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 /* set during initialization */ 53 extern int ima_hash_algo __ro_after_init; 54 extern int ima_sha1_idx __ro_after_init; 55 extern int ima_hash_algo_idx __ro_after_init; 56 extern int ima_extra_slots __ro_after_init; 57 extern int ima_appraise; 58 extern struct tpm_chip *ima_tpm_chip; 59 extern const char boot_aggregate_name[]; 60 61 /* IMA event related data */ 62 struct 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 */ 75 struct ima_field_data { 76 u8 *data; 77 u32 len; 78 }; 79 80 /* IMA template field definition */ 81 struct 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 */ 90 struct 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 98 struct 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 }; 105 106 struct 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 }; 111 extern struct list_head ima_measurements; /* list of all measurements */ 112 113 /* Some details preceding the binary serialized measurement list */ 114 struct ima_kexec_hdr { 115 u16 version; 116 u16 _reserved0; 117 u32 _reserved1; 118 u64 buffer_size; 119 u64 count; 120 }; 121 122 extern const int read_idmap[]; 123 124 #ifdef CONFIG_HAVE_IMA_KEXEC 125 void ima_load_kexec_buffer(void); 126 #else 127 static inline void ima_load_kexec_buffer(void) {} 128 #endif /* CONFIG_HAVE_IMA_KEXEC */ 129 130 #ifdef CONFIG_IMA_MEASURE_ASYMMETRIC_KEYS 131 void ima_post_key_create_or_update(struct key *keyring, struct key *key, 132 const void *payload, size_t plen, 133 unsigned long flags, bool create); 134 #endif 135 136 /* 137 * The default binary_runtime_measurements list format is defined as the 138 * platform native format. The canonical format is defined as little-endian. 139 */ 140 extern bool ima_canonical_fmt; 141 142 /* Internal IMA function definitions */ 143 int ima_init(void); 144 int ima_fs_init(void); 145 int ima_add_template_entry(struct ima_template_entry *entry, int violation, 146 const char *op, struct inode *inode, 147 const unsigned char *filename); 148 int ima_calc_file_hash(struct file *file, struct ima_digest_data *hash); 149 int ima_calc_buffer_hash(const void *buf, loff_t len, 150 struct ima_digest_data *hash); 151 int ima_calc_field_array_hash(struct ima_field_data *field_data, 152 struct ima_template_entry *entry); 153 int ima_calc_boot_aggregate(struct ima_digest_data *hash); 154 void ima_add_violation(struct file *file, const unsigned char *filename, 155 struct integrity_iint_cache *iint, 156 const char *op, const char *cause); 157 int ima_init_crypto(void); 158 void ima_putc(struct seq_file *m, void *data, int datalen); 159 void ima_print_digest(struct seq_file *m, u8 *digest, u32 size); 160 int template_desc_init_fields(const char *template_fmt, 161 const struct ima_template_field ***fields, 162 int *num_fields); 163 struct ima_template_desc *ima_template_desc_current(void); 164 struct ima_template_desc *ima_template_desc_buf(void); 165 struct ima_template_desc *lookup_template_desc(const char *name); 166 bool ima_template_has_modsig(const struct ima_template_desc *ima_template); 167 int ima_restore_measurement_entry(struct ima_template_entry *entry); 168 int ima_restore_measurement_list(loff_t bufsize, void *buf); 169 int ima_measurements_show(struct seq_file *m, void *v); 170 unsigned long ima_get_binary_runtime_size(void); 171 int ima_init_template(void); 172 void ima_init_template_list(void); 173 int __init ima_init_digests(void); 174 int ima_lsm_policy_change(struct notifier_block *nb, unsigned long event, 175 void *lsm_data); 176 177 /* 178 * used to protect h_table and sha_table 179 */ 180 extern spinlock_t ima_queue_lock; 181 182 struct ima_h_table { 183 atomic_long_t len; /* number of stored measurements in the list */ 184 atomic_long_t violations; 185 struct hlist_head queue[IMA_MEASURE_HTABLE_SIZE]; 186 }; 187 extern struct ima_h_table ima_htable; 188 189 static inline unsigned int ima_hash_key(u8 *digest) 190 { 191 /* there is no point in taking a hash of part of a digest */ 192 return (digest[0] | digest[1] << 8) % IMA_MEASURE_HTABLE_SIZE; 193 } 194 195 #define __ima_hooks(hook) \ 196 hook(NONE, none) \ 197 hook(FILE_CHECK, file) \ 198 hook(MMAP_CHECK, mmap) \ 199 hook(MMAP_CHECK_REQPROT, mmap_reqprot) \ 200 hook(BPRM_CHECK, bprm) \ 201 hook(CREDS_CHECK, creds) \ 202 hook(POST_SETATTR, post_setattr) \ 203 hook(MODULE_CHECK, module) \ 204 hook(FIRMWARE_CHECK, firmware) \ 205 hook(KEXEC_KERNEL_CHECK, kexec_kernel) \ 206 hook(KEXEC_INITRAMFS_CHECK, kexec_initramfs) \ 207 hook(POLICY_CHECK, policy) \ 208 hook(KEXEC_CMDLINE, kexec_cmdline) \ 209 hook(KEY_CHECK, key) \ 210 hook(CRITICAL_DATA, critical_data) \ 211 hook(SETXATTR_CHECK, setxattr_check) \ 212 hook(MAX_CHECK, none) 213 214 #define __ima_hook_enumify(ENUM, str) ENUM, 215 #define __ima_stringify(arg) (#arg) 216 #define __ima_hook_measuring_stringify(ENUM, str) \ 217 (__ima_stringify(measuring_ ##str)), 218 219 enum ima_hooks { 220 __ima_hooks(__ima_hook_enumify) 221 }; 222 223 static const char * const ima_hooks_measure_str[] = { 224 __ima_hooks(__ima_hook_measuring_stringify) 225 }; 226 227 static inline const char *func_measure_str(enum ima_hooks func) 228 { 229 if (func >= MAX_CHECK) 230 return ima_hooks_measure_str[NONE]; 231 232 return ima_hooks_measure_str[func]; 233 } 234 235 extern const char *const func_tokens[]; 236 237 struct modsig; 238 239 #ifdef CONFIG_IMA_QUEUE_EARLY_BOOT_KEYS 240 /* 241 * To track keys that need to be measured. 242 */ 243 struct ima_key_entry { 244 struct list_head list; 245 void *payload; 246 size_t payload_len; 247 char *keyring_name; 248 }; 249 void ima_init_key_queue(void); 250 bool ima_should_queue_key(void); 251 bool ima_queue_key(struct key *keyring, const void *payload, 252 size_t payload_len); 253 void ima_process_queued_keys(void); 254 #else 255 static inline void ima_init_key_queue(void) {} 256 static inline bool ima_should_queue_key(void) { return false; } 257 static inline bool ima_queue_key(struct key *keyring, 258 const void *payload, 259 size_t payload_len) { return false; } 260 static inline void ima_process_queued_keys(void) {} 261 #endif /* CONFIG_IMA_QUEUE_EARLY_BOOT_KEYS */ 262 263 /* LIM API function definitions */ 264 int ima_get_action(struct mnt_idmap *idmap, struct inode *inode, 265 const struct cred *cred, u32 secid, int mask, 266 enum ima_hooks func, int *pcr, 267 struct ima_template_desc **template_desc, 268 const char *func_data, unsigned int *allowed_algos); 269 int ima_must_measure(struct inode *inode, int mask, enum ima_hooks func); 270 int ima_collect_measurement(struct integrity_iint_cache *iint, 271 struct file *file, void *buf, loff_t size, 272 enum hash_algo algo, struct modsig *modsig); 273 void ima_store_measurement(struct integrity_iint_cache *iint, struct file *file, 274 const unsigned char *filename, 275 struct evm_ima_xattr_data *xattr_value, 276 int xattr_len, const struct modsig *modsig, int pcr, 277 struct ima_template_desc *template_desc); 278 int process_buffer_measurement(struct mnt_idmap *idmap, 279 struct inode *inode, const void *buf, int size, 280 const char *eventname, enum ima_hooks func, 281 int pcr, const char *func_data, 282 bool buf_hash, u8 *digest, size_t digest_len); 283 void ima_audit_measurement(struct integrity_iint_cache *iint, 284 const unsigned char *filename); 285 int ima_alloc_init_template(struct ima_event_data *event_data, 286 struct ima_template_entry **entry, 287 struct ima_template_desc *template_desc); 288 int ima_store_template(struct ima_template_entry *entry, int violation, 289 struct inode *inode, 290 const unsigned char *filename, int pcr); 291 void ima_free_template_entry(struct ima_template_entry *entry); 292 const char *ima_d_path(const struct path *path, char **pathbuf, char *filename); 293 294 /* IMA policy related functions */ 295 int ima_match_policy(struct mnt_idmap *idmap, struct inode *inode, 296 const struct cred *cred, u32 secid, enum ima_hooks func, 297 int mask, int flags, int *pcr, 298 struct ima_template_desc **template_desc, 299 const char *func_data, unsigned int *allowed_algos); 300 void ima_init_policy(void); 301 void ima_update_policy(void); 302 void ima_update_policy_flags(void); 303 ssize_t ima_parse_add_rule(char *); 304 void ima_delete_rules(void); 305 int ima_check_policy(void); 306 void *ima_policy_start(struct seq_file *m, loff_t *pos); 307 void *ima_policy_next(struct seq_file *m, void *v, loff_t *pos); 308 void ima_policy_stop(struct seq_file *m, void *v); 309 int ima_policy_show(struct seq_file *m, void *v); 310 311 /* Appraise integrity measurements */ 312 #define IMA_APPRAISE_ENFORCE 0x01 313 #define IMA_APPRAISE_FIX 0x02 314 #define IMA_APPRAISE_LOG 0x04 315 #define IMA_APPRAISE_MODULES 0x08 316 #define IMA_APPRAISE_FIRMWARE 0x10 317 #define IMA_APPRAISE_POLICY 0x20 318 #define IMA_APPRAISE_KEXEC 0x40 319 320 #ifdef CONFIG_IMA_APPRAISE 321 int ima_check_blacklist(struct integrity_iint_cache *iint, 322 const struct modsig *modsig, int pcr); 323 int ima_appraise_measurement(enum ima_hooks func, 324 struct integrity_iint_cache *iint, 325 struct file *file, const unsigned char *filename, 326 struct evm_ima_xattr_data *xattr_value, 327 int xattr_len, const struct modsig *modsig); 328 int ima_must_appraise(struct mnt_idmap *idmap, struct inode *inode, 329 int mask, enum ima_hooks func); 330 void ima_update_xattr(struct integrity_iint_cache *iint, struct file *file); 331 enum integrity_status ima_get_cache_status(struct integrity_iint_cache *iint, 332 enum ima_hooks func); 333 enum hash_algo ima_get_hash_algo(const struct evm_ima_xattr_data *xattr_value, 334 int xattr_len); 335 int ima_read_xattr(struct dentry *dentry, 336 struct evm_ima_xattr_data **xattr_value, int xattr_len); 337 338 #else 339 static inline int ima_check_blacklist(struct integrity_iint_cache *iint, 340 const struct modsig *modsig, int pcr) 341 { 342 return 0; 343 } 344 345 static inline int ima_appraise_measurement(enum ima_hooks func, 346 struct integrity_iint_cache *iint, 347 struct file *file, 348 const unsigned char *filename, 349 struct evm_ima_xattr_data *xattr_value, 350 int xattr_len, 351 const struct modsig *modsig) 352 { 353 return INTEGRITY_UNKNOWN; 354 } 355 356 static inline int ima_must_appraise(struct mnt_idmap *idmap, 357 struct inode *inode, int mask, 358 enum ima_hooks func) 359 { 360 return 0; 361 } 362 363 static inline void ima_update_xattr(struct integrity_iint_cache *iint, 364 struct file *file) 365 { 366 } 367 368 static inline enum integrity_status ima_get_cache_status(struct integrity_iint_cache 369 *iint, 370 enum ima_hooks func) 371 { 372 return INTEGRITY_UNKNOWN; 373 } 374 375 static inline enum hash_algo 376 ima_get_hash_algo(struct evm_ima_xattr_data *xattr_value, int xattr_len) 377 { 378 return ima_hash_algo; 379 } 380 381 static inline int ima_read_xattr(struct dentry *dentry, 382 struct evm_ima_xattr_data **xattr_value, 383 int xattr_len) 384 { 385 return 0; 386 } 387 388 #endif /* CONFIG_IMA_APPRAISE */ 389 390 #ifdef CONFIG_IMA_APPRAISE_MODSIG 391 int ima_read_modsig(enum ima_hooks func, const void *buf, loff_t buf_len, 392 struct modsig **modsig); 393 void ima_collect_modsig(struct modsig *modsig, const void *buf, loff_t size); 394 int ima_get_modsig_digest(const struct modsig *modsig, enum hash_algo *algo, 395 const u8 **digest, u32 *digest_size); 396 int ima_get_raw_modsig(const struct modsig *modsig, const void **data, 397 u32 *data_len); 398 void ima_free_modsig(struct modsig *modsig); 399 #else 400 static inline int ima_read_modsig(enum ima_hooks func, const void *buf, 401 loff_t buf_len, struct modsig **modsig) 402 { 403 return -EOPNOTSUPP; 404 } 405 406 static inline void ima_collect_modsig(struct modsig *modsig, const void *buf, 407 loff_t size) 408 { 409 } 410 411 static inline int ima_get_modsig_digest(const struct modsig *modsig, 412 enum hash_algo *algo, const u8 **digest, 413 u32 *digest_size) 414 { 415 return -EOPNOTSUPP; 416 } 417 418 static inline int ima_get_raw_modsig(const struct modsig *modsig, 419 const void **data, u32 *data_len) 420 { 421 return -EOPNOTSUPP; 422 } 423 424 static inline void ima_free_modsig(struct modsig *modsig) 425 { 426 } 427 #endif /* CONFIG_IMA_APPRAISE_MODSIG */ 428 429 /* LSM based policy rules require audit */ 430 #ifdef CONFIG_IMA_LSM_RULES 431 432 #define ima_filter_rule_init security_audit_rule_init 433 #define ima_filter_rule_free security_audit_rule_free 434 #define ima_filter_rule_match security_audit_rule_match 435 436 #else 437 438 static inline int ima_filter_rule_init(u32 field, u32 op, char *rulestr, 439 void **lsmrule) 440 { 441 return -EINVAL; 442 } 443 444 static inline void ima_filter_rule_free(void *lsmrule) 445 { 446 } 447 448 static inline int ima_filter_rule_match(u32 secid, u32 field, u32 op, 449 void *lsmrule) 450 { 451 return -EINVAL; 452 } 453 #endif /* CONFIG_IMA_LSM_RULES */ 454 455 #ifdef CONFIG_IMA_READ_POLICY 456 #define POLICY_FILE_FLAGS (S_IWUSR | S_IRUSR) 457 #else 458 #define POLICY_FILE_FLAGS S_IWUSR 459 #endif /* CONFIG_IMA_READ_POLICY */ 460 461 #endif /* __LINUX_IMA_H */ 462