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
31 enum ima_show_type { IMA_SHOW_BINARY, IMA_SHOW_BINARY_NO_FIELD_LEN,
32 IMA_SHOW_BINARY_OLD_STRING_FMT, IMA_SHOW_ASCII };
33 enum tpm_pcrs { TPM_PCR0 = 0, TPM_PCR8 = 8 };
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 9
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 /* current content of the policy */
49 extern int ima_policy_flag;
50
51 /* set during initialization */
52 extern int ima_hash_algo;
53 extern int ima_appraise;
54 extern struct tpm_chip *ima_tpm_chip;
55
56 /* IMA event related data */
57 struct ima_event_data {
58 struct integrity_iint_cache *iint;
59 struct file *file;
60 const unsigned char *filename;
61 struct evm_ima_xattr_data *xattr_value;
62 int xattr_len;
63 const struct modsig *modsig;
64 const char *violation;
65 const void *buf;
66 int buf_len;
67 };
68
69 /* IMA template field data definition */
70 struct ima_field_data {
71 u8 *data;
72 u32 len;
73 };
74
75 /* IMA template field definition */
76 struct ima_template_field {
77 const char field_id[IMA_TEMPLATE_FIELD_ID_MAX_LEN];
78 int (*field_init)(struct ima_event_data *event_data,
79 struct ima_field_data *field_data);
80 void (*field_show)(struct seq_file *m, enum ima_show_type show,
81 struct ima_field_data *field_data);
82 };
83
84 /* IMA template descriptor definition */
85 struct ima_template_desc {
86 struct list_head list;
87 char *name;
88 char *fmt;
89 int num_fields;
90 const struct ima_template_field **fields;
91 };
92
93 struct ima_template_entry {
94 int pcr;
95 u8 digest[TPM_DIGEST_SIZE]; /* sha1 or md5 measurement hash */
96 struct ima_template_desc *template_desc; /* template descriptor */
97 u32 template_data_len;
98 struct ima_field_data template_data[0]; /* template related data */
99 };
100
101 struct ima_queue_entry {
102 struct hlist_node hnext; /* place in hash collision list */
103 struct list_head later; /* place in ima_measurements list */
104 struct ima_template_entry *entry;
105 };
106 extern struct list_head ima_measurements; /* list of all measurements */
107
108 /* Some details preceding the binary serialized measurement list */
109 struct ima_kexec_hdr {
110 u16 version;
111 u16 _reserved0;
112 u32 _reserved1;
113 u64 buffer_size;
114 u64 count;
115 };
116
117 extern const int read_idmap[];
118
119 #ifdef CONFIG_HAVE_IMA_KEXEC
120 void ima_load_kexec_buffer(void);
121 #else
ima_load_kexec_buffer(void)122 static inline void ima_load_kexec_buffer(void) {}
123 #endif /* CONFIG_HAVE_IMA_KEXEC */
124
125 /*
126 * The default binary_runtime_measurements list format is defined as the
127 * platform native format. The canonical format is defined as little-endian.
128 */
129 extern bool ima_canonical_fmt;
130
131 /* Internal IMA function definitions */
132 int ima_init(void);
133 int ima_fs_init(void);
134 int ima_add_template_entry(struct ima_template_entry *entry, int violation,
135 const char *op, struct inode *inode,
136 const unsigned char *filename);
137 int ima_calc_file_hash(struct file *file, struct ima_digest_data *hash);
138 int ima_calc_buffer_hash(const void *buf, loff_t len,
139 struct ima_digest_data *hash);
140 int ima_calc_field_array_hash(struct ima_field_data *field_data,
141 struct ima_template_desc *desc, int num_fields,
142 struct ima_digest_data *hash);
143 int __init ima_calc_boot_aggregate(struct ima_digest_data *hash);
144 void ima_add_violation(struct file *file, const unsigned char *filename,
145 struct integrity_iint_cache *iint,
146 const char *op, const char *cause);
147 int ima_init_crypto(void);
148 void ima_putc(struct seq_file *m, void *data, int datalen);
149 void ima_print_digest(struct seq_file *m, u8 *digest, u32 size);
150 int template_desc_init_fields(const char *template_fmt,
151 const struct ima_template_field ***fields,
152 int *num_fields);
153 struct ima_template_desc *ima_template_desc_current(void);
154 struct ima_template_desc *lookup_template_desc(const char *name);
155 bool ima_template_has_modsig(const struct ima_template_desc *ima_template);
156 int ima_restore_measurement_entry(struct ima_template_entry *entry);
157 int ima_restore_measurement_list(loff_t bufsize, void *buf);
158 int ima_measurements_show(struct seq_file *m, void *v);
159 unsigned long ima_get_binary_runtime_size(void);
160 int ima_init_template(void);
161 void ima_init_template_list(void);
162 int __init ima_init_digests(void);
163 int ima_lsm_policy_change(struct notifier_block *nb, unsigned long event,
164 void *lsm_data);
165
166 /*
167 * used to protect h_table and sha_table
168 */
169 extern spinlock_t ima_queue_lock;
170
171 struct ima_h_table {
172 atomic_long_t len; /* number of stored measurements in the list */
173 atomic_long_t violations;
174 struct hlist_head queue[IMA_MEASURE_HTABLE_SIZE];
175 };
176 extern struct ima_h_table ima_htable;
177
ima_hash_key(u8 * digest)178 static inline unsigned long ima_hash_key(u8 *digest)
179 {
180 return hash_long(*digest, IMA_HASH_BITS);
181 }
182
183 #define __ima_hooks(hook) \
184 hook(NONE) \
185 hook(FILE_CHECK) \
186 hook(MMAP_CHECK) \
187 hook(BPRM_CHECK) \
188 hook(CREDS_CHECK) \
189 hook(POST_SETATTR) \
190 hook(MODULE_CHECK) \
191 hook(FIRMWARE_CHECK) \
192 hook(KEXEC_KERNEL_CHECK) \
193 hook(KEXEC_INITRAMFS_CHECK) \
194 hook(POLICY_CHECK) \
195 hook(KEXEC_CMDLINE) \
196 hook(MAX_CHECK)
197 #define __ima_hook_enumify(ENUM) ENUM,
198
199 enum ima_hooks {
200 __ima_hooks(__ima_hook_enumify)
201 };
202
203 extern const char *const func_tokens[];
204
205 struct modsig;
206
207 /* LIM API function definitions */
208 int ima_get_action(struct inode *inode, const struct cred *cred, u32 secid,
209 int mask, enum ima_hooks func, int *pcr,
210 struct ima_template_desc **template_desc);
211 int ima_must_measure(struct inode *inode, int mask, enum ima_hooks func);
212 int ima_collect_measurement(struct integrity_iint_cache *iint,
213 struct file *file, void *buf, loff_t size,
214 enum hash_algo algo, struct modsig *modsig);
215 void ima_store_measurement(struct integrity_iint_cache *iint, struct file *file,
216 const unsigned char *filename,
217 struct evm_ima_xattr_data *xattr_value,
218 int xattr_len, const struct modsig *modsig, int pcr,
219 struct ima_template_desc *template_desc);
220 void ima_audit_measurement(struct integrity_iint_cache *iint,
221 const unsigned char *filename);
222 int ima_alloc_init_template(struct ima_event_data *event_data,
223 struct ima_template_entry **entry,
224 struct ima_template_desc *template_desc);
225 int ima_store_template(struct ima_template_entry *entry, int violation,
226 struct inode *inode,
227 const unsigned char *filename, int pcr);
228 void ima_free_template_entry(struct ima_template_entry *entry);
229 const char *ima_d_path(const struct path *path, char **pathbuf, char *filename);
230
231 /* IMA policy related functions */
232 int ima_match_policy(struct inode *inode, const struct cred *cred, u32 secid,
233 enum ima_hooks func, int mask, int flags, int *pcr,
234 struct ima_template_desc **template_desc);
235 void ima_init_policy(void);
236 void ima_update_policy(void);
237 void ima_update_policy_flag(void);
238 ssize_t ima_parse_add_rule(char *);
239 void ima_delete_rules(void);
240 int ima_check_policy(void);
241 void *ima_policy_start(struct seq_file *m, loff_t *pos);
242 void *ima_policy_next(struct seq_file *m, void *v, loff_t *pos);
243 void ima_policy_stop(struct seq_file *m, void *v);
244 int ima_policy_show(struct seq_file *m, void *v);
245
246 /* Appraise integrity measurements */
247 #define IMA_APPRAISE_ENFORCE 0x01
248 #define IMA_APPRAISE_FIX 0x02
249 #define IMA_APPRAISE_LOG 0x04
250 #define IMA_APPRAISE_MODULES 0x08
251 #define IMA_APPRAISE_FIRMWARE 0x10
252 #define IMA_APPRAISE_POLICY 0x20
253 #define IMA_APPRAISE_KEXEC 0x40
254
255 #ifdef CONFIG_IMA_APPRAISE
256 int ima_appraise_measurement(enum ima_hooks func,
257 struct integrity_iint_cache *iint,
258 struct file *file, const unsigned char *filename,
259 struct evm_ima_xattr_data *xattr_value,
260 int xattr_len, const struct modsig *modsig);
261 int ima_must_appraise(struct inode *inode, int mask, enum ima_hooks func);
262 void ima_update_xattr(struct integrity_iint_cache *iint, struct file *file);
263 enum integrity_status ima_get_cache_status(struct integrity_iint_cache *iint,
264 enum ima_hooks func);
265 enum hash_algo ima_get_hash_algo(struct evm_ima_xattr_data *xattr_value,
266 int xattr_len);
267 int ima_read_xattr(struct dentry *dentry,
268 struct evm_ima_xattr_data **xattr_value);
269
270 #else
ima_appraise_measurement(enum ima_hooks func,struct integrity_iint_cache * iint,struct file * file,const unsigned char * filename,struct evm_ima_xattr_data * xattr_value,int xattr_len,const struct modsig * modsig)271 static inline int ima_appraise_measurement(enum ima_hooks func,
272 struct integrity_iint_cache *iint,
273 struct file *file,
274 const unsigned char *filename,
275 struct evm_ima_xattr_data *xattr_value,
276 int xattr_len,
277 const struct modsig *modsig)
278 {
279 return INTEGRITY_UNKNOWN;
280 }
281
ima_must_appraise(struct inode * inode,int mask,enum ima_hooks func)282 static inline int ima_must_appraise(struct inode *inode, int mask,
283 enum ima_hooks func)
284 {
285 return 0;
286 }
287
ima_update_xattr(struct integrity_iint_cache * iint,struct file * file)288 static inline void ima_update_xattr(struct integrity_iint_cache *iint,
289 struct file *file)
290 {
291 }
292
ima_get_cache_status(struct integrity_iint_cache * iint,enum ima_hooks func)293 static inline enum integrity_status ima_get_cache_status(struct integrity_iint_cache
294 *iint,
295 enum ima_hooks func)
296 {
297 return INTEGRITY_UNKNOWN;
298 }
299
300 static inline enum hash_algo
ima_get_hash_algo(struct evm_ima_xattr_data * xattr_value,int xattr_len)301 ima_get_hash_algo(struct evm_ima_xattr_data *xattr_value, int xattr_len)
302 {
303 return ima_hash_algo;
304 }
305
ima_read_xattr(struct dentry * dentry,struct evm_ima_xattr_data ** xattr_value)306 static inline int ima_read_xattr(struct dentry *dentry,
307 struct evm_ima_xattr_data **xattr_value)
308 {
309 return 0;
310 }
311
312 #endif /* CONFIG_IMA_APPRAISE */
313
314 #ifdef CONFIG_IMA_APPRAISE_MODSIG
315 bool ima_hook_supports_modsig(enum ima_hooks func);
316 int ima_read_modsig(enum ima_hooks func, const void *buf, loff_t buf_len,
317 struct modsig **modsig);
318 void ima_collect_modsig(struct modsig *modsig, const void *buf, loff_t size);
319 int ima_get_modsig_digest(const struct modsig *modsig, enum hash_algo *algo,
320 const u8 **digest, u32 *digest_size);
321 int ima_get_raw_modsig(const struct modsig *modsig, const void **data,
322 u32 *data_len);
323 void ima_free_modsig(struct modsig *modsig);
324 #else
ima_hook_supports_modsig(enum ima_hooks func)325 static inline bool ima_hook_supports_modsig(enum ima_hooks func)
326 {
327 return false;
328 }
329
ima_read_modsig(enum ima_hooks func,const void * buf,loff_t buf_len,struct modsig ** modsig)330 static inline int ima_read_modsig(enum ima_hooks func, const void *buf,
331 loff_t buf_len, struct modsig **modsig)
332 {
333 return -EOPNOTSUPP;
334 }
335
ima_collect_modsig(struct modsig * modsig,const void * buf,loff_t size)336 static inline void ima_collect_modsig(struct modsig *modsig, const void *buf,
337 loff_t size)
338 {
339 }
340
ima_get_modsig_digest(const struct modsig * modsig,enum hash_algo * algo,const u8 ** digest,u32 * digest_size)341 static inline int ima_get_modsig_digest(const struct modsig *modsig,
342 enum hash_algo *algo, const u8 **digest,
343 u32 *digest_size)
344 {
345 return -EOPNOTSUPP;
346 }
347
ima_get_raw_modsig(const struct modsig * modsig,const void ** data,u32 * data_len)348 static inline int ima_get_raw_modsig(const struct modsig *modsig,
349 const void **data, u32 *data_len)
350 {
351 return -EOPNOTSUPP;
352 }
353
ima_free_modsig(struct modsig * modsig)354 static inline void ima_free_modsig(struct modsig *modsig)
355 {
356 }
357 #endif /* CONFIG_IMA_APPRAISE_MODSIG */
358
359 /* LSM based policy rules require audit */
360 #ifdef CONFIG_IMA_LSM_RULES
361
362 #define security_filter_rule_init security_audit_rule_init
363 #define security_filter_rule_match security_audit_rule_match
364
365 #else
366
security_filter_rule_init(u32 field,u32 op,char * rulestr,void ** lsmrule)367 static inline int security_filter_rule_init(u32 field, u32 op, char *rulestr,
368 void **lsmrule)
369 {
370 return -EINVAL;
371 }
372
security_filter_rule_match(u32 secid,u32 field,u32 op,void * lsmrule)373 static inline int security_filter_rule_match(u32 secid, u32 field, u32 op,
374 void *lsmrule)
375 {
376 return -EINVAL;
377 }
378 #endif /* CONFIG_IMA_LSM_RULES */
379
380 #ifdef CONFIG_IMA_READ_POLICY
381 #define POLICY_FILE_FLAGS (S_IWUSR | S_IRUSR)
382 #else
383 #define POLICY_FILE_FLAGS S_IWUSR
384 #endif /* CONFIG_IMA_READ_POLICY */
385
386 #endif /* __LINUX_IMA_H */
387