *security)
5155 {
5156 return call_int_hook(tun_dev_attach_queue, security);
5157 }
5158 EXPORT_SYMBOL(security_tun_dev_attach_queue);
5159
5160 /**
5161 * security_tun_dev_attach() - Update TUN device LSM state on attach
5162 * @sk: associated sock
5163 * @security: TUN device LSM blob
5164 *
5165 * This hook can be used by the module to update any security state associated
5166 * with the TUN device's sock structure.
5167 *
5168 * Return: Returns 0 if permission is granted.
5169 */
security_tun_dev_attach(struct sock * sk,void * security)5170 int security_tun_dev_attach(struct sock *sk, void *security)
5171 {
5172 return call_int_hook(tun_dev_attach, sk, security);
5173 }
5174 EXPORT_SYMBOL(security_tun_dev_attach);
5175
5176 /**
5177 * security_tun_dev_open() - Update TUN device LSM state on open
5178 * @security: TUN device LSM blob
5179 *
5180 * This hook can be used by the module to update any security state associated
5181 * with the TUN device's security structure.
5182 *
5183 * Return: Returns 0 if permission is granted.
5184 */
security_tun_dev_open(void * security)5185 int security_tun_dev_open(void *security)
5186 {
5187 return call_int_hook(tun_dev_open, security);
5188 }
5189 EXPORT_SYMBOL(security_tun_dev_open);
5190
5191 /**
5192 * security_sctp_assoc_request() - Update the LSM on a SCTP association req
5193 * @asoc: SCTP association
5194 * @skb: packet requesting the association
5195 *
5196 * Passes the @asoc and @chunk->skb of the association INIT packet to the LSM.
5197 *
5198 * Return: Returns 0 on success, error on failure.
5199 */
security_sctp_assoc_request(struct sctp_association * asoc,struct sk_buff * skb)5200 int security_sctp_assoc_request(struct sctp_association *asoc,
5201 struct sk_buff *skb)
5202 {
5203 return call_int_hook(sctp_assoc_request, asoc, skb);
5204 }
5205 EXPORT_SYMBOL(security_sctp_assoc_request);
5206
5207 /**
5208 * security_sctp_bind_connect() - Validate a list of addrs for a SCTP option
5209 * @sk: socket
5210 * @optname: SCTP option to validate
5211 * @address: list of IP addresses to validate
5212 * @addrlen: length of the address list
5213 *
5214 * Validiate permissions required for each address associated with sock @sk.
5215 * Depending on @optname, the addresses will be treated as either a connect or
5216 * bind service. The @addrlen is calculated on each IPv4 and IPv6 address using
5217 * sizeof(struct sockaddr_in) or sizeof(struct sockaddr_in6).
5218 *
5219 * Return: Returns 0 on success, error on failure.
5220 */
security_sctp_bind_connect(struct sock * sk,int optname,struct sockaddr * address,int addrlen)5221 int security_sctp_bind_connect(struct sock *sk, int optname,
5222 struct sockaddr *address, int addrlen)
5223 {
5224 return call_int_hook(sctp_bind_connect, sk, optname, address, addrlen);
5225 }
5226 EXPORT_SYMBOL(security_sctp_bind_connect);
5227
5228 /**
5229 * security_sctp_sk_clone() - Clone a SCTP sock's LSM state
5230 * @asoc: SCTP association
5231 * @sk: original sock
5232 * @newsk: target sock
5233 *
5234 * Called whenever a new socket is created by accept(2) (i.e. a TCP style
5235 * socket) or when a socket is 'peeled off' e.g userspace calls
5236 * sctp_peeloff(3).
5237 */
security_sctp_sk_clone(struct sctp_association * asoc,struct sock * sk,struct sock * newsk)5238 void security_sctp_sk_clone(struct sctp_association *asoc, struct sock *sk,
5239 struct sock *newsk)
5240 {
5241 call_void_hook(sctp_sk_clone, asoc, sk, newsk);
5242 }
5243 EXPORT_SYMBOL(security_sctp_sk_clone);
5244
5245 /**
5246 * security_sctp_assoc_established() - Update LSM state when assoc established
5247 * @asoc: SCTP association
5248 * @skb: packet establishing the association
5249 *
5250 * Passes the @asoc and @chunk->skb of the association COOKIE_ACK packet to the
5251 * security module.
5252 *
5253 * Return: Returns 0 if permission is granted.
5254 */
security_sctp_assoc_established(struct sctp_association * asoc,struct sk_buff * skb)5255 int security_sctp_assoc_established(struct sctp_association *asoc,
5256 struct sk_buff *skb)
5257 {
5258 return call_int_hook(sctp_assoc_established, asoc, skb);
5259 }
5260 EXPORT_SYMBOL(security_sctp_assoc_established);
5261
5262 /**
5263 * security_mptcp_add_subflow() - Inherit the LSM label from the MPTCP socket
5264 * @sk: the owning MPTCP socket
5265 * @ssk: the new subflow
5266 *
5267 * Update the labeling for the given MPTCP subflow, to match the one of the
5268 * owning MPTCP socket. This hook has to be called after the socket creation and
5269 * initialization via the security_socket_create() and
5270 * security_socket_post_create() LSM hooks.
5271 *
5272 * Return: Returns 0 on success or a negative error code on failure.
5273 */
security_mptcp_add_subflow(struct sock * sk,struct sock * ssk)5274 int security_mptcp_add_subflow(struct sock *sk, struct sock *ssk)
5275 {
5276 return call_int_hook(mptcp_add_subflow, sk, ssk);
5277 }
5278
5279 #endif /* CONFIG_SECURITY_NETWORK */
5280
5281 #ifdef CONFIG_SECURITY_INFINIBAND
5282 /**
5283 * security_ib_pkey_access() - Check if access to an IB pkey is allowed
5284 * @sec: LSM blob
5285 * @subnet_prefix: subnet prefix of the port
5286 * @pkey: IB pkey
5287 *
5288 * Check permission to access a pkey when modifying a QP.
5289 *
5290 * Return: Returns 0 if permission is granted.
5291 */
security_ib_pkey_access(void * sec,u64 subnet_prefix,u16 pkey)5292 int security_ib_pkey_access(void *sec, u64 subnet_prefix, u16 pkey)
5293 {
5294 return call_int_hook(ib_pkey_access, sec, subnet_prefix, pkey);
5295 }
5296 EXPORT_SYMBOL(security_ib_pkey_access);
5297
5298 /**
5299 * security_ib_endport_manage_subnet() - Check if SMPs traffic is allowed
5300 * @sec: LSM blob
5301 * @dev_name: IB device name
5302 * @port_num: port number
5303 *
5304 * Check permissions to send and receive SMPs on a end port.
5305 *
5306 * Return: Returns 0 if permission is granted.
5307 */
security_ib_endport_manage_subnet(void * sec,const char * dev_name,u8 port_num)5308 int security_ib_endport_manage_subnet(void *sec,
5309 const char *dev_name, u8 port_num)
5310 {
5311 return call_int_hook(ib_endport_manage_subnet, sec, dev_name, port_num);
5312 }
5313 EXPORT_SYMBOL(security_ib_endport_manage_subnet);
5314
5315 /**
5316 * security_ib_alloc_security() - Allocate an Infiniband LSM blob
5317 * @sec: LSM blob
5318 *
5319 * Allocate a security structure for Infiniband objects.
5320 *
5321 * Return: Returns 0 on success, non-zero on failure.
5322 */
security_ib_alloc_security(void ** sec)5323 int security_ib_alloc_security(void **sec)
5324 {
5325 int rc;
5326
5327 rc = lsm_blob_alloc(sec, blob_sizes.lbs_ib, GFP_KERNEL);
5328 if (rc)
5329 return rc;
5330
5331 rc = call_int_hook(ib_alloc_security, *sec);
5332 if (rc) {
5333 kfree(*sec);
5334 *sec = NULL;
5335 }
5336 return rc;
5337 }
5338 EXPORT_SYMBOL(security_ib_alloc_security);
5339
5340 /**
5341 * security_ib_free_security() - Free an Infiniband LSM blob
5342 * @sec: LSM blob
5343 *
5344 * Deallocate an Infiniband security structure.
5345 */
security_ib_free_security(void * sec)5346 void security_ib_free_security(void *sec)
5347 {
5348 kfree(sec);
5349 }
5350 EXPORT_SYMBOL(security_ib_free_security);
5351 #endif /* CONFIG_SECURITY_INFINIBAND */
5352
5353 #ifdef CONFIG_SECURITY_NETWORK_XFRM
5354 /**
5355 * security_xfrm_policy_alloc() - Allocate a xfrm policy LSM blob
5356 * @ctxp: xfrm security context being added to the SPD
5357 * @sec_ctx: security label provided by userspace
5358 * @gfp: gfp flags
5359 *
5360 * Allocate a security structure to the xp->security field; the security field
5361 * is initialized to NULL when the xfrm_policy is allocated.
5362 *
5363 * Return: Return 0 if operation was successful.
5364 */
security_xfrm_policy_alloc(struct xfrm_sec_ctx ** ctxp,struct xfrm_user_sec_ctx * sec_ctx,gfp_t gfp)5365 int security_xfrm_policy_alloc(struct xfrm_sec_ctx **ctxp,
5366 struct xfrm_user_sec_ctx *sec_ctx,
5367 gfp_t gfp)
5368 {
5369 return call_int_hook(xfrm_policy_alloc_security, ctxp, sec_ctx, gfp);
5370 }
5371 EXPORT_SYMBOL(security_xfrm_policy_alloc);
5372
5373 /**
5374 * security_xfrm_policy_clone() - Clone xfrm policy LSM state
5375 * @old_ctx: xfrm security context
5376 * @new_ctxp: target xfrm security context
5377 *
5378 * Allocate a security structure in new_ctxp that contains the information from
5379 * the old_ctx structure.
5380 *
5381 * Return: Return 0 if operation was successful.
5382 */
security_xfrm_policy_clone(struct xfrm_sec_ctx * old_ctx,struct xfrm_sec_ctx ** new_ctxp)5383 int security_xfrm_policy_clone(struct xfrm_sec_ctx *old_ctx,
5384 struct xfrm_sec_ctx **new_ctxp)
5385 {
5386 return call_int_hook(xfrm_policy_clone_security, old_ctx, new_ctxp);
5387 }
5388
5389 /**
5390 * security_xfrm_policy_free() - Free a xfrm security context
5391 * @ctx: xfrm security context
5392 *
5393 * Free LSM resources associated with @ctx.
5394 */
security_xfrm_policy_free(struct xfrm_sec_ctx * ctx)5395 void security_xfrm_policy_free(struct xfrm_sec_ctx *ctx)
5396 {
5397 call_void_hook(xfrm_policy_free_security, ctx);
5398 }
5399 EXPORT_SYMBOL(security_xfrm_policy_free);
5400
5401 /**
5402 * security_xfrm_policy_delete() - Check if deleting a xfrm policy is allowed
5403 * @ctx: xfrm security context
5404 *
5405 * Authorize deletion of a SPD entry.
5406 *
5407 * Return: Returns 0 if permission is granted.
5408 */
security_xfrm_policy_delete(struct xfrm_sec_ctx * ctx)5409 int security_xfrm_policy_delete(struct xfrm_sec_ctx *ctx)
5410 {
5411 return call_int_hook(xfrm_policy_delete_security, ctx);
5412 }
5413
5414 /**
5415 * security_xfrm_state_alloc() - Allocate a xfrm state LSM blob
5416 * @x: xfrm state being added to the SAD
5417 * @sec_ctx: security label provided by userspace
5418 *
5419 * Allocate a security structure to the @x->security field; the security field
5420 * is initialized to NULL when the xfrm_state is allocated. Set the context to
5421 * correspond to @sec_ctx.
5422 *
5423 * Return: Return 0 if operation was successful.
5424 */
security_xfrm_state_alloc(struct xfrm_state * x,struct xfrm_user_sec_ctx * sec_ctx)5425 int security_xfrm_state_alloc(struct xfrm_state *x,
5426 struct xfrm_user_sec_ctx *sec_ctx)
5427 {
5428 return call_int_hook(xfrm_state_alloc, x, sec_ctx);
5429 }
5430 EXPORT_SYMBOL(security_xfrm_state_alloc);
5431
5432 /**
5433 * security_xfrm_state_alloc_acquire() - Allocate a xfrm state LSM blob
5434 * @x: xfrm state being added to the SAD
5435 * @polsec: associated policy's security context
5436 * @secid: secid from the flow
5437 *
5438 * Allocate a security structure to the x->security field; the security field
5439 * is initialized to NULL when the xfrm_state is allocated. Set the context to
5440 * correspond to secid.
5441 *
5442 * Return: Returns 0 if operation was successful.
5443 */
security_xfrm_state_alloc_acquire(struct xfrm_state * x,struct xfrm_sec_ctx * polsec,u32 secid)5444 int security_xfrm_state_alloc_acquire(struct xfrm_state *x,
5445 struct xfrm_sec_ctx *polsec, u32 secid)
5446 {
5447 return call_int_hook(xfrm_state_alloc_acquire, x, polsec, secid);
5448 }
5449
5450 /**
5451 * security_xfrm_state_delete() - Check if deleting a xfrm state is allowed
5452 * @x: xfrm state
5453 *
5454 * Authorize deletion of x->security.
5455 *
5456 * Return: Returns 0 if permission is granted.
5457 */
security_xfrm_state_delete(struct xfrm_state * x)5458 int security_xfrm_state_delete(struct xfrm_state *x)
5459 {
5460 return call_int_hook(xfrm_state_delete_security, x);
5461 }
5462 EXPORT_SYMBOL(security_xfrm_state_delete);
5463
5464 /**
5465 * security_xfrm_state_free() - Free a xfrm state
5466 * @x: xfrm state
5467 *
5468 * Deallocate x->security.
5469 */
security_xfrm_state_free(struct xfrm_state * x)5470 void security_xfrm_state_free(struct xfrm_state *x)
5471 {
5472 call_void_hook(xfrm_state_free_security, x);
5473 }
5474
5475 /**
5476 * security_xfrm_policy_lookup() - Check if using a xfrm policy is allowed
5477 * @ctx: target xfrm security context
5478 * @fl_secid: flow secid used to authorize access
5479 *
5480 * Check permission when a flow selects a xfrm_policy for processing XFRMs on a
5481 * packet. The hook is called when selecting either a per-socket policy or a
5482 * generic xfrm policy.
5483 *
5484 * Return: Return 0 if permission is granted, -ESRCH otherwise, or -errno on
5485 * other errors.
5486 */
security_xfrm_policy_lookup(struct xfrm_sec_ctx * ctx,u32 fl_secid)5487 int security_xfrm_policy_lookup(struct xfrm_sec_ctx *ctx, u32 fl_secid)
5488 {
5489 return call_int_hook(xfrm_policy_lookup, ctx, fl_secid);
5490 }
5491
5492 /**
5493 * security_xfrm_state_pol_flow_match() - Check for a xfrm match
5494 * @x: xfrm state to match
5495 * @xp: xfrm policy to check for a match
5496 * @flic: flow to check for a match.
5497 *
5498 * Check @xp and @flic for a match with @x.
5499 *
5500 * Return: Returns 1 if there is a match.
5501 */
security_xfrm_state_pol_flow_match(struct xfrm_state * x,struct xfrm_policy * xp,const struct flowi_common * flic)5502 int security_xfrm_state_pol_flow_match(struct xfrm_state *x,
5503 struct xfrm_policy *xp,
5504 const struct flowi_common *flic)
5505 {
5506 struct lsm_static_call *scall;
5507 int rc = LSM_RET_DEFAULT(xfrm_state_pol_flow_match);
5508
5509 /*
5510 * Since this function is expected to return 0 or 1, the judgment
5511 * becomes difficult if multiple LSMs supply this call. Fortunately,
5512 * we can use the first LSM's judgment because currently only SELinux
5513 * supplies this call.
5514 *
5515 * For speed optimization, we explicitly break the loop rather than
5516 * using the macro
5517 */
5518 lsm_for_each_hook(scall, xfrm_state_pol_flow_match) {
5519 rc = scall->hl->hook.xfrm_state_pol_flow_match(x, xp, flic);
5520 break;
5521 }
5522 return rc;
5523 }
5524
5525 /**
5526 * security_xfrm_decode_session() - Determine the xfrm secid for a packet
5527 * @skb: xfrm packet
5528 * @secid: secid
5529 *
5530 * Decode the packet in @skb and return the security label in @secid.
5531 *
5532 * Return: Return 0 if all xfrms used have the same secid.
5533 */
security_xfrm_decode_session(struct sk_buff * skb,u32 * secid)5534 int security_xfrm_decode_session(struct sk_buff *skb, u32 *secid)
5535 {
5536 return call_int_hook(xfrm_decode_session, skb, secid, 1);
5537 }
5538
security_skb_classify_flow(struct sk_buff * skb,struct flowi_common * flic)5539 void security_skb_classify_flow(struct sk_buff *skb, struct flowi_common *flic)
5540 {
5541 int rc = call_int_hook(xfrm_decode_session, skb, &flic->flowic_secid,
5542 0);
5543
5544 BUG_ON(rc);
5545 }
5546 EXPORT_SYMBOL(security_skb_classify_flow);
5547 #endif /* CONFIG_SECURITY_NETWORK_XFRM */
5548
5549 #ifdef CONFIG_KEYS
5550 /**
5551 * security_key_alloc() - Allocate and initialize a kernel key LSM blob
5552 * @key: key
5553 * @cred: credentials
5554 * @flags: allocation flags
5555 *
5556 * Permit allocation of a key and assign security data. Note that key does not
5557 * have a serial number assigned at this point.
5558 *
5559 * Return: Return 0 if permission is granted, -ve error otherwise.
5560 */
security_key_alloc(struct key * key,const struct cred * cred,unsigned long flags)5561 int security_key_alloc(struct key *key, const struct cred *cred,
5562 unsigned long flags)
5563 {
5564 int rc = lsm_key_alloc(key);
5565
5566 if (unlikely(rc))
5567 return rc;
5568 rc = call_int_hook(key_alloc, key, cred, flags);
5569 if (unlikely(rc))
5570 security_key_free(key);
5571 return rc;
5572 }
5573
5574 /**
5575 * security_key_free() - Free a kernel key LSM blob
5576 * @key: key
5577 *
5578 * Notification of destruction; free security data.
5579 */
security_key_free(struct key * key)5580 void security_key_free(struct key *key)
5581 {
5582 kfree(key->security);
5583 key->security = NULL;
5584 }
5585
5586 /**
5587 * security_key_permission() - Check if a kernel key operation is allowed
5588 * @key_ref: key reference
5589 * @cred: credentials of actor requesting access
5590 * @need_perm: requested permissions
5591 *
5592 * See whether a specific operational right is granted to a process on a key.
5593 *
5594 * Return: Return 0 if permission is granted, -ve error otherwise.
5595 */
security_key_permission(key_ref_t key_ref,const struct cred * cred,enum key_need_perm need_perm)5596 int security_key_permission(key_ref_t key_ref, const struct cred *cred,
5597 enum key_need_perm need_perm)
5598 {
5599 return call_int_hook(key_permission, key_ref, cred, need_perm);
5600 }
5601
5602 /**
5603 * security_key_getsecurity() - Get the key's security label
5604 * @key: key
5605 * @buffer: security label buffer
5606 *
5607 * Get a textual representation of the security context attached to a key for
5608 * the purposes of honouring KEYCTL_GETSECURITY. This function allocates the
5609 * storage for the NUL-terminated string and the caller should free it.
5610 *
5611 * Return: Returns the length of @buffer (including terminating NUL) or -ve if
5612 * an error occurs. May also return 0 (and a NULL buffer pointer) if
5613 * there is no security label assigned to the key.
5614 */
security_key_getsecurity(struct key * key,char ** buffer)5615 int security_key_getsecurity(struct key *key, char **buffer)
5616 {
5617 *buffer = NULL;
5618 return call_int_hook(key_getsecurity, key, buffer);
5619 }
5620
5621 /**
5622 * security_key_post_create_or_update() - Notification of key create or update
5623 * @keyring: keyring to which the key is linked to
5624 * @key: created or updated key
5625 * @payload: data used to instantiate or update the key
5626 * @payload_len: length of payload
5627 * @flags: key flags
5628 * @create: flag indicating whether the key was created or updated
5629 *
5630 * Notify the caller of a key creation or update.
5631 */
security_key_post_create_or_update(struct key * keyring,struct key * key,const void * payload,size_t payload_len,unsigned long flags,bool create)5632 void security_key_post_create_or_update(struct key *keyring, struct key *key,
5633 const void *payload, size_t payload_len,
5634 unsigned long flags, bool create)
5635 {
5636 call_void_hook(key_post_create_or_update, keyring, key, payload,
5637 payload_len, flags, create);
5638 }
5639 #endif /* CONFIG_KEYS */
5640
5641 #ifdef CONFIG_AUDIT
5642 /**
5643 * security_audit_rule_init() - Allocate and init an LSM audit rule struct
5644 * @field: audit action
5645 * @op: rule operator
5646 * @rulestr: rule context
5647 * @lsmrule: receive buffer for audit rule struct
5648 * @gfp: GFP flag used for kmalloc
5649 *
5650 * Allocate and initialize an LSM audit rule structure.
5651 *
5652 * Return: Return 0 if @lsmrule has been successfully set, -EINVAL in case of
5653 * an invalid rule.
5654 */
security_audit_rule_init(u32 field,u32 op,char * rulestr,void ** lsmrule,gfp_t gfp)5655 int security_audit_rule_init(u32 field, u32 op, char *rulestr, void **lsmrule,
5656 gfp_t gfp)
5657 {
5658 return call_int_hook(audit_rule_init, field, op, rulestr, lsmrule, gfp);
5659 }
5660
5661 /**
5662 * security_audit_rule_known() - Check if an audit rule contains LSM fields
5663 * @krule: audit rule
5664 *
5665 * Specifies whether given @krule contains any fields related to the current
5666 * LSM.
5667 *
5668 * Return: Returns 1 in case of relation found, 0 otherwise.
5669 */
security_audit_rule_known(struct audit_krule * krule)5670 int security_audit_rule_known(struct audit_krule *krule)
5671 {
5672 return call_int_hook(audit_rule_known, krule);
5673 }
5674
5675 /**
5676 * security_audit_rule_free() - Free an LSM audit rule struct
5677 * @lsmrule: audit rule struct
5678 *
5679 * Deallocate the LSM audit rule structure previously allocated by
5680 * audit_rule_init().
5681 */
security_audit_rule_free(void * lsmrule)5682 void security_audit_rule_free(void *lsmrule)
5683 {
5684 call_void_hook(audit_rule_free, lsmrule);
5685 }
5686
5687 /**
5688 * security_audit_rule_match() - Check if a label matches an audit rule
5689 * @prop: security label
5690 * @field: LSM audit field
5691 * @op: matching operator
5692 * @lsmrule: audit rule
5693 *
5694 * Determine if given @secid matches a rule previously approved by
5695 * security_audit_rule_known().
5696 *
5697 * Return: Returns 1 if secid matches the rule, 0 if it does not, -ERRNO on
5698 * failure.
5699 */
security_audit_rule_match(struct lsm_prop * prop,u32 field,u32 op,void * lsmrule)5700 int security_audit_rule_match(struct lsm_prop *prop, u32 field, u32 op,
5701 void *lsmrule)
5702 {
5703 return call_int_hook(audit_rule_match, prop, field, op, lsmrule);
5704 }
5705 #endif /* CONFIG_AUDIT */
5706
5707 #ifdef CONFIG_BPF_SYSCALL
5708 /**
5709 * security_bpf() - Check if the bpf syscall operation is allowed
5710 * @cmd: command
5711 * @attr: bpf attribute
5712 * @size: size
5713 * @kernel: whether or not call originated from kernel
5714 *
5715 * Do a initial check for all bpf syscalls after the attribute is copied into
5716 * the kernel. The actual security module can implement their own rules to
5717 * check the specific cmd they need.
5718 *
5719 * Return: Returns 0 if permission is granted.
5720 */
security_bpf(int cmd,union bpf_attr * attr,unsigned int size,bool kernel)5721 int security_bpf(int cmd, union bpf_attr *attr, unsigned int size, bool kernel)
5722 {
5723 return call_int_hook(bpf, cmd, attr, size, kernel);
5724 }
5725
5726 /**
5727 * security_bpf_map() - Check if access to a bpf map is allowed
5728 * @map: bpf map
5729 * @fmode: mode
5730 *
5731 * Do a check when the kernel generates and returns a file descriptor for eBPF
5732 * maps.
5733 *
5734 * Return: Returns 0 if permission is granted.
5735 */
security_bpf_map(struct bpf_map * map,fmode_t fmode)5736 int security_bpf_map(struct bpf_map *map, fmode_t fmode)
5737 {
5738 return call_int_hook(bpf_map, map, fmode);
5739 }
5740
5741 /**
5742 * security_bpf_prog() - Check if access to a bpf program is allowed
5743 * @prog: bpf program
5744 *
5745 * Do a check when the kernel generates and returns a file descriptor for eBPF
5746 * programs.
5747 *
5748 * Return: Returns 0 if permission is granted.
5749 */
security_bpf_prog(struct bpf_prog * prog)5750 int security_bpf_prog(struct bpf_prog *prog)
5751 {
5752 return call_int_hook(bpf_prog, prog);
5753 }
5754
5755 /**
5756 * security_bpf_map_create() - Check if BPF map creation is allowed
5757 * @map: BPF map object
5758 * @attr: BPF syscall attributes used to create BPF map
5759 * @token: BPF token used to grant user access
5760 * @kernel: whether or not call originated from kernel
5761 *
5762 * Do a check when the kernel creates a new BPF map. This is also the
5763 * point where LSM blob is allocated for LSMs that need them.
5764 *
5765 * Return: Returns 0 on success, error on failure.
5766 */
security_bpf_map_create(struct bpf_map * map,union bpf_attr * attr,struct bpf_token * token,bool kernel)5767 int security_bpf_map_create(struct bpf_map *map, union bpf_attr *attr,
5768 struct bpf_token *token, bool kernel)
5769 {
5770 int rc;
5771
5772 rc = lsm_bpf_map_alloc(map);
5773 if (unlikely(rc))
5774 return rc;
5775
5776 rc = call_int_hook(bpf_map_create, map, attr, token, kernel);
5777 if (unlikely(rc))
5778 security_bpf_map_free(map);
5779 return rc;
5780 }
5781
5782 /**
5783 * security_bpf_prog_load() - Check if loading of BPF program is allowed
5784 * @prog: BPF program object
5785 * @attr: BPF syscall attributes used to create BPF program
5786 * @token: BPF token used to grant user access to BPF subsystem
5787 * @kernel: whether or not call originated from kernel
5788 *
5789 * Perform an access control check when the kernel loads a BPF program and
5790 * allocates associated BPF program object. This hook is also responsible for
5791 * allocating any required LSM state for the BPF program.
5792 *
5793 * Return: Returns 0 on success, error on failure.
5794 */
security_bpf_prog_load(struct bpf_prog * prog,union bpf_attr * attr,struct bpf_token * token,bool kernel)5795 int security_bpf_prog_load(struct bpf_prog *prog, union bpf_attr *attr,
5796 struct bpf_token *token, bool kernel)
5797 {
5798 int rc;
5799
5800 rc = lsm_bpf_prog_alloc(prog);
5801 if (unlikely(rc))
5802 return rc;
5803
5804 rc = call_int_hook(bpf_prog_load, prog, attr, token, kernel);
5805 if (unlikely(rc))
5806 security_bpf_prog_free(prog);
5807 return rc;
5808 }
5809
5810 /**
5811 * security_bpf_token_create() - Check if creating of BPF token is allowed
5812 * @token: BPF token object
5813 * @attr: BPF syscall attributes used to create BPF token
5814 * @path: path pointing to BPF FS mount point from which BPF token is created
5815 *
5816 * Do a check when the kernel instantiates a new BPF token object from BPF FS
5817 * instance. This is also the point where LSM blob can be allocated for LSMs.
5818 *
5819 * Return: Returns 0 on success, error on failure.
5820 */
security_bpf_token_create(struct bpf_token * token,union bpf_attr * attr,const struct path * path)5821 int security_bpf_token_create(struct bpf_token *token, union bpf_attr *attr,
5822 const struct path *path)
5823 {
5824 int rc;
5825
5826 rc = lsm_bpf_token_alloc(token);
5827 if (unlikely(rc))
5828 return rc;
5829
5830 rc = call_int_hook(bpf_token_create, token, attr, path);
5831 if (unlikely(rc))
5832 security_bpf_token_free(token);
5833 return rc;
5834 }
5835
5836 /**
5837 * security_bpf_token_cmd() - Check if BPF token is allowed to delegate
5838 * requested BPF syscall command
5839 * @token: BPF token object
5840 * @cmd: BPF syscall command requested to be delegated by BPF token
5841 *
5842 * Do a check when the kernel decides whether provided BPF token should allow
5843 * delegation of requested BPF syscall command.
5844 *
5845 * Return: Returns 0 on success, error on failure.
5846 */
security_bpf_token_cmd(const struct bpf_token * token,enum bpf_cmd cmd)5847 int security_bpf_token_cmd(const struct bpf_token *token, enum bpf_cmd cmd)
5848 {
5849 return call_int_hook(bpf_token_cmd, token, cmd);
5850 }
5851
5852 /**
5853 * security_bpf_token_capable() - Check if BPF token is allowed to delegate
5854 * requested BPF-related capability
5855 * @token: BPF token object
5856 * @cap: capabilities requested to be delegated by BPF token
5857 *
5858 * Do a check when the kernel decides whether provided BPF token should allow
5859 * delegation of requested BPF-related capabilities.
5860 *
5861 * Return: Returns 0 on success, error on failure.
5862 */
security_bpf_token_capable(const struct bpf_token * token,int cap)5863 int security_bpf_token_capable(const struct bpf_token *token, int cap)
5864 {
5865 return call_int_hook(bpf_token_capable, token, cap);
5866 }
5867
5868 /**
5869 * security_bpf_map_free() - Free a bpf map's LSM blob
5870 * @map: bpf map
5871 *
5872 * Clean up the security information stored inside bpf map.
5873 */
security_bpf_map_free(struct bpf_map * map)5874 void security_bpf_map_free(struct bpf_map *map)
5875 {
5876 call_void_hook(bpf_map_free, map);
5877 kfree(map->security);
5878 map->security = NULL;
5879 }
5880
5881 /**
5882 * security_bpf_prog_free() - Free a BPF program's LSM blob
5883 * @prog: BPF program struct
5884 *
5885 * Clean up the security information stored inside BPF program.
5886 */
security_bpf_prog_free(struct bpf_prog * prog)5887 void security_bpf_prog_free(struct bpf_prog *prog)
5888 {
5889 call_void_hook(bpf_prog_free, prog);
5890 kfree(prog->aux->security);
5891 prog->aux->security = NULL;
5892 }
5893
5894 /**
5895 * security_bpf_token_free() - Free a BPF token's LSM blob
5896 * @token: BPF token struct
5897 *
5898 * Clean up the security information stored inside BPF token.
5899 */
security_bpf_token_free(struct bpf_token * token)5900 void security_bpf_token_free(struct bpf_token *token)
5901 {
5902 call_void_hook(bpf_token_free, token);
5903 kfree(token->security);
5904 token->security = NULL;
5905 }
5906 #endif /* CONFIG_BPF_SYSCALL */
5907
5908 /**
5909 * security_locked_down() - Check if a kernel feature is allowed
5910 * @what: requested kernel feature
5911 *
5912 * Determine whether a kernel feature that potentially enables arbitrary code
5913 * execution in kernel space should be permitted.
5914 *
5915 * Return: Returns 0 if permission is granted.
5916 */
security_locked_down(enum lockdown_reason what)5917 int security_locked_down(enum lockdown_reason what)
5918 {
5919 return call_int_hook(locked_down, what);
5920 }
5921 EXPORT_SYMBOL(security_locked_down);
5922
5923 /**
5924 * security_bdev_alloc() - Allocate a block device LSM blob
5925 * @bdev: block device
5926 *
5927 * Allocate and attach a security structure to @bdev->bd_security. The
5928 * security field is initialized to NULL when the bdev structure is
5929 * allocated.
5930 *
5931 * Return: Return 0 if operation was successful.
5932 */
security_bdev_alloc(struct block_device * bdev)5933 int security_bdev_alloc(struct block_device *bdev)
5934 {
5935 int rc = 0;
5936
5937 rc = lsm_bdev_alloc(bdev);
5938 if (unlikely(rc))
5939 return rc;
5940
5941 rc = call_int_hook(bdev_alloc_security, bdev);
5942 if (unlikely(rc))
5943 security_bdev_free(bdev);
5944
5945 return rc;
5946 }
5947 EXPORT_SYMBOL(security_bdev_alloc);
5948
5949 /**
5950 * security_bdev_free() - Free a block device's LSM blob
5951 * @bdev: block device
5952 *
5953 * Deallocate the bdev security structure and set @bdev->bd_security to NULL.
5954 */
security_bdev_free(struct block_device * bdev)5955 void security_bdev_free(struct block_device *bdev)
5956 {
5957 if (!bdev->bd_security)
5958 return;
5959
5960 call_void_hook(bdev_free_security, bdev);
5961
5962 kfree(bdev->bd_security);
5963 bdev->bd_security = NULL;
5964 }
5965 EXPORT_SYMBOL(security_bdev_free);
5966
5967 /**
5968 * security_bdev_setintegrity() - Set the device's integrity data
5969 * @bdev: block device
5970 * @type: type of integrity, e.g. hash digest, signature, etc
5971 * @value: the integrity value
5972 * @size: size of the integrity value
5973 *
5974 * Register a verified integrity measurement of a bdev with LSMs.
5975 * LSMs should free the previously saved data if @value is NULL.
5976 * Please note that the new hook should be invoked every time the security
5977 * information is updated to keep these data current. For example, in dm-verity,
5978 * if the mapping table is reloaded and configured to use a different dm-verity
5979 * target with a new roothash and signing information, the previously stored
5980 * data in the LSM blob will become obsolete. It is crucial to re-invoke the
5981 * hook to refresh these data and ensure they are up to date. This necessity
5982 * arises from the design of device-mapper, where a device-mapper device is
5983 * first created, and then targets are subsequently loaded into it. These
5984 * targets can be modified multiple times during the device's lifetime.
5985 * Therefore, while the LSM blob is allocated during the creation of the block
5986 * device, its actual contents are not initialized at this stage and can change
5987 * substantially over time. This includes alterations from data that the LSMs
5988 * 'trusts' to those they do not, making it essential to handle these changes
5989 * correctly. Failure to address this dynamic aspect could potentially allow
5990 * for bypassing LSM checks.
5991 *
5992 * Return: Returns 0 on success, negative values on failure.
5993 */
security_bdev_setintegrity(struct block_device * bdev,enum lsm_integrity_type type,const void * value,size_t size)5994 int security_bdev_setintegrity(struct block_device *bdev,
5995 enum lsm_integrity_type type, const void *value,
5996 size_t size)
5997 {
5998 return call_int_hook(bdev_setintegrity, bdev, type, value, size);
5999 }
6000 EXPORT_SYMBOL(security_bdev_setintegrity);
6001
6002 #ifdef CONFIG_PERF_EVENTS
6003 /**
6004 * security_perf_event_open() - Check if a perf event open is allowed
6005 * @type: type of event
6006 *
6007 * Check whether the @type of perf_event_open syscall is allowed.
6008 *
6009 * Return: Returns 0 if permission is granted.
6010 */
security_perf_event_open(int type)6011 int security_perf_event_open(int type)
6012 {
6013 return call_int_hook(perf_event_open, type);
6014 }
6015
6016 /**
6017 * security_perf_event_alloc() - Allocate a perf event LSM blob
6018 * @event: perf event
6019 *
6020 * Allocate and save perf_event security info.
6021 *
6022 * Return: Returns 0 on success, error on failure.
6023 */
security_perf_event_alloc(struct perf_event * event)6024 int security_perf_event_alloc(struct perf_event *event)
6025 {
6026 int rc;
6027
6028 rc = lsm_blob_alloc(&event->security, blob_sizes.lbs_perf_event,
6029 GFP_KERNEL);
6030 if (rc)
6031 return rc;
6032
6033 rc = call_int_hook(perf_event_alloc, event);
6034 if (rc) {
6035 kfree(event->security);
6036 event->security = NULL;
6037 }
6038 return rc;
6039 }
6040
6041 /**
6042 * security_perf_event_free() - Free a perf event LSM blob
6043 * @event: perf event
6044 *
6045 * Release (free) perf_event security info.
6046 */
security_perf_event_free(struct perf_event * event)6047 void security_perf_event_free(struct perf_event *event)
6048 {
6049 kfree(event->security);
6050 event->security = NULL;
6051 }
6052
6053 /**
6054 * security_perf_event_read() - Check if reading a perf event label is allowed
6055 * @event: perf event
6056 *
6057 * Read perf_event security info if allowed.
6058 *
6059 * Return: Returns 0 if permission is granted.
6060 */
security_perf_event_read(struct perf_event * event)6061 int security_perf_event_read(struct perf_event *event)
6062 {
6063 return call_int_hook(perf_event_read, event);
6064 }
6065
6066 /**
6067 * security_perf_event_write() - Check if writing a perf event label is allowed
6068 * @event: perf event
6069 *
6070 * Write perf_event security info if allowed.
6071 *
6072 * Return: Returns 0 if permission is granted.
6073 */
security_perf_event_write(struct perf_event * event)6074 int security_perf_event_write(struct perf_event *event)
6075 {
6076 return call_int_hook(perf_event_write, event);
6077 }
6078 #endif /* CONFIG_PERF_EVENTS */
6079
6080 #ifdef CONFIG_IO_URING
6081 /**
6082 * security_uring_override_creds() - Check if overriding creds is allowed
6083 * @new: new credentials
6084 *
6085 * Check if the current task, executing an io_uring operation, is allowed to
6086 * override it's credentials with @new.
6087 *
6088 * Return: Returns 0 if permission is granted.
6089 */
security_uring_override_creds(const struct cred * new)6090 int security_uring_override_creds(const struct cred *new)
6091 {
6092 return call_int_hook(uring_override_creds, new);
6093 }
6094
6095 /**
6096 * security_uring_sqpoll() - Check if IORING_SETUP_SQPOLL is allowed
6097 *
6098 * Check whether the current task is allowed to spawn a io_uring polling thread
6099 * (IORING_SETUP_SQPOLL).
6100 *
6101 * Return: Returns 0 if permission is granted.
6102 */
security_uring_sqpoll(void)6103 int security_uring_sqpoll(void)
6104 {
6105 return call_int_hook(uring_sqpoll);
6106 }
6107
6108 /**
6109 * security_uring_cmd() - Check if a io_uring passthrough command is allowed
6110 * @ioucmd: command
6111 *
6112 * Check whether the file_operations uring_cmd is allowed to run.
6113 *
6114 * Return: Returns 0 if permission is granted.
6115 */
security_uring_cmd(struct io_uring_cmd * ioucmd)6116 int security_uring_cmd(struct io_uring_cmd *ioucmd)
6117 {
6118 return call_int_hook(uring_cmd, ioucmd);
6119 }
6120
6121 /**
6122 * security_uring_allowed() - Check if io_uring_setup() is allowed
6123 *
6124 * Check whether the current task is allowed to call io_uring_setup().
6125 *
6126 * Return: Returns 0 if permission is granted.
6127 */
security_uring_allowed(void)6128 int security_uring_allowed(void)
6129 {
6130 return call_int_hook(uring_allowed);
6131 }
6132 #endif /* CONFIG_IO_URING */
6133
6134 /**
6135 * security_initramfs_populated() - Notify LSMs that initramfs has been loaded
6136 *
6137 * Tells the LSMs the initramfs has been unpacked into the rootfs.
6138 */
security_initramfs_populated(void)6139 void security_initramfs_populated(void)
6140 {
6141 call_void_hook(initramfs_populated);
6142 }
6143