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#ifdef CONFIG_HAVE_IMA_KEXEC
28#include <asm/ima.h>
29#endif
30
31enum ima_show_type { IMA_SHOW_BINARY, IMA_SHOW_BINARY_NO_FIELD_LEN,
32		     IMA_SHOW_BINARY_OLD_STRING_FMT, IMA_SHOW_ASCII };
33enum tpm_pcrs { TPM_PCR0 = 0, TPM_PCR8 = 8, TPM_PCR10 = 10 };
34
35/* digest size for IMA, fits SHA1 or MD5 */
36#define IMA_DIGEST_SIZE		SHA1_DIGEST_SIZE
37#define IMA_EVENT_NAME_LEN_MAX	255
38
39#define IMA_HASH_BITS 10
40#define IMA_MEASURE_HTABLE_SIZE (1 << IMA_HASH_BITS)
41
42#define IMA_TEMPLATE_FIELD_ID_MAX_LEN	16
43#define IMA_TEMPLATE_NUM_FIELDS_MAX	15
44
45#define IMA_TEMPLATE_IMA_NAME "ima"
46#define IMA_TEMPLATE_IMA_FMT "d|n"
47
48#define NR_BANKS(chip) ((chip != NULL) ? chip->nr_allocated_banks : 0)
49
50/* current content of the policy */
51extern int ima_policy_flag;
52
53/* set during initialization */
54extern int ima_hash_algo;
55extern int ima_sha1_idx __ro_after_init;
56extern int ima_hash_algo_idx __ro_after_init;
57extern int ima_extra_slots __ro_after_init;
58extern int ima_appraise;
59extern struct tpm_chip *ima_tpm_chip;
60extern const char boot_aggregate_name[];
61
62/* IMA event related data */
63struct ima_event_data {
64	struct integrity_iint_cache *iint;
65	struct file *file;
66	const unsigned char *filename;
67	struct evm_ima_xattr_data *xattr_value;
68	int xattr_len;
69	const struct modsig *modsig;
70	const char *violation;
71	const void *buf;
72	int buf_len;
73};
74
75/* IMA template field data definition */
76struct ima_field_data {
77	u8 *data;
78	u32 len;
79};
80
81/* IMA template field definition */
82struct ima_template_field {
83	const char field_id[IMA_TEMPLATE_FIELD_ID_MAX_LEN];
84	int (*field_init)(struct ima_event_data *event_data,
85			  struct ima_field_data *field_data);
86	void (*field_show)(struct seq_file *m, enum ima_show_type show,
87			   struct ima_field_data *field_data);
88};
89
90/* IMA template descriptor definition */
91struct ima_template_desc {
92	struct list_head list;
93	char *name;
94	char *fmt;
95	int num_fields;
96	const struct ima_template_field **fields;
97};
98
99struct ima_template_entry {
100	int pcr;
101	struct tpm_digest *digests;
102	struct ima_template_desc *template_desc; /* template descriptor */
103	u32 template_data_len;
104	struct ima_field_data template_data[];	/* template related data */
105};
106
107struct ima_queue_entry {
108	struct hlist_node hnext;	/* place in hash collision list */
109	struct list_head later;		/* place in ima_measurements list */
110	struct ima_template_entry *entry;
111};
112extern struct list_head ima_measurements;	/* list of all measurements */
113
114/* Some details preceding the binary serialized measurement list */
115struct ima_kexec_hdr {
116	u16 version;
117	u16 _reserved0;
118	u32 _reserved1;
119	u64 buffer_size;
120	u64 count;
121};
122
123extern const int read_idmap[];
124
125#ifdef CONFIG_HAVE_IMA_KEXEC
126void ima_load_kexec_buffer(void);
127#else
128static inline void ima_load_kexec_buffer(void) {}
129#endif /* CONFIG_HAVE_IMA_KEXEC */
130
131/*
132 * The default binary_runtime_measurements list format is defined as the
133 * platform native format.  The canonical format is defined as little-endian.
134 */
135extern bool ima_canonical_fmt;
136
137/* Internal IMA function definitions */
138int ima_init(void);
139int ima_fs_init(void);
140int ima_add_template_entry(struct ima_template_entry *entry, int violation,
141			   const char *op, struct inode *inode,
142			   const unsigned char *filename);
143int ima_calc_file_hash(struct file *file, struct ima_digest_data *hash);
144int ima_calc_buffer_hash(const void *buf, loff_t len,
145			 struct ima_digest_data *hash);
146int ima_calc_field_array_hash(struct ima_field_data *field_data,
147			      struct ima_template_entry *entry);
148int ima_calc_boot_aggregate(struct ima_digest_data *hash);
149void ima_add_violation(struct file *file, const unsigned char *filename,
150		       struct integrity_iint_cache *iint,
151		       const char *op, const char *cause);
152int ima_init_crypto(void);
153void ima_putc(struct seq_file *m, void *data, int datalen);
154void ima_print_digest(struct seq_file *m, u8 *digest, u32 size);
155int template_desc_init_fields(const char *template_fmt,
156			      const struct ima_template_field ***fields,
157			      int *num_fields);
158struct ima_template_desc *ima_template_desc_current(void);
159struct ima_template_desc *lookup_template_desc(const char *name);
160bool ima_template_has_modsig(const struct ima_template_desc *ima_template);
161int ima_restore_measurement_entry(struct ima_template_entry *entry);
162int ima_restore_measurement_list(loff_t bufsize, void *buf);
163int ima_measurements_show(struct seq_file *m, void *v);
164unsigned long ima_get_binary_runtime_size(void);
165int ima_init_template(void);
166void ima_init_template_list(void);
167int __init ima_init_digests(void);
168int ima_lsm_policy_change(struct notifier_block *nb, unsigned long event,
169			  void *lsm_data);
170
171/*
172 * used to protect h_table and sha_table
173 */
174extern spinlock_t ima_queue_lock;
175
176struct ima_h_table {
177	atomic_long_t len;	/* number of stored measurements in the list */
178	atomic_long_t violations;
179	struct hlist_head queue[IMA_MEASURE_HTABLE_SIZE];
180};
181extern struct ima_h_table ima_htable;
182
183static inline unsigned int ima_hash_key(u8 *digest)
184{
185	/* there is no point in taking a hash of part of a digest */
186	return (digest[0] | digest[1] << 8) % IMA_MEASURE_HTABLE_SIZE;
187}
188
189#define __ima_hooks(hook)				\
190	hook(NONE, none)				\
191	hook(FILE_CHECK, file)				\
192	hook(MMAP_CHECK, mmap)				\
193	hook(BPRM_CHECK, bprm)				\
194	hook(CREDS_CHECK, creds)			\
195	hook(POST_SETATTR, post_setattr)		\
196	hook(MODULE_CHECK, module)			\
197	hook(FIRMWARE_CHECK, firmware)			\
198	hook(KEXEC_KERNEL_CHECK, kexec_kernel)		\
199	hook(KEXEC_INITRAMFS_CHECK, kexec_initramfs)	\
200	hook(POLICY_CHECK, policy)			\
201	hook(KEXEC_CMDLINE, kexec_cmdline)		\
202	hook(KEY_CHECK, key)				\
203	hook(MAX_CHECK, none)
204
205#define __ima_hook_enumify(ENUM, str)	ENUM,
206#define __ima_stringify(arg) (#arg)
207#define __ima_hook_measuring_stringify(ENUM, str) \
208		(__ima_stringify(measuring_ ##str)),
209
210enum ima_hooks {
211	__ima_hooks(__ima_hook_enumify)
212};
213
214static const char * const ima_hooks_measure_str[] = {
215	__ima_hooks(__ima_hook_measuring_stringify)
216};
217
218static inline const char *func_measure_str(enum ima_hooks func)
219{
220	if (func >= MAX_CHECK)
221		return ima_hooks_measure_str[NONE];
222
223	return ima_hooks_measure_str[func];
224}
225
226extern const char *const func_tokens[];
227
228struct modsig;
229
230#ifdef CONFIG_IMA_QUEUE_EARLY_BOOT_KEYS
231/*
232 * To track keys that need to be measured.
233 */
234struct ima_key_entry {
235	struct list_head list;
236	void *payload;
237	size_t payload_len;
238	char *keyring_name;
239};
240void ima_init_key_queue(void);
241bool ima_should_queue_key(void);
242bool ima_queue_key(struct key *keyring, const void *payload,
243		   size_t payload_len);
244void ima_process_queued_keys(void);
245#else
246static inline void ima_init_key_queue(void) {}
247static inline bool ima_should_queue_key(void) { return false; }
248static inline bool ima_queue_key(struct key *keyring,
249				 const void *payload,
250				 size_t payload_len) { return false; }
251static inline void ima_process_queued_keys(void) {}
252#endif /* CONFIG_IMA_QUEUE_EARLY_BOOT_KEYS */
253
254/* LIM API function definitions */
255int ima_get_action(struct inode *inode, const struct cred *cred, u32 secid,
256		   int mask, enum ima_hooks func, int *pcr,
257		   struct ima_template_desc **template_desc,
258		   const char *keyring);
259int ima_must_measure(struct inode *inode, int mask, enum ima_hooks func);
260int ima_collect_measurement(struct integrity_iint_cache *iint,
261			    struct file *file, void *buf, loff_t size,
262			    enum hash_algo algo, struct modsig *modsig);
263void ima_store_measurement(struct integrity_iint_cache *iint, struct file *file,
264			   const unsigned char *filename,
265			   struct evm_ima_xattr_data *xattr_value,
266			   int xattr_len, const struct modsig *modsig, int pcr,
267			   struct ima_template_desc *template_desc);
268void process_buffer_measurement(struct inode *inode, const void *buf, int size,
269				const char *eventname, enum ima_hooks func,
270				int pcr, const char *keyring);
271void ima_audit_measurement(struct integrity_iint_cache *iint,
272			   const unsigned char *filename);
273int ima_alloc_init_template(struct ima_event_data *event_data,
274			    struct ima_template_entry **entry,
275			    struct ima_template_desc *template_desc);
276int ima_store_template(struct ima_template_entry *entry, int violation,
277		       struct inode *inode,
278		       const unsigned char *filename, int pcr);
279void ima_free_template_entry(struct ima_template_entry *entry);
280const char *ima_d_path(const struct path *path, char **pathbuf, char *filename);
281
282/* IMA policy related functions */
283int ima_match_policy(struct inode *inode, const struct cred *cred, u32 secid,
284		     enum ima_hooks func, int mask, int flags, int *pcr,
285		     struct ima_template_desc **template_desc,
286		     const char *keyring);
287void ima_init_policy(void);
288void ima_update_policy(void);
289void ima_update_policy_flag(void);
290ssize_t ima_parse_add_rule(char *);
291void ima_delete_rules(void);
292int ima_check_policy(void);
293void *ima_policy_start(struct seq_file *m, loff_t *pos);
294void *ima_policy_next(struct seq_file *m, void *v, loff_t *pos);
295void ima_policy_stop(struct seq_file *m, void *v);
296int ima_policy_show(struct seq_file *m, void *v);
297
298/* Appraise integrity measurements */
299#define IMA_APPRAISE_ENFORCE	0x01
300#define IMA_APPRAISE_FIX	0x02
301#define IMA_APPRAISE_LOG	0x04
302#define IMA_APPRAISE_MODULES	0x08
303#define IMA_APPRAISE_FIRMWARE	0x10
304#define IMA_APPRAISE_POLICY	0x20
305#define IMA_APPRAISE_KEXEC	0x40
306
307#ifdef CONFIG_IMA_APPRAISE
308int ima_check_blacklist(struct integrity_iint_cache *iint,
309			const struct modsig *modsig, int pcr);
310int ima_appraise_measurement(enum ima_hooks func,
311			     struct integrity_iint_cache *iint,
312			     struct file *file, const unsigned char *filename,
313			     struct evm_ima_xattr_data *xattr_value,
314			     int xattr_len, const struct modsig *modsig);
315int ima_must_appraise(struct inode *inode, int mask, enum ima_hooks func);
316void ima_update_xattr(struct integrity_iint_cache *iint, struct file *file);
317enum integrity_status ima_get_cache_status(struct integrity_iint_cache *iint,
318					   enum ima_hooks func);
319enum hash_algo ima_get_hash_algo(struct evm_ima_xattr_data *xattr_value,
320				 int xattr_len);
321int ima_read_xattr(struct dentry *dentry,
322		   struct evm_ima_xattr_data **xattr_value);
323
324#else
325static inline int ima_check_blacklist(struct integrity_iint_cache *iint,
326				      const struct modsig *modsig, int pcr)
327{
328	return 0;
329}
330
331static inline int ima_appraise_measurement(enum ima_hooks func,
332					   struct integrity_iint_cache *iint,
333					   struct file *file,
334					   const unsigned char *filename,
335					   struct evm_ima_xattr_data *xattr_value,
336					   int xattr_len,
337					   const struct modsig *modsig)
338{
339	return INTEGRITY_UNKNOWN;
340}
341
342static inline int ima_must_appraise(struct inode *inode, int mask,
343				    enum ima_hooks func)
344{
345	return 0;
346}
347
348static inline void ima_update_xattr(struct integrity_iint_cache *iint,
349				    struct file *file)
350{
351}
352
353static inline enum integrity_status ima_get_cache_status(struct integrity_iint_cache
354							 *iint,
355							 enum ima_hooks func)
356{
357	return INTEGRITY_UNKNOWN;
358}
359
360static inline enum hash_algo
361ima_get_hash_algo(struct evm_ima_xattr_data *xattr_value, int xattr_len)
362{
363	return ima_hash_algo;
364}
365
366static inline int ima_read_xattr(struct dentry *dentry,
367				 struct evm_ima_xattr_data **xattr_value)
368{
369	return 0;
370}
371
372#endif /* CONFIG_IMA_APPRAISE */
373
374#ifdef CONFIG_IMA_APPRAISE_MODSIG
375int ima_read_modsig(enum ima_hooks func, const void *buf, loff_t buf_len,
376		    struct modsig **modsig);
377void ima_collect_modsig(struct modsig *modsig, const void *buf, loff_t size);
378int ima_get_modsig_digest(const struct modsig *modsig, enum hash_algo *algo,
379			  const u8 **digest, u32 *digest_size);
380int ima_get_raw_modsig(const struct modsig *modsig, const void **data,
381		       u32 *data_len);
382void ima_free_modsig(struct modsig *modsig);
383#else
384static inline int ima_read_modsig(enum ima_hooks func, const void *buf,
385				  loff_t buf_len, struct modsig **modsig)
386{
387	return -EOPNOTSUPP;
388}
389
390static inline void ima_collect_modsig(struct modsig *modsig, const void *buf,
391				      loff_t size)
392{
393}
394
395static inline int ima_get_modsig_digest(const struct modsig *modsig,
396					enum hash_algo *algo, const u8 **digest,
397					u32 *digest_size)
398{
399	return -EOPNOTSUPP;
400}
401
402static inline int ima_get_raw_modsig(const struct modsig *modsig,
403				     const void **data, u32 *data_len)
404{
405	return -EOPNOTSUPP;
406}
407
408static inline void ima_free_modsig(struct modsig *modsig)
409{
410}
411#endif /* CONFIG_IMA_APPRAISE_MODSIG */
412
413/* LSM based policy rules require audit */
414#ifdef CONFIG_IMA_LSM_RULES
415
416#define ima_filter_rule_init security_audit_rule_init
417#define ima_filter_rule_free security_audit_rule_free
418#define ima_filter_rule_match security_audit_rule_match
419
420#else
421
422static inline int ima_filter_rule_init(u32 field, u32 op, char *rulestr,
423				       void **lsmrule)
424{
425	return -EINVAL;
426}
427
428static inline void ima_filter_rule_free(void *lsmrule)
429{
430}
431
432static inline int ima_filter_rule_match(u32 secid, u32 field, u32 op,
433					void *lsmrule)
434{
435	return -EINVAL;
436}
437#endif /* CONFIG_IMA_LSM_RULES */
438
439#ifdef	CONFIG_IMA_READ_POLICY
440#define	POLICY_FILE_FLAGS	(S_IWUSR | S_IRUSR)
441#else
442#define	POLICY_FILE_FLAGS	S_IWUSR
443#endif /* CONFIG_IMA_READ_POLICY */
444
445#endif /* __LINUX_IMA_H */
446