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
27enum ima_show_type { IMA_SHOW_BINARY, IMA_SHOW_BINARY_NO_FIELD_LEN,
28		     IMA_SHOW_BINARY_OLD_STRING_FMT, IMA_SHOW_ASCII };
29enum 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 */
47extern int ima_policy_flag;
48
49/* bitset of digests algorithms allowed in the setxattr hook */
50extern atomic_t ima_setxattr_allowed_hash_algorithms;
51
52/* set during initialization */
53extern int ima_hash_algo __ro_after_init;
54extern int ima_sha1_idx __ro_after_init;
55extern int ima_hash_algo_idx __ro_after_init;
56extern int ima_extra_slots __ro_after_init;
57extern int ima_appraise;
58extern struct tpm_chip *ima_tpm_chip;
59extern const char boot_aggregate_name[];
60
61/* IMA event related data */
62struct ima_event_data {
63	struct integrity_iint_cache *iint;
64	struct file *file;
65	const unsigned char *filename;
66	struct evm_ima_xattr_data *xattr_value;
67	int xattr_len;
68	const struct modsig *modsig;
69	const char *violation;
70	const void *buf;
71	int buf_len;
72};
73
74/* IMA template field data definition */
75struct ima_field_data {
76	u8 *data;
77	u32 len;
78};
79
80/* IMA template field definition */
81struct ima_template_field {
82	const char field_id[IMA_TEMPLATE_FIELD_ID_MAX_LEN];
83	int (*field_init)(struct ima_event_data *event_data,
84			  struct ima_field_data *field_data);
85	void (*field_show)(struct seq_file *m, enum ima_show_type show,
86			   struct ima_field_data *field_data);
87};
88
89/* IMA template descriptor definition */
90struct ima_template_desc {
91	struct list_head list;
92	char *name;
93	char *fmt;
94	int num_fields;
95	const struct ima_template_field **fields;
96};
97
98struct ima_template_entry {
99	int pcr;
100	struct tpm_digest *digests;
101	struct ima_template_desc *template_desc; /* template descriptor */
102	u32 template_data_len;
103	struct ima_field_data template_data[];	/* template related data */
104};
105
106struct ima_queue_entry {
107	struct hlist_node hnext;	/* place in hash collision list */
108	struct list_head later;		/* place in ima_measurements list */
109	struct ima_template_entry *entry;
110};
111extern struct list_head ima_measurements;	/* list of all measurements */
112
113/* Some details preceding the binary serialized measurement list */
114struct ima_kexec_hdr {
115	u16 version;
116	u16 _reserved0;
117	u32 _reserved1;
118	u64 buffer_size;
119	u64 count;
120};
121
122extern const int read_idmap[];
123
124#ifdef CONFIG_HAVE_IMA_KEXEC
125void ima_load_kexec_buffer(void);
126#else
127static inline void ima_load_kexec_buffer(void) {}
128#endif /* CONFIG_HAVE_IMA_KEXEC */
129
130/*
131 * The default binary_runtime_measurements list format is defined as the
132 * platform native format.  The canonical format is defined as little-endian.
133 */
134extern bool ima_canonical_fmt;
135
136/* Internal IMA function definitions */
137int ima_init(void);
138int ima_fs_init(void);
139int ima_add_template_entry(struct ima_template_entry *entry, int violation,
140			   const char *op, struct inode *inode,
141			   const unsigned char *filename);
142int ima_calc_file_hash(struct file *file, struct ima_digest_data *hash);
143int ima_calc_buffer_hash(const void *buf, loff_t len,
144			 struct ima_digest_data *hash);
145int ima_calc_field_array_hash(struct ima_field_data *field_data,
146			      struct ima_template_entry *entry);
147int ima_calc_boot_aggregate(struct ima_digest_data *hash);
148void ima_add_violation(struct file *file, const unsigned char *filename,
149		       struct integrity_iint_cache *iint,
150		       const char *op, const char *cause);
151int ima_init_crypto(void);
152void ima_putc(struct seq_file *m, void *data, int datalen);
153void ima_print_digest(struct seq_file *m, u8 *digest, u32 size);
154int template_desc_init_fields(const char *template_fmt,
155			      const struct ima_template_field ***fields,
156			      int *num_fields);
157struct ima_template_desc *ima_template_desc_current(void);
158struct ima_template_desc *ima_template_desc_buf(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(MMAP_CHECK_REQPROT, mmap_reqprot)		\
194	hook(BPRM_CHECK, bprm)				\
195	hook(CREDS_CHECK, creds)			\
196	hook(POST_SETATTR, post_setattr)		\
197	hook(MODULE_CHECK, module)			\
198	hook(FIRMWARE_CHECK, firmware)			\
199	hook(KEXEC_KERNEL_CHECK, kexec_kernel)		\
200	hook(KEXEC_INITRAMFS_CHECK, kexec_initramfs)	\
201	hook(POLICY_CHECK, policy)			\
202	hook(KEXEC_CMDLINE, kexec_cmdline)		\
203	hook(KEY_CHECK, key)				\
204	hook(CRITICAL_DATA, critical_data)		\
205	hook(SETXATTR_CHECK, setxattr_check)		\
206	hook(MAX_CHECK, none)
207
208#define __ima_hook_enumify(ENUM, str)	ENUM,
209#define __ima_stringify(arg) (#arg)
210#define __ima_hook_measuring_stringify(ENUM, str) \
211		(__ima_stringify(measuring_ ##str)),
212
213enum ima_hooks {
214	__ima_hooks(__ima_hook_enumify)
215};
216
217static const char * const ima_hooks_measure_str[] = {
218	__ima_hooks(__ima_hook_measuring_stringify)
219};
220
221static inline const char *func_measure_str(enum ima_hooks func)
222{
223	if (func >= MAX_CHECK)
224		return ima_hooks_measure_str[NONE];
225
226	return ima_hooks_measure_str[func];
227}
228
229extern const char *const func_tokens[];
230
231struct modsig;
232
233#ifdef CONFIG_IMA_QUEUE_EARLY_BOOT_KEYS
234/*
235 * To track keys that need to be measured.
236 */
237struct ima_key_entry {
238	struct list_head list;
239	void *payload;
240	size_t payload_len;
241	char *keyring_name;
242};
243void ima_init_key_queue(void);
244bool ima_should_queue_key(void);
245bool ima_queue_key(struct key *keyring, const void *payload,
246		   size_t payload_len);
247void ima_process_queued_keys(void);
248#else
249static inline void ima_init_key_queue(void) {}
250static inline bool ima_should_queue_key(void) { return false; }
251static inline bool ima_queue_key(struct key *keyring,
252				 const void *payload,
253				 size_t payload_len) { return false; }
254static inline void ima_process_queued_keys(void) {}
255#endif /* CONFIG_IMA_QUEUE_EARLY_BOOT_KEYS */
256
257/* LIM API function definitions */
258int ima_get_action(struct mnt_idmap *idmap, struct inode *inode,
259		   const struct cred *cred, u32 secid, int mask,
260		   enum ima_hooks func, int *pcr,
261		   struct ima_template_desc **template_desc,
262		   const char *func_data, unsigned int *allowed_algos);
263int ima_must_measure(struct inode *inode, int mask, enum ima_hooks func);
264int ima_collect_measurement(struct integrity_iint_cache *iint,
265			    struct file *file, void *buf, loff_t size,
266			    enum hash_algo algo, struct modsig *modsig);
267void ima_store_measurement(struct integrity_iint_cache *iint, struct file *file,
268			   const unsigned char *filename,
269			   struct evm_ima_xattr_data *xattr_value,
270			   int xattr_len, const struct modsig *modsig, int pcr,
271			   struct ima_template_desc *template_desc);
272int process_buffer_measurement(struct mnt_idmap *idmap,
273			       struct inode *inode, const void *buf, int size,
274			       const char *eventname, enum ima_hooks func,
275			       int pcr, const char *func_data,
276			       bool buf_hash, u8 *digest, size_t digest_len);
277void ima_audit_measurement(struct integrity_iint_cache *iint,
278			   const unsigned char *filename);
279int ima_alloc_init_template(struct ima_event_data *event_data,
280			    struct ima_template_entry **entry,
281			    struct ima_template_desc *template_desc);
282int ima_store_template(struct ima_template_entry *entry, int violation,
283		       struct inode *inode,
284		       const unsigned char *filename, int pcr);
285void ima_free_template_entry(struct ima_template_entry *entry);
286const char *ima_d_path(const struct path *path, char **pathbuf, char *filename);
287
288/* IMA policy related functions */
289int ima_match_policy(struct mnt_idmap *idmap, struct inode *inode,
290		     const struct cred *cred, u32 secid, enum ima_hooks func,
291		     int mask, int flags, int *pcr,
292		     struct ima_template_desc **template_desc,
293		     const char *func_data, unsigned int *allowed_algos);
294void ima_init_policy(void);
295void ima_update_policy(void);
296void ima_update_policy_flags(void);
297ssize_t ima_parse_add_rule(char *);
298void ima_delete_rules(void);
299int ima_check_policy(void);
300void *ima_policy_start(struct seq_file *m, loff_t *pos);
301void *ima_policy_next(struct seq_file *m, void *v, loff_t *pos);
302void ima_policy_stop(struct seq_file *m, void *v);
303int ima_policy_show(struct seq_file *m, void *v);
304
305/* Appraise integrity measurements */
306#define IMA_APPRAISE_ENFORCE	0x01
307#define IMA_APPRAISE_FIX	0x02
308#define IMA_APPRAISE_LOG	0x04
309#define IMA_APPRAISE_MODULES	0x08
310#define IMA_APPRAISE_FIRMWARE	0x10
311#define IMA_APPRAISE_POLICY	0x20
312#define IMA_APPRAISE_KEXEC	0x40
313
314#ifdef CONFIG_IMA_APPRAISE
315int ima_check_blacklist(struct integrity_iint_cache *iint,
316			const struct modsig *modsig, int pcr);
317int ima_appraise_measurement(enum ima_hooks func,
318			     struct integrity_iint_cache *iint,
319			     struct file *file, const unsigned char *filename,
320			     struct evm_ima_xattr_data *xattr_value,
321			     int xattr_len, const struct modsig *modsig);
322int ima_must_appraise(struct mnt_idmap *idmap, struct inode *inode,
323		      int mask, enum ima_hooks func);
324void ima_update_xattr(struct integrity_iint_cache *iint, struct file *file);
325enum integrity_status ima_get_cache_status(struct integrity_iint_cache *iint,
326					   enum ima_hooks func);
327enum hash_algo ima_get_hash_algo(const struct evm_ima_xattr_data *xattr_value,
328				 int xattr_len);
329int ima_read_xattr(struct dentry *dentry,
330		   struct evm_ima_xattr_data **xattr_value, int xattr_len);
331
332#else
333static inline int ima_check_blacklist(struct integrity_iint_cache *iint,
334				      const struct modsig *modsig, int pcr)
335{
336	return 0;
337}
338
339static inline int ima_appraise_measurement(enum ima_hooks func,
340					   struct integrity_iint_cache *iint,
341					   struct file *file,
342					   const unsigned char *filename,
343					   struct evm_ima_xattr_data *xattr_value,
344					   int xattr_len,
345					   const struct modsig *modsig)
346{
347	return INTEGRITY_UNKNOWN;
348}
349
350static inline int ima_must_appraise(struct mnt_idmap *idmap,
351				    struct inode *inode, int mask,
352				    enum ima_hooks func)
353{
354	return 0;
355}
356
357static inline void ima_update_xattr(struct integrity_iint_cache *iint,
358				    struct file *file)
359{
360}
361
362static inline enum integrity_status ima_get_cache_status(struct integrity_iint_cache
363							 *iint,
364							 enum ima_hooks func)
365{
366	return INTEGRITY_UNKNOWN;
367}
368
369static inline enum hash_algo
370ima_get_hash_algo(struct evm_ima_xattr_data *xattr_value, int xattr_len)
371{
372	return ima_hash_algo;
373}
374
375static inline int ima_read_xattr(struct dentry *dentry,
376				 struct evm_ima_xattr_data **xattr_value,
377				 int xattr_len)
378{
379	return 0;
380}
381
382#endif /* CONFIG_IMA_APPRAISE */
383
384#ifdef CONFIG_IMA_APPRAISE_MODSIG
385int ima_read_modsig(enum ima_hooks func, const void *buf, loff_t buf_len,
386		    struct modsig **modsig);
387void ima_collect_modsig(struct modsig *modsig, const void *buf, loff_t size);
388int ima_get_modsig_digest(const struct modsig *modsig, enum hash_algo *algo,
389			  const u8 **digest, u32 *digest_size);
390int ima_get_raw_modsig(const struct modsig *modsig, const void **data,
391		       u32 *data_len);
392void ima_free_modsig(struct modsig *modsig);
393#else
394static inline int ima_read_modsig(enum ima_hooks func, const void *buf,
395				  loff_t buf_len, struct modsig **modsig)
396{
397	return -EOPNOTSUPP;
398}
399
400static inline void ima_collect_modsig(struct modsig *modsig, const void *buf,
401				      loff_t size)
402{
403}
404
405static inline int ima_get_modsig_digest(const struct modsig *modsig,
406					enum hash_algo *algo, const u8 **digest,
407					u32 *digest_size)
408{
409	return -EOPNOTSUPP;
410}
411
412static inline int ima_get_raw_modsig(const struct modsig *modsig,
413				     const void **data, u32 *data_len)
414{
415	return -EOPNOTSUPP;
416}
417
418static inline void ima_free_modsig(struct modsig *modsig)
419{
420}
421#endif /* CONFIG_IMA_APPRAISE_MODSIG */
422
423/* LSM based policy rules require audit */
424#ifdef CONFIG_IMA_LSM_RULES
425
426#define ima_filter_rule_init security_audit_rule_init
427#define ima_filter_rule_free security_audit_rule_free
428#define ima_filter_rule_match security_audit_rule_match
429
430#else
431
432static inline int ima_filter_rule_init(u32 field, u32 op, char *rulestr,
433				       void **lsmrule)
434{
435	return -EINVAL;
436}
437
438static inline void ima_filter_rule_free(void *lsmrule)
439{
440}
441
442static inline int ima_filter_rule_match(u32 secid, u32 field, u32 op,
443					void *lsmrule)
444{
445	return -EINVAL;
446}
447#endif /* CONFIG_IMA_LSM_RULES */
448
449#ifdef	CONFIG_IMA_READ_POLICY
450#define	POLICY_FILE_FLAGS	(S_IWUSR | S_IRUSR)
451#else
452#define	POLICY_FILE_FLAGS	S_IWUSR
453#endif /* CONFIG_IMA_READ_POLICY */
454
455#endif /* __LINUX_IMA_H */
456