xref: /linux/security/integrity/ima/ima.h (revision de4c44a7f559ceae19f7a70febf49e87bdfb125c)
1 /* SPDX-License-Identifier: GPL-2.0-only */
2 /*
3  * Copyright (C) 2005,2006,2007,2008 IBM Corporation
4  *
5  * Authors:
6  * Reiner Sailer <sailer@watson.ibm.com>
7  * Mimi Zohar <zohar@us.ibm.com>
8  *
9  * File: ima.h
10  *	internal Integrity Measurement Architecture (IMA) definitions
11  */
12 
13 #ifndef __LINUX_IMA_H
14 #define __LINUX_IMA_H
15 
16 #include <linux/types.h>
17 #include <linux/crypto.h>
18 #include <linux/fs.h>
19 #include <linux/security.h>
20 #include <linux/hash.h>
21 #include <linux/tpm.h>
22 #include <linux/audit.h>
23 #include <crypto/hash_info.h>
24 
25 #include "../integrity.h"
26 
27 enum ima_show_type { IMA_SHOW_BINARY, IMA_SHOW_BINARY_NO_FIELD_LEN,
28 		     IMA_SHOW_BINARY_OLD_STRING_FMT, IMA_SHOW_ASCII };
29 enum tpm_pcrs { TPM_PCR0 = 0, TPM_PCR8 = 8, TPM_PCR10 = 10 };
30 
31 /* digest size for IMA, fits SHA1 or MD5 */
32 #define IMA_DIGEST_SIZE		SHA1_DIGEST_SIZE
33 #define IMA_EVENT_NAME_LEN_MAX	255
34 
35 #define IMA_HASH_BITS 10
36 #define IMA_MEASURE_HTABLE_SIZE (1 << IMA_HASH_BITS)
37 
38 #define IMA_TEMPLATE_FIELD_ID_MAX_LEN	16
39 #define IMA_TEMPLATE_NUM_FIELDS_MAX	15
40 
41 #define IMA_TEMPLATE_IMA_NAME "ima"
42 #define IMA_TEMPLATE_IMA_FMT "d|n"
43 
44 #define NR_BANKS(chip) ((chip != NULL) ? chip->nr_allocated_banks : 0)
45 
46 /* current content of the policy */
47 extern int ima_policy_flag;
48 
49 /* bitset of digests algorithms allowed in the setxattr hook */
50 extern atomic_t ima_setxattr_allowed_hash_algorithms;
51 
52 /* IMA hash algorithm description */
53 struct ima_algo_desc {
54 	struct crypto_shash *tfm;
55 	enum hash_algo algo;
56 	unsigned int digest_size;
57 };
58 
59 /* set during initialization */
60 extern int ima_hash_algo __ro_after_init;
61 extern int ima_sha1_idx __ro_after_init;
62 extern int ima_hash_algo_idx __ro_after_init;
63 extern int ima_extra_slots __ro_after_init;
64 extern struct ima_algo_desc *ima_algo_array __ro_after_init;
65 
66 extern int ima_appraise;
67 extern struct tpm_chip *ima_tpm_chip;
68 extern const char boot_aggregate_name[];
69 
70 /* IMA event related data */
71 struct ima_event_data {
72 	struct ima_iint_cache *iint;
73 	struct file *file;
74 	const unsigned char *filename;
75 	struct evm_ima_xattr_data *xattr_value;
76 	int xattr_len;
77 	const struct modsig *modsig;
78 	const char *violation;
79 	const void *buf;
80 	int buf_len;
81 };
82 
83 /* IMA template field data definition */
84 struct ima_field_data {
85 	u8 *data;
86 	u32 len;
87 };
88 
89 /* IMA template field definition */
90 struct ima_template_field {
91 	const char field_id[IMA_TEMPLATE_FIELD_ID_MAX_LEN];
92 	int (*field_init)(struct ima_event_data *event_data,
93 			  struct ima_field_data *field_data);
94 	void (*field_show)(struct seq_file *m, enum ima_show_type show,
95 			   struct ima_field_data *field_data);
96 };
97 
98 /* IMA template descriptor definition */
99 struct ima_template_desc {
100 	struct list_head list;
101 	char *name;
102 	char *fmt;
103 	int num_fields;
104 	const struct ima_template_field **fields;
105 };
106 
107 struct ima_template_entry {
108 	int pcr;
109 	struct tpm_digest *digests;
110 	struct ima_template_desc *template_desc; /* template descriptor */
111 	u32 template_data_len;
112 	struct ima_field_data template_data[];	/* template related data */
113 };
114 
115 struct ima_queue_entry {
116 	struct hlist_node hnext;	/* place in hash collision list */
117 	struct list_head later;		/* place in ima_measurements list */
118 	struct ima_template_entry *entry;
119 };
120 extern struct list_head ima_measurements;	/* list of all measurements */
121 
122 /* Some details preceding the binary serialized measurement list */
123 struct ima_kexec_hdr {
124 	u16 version;
125 	u16 _reserved0;
126 	u32 _reserved1;
127 	u64 buffer_size;
128 	u64 count;
129 };
130 
131 /* IMA iint action cache flags */
132 #define IMA_MEASURE		0x00000001
133 #define IMA_MEASURED		0x00000002
134 #define IMA_APPRAISE		0x00000004
135 #define IMA_APPRAISED		0x00000008
136 /*#define IMA_COLLECT		0x00000010  do not use this flag */
137 #define IMA_COLLECTED		0x00000020
138 #define IMA_AUDIT		0x00000040
139 #define IMA_AUDITED		0x00000080
140 #define IMA_HASH		0x00000100
141 #define IMA_HASHED		0x00000200
142 
143 /* IMA iint policy rule cache flags */
144 #define IMA_NONACTION_FLAGS	0xff000000
145 #define IMA_DIGSIG_REQUIRED	0x01000000
146 #define IMA_PERMIT_DIRECTIO	0x02000000
147 #define IMA_NEW_FILE		0x04000000
148 #define IMA_SIGV3_REQUIRED	0x08000000
149 #define IMA_FAIL_UNVERIFIABLE_SIGS	0x10000000
150 #define IMA_MODSIG_ALLOWED	0x20000000
151 #define IMA_CHECK_BLACKLIST	0x40000000
152 #define IMA_VERITY_REQUIRED	0x80000000
153 
154 /* Exclude non-action flags which are not rule-specific. */
155 #define IMA_NONACTION_RULE_FLAGS	(IMA_NONACTION_FLAGS & ~IMA_NEW_FILE)
156 
157 #define IMA_DO_MASK		(IMA_MEASURE | IMA_APPRAISE | IMA_AUDIT | \
158 				 IMA_HASH | IMA_APPRAISE_SUBMASK)
159 #define IMA_DONE_MASK		(IMA_MEASURED | IMA_APPRAISED | IMA_AUDITED | \
160 				 IMA_HASHED | IMA_COLLECTED | \
161 				 IMA_APPRAISED_SUBMASK)
162 
163 /* IMA iint subaction appraise cache flags */
164 #define IMA_FILE_APPRAISE	0x00001000
165 #define IMA_FILE_APPRAISED	0x00002000
166 #define IMA_MMAP_APPRAISE	0x00004000
167 #define IMA_MMAP_APPRAISED	0x00008000
168 #define IMA_BPRM_APPRAISE	0x00010000
169 #define IMA_BPRM_APPRAISED	0x00020000
170 #define IMA_READ_APPRAISE	0x00040000
171 #define IMA_READ_APPRAISED	0x00080000
172 #define IMA_CREDS_APPRAISE	0x00100000
173 #define IMA_CREDS_APPRAISED	0x00200000
174 #define IMA_APPRAISE_SUBMASK	(IMA_FILE_APPRAISE | IMA_MMAP_APPRAISE | \
175 				 IMA_BPRM_APPRAISE | IMA_READ_APPRAISE | \
176 				 IMA_CREDS_APPRAISE)
177 #define IMA_APPRAISED_SUBMASK	(IMA_FILE_APPRAISED | IMA_MMAP_APPRAISED | \
178 				 IMA_BPRM_APPRAISED | IMA_READ_APPRAISED | \
179 				 IMA_CREDS_APPRAISED)
180 
181 /*
182  * IMA iint cache atomic_flags
183  *
184  * IMA_CHANGE_ATTR - indicates that chATTR() was called (chmod, chown, chgrp)
185  * and file attributes have changed. On file open, it causes IMA to clear
186  * iint->flags to re-evaluate policy and perform IMA functions again.
187  *
188  * IMA_CHANGE_XATTR - indicates that setxattr or removexattr was called and
189  * extended attributes have changed. On file open, it causes IMA to clear
190  * iint->flags IMA_DONE_MASK to re-appraise.
191  *
192  * IMA_UPDATE_XATTR - indicates that security.ima needs to be updated. It is
193  * cleared if file policy changes and no update is needed.
194  *
195  * IMA_DIGSIG - indicates that file security.ima has signature and file
196  * security.ima must not update on file close.
197  *
198  * IMA_MAY_EMIT_TOMTOU - indicates to add Time-of-Measure-Time-of-Use (ToMToU)
199  * integrity violation (a file that is already opened for read is opened for
200  * write) to the measurement list and to also emit an audit message.
201  *
202  * IMA_EMITTED_OPENWRITERS - indicates to add open-writers integrity violation
203  * (a file that is already opened for write is opened for read) to the
204  * measurement list and to also emit an audit message.
205  *
206  */
207 #define IMA_CHANGE_XATTR	0
208 #define IMA_UPDATE_XATTR	1
209 #define IMA_CHANGE_ATTR		2
210 #define IMA_DIGSIG		3
211 #define IMA_MAY_EMIT_TOMTOU	4
212 #define IMA_EMITTED_OPENWRITERS	5
213 
214 /* IMA integrity metadata associated with an inode */
215 struct ima_iint_cache {
216 	struct mutex mutex;	/* protects: version, flags, digest */
217 	struct integrity_inode_attributes real_inode;
218 	unsigned long flags;
219 	unsigned long measured_pcrs;
220 	unsigned long atomic_flags;
221 	enum integrity_status ima_file_status:4;
222 	enum integrity_status ima_mmap_status:4;
223 	enum integrity_status ima_bprm_status:4;
224 	enum integrity_status ima_read_status:4;
225 	enum integrity_status ima_creds_status:4;
226 	struct ima_digest_data *ima_hash;
227 };
228 
229 extern struct lsm_blob_sizes ima_blob_sizes;
230 
231 static inline struct ima_iint_cache *
232 ima_inode_get_iint(const struct inode *inode)
233 {
234 	struct ima_iint_cache **iint_sec;
235 
236 	if (unlikely(!inode->i_security))
237 		return NULL;
238 
239 	iint_sec = inode->i_security + ima_blob_sizes.lbs_inode;
240 	return *iint_sec;
241 }
242 
243 static inline void ima_inode_set_iint(const struct inode *inode,
244 				      struct ima_iint_cache *iint)
245 {
246 	struct ima_iint_cache **iint_sec;
247 
248 	if (unlikely(!inode->i_security))
249 		return;
250 
251 	iint_sec = inode->i_security + ima_blob_sizes.lbs_inode;
252 	*iint_sec = iint;
253 }
254 
255 struct ima_iint_cache *ima_iint_find(struct inode *inode);
256 struct ima_iint_cache *ima_inode_get(struct inode *inode);
257 void ima_inode_free_rcu(void *inode_security);
258 void __init ima_iintcache_init(void);
259 
260 extern const int read_idmap[];
261 
262 #ifdef CONFIG_HAVE_IMA_KEXEC
263 void ima_load_kexec_buffer(void);
264 #else
265 static inline void ima_load_kexec_buffer(void) {}
266 #endif /* CONFIG_HAVE_IMA_KEXEC */
267 
268 #ifdef CONFIG_IMA_MEASURE_ASYMMETRIC_KEYS
269 void ima_post_key_create_or_update(struct key *keyring, struct key *key,
270 				   const void *payload, size_t plen,
271 				   unsigned long flags, bool create);
272 #endif
273 
274 #ifdef CONFIG_IMA_KEXEC
275 void ima_measure_kexec_event(const char *event_name);
276 #else
277 static inline void ima_measure_kexec_event(const char *event_name) {}
278 #endif
279 
280 /*
281  * The default binary_runtime_measurements list format is defined as the
282  * platform native format.  The canonical format is defined as little-endian.
283  */
284 extern bool ima_canonical_fmt;
285 
286 /* Internal IMA function definitions */
287 int ima_init(void);
288 int ima_fs_init(void);
289 int ima_add_template_entry(struct ima_template_entry *entry, int violation,
290 			   const char *op, struct inode *inode,
291 			   const unsigned char *filename);
292 int ima_calc_file_hash(struct file *file, struct ima_digest_data *hash);
293 int ima_calc_buffer_hash(const void *buf, loff_t len,
294 			 struct ima_digest_data *hash);
295 int ima_calc_field_array_hash(struct ima_field_data *field_data,
296 			      struct ima_template_entry *entry);
297 int ima_calc_boot_aggregate(struct ima_digest_data *hash);
298 void ima_add_violation(struct file *file, const unsigned char *filename,
299 		       struct ima_iint_cache *iint, const char *op,
300 		       const char *cause);
301 int ima_init_crypto(void);
302 void ima_putc(struct seq_file *m, void *data, int datalen);
303 void ima_print_digest(struct seq_file *m, u8 *digest, u32 size);
304 int template_desc_init_fields(const char *template_fmt,
305 			      const struct ima_template_field ***fields,
306 			      int *num_fields);
307 struct ima_template_desc *ima_template_desc_current(void);
308 struct ima_template_desc *ima_template_desc_buf(void);
309 struct ima_template_desc *lookup_template_desc(const char *name);
310 bool ima_template_has_modsig(const struct ima_template_desc *ima_template);
311 int ima_restore_measurement_entry(struct ima_template_entry *entry);
312 int ima_restore_measurement_list(loff_t bufsize, void *buf);
313 int ima_measurements_show(struct seq_file *m, void *v);
314 unsigned long ima_get_binary_runtime_size(void);
315 int ima_init_template(void);
316 void ima_init_template_list(void);
317 int __init ima_init_digests(void);
318 void __init ima_init_reboot_notifier(void);
319 int ima_lsm_policy_change(struct notifier_block *nb, unsigned long event,
320 			  void *lsm_data);
321 
322 /*
323  * used to protect h_table and sha_table
324  */
325 extern spinlock_t ima_queue_lock;
326 
327 struct ima_h_table {
328 	atomic_long_t len;	/* number of stored measurements in the list */
329 	atomic_long_t violations;
330 	struct hlist_head queue[IMA_MEASURE_HTABLE_SIZE];
331 };
332 extern struct ima_h_table ima_htable;
333 
334 static inline unsigned int ima_hash_key(u8 *digest)
335 {
336 	/* there is no point in taking a hash of part of a digest */
337 	return (digest[0] | digest[1] << 8) % IMA_MEASURE_HTABLE_SIZE;
338 }
339 
340 #define __ima_hooks(hook)				\
341 	hook(NONE, none)				\
342 	hook(FILE_CHECK, file)				\
343 	hook(MMAP_CHECK, mmap)				\
344 	hook(MMAP_CHECK_REQPROT, mmap_reqprot)		\
345 	hook(BPRM_CHECK, bprm)				\
346 	hook(CREDS_CHECK, creds)			\
347 	hook(POST_SETATTR, post_setattr)		\
348 	hook(MODULE_CHECK, module)			\
349 	hook(FIRMWARE_CHECK, firmware)			\
350 	hook(KEXEC_KERNEL_CHECK, kexec_kernel)		\
351 	hook(KEXEC_INITRAMFS_CHECK, kexec_initramfs)	\
352 	hook(POLICY_CHECK, policy)			\
353 	hook(KEXEC_CMDLINE, kexec_cmdline)		\
354 	hook(KEY_CHECK, key)				\
355 	hook(CRITICAL_DATA, critical_data)		\
356 	hook(SETXATTR_CHECK, setxattr_check)		\
357 	hook(MAX_CHECK, none)
358 
359 #define __ima_hook_enumify(ENUM, str)	ENUM,
360 #define __ima_stringify(arg) (#arg)
361 #define __ima_hook_measuring_stringify(ENUM, str) \
362 		(__ima_stringify(measuring_ ##str)),
363 
364 enum ima_hooks {
365 	__ima_hooks(__ima_hook_enumify)
366 };
367 
368 static const char * const ima_hooks_measure_str[] = {
369 	__ima_hooks(__ima_hook_measuring_stringify)
370 };
371 
372 static inline const char *func_measure_str(enum ima_hooks func)
373 {
374 	if (func >= MAX_CHECK)
375 		return ima_hooks_measure_str[NONE];
376 
377 	return ima_hooks_measure_str[func];
378 }
379 
380 extern const char *const func_tokens[];
381 
382 struct modsig;
383 
384 #ifdef CONFIG_IMA_QUEUE_EARLY_BOOT_KEYS
385 /*
386  * To track keys that need to be measured.
387  */
388 struct ima_key_entry {
389 	struct list_head list;
390 	void *payload;
391 	size_t payload_len;
392 	char *keyring_name;
393 };
394 void ima_init_key_queue(void);
395 bool ima_should_queue_key(void);
396 bool ima_queue_key(struct key *keyring, const void *payload,
397 		   size_t payload_len);
398 void ima_process_queued_keys(void);
399 #else
400 static inline void ima_init_key_queue(void) {}
401 static inline bool ima_should_queue_key(void) { return false; }
402 static inline bool ima_queue_key(struct key *keyring,
403 				 const void *payload,
404 				 size_t payload_len) { return false; }
405 static inline void ima_process_queued_keys(void) {}
406 #endif /* CONFIG_IMA_QUEUE_EARLY_BOOT_KEYS */
407 
408 /* LIM API function definitions */
409 int ima_get_action(struct mnt_idmap *idmap, struct inode *inode,
410 		   const struct cred *cred, struct lsm_prop *prop, int mask,
411 		   enum ima_hooks func, int *pcr,
412 		   struct ima_template_desc **template_desc,
413 		   const char *func_data, unsigned int *allowed_algos);
414 int ima_must_measure(struct inode *inode, int mask, enum ima_hooks func);
415 int ima_collect_measurement(struct ima_iint_cache *iint, struct file *file,
416 			    void *buf, loff_t size, enum hash_algo algo,
417 			    struct modsig *modsig);
418 void ima_store_measurement(struct ima_iint_cache *iint, struct file *file,
419 			   const unsigned char *filename,
420 			   struct evm_ima_xattr_data *xattr_value,
421 			   int xattr_len, const struct modsig *modsig, int pcr,
422 			   struct ima_template_desc *template_desc);
423 int process_buffer_measurement(struct mnt_idmap *idmap,
424 			       struct inode *inode, const void *buf, int size,
425 			       const char *eventname, enum ima_hooks func,
426 			       int pcr, const char *func_data,
427 			       bool buf_hash, u8 *digest, size_t digest_len);
428 void ima_audit_measurement(struct ima_iint_cache *iint,
429 			   const unsigned char *filename);
430 int ima_alloc_init_template(struct ima_event_data *event_data,
431 			    struct ima_template_entry **entry,
432 			    struct ima_template_desc *template_desc);
433 int ima_store_template(struct ima_template_entry *entry, int violation,
434 		       struct inode *inode,
435 		       const unsigned char *filename, int pcr);
436 void ima_free_template_entry(struct ima_template_entry *entry);
437 const char *ima_d_path(const struct path *path, char **pathbuf, char *filename);
438 
439 /* IMA policy related functions */
440 int ima_match_policy(struct mnt_idmap *idmap, struct inode *inode,
441 		     const struct cred *cred, struct lsm_prop *prop,
442 		     enum ima_hooks func, int mask, int flags, int *pcr,
443 		     struct ima_template_desc **template_desc,
444 		     const char *func_data, unsigned int *allowed_algos);
445 void ima_init_policy(void);
446 void ima_update_policy(void);
447 void ima_update_policy_flags(void);
448 ssize_t ima_parse_add_rule(char *);
449 void ima_delete_rules(void);
450 int ima_check_policy(void);
451 void *ima_policy_start(struct seq_file *m, loff_t *pos);
452 void *ima_policy_next(struct seq_file *m, void *v, loff_t *pos);
453 void ima_policy_stop(struct seq_file *m, void *v);
454 int ima_policy_show(struct seq_file *m, void *v);
455 
456 /* Appraise integrity measurements */
457 #define IMA_APPRAISE_ENFORCE	0x01
458 #define IMA_APPRAISE_FIX	0x02
459 #define IMA_APPRAISE_LOG	0x04
460 #define IMA_APPRAISE_MODULES	0x08
461 #define IMA_APPRAISE_FIRMWARE	0x10
462 #define IMA_APPRAISE_POLICY	0x20
463 #define IMA_APPRAISE_KEXEC	0x40
464 
465 #ifdef CONFIG_IMA_APPRAISE
466 int ima_check_blacklist(struct ima_iint_cache *iint,
467 			const struct modsig *modsig, int pcr);
468 int ima_appraise_measurement(enum ima_hooks func, struct ima_iint_cache *iint,
469 			     struct file *file, const unsigned char *filename,
470 			     struct evm_ima_xattr_data *xattr_value,
471 			     int xattr_len, const struct modsig *modsig,
472 			     bool bprm_is_check);
473 int ima_must_appraise(struct mnt_idmap *idmap, struct inode *inode,
474 		      int mask, enum ima_hooks func);
475 void ima_update_xattr(struct ima_iint_cache *iint, struct file *file);
476 enum integrity_status ima_get_cache_status(struct ima_iint_cache *iint,
477 					   enum ima_hooks func);
478 enum hash_algo ima_get_hash_algo(const struct evm_ima_xattr_data *xattr_value,
479 				 int xattr_len);
480 int ima_read_xattr(struct dentry *dentry,
481 		   struct evm_ima_xattr_data **xattr_value, int xattr_len);
482 void __init init_ima_appraise_lsm(const struct lsm_id *lsmid);
483 
484 #else
485 static inline int ima_check_blacklist(struct ima_iint_cache *iint,
486 				      const struct modsig *modsig, int pcr)
487 {
488 	return 0;
489 }
490 
491 static inline int ima_appraise_measurement(enum ima_hooks func,
492 					   struct ima_iint_cache *iint,
493 					   struct file *file,
494 					   const unsigned char *filename,
495 					   struct evm_ima_xattr_data *xattr_value,
496 					   int xattr_len,
497 					   const struct modsig *modsig,
498 					   bool bprm_is_check)
499 {
500 	return INTEGRITY_UNKNOWN;
501 }
502 
503 static inline int ima_must_appraise(struct mnt_idmap *idmap,
504 				    struct inode *inode, int mask,
505 				    enum ima_hooks func)
506 {
507 	return 0;
508 }
509 
510 static inline void ima_update_xattr(struct ima_iint_cache *iint,
511 				    struct file *file)
512 {
513 }
514 
515 static inline enum integrity_status
516 ima_get_cache_status(struct ima_iint_cache *iint, enum ima_hooks func)
517 {
518 	return INTEGRITY_UNKNOWN;
519 }
520 
521 static inline enum hash_algo
522 ima_get_hash_algo(struct evm_ima_xattr_data *xattr_value, int xattr_len)
523 {
524 	return ima_hash_algo;
525 }
526 
527 static inline int ima_read_xattr(struct dentry *dentry,
528 				 struct evm_ima_xattr_data **xattr_value,
529 				 int xattr_len)
530 {
531 	return 0;
532 }
533 
534 static inline void __init init_ima_appraise_lsm(const struct lsm_id *lsmid)
535 {
536 }
537 
538 #endif /* CONFIG_IMA_APPRAISE */
539 
540 #ifdef CONFIG_IMA_APPRAISE_MODSIG
541 int ima_read_modsig(enum ima_hooks func, const void *buf, loff_t buf_len,
542 		    struct modsig **modsig);
543 void ima_collect_modsig(struct modsig *modsig, const void *buf, loff_t size);
544 int ima_get_modsig_digest(const struct modsig *modsig, enum hash_algo *algo,
545 			  const u8 **digest, u32 *digest_size);
546 int ima_get_raw_modsig(const struct modsig *modsig, const void **data,
547 		       u32 *data_len);
548 void ima_free_modsig(struct modsig *modsig);
549 #else
550 static inline int ima_read_modsig(enum ima_hooks func, const void *buf,
551 				  loff_t buf_len, struct modsig **modsig)
552 {
553 	return -EOPNOTSUPP;
554 }
555 
556 static inline void ima_collect_modsig(struct modsig *modsig, const void *buf,
557 				      loff_t size)
558 {
559 }
560 
561 static inline int ima_get_modsig_digest(const struct modsig *modsig,
562 					enum hash_algo *algo, const u8 **digest,
563 					u32 *digest_size)
564 {
565 	return -EOPNOTSUPP;
566 }
567 
568 static inline int ima_get_raw_modsig(const struct modsig *modsig,
569 				     const void **data, u32 *data_len)
570 {
571 	return -EOPNOTSUPP;
572 }
573 
574 static inline void ima_free_modsig(struct modsig *modsig)
575 {
576 }
577 #endif /* CONFIG_IMA_APPRAISE_MODSIG */
578 
579 /* LSM based policy rules require audit */
580 #ifdef CONFIG_IMA_LSM_RULES
581 
582 #define ima_filter_rule_init security_audit_rule_init
583 #define ima_filter_rule_free security_audit_rule_free
584 #define ima_filter_rule_match security_audit_rule_match
585 
586 #else
587 
588 static inline int ima_filter_rule_init(u32 field, u32 op, char *rulestr,
589 				       void **lsmrule, gfp_t gfp)
590 {
591 	return -EINVAL;
592 }
593 
594 static inline void ima_filter_rule_free(void *lsmrule)
595 {
596 }
597 
598 static inline int ima_filter_rule_match(struct lsm_prop *prop, u32 field, u32 op,
599 					void *lsmrule)
600 {
601 	return -EINVAL;
602 }
603 #endif /* CONFIG_IMA_LSM_RULES */
604 
605 #ifdef	CONFIG_IMA_READ_POLICY
606 #define	POLICY_FILE_FLAGS	(S_IWUSR | S_IRUSR)
607 #else
608 #define	POLICY_FILE_FLAGS	S_IWUSR
609 #endif /* CONFIG_IMA_READ_POLICY */
610 
611 #endif /* __LINUX_IMA_H */
612