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 /* IMA hash algorithm description */ 53 struct ima_algo_desc { 54 struct crypto_shash *tfm; 55 enum hash_algo algo; 56 }; 57 58 /* set during initialization */ 59 extern int ima_hash_algo __ro_after_init; 60 extern int ima_sha1_idx __ro_after_init; 61 extern int ima_hash_algo_idx __ro_after_init; 62 extern int ima_extra_slots __ro_after_init; 63 extern struct ima_algo_desc *ima_algo_array __ro_after_init; 64 65 extern int ima_appraise; 66 extern struct tpm_chip *ima_tpm_chip; 67 extern const char boot_aggregate_name[]; 68 69 /* IMA event related data */ 70 struct ima_event_data { 71 struct ima_iint_cache *iint; 72 struct file *file; 73 const unsigned char *filename; 74 struct evm_ima_xattr_data *xattr_value; 75 int xattr_len; 76 const struct modsig *modsig; 77 const char *violation; 78 const void *buf; 79 int buf_len; 80 }; 81 82 /* IMA template field data definition */ 83 struct ima_field_data { 84 u8 *data; 85 u32 len; 86 }; 87 88 /* IMA template field definition */ 89 struct ima_template_field { 90 const char field_id[IMA_TEMPLATE_FIELD_ID_MAX_LEN]; 91 int (*field_init)(struct ima_event_data *event_data, 92 struct ima_field_data *field_data); 93 void (*field_show)(struct seq_file *m, enum ima_show_type show, 94 struct ima_field_data *field_data); 95 }; 96 97 /* IMA template descriptor definition */ 98 struct ima_template_desc { 99 struct list_head list; 100 char *name; 101 char *fmt; 102 int num_fields; 103 const struct ima_template_field **fields; 104 }; 105 106 struct ima_template_entry { 107 int pcr; 108 struct tpm_digest *digests; 109 struct ima_template_desc *template_desc; /* template descriptor */ 110 u32 template_data_len; 111 struct ima_field_data template_data[]; /* template related data */ 112 }; 113 114 struct ima_queue_entry { 115 struct hlist_node hnext; /* place in hash collision list */ 116 struct list_head later; /* place in ima_measurements list */ 117 struct ima_template_entry *entry; 118 }; 119 extern struct list_head ima_measurements; /* list of all measurements */ 120 121 /* Some details preceding the binary serialized measurement list */ 122 struct ima_kexec_hdr { 123 u16 version; 124 u16 _reserved0; 125 u32 _reserved1; 126 u64 buffer_size; 127 u64 count; 128 }; 129 130 /* IMA iint action cache flags */ 131 #define IMA_MEASURE 0x00000001 132 #define IMA_MEASURED 0x00000002 133 #define IMA_APPRAISE 0x00000004 134 #define IMA_APPRAISED 0x00000008 135 /*#define IMA_COLLECT 0x00000010 do not use this flag */ 136 #define IMA_COLLECTED 0x00000020 137 #define IMA_AUDIT 0x00000040 138 #define IMA_AUDITED 0x00000080 139 #define IMA_HASH 0x00000100 140 #define IMA_HASHED 0x00000200 141 142 /* IMA iint policy rule cache flags */ 143 #define IMA_NONACTION_FLAGS 0xff000000 144 #define IMA_DIGSIG_REQUIRED 0x01000000 145 #define IMA_PERMIT_DIRECTIO 0x02000000 146 #define IMA_NEW_FILE 0x04000000 147 #define IMA_FAIL_UNVERIFIABLE_SIGS 0x10000000 148 #define IMA_MODSIG_ALLOWED 0x20000000 149 #define IMA_CHECK_BLACKLIST 0x40000000 150 #define IMA_VERITY_REQUIRED 0x80000000 151 152 /* Exclude non-action flags which are not rule-specific. */ 153 #define IMA_NONACTION_RULE_FLAGS (IMA_NONACTION_FLAGS & ~IMA_NEW_FILE) 154 155 #define IMA_DO_MASK (IMA_MEASURE | IMA_APPRAISE | IMA_AUDIT | \ 156 IMA_HASH | IMA_APPRAISE_SUBMASK) 157 #define IMA_DONE_MASK (IMA_MEASURED | IMA_APPRAISED | IMA_AUDITED | \ 158 IMA_HASHED | IMA_COLLECTED | \ 159 IMA_APPRAISED_SUBMASK) 160 161 /* IMA iint subaction appraise cache flags */ 162 #define IMA_FILE_APPRAISE 0x00001000 163 #define IMA_FILE_APPRAISED 0x00002000 164 #define IMA_MMAP_APPRAISE 0x00004000 165 #define IMA_MMAP_APPRAISED 0x00008000 166 #define IMA_BPRM_APPRAISE 0x00010000 167 #define IMA_BPRM_APPRAISED 0x00020000 168 #define IMA_READ_APPRAISE 0x00040000 169 #define IMA_READ_APPRAISED 0x00080000 170 #define IMA_CREDS_APPRAISE 0x00100000 171 #define IMA_CREDS_APPRAISED 0x00200000 172 #define IMA_APPRAISE_SUBMASK (IMA_FILE_APPRAISE | IMA_MMAP_APPRAISE | \ 173 IMA_BPRM_APPRAISE | IMA_READ_APPRAISE | \ 174 IMA_CREDS_APPRAISE) 175 #define IMA_APPRAISED_SUBMASK (IMA_FILE_APPRAISED | IMA_MMAP_APPRAISED | \ 176 IMA_BPRM_APPRAISED | IMA_READ_APPRAISED | \ 177 IMA_CREDS_APPRAISED) 178 179 /* IMA iint cache atomic_flags */ 180 #define IMA_CHANGE_XATTR 0 181 #define IMA_UPDATE_XATTR 1 182 #define IMA_CHANGE_ATTR 2 183 #define IMA_DIGSIG 3 184 #define IMA_MUST_MEASURE 4 185 186 /* IMA integrity metadata associated with an inode */ 187 struct ima_iint_cache { 188 struct mutex mutex; /* protects: version, flags, digest */ 189 struct integrity_inode_attributes real_inode; 190 unsigned long flags; 191 unsigned long measured_pcrs; 192 unsigned long atomic_flags; 193 enum integrity_status ima_file_status:4; 194 enum integrity_status ima_mmap_status:4; 195 enum integrity_status ima_bprm_status:4; 196 enum integrity_status ima_read_status:4; 197 enum integrity_status ima_creds_status:4; 198 struct ima_digest_data *ima_hash; 199 }; 200 201 extern struct lsm_blob_sizes ima_blob_sizes; 202 203 static inline struct ima_iint_cache * 204 ima_inode_get_iint(const struct inode *inode) 205 { 206 struct ima_iint_cache **iint_sec; 207 208 if (unlikely(!inode->i_security)) 209 return NULL; 210 211 iint_sec = inode->i_security + ima_blob_sizes.lbs_inode; 212 return *iint_sec; 213 } 214 215 static inline void ima_inode_set_iint(const struct inode *inode, 216 struct ima_iint_cache *iint) 217 { 218 struct ima_iint_cache **iint_sec; 219 220 if (unlikely(!inode->i_security)) 221 return; 222 223 iint_sec = inode->i_security + ima_blob_sizes.lbs_inode; 224 *iint_sec = iint; 225 } 226 227 struct ima_iint_cache *ima_iint_find(struct inode *inode); 228 struct ima_iint_cache *ima_inode_get(struct inode *inode); 229 void ima_inode_free_rcu(void *inode_security); 230 void __init ima_iintcache_init(void); 231 232 extern const int read_idmap[]; 233 234 #ifdef CONFIG_HAVE_IMA_KEXEC 235 void ima_load_kexec_buffer(void); 236 #else 237 static inline void ima_load_kexec_buffer(void) {} 238 #endif /* CONFIG_HAVE_IMA_KEXEC */ 239 240 #ifdef CONFIG_IMA_MEASURE_ASYMMETRIC_KEYS 241 void ima_post_key_create_or_update(struct key *keyring, struct key *key, 242 const void *payload, size_t plen, 243 unsigned long flags, bool create); 244 #endif 245 246 /* 247 * The default binary_runtime_measurements list format is defined as the 248 * platform native format. The canonical format is defined as little-endian. 249 */ 250 extern bool ima_canonical_fmt; 251 252 /* Internal IMA function definitions */ 253 int ima_init(void); 254 int ima_fs_init(void); 255 int ima_add_template_entry(struct ima_template_entry *entry, int violation, 256 const char *op, struct inode *inode, 257 const unsigned char *filename); 258 int ima_calc_file_hash(struct file *file, struct ima_digest_data *hash); 259 int ima_calc_buffer_hash(const void *buf, loff_t len, 260 struct ima_digest_data *hash); 261 int ima_calc_field_array_hash(struct ima_field_data *field_data, 262 struct ima_template_entry *entry); 263 int ima_calc_boot_aggregate(struct ima_digest_data *hash); 264 void ima_add_violation(struct file *file, const unsigned char *filename, 265 struct ima_iint_cache *iint, const char *op, 266 const char *cause); 267 int ima_init_crypto(void); 268 void ima_putc(struct seq_file *m, void *data, int datalen); 269 void ima_print_digest(struct seq_file *m, u8 *digest, u32 size); 270 int template_desc_init_fields(const char *template_fmt, 271 const struct ima_template_field ***fields, 272 int *num_fields); 273 struct ima_template_desc *ima_template_desc_current(void); 274 struct ima_template_desc *ima_template_desc_buf(void); 275 struct ima_template_desc *lookup_template_desc(const char *name); 276 bool ima_template_has_modsig(const struct ima_template_desc *ima_template); 277 int ima_restore_measurement_entry(struct ima_template_entry *entry); 278 int ima_restore_measurement_list(loff_t bufsize, void *buf); 279 int ima_measurements_show(struct seq_file *m, void *v); 280 unsigned long ima_get_binary_runtime_size(void); 281 int ima_init_template(void); 282 void ima_init_template_list(void); 283 int __init ima_init_digests(void); 284 void __init ima_init_reboot_notifier(void); 285 int ima_lsm_policy_change(struct notifier_block *nb, unsigned long event, 286 void *lsm_data); 287 288 /* 289 * used to protect h_table and sha_table 290 */ 291 extern spinlock_t ima_queue_lock; 292 293 struct ima_h_table { 294 atomic_long_t len; /* number of stored measurements in the list */ 295 atomic_long_t violations; 296 struct hlist_head queue[IMA_MEASURE_HTABLE_SIZE]; 297 }; 298 extern struct ima_h_table ima_htable; 299 300 static inline unsigned int ima_hash_key(u8 *digest) 301 { 302 /* there is no point in taking a hash of part of a digest */ 303 return (digest[0] | digest[1] << 8) % IMA_MEASURE_HTABLE_SIZE; 304 } 305 306 #define __ima_hooks(hook) \ 307 hook(NONE, none) \ 308 hook(FILE_CHECK, file) \ 309 hook(MMAP_CHECK, mmap) \ 310 hook(MMAP_CHECK_REQPROT, mmap_reqprot) \ 311 hook(BPRM_CHECK, bprm) \ 312 hook(CREDS_CHECK, creds) \ 313 hook(POST_SETATTR, post_setattr) \ 314 hook(MODULE_CHECK, module) \ 315 hook(FIRMWARE_CHECK, firmware) \ 316 hook(KEXEC_KERNEL_CHECK, kexec_kernel) \ 317 hook(KEXEC_INITRAMFS_CHECK, kexec_initramfs) \ 318 hook(POLICY_CHECK, policy) \ 319 hook(KEXEC_CMDLINE, kexec_cmdline) \ 320 hook(KEY_CHECK, key) \ 321 hook(CRITICAL_DATA, critical_data) \ 322 hook(SETXATTR_CHECK, setxattr_check) \ 323 hook(MAX_CHECK, none) 324 325 #define __ima_hook_enumify(ENUM, str) ENUM, 326 #define __ima_stringify(arg) (#arg) 327 #define __ima_hook_measuring_stringify(ENUM, str) \ 328 (__ima_stringify(measuring_ ##str)), 329 330 enum ima_hooks { 331 __ima_hooks(__ima_hook_enumify) 332 }; 333 334 static const char * const ima_hooks_measure_str[] = { 335 __ima_hooks(__ima_hook_measuring_stringify) 336 }; 337 338 static inline const char *func_measure_str(enum ima_hooks func) 339 { 340 if (func >= MAX_CHECK) 341 return ima_hooks_measure_str[NONE]; 342 343 return ima_hooks_measure_str[func]; 344 } 345 346 extern const char *const func_tokens[]; 347 348 struct modsig; 349 350 #ifdef CONFIG_IMA_QUEUE_EARLY_BOOT_KEYS 351 /* 352 * To track keys that need to be measured. 353 */ 354 struct ima_key_entry { 355 struct list_head list; 356 void *payload; 357 size_t payload_len; 358 char *keyring_name; 359 }; 360 void ima_init_key_queue(void); 361 bool ima_should_queue_key(void); 362 bool ima_queue_key(struct key *keyring, const void *payload, 363 size_t payload_len); 364 void ima_process_queued_keys(void); 365 #else 366 static inline void ima_init_key_queue(void) {} 367 static inline bool ima_should_queue_key(void) { return false; } 368 static inline bool ima_queue_key(struct key *keyring, 369 const void *payload, 370 size_t payload_len) { return false; } 371 static inline void ima_process_queued_keys(void) {} 372 #endif /* CONFIG_IMA_QUEUE_EARLY_BOOT_KEYS */ 373 374 /* LIM API function definitions */ 375 int ima_get_action(struct mnt_idmap *idmap, struct inode *inode, 376 const struct cred *cred, struct lsm_prop *prop, int mask, 377 enum ima_hooks func, int *pcr, 378 struct ima_template_desc **template_desc, 379 const char *func_data, unsigned int *allowed_algos); 380 int ima_must_measure(struct inode *inode, int mask, enum ima_hooks func); 381 int ima_collect_measurement(struct ima_iint_cache *iint, struct file *file, 382 void *buf, loff_t size, enum hash_algo algo, 383 struct modsig *modsig); 384 void ima_store_measurement(struct ima_iint_cache *iint, struct file *file, 385 const unsigned char *filename, 386 struct evm_ima_xattr_data *xattr_value, 387 int xattr_len, const struct modsig *modsig, int pcr, 388 struct ima_template_desc *template_desc); 389 int process_buffer_measurement(struct mnt_idmap *idmap, 390 struct inode *inode, const void *buf, int size, 391 const char *eventname, enum ima_hooks func, 392 int pcr, const char *func_data, 393 bool buf_hash, u8 *digest, size_t digest_len); 394 void ima_audit_measurement(struct ima_iint_cache *iint, 395 const unsigned char *filename); 396 int ima_alloc_init_template(struct ima_event_data *event_data, 397 struct ima_template_entry **entry, 398 struct ima_template_desc *template_desc); 399 int ima_store_template(struct ima_template_entry *entry, int violation, 400 struct inode *inode, 401 const unsigned char *filename, int pcr); 402 void ima_free_template_entry(struct ima_template_entry *entry); 403 const char *ima_d_path(const struct path *path, char **pathbuf, char *filename); 404 405 /* IMA policy related functions */ 406 int ima_match_policy(struct mnt_idmap *idmap, struct inode *inode, 407 const struct cred *cred, struct lsm_prop *prop, 408 enum ima_hooks func, int mask, int flags, int *pcr, 409 struct ima_template_desc **template_desc, 410 const char *func_data, unsigned int *allowed_algos); 411 void ima_init_policy(void); 412 void ima_update_policy(void); 413 void ima_update_policy_flags(void); 414 ssize_t ima_parse_add_rule(char *); 415 void ima_delete_rules(void); 416 int ima_check_policy(void); 417 void *ima_policy_start(struct seq_file *m, loff_t *pos); 418 void *ima_policy_next(struct seq_file *m, void *v, loff_t *pos); 419 void ima_policy_stop(struct seq_file *m, void *v); 420 int ima_policy_show(struct seq_file *m, void *v); 421 422 /* Appraise integrity measurements */ 423 #define IMA_APPRAISE_ENFORCE 0x01 424 #define IMA_APPRAISE_FIX 0x02 425 #define IMA_APPRAISE_LOG 0x04 426 #define IMA_APPRAISE_MODULES 0x08 427 #define IMA_APPRAISE_FIRMWARE 0x10 428 #define IMA_APPRAISE_POLICY 0x20 429 #define IMA_APPRAISE_KEXEC 0x40 430 431 #ifdef CONFIG_IMA_APPRAISE 432 int ima_check_blacklist(struct ima_iint_cache *iint, 433 const struct modsig *modsig, int pcr); 434 int ima_appraise_measurement(enum ima_hooks func, struct ima_iint_cache *iint, 435 struct file *file, const unsigned char *filename, 436 struct evm_ima_xattr_data *xattr_value, 437 int xattr_len, const struct modsig *modsig); 438 int ima_must_appraise(struct mnt_idmap *idmap, struct inode *inode, 439 int mask, enum ima_hooks func); 440 void ima_update_xattr(struct ima_iint_cache *iint, struct file *file); 441 enum integrity_status ima_get_cache_status(struct ima_iint_cache *iint, 442 enum ima_hooks func); 443 enum hash_algo ima_get_hash_algo(const struct evm_ima_xattr_data *xattr_value, 444 int xattr_len); 445 int ima_read_xattr(struct dentry *dentry, 446 struct evm_ima_xattr_data **xattr_value, int xattr_len); 447 void __init init_ima_appraise_lsm(const struct lsm_id *lsmid); 448 449 #else 450 static inline int ima_check_blacklist(struct ima_iint_cache *iint, 451 const struct modsig *modsig, int pcr) 452 { 453 return 0; 454 } 455 456 static inline int ima_appraise_measurement(enum ima_hooks func, 457 struct ima_iint_cache *iint, 458 struct file *file, 459 const unsigned char *filename, 460 struct evm_ima_xattr_data *xattr_value, 461 int xattr_len, 462 const struct modsig *modsig) 463 { 464 return INTEGRITY_UNKNOWN; 465 } 466 467 static inline int ima_must_appraise(struct mnt_idmap *idmap, 468 struct inode *inode, int mask, 469 enum ima_hooks func) 470 { 471 return 0; 472 } 473 474 static inline void ima_update_xattr(struct ima_iint_cache *iint, 475 struct file *file) 476 { 477 } 478 479 static inline enum integrity_status 480 ima_get_cache_status(struct ima_iint_cache *iint, enum ima_hooks func) 481 { 482 return INTEGRITY_UNKNOWN; 483 } 484 485 static inline enum hash_algo 486 ima_get_hash_algo(struct evm_ima_xattr_data *xattr_value, int xattr_len) 487 { 488 return ima_hash_algo; 489 } 490 491 static inline int ima_read_xattr(struct dentry *dentry, 492 struct evm_ima_xattr_data **xattr_value, 493 int xattr_len) 494 { 495 return 0; 496 } 497 498 static inline void __init init_ima_appraise_lsm(const struct lsm_id *lsmid) 499 { 500 } 501 502 #endif /* CONFIG_IMA_APPRAISE */ 503 504 #ifdef CONFIG_IMA_APPRAISE_MODSIG 505 int ima_read_modsig(enum ima_hooks func, const void *buf, loff_t buf_len, 506 struct modsig **modsig); 507 void ima_collect_modsig(struct modsig *modsig, const void *buf, loff_t size); 508 int ima_get_modsig_digest(const struct modsig *modsig, enum hash_algo *algo, 509 const u8 **digest, u32 *digest_size); 510 int ima_get_raw_modsig(const struct modsig *modsig, const void **data, 511 u32 *data_len); 512 void ima_free_modsig(struct modsig *modsig); 513 #else 514 static inline int ima_read_modsig(enum ima_hooks func, const void *buf, 515 loff_t buf_len, struct modsig **modsig) 516 { 517 return -EOPNOTSUPP; 518 } 519 520 static inline void ima_collect_modsig(struct modsig *modsig, const void *buf, 521 loff_t size) 522 { 523 } 524 525 static inline int ima_get_modsig_digest(const struct modsig *modsig, 526 enum hash_algo *algo, const u8 **digest, 527 u32 *digest_size) 528 { 529 return -EOPNOTSUPP; 530 } 531 532 static inline int ima_get_raw_modsig(const struct modsig *modsig, 533 const void **data, u32 *data_len) 534 { 535 return -EOPNOTSUPP; 536 } 537 538 static inline void ima_free_modsig(struct modsig *modsig) 539 { 540 } 541 #endif /* CONFIG_IMA_APPRAISE_MODSIG */ 542 543 /* LSM based policy rules require audit */ 544 #ifdef CONFIG_IMA_LSM_RULES 545 546 #define ima_filter_rule_init security_audit_rule_init 547 #define ima_filter_rule_free security_audit_rule_free 548 #define ima_filter_rule_match security_audit_rule_match 549 550 #else 551 552 static inline int ima_filter_rule_init(u32 field, u32 op, char *rulestr, 553 void **lsmrule, gfp_t gfp) 554 { 555 return -EINVAL; 556 } 557 558 static inline void ima_filter_rule_free(void *lsmrule) 559 { 560 } 561 562 static inline int ima_filter_rule_match(struct lsm_prop *prop, u32 field, u32 op, 563 void *lsmrule) 564 { 565 return -EINVAL; 566 } 567 #endif /* CONFIG_IMA_LSM_RULES */ 568 569 #ifdef CONFIG_IMA_READ_POLICY 570 #define POLICY_FILE_FLAGS (S_IWUSR | S_IRUSR) 571 #else 572 #define POLICY_FILE_FLAGS S_IWUSR 573 #endif /* CONFIG_IMA_READ_POLICY */ 574 575 #endif /* __LINUX_IMA_H */ 576