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