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 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 */ 51 extern int ima_policy_flag; 52 53 /* set during initialization */ 54 extern int ima_hash_algo; 55 extern int ima_sha1_idx __ro_after_init; 56 extern int ima_hash_algo_idx __ro_after_init; 57 extern int ima_extra_slots __ro_after_init; 58 extern int ima_appraise; 59 extern struct tpm_chip *ima_tpm_chip; 60 extern const char boot_aggregate_name[]; 61 62 /* IMA event related data */ 63 struct 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 */ 76 struct ima_field_data { 77 u8 *data; 78 u32 len; 79 }; 80 81 /* IMA template field definition */ 82 struct 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 */ 91 struct 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 99 struct 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[0]; /* template related data */ 105 }; 106 107 struct 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 }; 112 extern struct list_head ima_measurements; /* list of all measurements */ 113 114 /* Some details preceding the binary serialized measurement list */ 115 struct ima_kexec_hdr { 116 u16 version; 117 u16 _reserved0; 118 u32 _reserved1; 119 u64 buffer_size; 120 u64 count; 121 }; 122 123 extern const int read_idmap[]; 124 125 #ifdef CONFIG_HAVE_IMA_KEXEC 126 void ima_load_kexec_buffer(void); 127 #else 128 static 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 */ 135 extern bool ima_canonical_fmt; 136 137 /* Internal IMA function definitions */ 138 int ima_init(void); 139 int ima_fs_init(void); 140 int ima_add_template_entry(struct ima_template_entry *entry, int violation, 141 const char *op, struct inode *inode, 142 const unsigned char *filename); 143 int ima_calc_file_hash(struct file *file, struct ima_digest_data *hash); 144 int ima_calc_buffer_hash(const void *buf, loff_t len, 145 struct ima_digest_data *hash); 146 int ima_calc_field_array_hash(struct ima_field_data *field_data, 147 struct ima_template_entry *entry); 148 int ima_calc_boot_aggregate(struct ima_digest_data *hash); 149 void ima_add_violation(struct file *file, const unsigned char *filename, 150 struct integrity_iint_cache *iint, 151 const char *op, const char *cause); 152 int ima_init_crypto(void); 153 void ima_putc(struct seq_file *m, void *data, int datalen); 154 void ima_print_digest(struct seq_file *m, u8 *digest, u32 size); 155 int template_desc_init_fields(const char *template_fmt, 156 const struct ima_template_field ***fields, 157 int *num_fields); 158 struct ima_template_desc *ima_template_desc_current(void); 159 struct ima_template_desc *lookup_template_desc(const char *name); 160 bool ima_template_has_modsig(const struct ima_template_desc *ima_template); 161 int ima_restore_measurement_entry(struct ima_template_entry *entry); 162 int ima_restore_measurement_list(loff_t bufsize, void *buf); 163 int ima_measurements_show(struct seq_file *m, void *v); 164 unsigned long ima_get_binary_runtime_size(void); 165 int ima_init_template(void); 166 void ima_init_template_list(void); 167 int __init ima_init_digests(void); 168 int 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 */ 174 extern spinlock_t ima_queue_lock; 175 176 struct 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 }; 181 extern struct ima_h_table ima_htable; 182 183 static 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) \ 191 hook(FILE_CHECK) \ 192 hook(MMAP_CHECK) \ 193 hook(BPRM_CHECK) \ 194 hook(CREDS_CHECK) \ 195 hook(POST_SETATTR) \ 196 hook(MODULE_CHECK) \ 197 hook(FIRMWARE_CHECK) \ 198 hook(KEXEC_KERNEL_CHECK) \ 199 hook(KEXEC_INITRAMFS_CHECK) \ 200 hook(POLICY_CHECK) \ 201 hook(KEXEC_CMDLINE) \ 202 hook(KEY_CHECK) \ 203 hook(MAX_CHECK) 204 #define __ima_hook_enumify(ENUM) ENUM, 205 206 enum ima_hooks { 207 __ima_hooks(__ima_hook_enumify) 208 }; 209 210 extern const char *const func_tokens[]; 211 212 struct modsig; 213 214 #ifdef CONFIG_IMA_QUEUE_EARLY_BOOT_KEYS 215 /* 216 * To track keys that need to be measured. 217 */ 218 struct ima_key_entry { 219 struct list_head list; 220 void *payload; 221 size_t payload_len; 222 char *keyring_name; 223 }; 224 void ima_init_key_queue(void); 225 bool ima_should_queue_key(void); 226 bool ima_queue_key(struct key *keyring, const void *payload, 227 size_t payload_len); 228 void ima_process_queued_keys(void); 229 #else 230 static inline void ima_init_key_queue(void) {} 231 static inline bool ima_should_queue_key(void) { return false; } 232 static inline bool ima_queue_key(struct key *keyring, 233 const void *payload, 234 size_t payload_len) { return false; } 235 static inline void ima_process_queued_keys(void) {} 236 #endif /* CONFIG_IMA_QUEUE_EARLY_BOOT_KEYS */ 237 238 /* LIM API function definitions */ 239 int ima_get_action(struct inode *inode, const struct cred *cred, u32 secid, 240 int mask, enum ima_hooks func, int *pcr, 241 struct ima_template_desc **template_desc, 242 const char *keyring); 243 int ima_must_measure(struct inode *inode, int mask, enum ima_hooks func); 244 int ima_collect_measurement(struct integrity_iint_cache *iint, 245 struct file *file, void *buf, loff_t size, 246 enum hash_algo algo, struct modsig *modsig); 247 void ima_store_measurement(struct integrity_iint_cache *iint, struct file *file, 248 const unsigned char *filename, 249 struct evm_ima_xattr_data *xattr_value, 250 int xattr_len, const struct modsig *modsig, int pcr, 251 struct ima_template_desc *template_desc); 252 void process_buffer_measurement(const void *buf, int size, 253 const char *eventname, enum ima_hooks func, 254 int pcr, const char *keyring); 255 void ima_audit_measurement(struct integrity_iint_cache *iint, 256 const unsigned char *filename); 257 int ima_alloc_init_template(struct ima_event_data *event_data, 258 struct ima_template_entry **entry, 259 struct ima_template_desc *template_desc); 260 int ima_store_template(struct ima_template_entry *entry, int violation, 261 struct inode *inode, 262 const unsigned char *filename, int pcr); 263 void ima_free_template_entry(struct ima_template_entry *entry); 264 const char *ima_d_path(const struct path *path, char **pathbuf, char *filename); 265 266 /* IMA policy related functions */ 267 int ima_match_policy(struct inode *inode, const struct cred *cred, u32 secid, 268 enum ima_hooks func, int mask, int flags, int *pcr, 269 struct ima_template_desc **template_desc, 270 const char *keyring); 271 void ima_init_policy(void); 272 void ima_update_policy(void); 273 void ima_update_policy_flag(void); 274 ssize_t ima_parse_add_rule(char *); 275 void ima_delete_rules(void); 276 int ima_check_policy(void); 277 void *ima_policy_start(struct seq_file *m, loff_t *pos); 278 void *ima_policy_next(struct seq_file *m, void *v, loff_t *pos); 279 void ima_policy_stop(struct seq_file *m, void *v); 280 int ima_policy_show(struct seq_file *m, void *v); 281 282 /* Appraise integrity measurements */ 283 #define IMA_APPRAISE_ENFORCE 0x01 284 #define IMA_APPRAISE_FIX 0x02 285 #define IMA_APPRAISE_LOG 0x04 286 #define IMA_APPRAISE_MODULES 0x08 287 #define IMA_APPRAISE_FIRMWARE 0x10 288 #define IMA_APPRAISE_POLICY 0x20 289 #define IMA_APPRAISE_KEXEC 0x40 290 291 #ifdef CONFIG_IMA_APPRAISE 292 int ima_check_blacklist(struct integrity_iint_cache *iint, 293 const struct modsig *modsig, int pcr); 294 int ima_appraise_measurement(enum ima_hooks func, 295 struct integrity_iint_cache *iint, 296 struct file *file, const unsigned char *filename, 297 struct evm_ima_xattr_data *xattr_value, 298 int xattr_len, const struct modsig *modsig); 299 int ima_must_appraise(struct inode *inode, int mask, enum ima_hooks func); 300 void ima_update_xattr(struct integrity_iint_cache *iint, struct file *file); 301 enum integrity_status ima_get_cache_status(struct integrity_iint_cache *iint, 302 enum ima_hooks func); 303 enum hash_algo ima_get_hash_algo(struct evm_ima_xattr_data *xattr_value, 304 int xattr_len); 305 int ima_read_xattr(struct dentry *dentry, 306 struct evm_ima_xattr_data **xattr_value); 307 308 #else 309 static inline int ima_check_blacklist(struct integrity_iint_cache *iint, 310 const struct modsig *modsig, int pcr) 311 { 312 return 0; 313 } 314 315 static inline int ima_appraise_measurement(enum ima_hooks func, 316 struct integrity_iint_cache *iint, 317 struct file *file, 318 const unsigned char *filename, 319 struct evm_ima_xattr_data *xattr_value, 320 int xattr_len, 321 const struct modsig *modsig) 322 { 323 return INTEGRITY_UNKNOWN; 324 } 325 326 static inline int ima_must_appraise(struct inode *inode, int mask, 327 enum ima_hooks func) 328 { 329 return 0; 330 } 331 332 static inline void ima_update_xattr(struct integrity_iint_cache *iint, 333 struct file *file) 334 { 335 } 336 337 static inline enum integrity_status ima_get_cache_status(struct integrity_iint_cache 338 *iint, 339 enum ima_hooks func) 340 { 341 return INTEGRITY_UNKNOWN; 342 } 343 344 static inline enum hash_algo 345 ima_get_hash_algo(struct evm_ima_xattr_data *xattr_value, int xattr_len) 346 { 347 return ima_hash_algo; 348 } 349 350 static inline int ima_read_xattr(struct dentry *dentry, 351 struct evm_ima_xattr_data **xattr_value) 352 { 353 return 0; 354 } 355 356 #endif /* CONFIG_IMA_APPRAISE */ 357 358 #ifdef CONFIG_IMA_APPRAISE_MODSIG 359 bool ima_hook_supports_modsig(enum ima_hooks func); 360 int ima_read_modsig(enum ima_hooks func, const void *buf, loff_t buf_len, 361 struct modsig **modsig); 362 void ima_collect_modsig(struct modsig *modsig, const void *buf, loff_t size); 363 int ima_get_modsig_digest(const struct modsig *modsig, enum hash_algo *algo, 364 const u8 **digest, u32 *digest_size); 365 int ima_get_raw_modsig(const struct modsig *modsig, const void **data, 366 u32 *data_len); 367 void ima_free_modsig(struct modsig *modsig); 368 #else 369 static inline bool ima_hook_supports_modsig(enum ima_hooks func) 370 { 371 return false; 372 } 373 374 static inline int ima_read_modsig(enum ima_hooks func, const void *buf, 375 loff_t buf_len, struct modsig **modsig) 376 { 377 return -EOPNOTSUPP; 378 } 379 380 static inline void ima_collect_modsig(struct modsig *modsig, const void *buf, 381 loff_t size) 382 { 383 } 384 385 static inline int ima_get_modsig_digest(const struct modsig *modsig, 386 enum hash_algo *algo, const u8 **digest, 387 u32 *digest_size) 388 { 389 return -EOPNOTSUPP; 390 } 391 392 static inline int ima_get_raw_modsig(const struct modsig *modsig, 393 const void **data, u32 *data_len) 394 { 395 return -EOPNOTSUPP; 396 } 397 398 static inline void ima_free_modsig(struct modsig *modsig) 399 { 400 } 401 #endif /* CONFIG_IMA_APPRAISE_MODSIG */ 402 403 /* LSM based policy rules require audit */ 404 #ifdef CONFIG_IMA_LSM_RULES 405 406 #define security_filter_rule_init security_audit_rule_init 407 #define security_filter_rule_match security_audit_rule_match 408 409 #else 410 411 static inline int security_filter_rule_init(u32 field, u32 op, char *rulestr, 412 void **lsmrule) 413 { 414 return -EINVAL; 415 } 416 417 static inline int security_filter_rule_match(u32 secid, u32 field, u32 op, 418 void *lsmrule) 419 { 420 return -EINVAL; 421 } 422 #endif /* CONFIG_IMA_LSM_RULES */ 423 424 #ifdef CONFIG_IMA_READ_POLICY 425 #define POLICY_FILE_FLAGS (S_IWUSR | S_IRUSR) 426 #else 427 #define POLICY_FILE_FLAGS S_IWUSR 428 #endif /* CONFIG_IMA_READ_POLICY */ 429 430 #endif /* __LINUX_IMA_H */ 431